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Articoli di riviste sul tema "Population balance of protein species":

1

Behie, Alison M., e Mary S. M. Pavelka. "Food selection in the black howler monkey following habitat disturbance: implications for the importance of mature leaves". Journal of Tropical Ecology 28, n. 2 (13 febbraio 2012): 153–60. http://dx.doi.org/10.1017/s0266467411000678.

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Abstract:Primates commonly consume leaves that are high in protein but low in digestion-inhibiting fibre. Due to the fact that mature leaves do not meet these criteria, they are typically avoided and many leaf-eating primates select for leaves high in protein and low in fibre leading to the theory that food selection is based on protein maximization. However, feeding records for a population of black howler monkey (Alouatta pigra) in Monkey River, Belize, collected over a 5-y period, together with synchronous phenological data, indicate that this population does not meet the expectation and actually prefer mature leaves. This study aims to describe the nutritional composition of the food supply and investigate the possibility that, rather than to maximize protein ingestion, mature leaves are eaten to balance nutrient intake. Macronutrient analyses (moisture, lipids, protein, NDF, ADF and simple sugars) were conducted on a sample of 96 plant samples from 18 food species of this population of black howler. Results reported here show that mature leaves eaten by howlers in this forest contain sufficient protein to meet minimum metabolic requirements (range: 11.6–24%; mean: 16.4% ± 3.8%) and have significantly higher concentrations of simple sugars than young leaves (means of 7.2% ± 2.7% vs. 4.4% ± 2.3% respectively). Thus, it appears that mature leaf ingestion is likely serving to balance energy and protein intake. This result may be due to the disruptive effects of a hurricane in 2001 that resulted in a loss of 80% of the howler population, changed forest composition and may have affected plant chemistry. Despite this, the data reported here suggest that the accepted view that mature leaves are simply fallback foods for primates, eaten only in times of preferred food scarcity, may have to be revised.
2

Zaborowska, Julia, Bartosz Łabiszak, Annika Perry, Stephen Cavers e Witold Wachowiak. "Candidate Genes for the High-Altitude Adaptations of Two Mountain Pine Taxa". International Journal of Molecular Sciences 22, n. 7 (27 marzo 2021): 3477. http://dx.doi.org/10.3390/ijms22073477.

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Mountain plants, challenged by vegetation time contractions and dynamic changes in environmental conditions, developed adaptations that help them to balance their growth, reproduction, survival, and regeneration. However, knowledge regarding the genetic basis of species adaptation to higher altitudes remain scarce for most plant species. Here, we attempted to identify such corresponding genomic regions of high evolutionary importance in two closely related European pines, Pinus mugo and P. uncinata, contrasting them with a reference lowland relative—P. sylvestris. We genotyped 438 samples at thousands of single nucleotide polymorphism (SNP) markers, tested their genetic differentiation and population structure followed by outlier detection and gene ontology annotations. Markers clearly differentiated the species and uncovered patterns of population structure in two of them. In P. uncinata three Pyrenean sites were grouped together, while two outlying populations constituted a separate cluster. In P. sylvestris, Spanish population appeared distinct from the remaining four European sites. Between mountain pines and the reference species, 35 candidate genes for altitude-dependent selection were identified, including such encoding proteins responsible for photosynthesis, photorespiration and cell redox homeostasis, regulation of transcription, and mRNA processing. In comparison between two mountain pines, 75 outlier SNPs were found in proteins involved mainly in the gene expression and metabolism.
3

Lang, Yifei, Wentao Li, Zeshi Li, Danielle Koerhuis, Arthur C. S. van den Burg, Erik Rozemuller, Berend-Jan Bosch et al. "Coronavirus hemagglutinin-esterase and spike proteins coevolve for functional balance and optimal virion avidity". Proceedings of the National Academy of Sciences 117, n. 41 (29 settembre 2020): 25759–70. http://dx.doi.org/10.1073/pnas.2006299117.

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Human coronaviruses OC43 and HKU1 are respiratory pathogens of zoonotic origin that have gained worldwide distribution. OC43 apparently emerged from a bovine coronavirus (BCoV) spillover. All three viruses attach to 9-O-acetylated sialoglycans via spike protein S with hemagglutinin-esterase (HE) acting as a receptor-destroying enzyme. In BCoV, an HE lectin domain promotes esterase activity toward clustered substrates. OC43 and HKU1, however, lost HE lectin function as an adaptation to humans. Replaying OC43 evolution, we knocked out BCoV HE lectin function and performed forced evolution-population dynamics analysis. Loss of HE receptor binding selected for second-site mutations in S, decreasing S binding affinity by orders of magnitude. Irreversible HE mutations led to cooperativity in virus swarms with low-affinity S minority variants sustaining propagation of high-affinity majority phenotypes. Salvageable HE mutations induced successive second-site substitutions in both S and HE. Apparently, S and HE are functionally interdependent and coevolve to optimize the balance between attachment and release. This mechanism of glycan-based receptor usage, entailing a concerted, fine-tuned activity of two envelope protein species, is unique among CoVs, but reminiscent of that of influenza A viruses. Apparently, general principles fundamental to virion–sialoglycan interactions prompted convergent evolution of two important groups of human and animal pathogens.
4

Hodges, K. E., e A. R. E. Sinclair. "Does predation risk cause snowshoe hares to modify their diets?" Canadian Journal of Zoology 81, n. 12 (1 dicembre 2003): 1973–85. http://dx.doi.org/10.1139/z03-192.

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Snowshoe hares (Lepus americanus) undergo a 10-year population cycle with several years of low densities. Several authors have suggested that snowshoe hares modify their foraging behaviour to reduce predation risk during the low phase, resulting in protein-poor diets and poor body condition. We test that idea by using a factorial manipulation of food supplementation and predator reduction and by examining the species composition, browse size, and nutritional quality of snowshoe hare diets during 3 years of low snowshoe hare abundance in southwestern Yukon. Our results negate the hypothesis that snowshoe hares change their diets in response to mammalian predators during the cyclic low phase. Snowshoe hares on the different treatments had diets that differed in species composition and twig sizes, but protected hares did not have higher protein diets than unprotected hares. Snowshoe hares with access to supplemental food ate more fibrous and lower protein natural browse than unfed hares, showing that they did not choose diets primarily for protein content. Instead, snowshoe hares converted a wide range of forage availabilities into similar intakes of protein and fibre, despite variation in predator presence. Our results suggest that snowshoe hares select their diets to balance the protein and fibre contents. Although sublethal effects of predators may influence cyclic dynamics, our results show that such a feedback does not occur via a nutritional mechanism, counter to previous suggestions.
5

Lou, Marjorie F. "Glutathione and Glutaredoxin in Redox Regulation and Cell Signaling of the Lens". Antioxidants 11, n. 10 (1 ottobre 2022): 1973. http://dx.doi.org/10.3390/antiox11101973.

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The ocular lens has a very high content of the antioxidant glutathione (GSH) and the enzymes that can recycle its oxidized form, glutathione disulfide (GSSG), for further use. It can be synthesized in the lens and, in part, transported from the neighboring anterior aqueous humor and posterior vitreous body. GSH is known to protect the thiols of the structural lens crystallin proteins from oxidation by reactive oxygen species (ROS) so the lens can maintain its transparency for proper visual function. Age-related lens opacity or senile cataract is the major visual impairment in the general population, and its cause is closely associated with aging and a constant exposure to environmental oxidative stress, such as ultraviolet light and the metabolic end product, H2O2. The mechanism for senile cataractogenesis has been hypothesized as the results of oxidation-induced protein-thiol mixed disulfide formation, such as protein-S-S-glutathione and protein-S-S-cysteine mixed disulfides, which if not reduced in time, can change the protein conformation to allow cascading modifications of various kinds leading to protein–protein aggregation and insolubilization. The consequence of such changes in lens structural proteins is lens opacity. Besides GSH, the lens has several antioxidation defense enzymes that can repair oxidation damage. One of the specific redox regulating enzymes that has been recently identified is thioltransferase (glutaredoxin 1), which works in concert with GSH, to reduce the oxidative stress as well as to regulate thiol/disulfide redox balance by preventing protein-thiol mixed disulfide accumulation in the lens. This oxidation-resistant and inducible enzyme has multiple physiological functions. In addition to protecting structural proteins and metabolic enzymes, it is able to regulate the redox signaling of the cells during growth factor-stimulated cell proliferation and other cellular functions. This review article focuses on describing the redox regulating functions of GSH and the thioltransferase enzyme in the ocular lens.
6

Larsen, Torben, Shakuntala H. Thilsted, Katja Kongsbak e Marianne Hansen. "Whole small fish as a rich calcium source". British Journal of Nutrition 83, n. 2 (febbraio 2000): 191–96. http://dx.doi.org/10.1017/s0007114500000246.

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The present rat balance study investigated Ca availability from the whole indigenous small fish species, mola (Amblypharyngodon mola) from Bangladesh and from skimmed milk. Four groups of six young male rats each were fedad libitumwith diets containing either small fish or milk, at 100 or 160 g crude protein/kg diet dry matter. The study was conducted for 28 d and faeces and urine samples were collected in two balance periods: days 8–14 and 22–28. The Ca and N contents of the diets, faeces and urine were analysed. Ca intake, fractional Ca absorption and Ca retention in relation to N retention were measured. Digestibility and protein utilization of the experimental diets, weight gain of the rats, femur bone weight and mineral composition as well as bone alkaline phosphatase activity were also determined. It was concluded from the values of these variables that Ca from small fish with bones was available and appeared to be a useful Ca source in rats, though perhaps not as available as Ca from milk. This study suggests that small fish with bones may be an important source of Ca in human diets. Promotion of the production and consumption of small fish in population groups with low intakes of milk and milk products should therefore be encouraged.
7

Ellsworth, Ethan, Aaron J. Wirsing, Lisa A. Shipley e Dennis L. Murray. "Do measures of plant intake and digestibility from captive feeding trials align with foraging patterns of free-ranging snowshoe hares?" Wildlife Research 40, n. 5 (2013): 349. http://dx.doi.org/10.1071/wr13106.

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Context Measures of intake and digestibility from captive feeding experiments are often used to evaluate the nutritional value of plant species to herbivores; however, there is question about how well plant-quality rankings from these trials predict foraging patterns of free-ranging animals. Studies addressing the alignment of results from feeding trials and herbivory in the field using captive and free-roaming conspecifics are needed. Aims Our goal was to compare the feeding patterns of snowshoe hares in captive intake and digestion trials with those of free-living conspecifics in the species’ south-western range. Methods We conducted in vivo intake and digestion trials using captive hares to determine quality and consumption levels of the predominant conifer species in our study system. In the field, we quantified browsing intensity and over-winter depletion patterns of these conifers. We then compared voluntary intake and nutritional quality measured in captivity to consumption in the field. Key results Digestible energy (DE, kJ g–1) of conifers ranged from 11.0 (Pinus contorta) to 13.8 (Pseudotsuga menziesii) among six conifers, and digestible protein (DP, g protein per 100 g feed) from 1.2 (Thuja plicata) to 2.7 (P. contorta). During digestion trials, single-species intake was correlated with the content of digestible protein (DP) and digestible energy (DE). Hares maintained energy balance when fed two single-species diets (Pinus contorta, Pseudotsuga menziesii) and a mixed-species diet. Conifer species on which hares were able to maintain body mass (Pinus contorta, Picea engelmannii, Pseudotsuga menziesii) also tended to be the most heavily exploited by free-living hares. DP content of browse species predicted both browsing intensity and overwinter depletion of conifer species. Conclusions Voluntary intake and nutritional quality of browse, especially DP, successfully predicted foraging patterns of free-ranging conspecifics. Implications Intake and digestion trials can be a useful tool for better understanding patterns of herbivory in the field, and winter habitat quality for populations in this region is likely to be influenced by access to the most energy- and protein-rich conifers.
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Vinod, Nikhra. "The Trans-zoonotic Virome interface: Measures to balance, control and treat epidemics". Annals of Biomedical Science and Engineering 4, n. 1 (9 aprile 2020): 020–27. http://dx.doi.org/10.29328/journal.abse.1001009.

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The global virome: The viruses have a global distribution, phylogenetic diversity and host specificity. They are obligate intracellular parasites with single- or double-stranded DNA or RNA genomes, and afflict bacteria, plants, animals and human population. The viral infection begins when surface proteins bind to receptor proteins on the host cell surface, followed by internalisation, replication and lysis. Further, trans-species interactions of viruses with bacteria, small eukaryotes and host are associated with various zoonotic viral diseases and disease progression. Virome interface and transmission: The cross-species transmission from their natural reservoir, usually mammalian or avian, hosts to infect human-being is a rare probability, but occurs leading to the zoonotic human viral infection. The factors like increased human settlements and encroachments, expanded travel and trade networks, altered wildlife and livestock practices, modernised and mass-farming practices, compromised ecosystems and habitat destruction, and global climate change have impact on the interactions between virome and its hosts and other species and act as drivers of trans-species viral spill-over and human transmission. Zoonotic viral diseases and epidemics: The zoonotic viruses have caused various deadly pandemics in human history. They can be further characterized as either newly emerging or re-emerging infectious diseases, caused by pathogens that historically have infected the same host species, but continue to appear in new locations or in drug-resistant forms, or reappear after apparent control or elimination. The prevalence of zoonoses underlines importance of the animal–human–ecosystem interface in disease transmission. The present COVID-19 infection has certain distinct features which suppress the host immune response and promote the disease potential. Treatment for epidemics like covid-19: It appears that certain nutraceuticals may provide relief in clinical symptoms to patients infected with encapsulated RNA viruses such as influenza and coronavirus. These nutraceuticals appear to reduce the inflammation in the lungs and help to boost type 1 interferon response to these viral infections. The human intestinal microbiota acting in tandem with the host’s defence and immune system, is vital for homeostasis and preservation of health. The integrity and balanced activity of the gut microbes is responsible for the protection from disease states including viral infections. Certain probiotics may help in improving the sensitivity and effectivity of immune system against viral infections. Currently, antiviral therapy is available only for a limited number of zoonotic viral infections. Because viruses are intracellular parasites, antiviral drugs are not able to deactivate or destroy the virus but can reduce the viral load by inhibiting replication and facilitating the host’s innate immune mechanisms to neutralize the virus. Conclusion: Lessons from recent viral epidemics - Considering that certain nutraceuticals have demonstrated antiviral effects in both clinical and animal studies, further studies are required to establish their therapeutic efficacy. The components of nutraceuticals such as luteolin, apigenin, quercetin and chlorogenic acid may be useful for developing a combo-therapy. The use of probiotics to enhance immunity and immune response against viral infections is a novel possibility. The available antiviral therapy is inefficient in deactivating or destroying the infecting viruses, may help in reducing the viral load by inhibiting replication. The novel efficient antiviral agents are being explored.
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Buzoianu, Stefan G., Ava M. Firth, CallaBria Putrino e Fabio Vannucci. "Early-Life Intake of an Isotonic Protein Drink Improves the Gut Microbial Profile of Piglets". Animals 10, n. 5 (18 maggio 2020): 879. http://dx.doi.org/10.3390/ani10050879.

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A healthy microbial community in the gut of piglets is critical to minimize the negative performance consequences associated with dietary and environmental changes that occur at weaning. Tonisity Px, an isotonic protein drink, is a potential alternative to balance the gut microbiota as it contains key ingredients for nourishing the small intestine. In the present study, 16 litters comprising 161 piglets were randomly allocated to a group to which Tonisity Px was provided from days 2 to 8 of age (TPX group) or to a control group, to which no Tonisity Px was provided. The TPX group also received Tonisity Px in the 3 days before and after weaning. At days 9, 17, and 30 of age, fecal and ileum samples were collected from piglets belonging to both groups and analyzed using 16S rRNA gene sequencing, semiquantitative PCR of Rotavirus serogroups, and semiquantitative Escherichia coli culture. Overall, Tonisity Px increased the abundance of beneficial bacterial populations (Lactobacillus and Bacteroides species) and reduced potentially pathogenic bacterial populations (E. coli and Prevotellaceae), in both the pre-weaning and post-weaning periods.
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Wang, Yanwen, Sean Tibbetts e Patrick McGinn. "Microalgae as Sources of High-Quality Protein for Human Food and Protein Supplements". Foods 10, n. 12 (4 dicembre 2021): 3002. http://dx.doi.org/10.3390/foods10123002.

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As a result of population growth, an emerging middle-class, and a more health-conscious society concerned with overconsumption of fats and carbohydrates, dietary protein intake is on the rise. To address this rapid change in the food market, and the subsequent high demand for protein products, agriculture, aquaculture, and the food industry have been working actively in recent years to increase protein product output from both production and processing aspects. Dietary proteins derived from animal sources are of the highest quality, containing well-balanced profiles of essential amino acids that generally exceed those of other food sources. However, as a result of studies highlighting low production efficiency (e.g., feed to food conversion) and significant environmental impacts, together with the negative health impacts associated with the dietary intake of some animal products, especially red meats, the consumption of animal proteins has been remaining steady or even declining over the past few decades. To fill this gap, researchers and product development specialists at all levels have been working closely to discover new sources of protein, such as plant-based ingredients. In this regard, microalgae have been recognized as strategic crops, which, due to their vast biological diversity, have distinctive phenotypic traits and interactions with the environment in the production of biomass and protein, offering possibilities of production of large quantities of microalgal protein through manipulating growing systems and conditions and bioengineering technologies. Despite this, microalgae remain underexploited crops and research into their nutritional values and health benefits is in its infancy. In fact, only a small handful of microalgal species are being produced at a commercial scale for use as human food or protein supplements. This review is intended to provide an overview on microalgal protein content, its impact by environmental factors, its protein quality, and its associated evaluation methods. We also attempt to present the current challenges and future research directions, with a hope to enhance the research, product development, and commercialization, and ultimately meet the rapidly increasing market demand for high-quality protein products.

Tesi sul tema "Population balance of protein species":

1

Grancic, Peter. "Population balance modelling of non-native protein aggregation". Thesis, University of Strathclyde, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510725.

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Liu, Weiji. "Rôle de la micelle de caséine sur la dénaturation thermique des solutions de protéines de lactosérum et les mécanismes d'encrassement". Electronic Thesis or Diss., Université de Lille (2022-....), 2022. http://www.theses.fr/2022ULILR014.

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Le présent travail est une contribution pour mieux comprendre l’influence des micelles de caseine sur l’encrassement de solutions de protéines sériques. En particulier, des approches expérimentales et numériques ont été réalisées, à des tailles laboratoires et pilotes, pour décrire les phénomènes de dénaturation et mieux cerner le rôle du calcium dans les mécanismes d’encrassement. Tout d'abord, l'effet du ratio massique caséine / lactosérum sur les performances d'encrassement des protéines de lactosérum a été étudié dans un échangeur à Plaques à l'échelle pilote. La masse totale du dépôt d'encrassement chute d’abord de manière significative avec l'augmentation de la concentration en caséine, atteignant un minimum quand le ratio vaut 0,2. Au-delà de cette valeur, la masse de dépôt réaugmente. La chute de la masse du dépôt, pour un ratio ≤ 0,2, ne semble pas être corrélée à la dénaturation thermique du BLG mais plus probablement due à la modification des interactions minérales introduites par la caséine. L'augmentation de la masse de dépôt, pour un ratio ≥ 0,2, semble être liée à une co-précipitation du complexe BLG-caséine qui augmente l'encrassement. Il est suggéré que la présence de caséine micellaire modifie profondément l'équilibre calcique en solution et que la teneur en nanocluster de Ca-P modifie fortement les interactions entre les espèces protéiques et les minéraux (calcium ionique, Ca-P) affectant ainsi la dénaturation des protéines et la précipitation des minéraux. Un nouveau modèle cinétique concernant le dépliement thermique et l'agrégation de BLG a été établi. Ce modèle est en mesure de justifier la rupture de pente dans le diagramme d'Arrhenius et de fournir des informations thermodynamiques détaillées pour les processus de dépliement et d'agrégation. Sur la base de ce modèle, il a été confirmé que le calcium ionique avait un rôle protecteur sur le dépliement thermique du BLG à basse température. En revanche, à des températures plus élevées, le calcium favorise l'agrégation et la formation d'espèces BLG dépliées. Un dispositif d'encrassement à l'échelle laboratoire a été construit et tester avec des protéines de lactosérum en régime laminaire. Un modèle CFD 3D réaliste a été implémenté simulant à la fois les réactions au cœur du fluide et en surface. Les résultats ont montré une relation linéaire entre le facteur pré-exponentiel et la concentration de calcium, ce qui suggère que l'encrassement nécessite qu’une seule molécule de calcium soit associée à une protéine de BLG. Il est confirmé que le calcium est essentiel à l'encrassement avec des effets significatifs à la fois sur les processus de dénaturation thermique et sur la croissance du dépôt. Enfin, l'effet du ratio caséine / lactosérum sur l'encrassement a été étudié avec un dispositif d'encrassement de laboratoire. Les résultats laboratoires montrent que la caséine réduit l’aptitude à l’encrassement comme déterminé précédemment avec l’installation pilote. Cependant, dans ce cas, l'encrassement reste à un niveau faible y compris pour des ratios élevés (jusqu'à 4). La présence de caséines individuelles dans la phase sérique a été considérée comme responsable de cette atténuation de l'encrassement, probablement par leurs activités de type chaperon. Cependant, quand le pH de la solution d'encrassement est fixé à 6,6, il est démontré que la caséine perd son effet d'atténuation de l'encrassement pour des ratios plus élevés. Ce comportement est lié à sa faible capacité de micelle de caséine à contrôler le calcium ionique dans la phase sérique à un pH plus bas, entraînant une concentration plus élevée en calcium facilitant la dénaturation de la BLG et l'accumulation de dépôts. Une quantité plus faible de caséines dissociées dans la phase sérique à pH 6,6 pourrait aussi expliquer l'augmentation de la masse d'encrassement car elles ne sont pas en concentration suffisantes pour remplir des fonctions de type chaperon
The present work is a contribution to better understand the influence of casein micelles on the fouling of serum whey protein solutions. In particular, experimental and numerical approaches have been carried out, at laboratory and pilot scales, to describe denaturation phenomena and better understand the role of calcium in fouling mechanisms. First of all, the effect of casein/whey mass ratio on the whey protein fouling performance was investigated in a pilot-scale PHE. The total fouling deposit mass drop significantly with the addition of casein, resulting in a minimum value located at Casein/WPI of 0.2. Exceeding this critical ratio, fouling deposit increased with elevated casein concentrations. The deposit mass drop (Casein/WPI ≤ 0.2) is unlikely to be linked to the thermal denaturation of BLG and is more probably due to the change in mineral interactions introduced by casein. The increased fouling mass (Casein/WPI ≥ 0.2) was attributed to a co-precipitation of BLG-casein complex that enhances the fouling. It is proposed that micellar casein change deeply the calcium balance and the content of CaP nanocluster modifies sharply the interactions which occur between protein species (BLG, caseins) and mineral elements (ionic calcium, Ca-P) thereby affecting the protein denaturation and fouling behavior. A novel kinetic model concerning thermal unfolding and aggregation of BLG was established. This model interprets mathematically the break-slope behavior in the Arrhenius plot and provides detailed thermodynamic information for both unfolding and aggregation processes. Based on this model, it was confirmed that ionic calcium has a protective role on the thermal unfolding of BLG at low temperature. In contrast, at higher temperatures, calcium promotes aggregation and the formation of unfolded BLG species. A bench-scale fouling rig was built to perform whey protein fouling experiments in a laminar regime. A realistic 3D CFD model was achieved to simulate both the bulk and surface reactions. Results showed a linear relationship between the deposition pre-exponential factor and calcium concentration, suggesting the fouling is built in such a pattern that only one calcium ion per BLG molecule is involved. Calcium was confirmed to be essential to fouling growth with significant effects both on the thermal denaturation and deposition processes. Finally, the effect of casein/whey ratio on the whey protein fouling was investigated in the laboratory-scale fouling device. Results revealed a similar effect of casein on fouling mitigation as those found in the pilot plant. However, in this case, the fouling was suppressed and maintained at a low extent even at high Casein/WPI ratios (up to 4). The presence of individual caseins in the serum phase was considered to be responsible for this fouling mitigation probably through their chaperon-like activities. However, when the pH of the fouling solution is set at 6.6, casein is shown to lose its fouling-mitigating effect at higher ratios. This behavior is related to its weak ability of casein micelle to control ionic calcium in the serum phase at lower pH, resulting in higher calcium concentration facilitating BLG denaturation and deposition accumulation. A lower amount of dissociated caseins in the serum phase at pH 6.6 could also explain the increase in fouling mass because they are not in sufficient concentration to perform chaperone-like functions
3

Leite, Natália Alves. "Genetic diversity and susceptibility to Vip3Aa20 protein in Brazilian populations of Helicoverpa armigera and Helicoverpa zea (Lepidoptera: Noctuidae)". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-16062016-164838/.

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Helicoverpa armigera (Hübner) was officially reported in Brazil in 2013. This species is closely related to Helicoverpa zea (Boddie) and has caused significant crop damage in Brazil. The use of genetically modified crops expressing insecticidal protein from Bacillus thuringiensis (Berliner) has been one of the control tactics for managing these pests. Genetically modified maize expressing Vip3Aa20 was approved to commercial use in Brazil in 2009. Understanding the genetic diversity and the susceptibility to B. thuringiensis proteins in H. armigera and H. zea populations in Brazil are crucial for establishing Insect Resistance Management (IRM) programs in Brazil. Therefore, the objectives of this study were: (a) to infer demographic parameters and genetic structure of H. armigera and H. zea Brazil; (b) to assess the intra and interspecific gene flow and genetic diversity of H. armigera and H. zea; and (c) to evaluate the susceptibility to Vip3Aa20 protein in H. armigera and H. zea populations of Brazil. A phylogeographic analysis of field H. armigera and H. zea populations was performed using a partial sequence data from the cytochrome c oxidase I (COI) gene. H. armigera individuals were most prevalent on dicotyledonous hosts and H. zea individuals were most prevalent on maize crops. Both species showed signs of demographic expansion and no genetic structure. High genetic diversity and wide distribution were observed for H. armigera. A joint analysis indicated the presence of Chinese, Indian, and European lineages within the Brazilian populations of H. armigera. In the cross-species amplification study, seven microsatellite loci were amplified; and showed a potential hybrid offspring in natural conditions. Interespecific analyses using the same microsatellite loci with Brazilian H. armigera and H. zea in compare to the USA H. zea were also conducted. When analyses were performed within each species, 10 microsatellites were used for H. armigera, and eight for H. zea. We detected high intraspecific gene flow in populations of H. armigera and H. zea from Brazil and H. zea from the USA. Genetic diversity was similar for both species. However, H. armigera was more similar to H. zea from Brazil than H. zea from the USA and some putative hybrid individuals were found in Brazilian populations.Tthere was low gene flow between Brazilian and USA H. zea. The baseline susceptibility to Vip3Aa20 resulted in low interpopulation variation for H. zea (3-fold) and for H. armigera (5-fold), based on LC50. H. armigera was more tolerant to Vip3Aa20 than H. zea (≈ 40 to 75-fold, based on CL50). The diagnostic concentration for susceptibility monitoring, based on CL99, was fairly high (6,400 ng Vip3Aa20/cm2) for H. zea and not validated for H. armigera due to the high amount of protein needed for bioassays. Implementing IRM strategies to Vip3Aa20 in H. armigera and H. zea will be of a great challenge in Brazil, mainly due to the low susceptibility to Vip3Aa20 and high genetic diversity and gene flow in both species, besides a potential of hybrid individuals between H. armigera and H. zea under field conditions.
Helicoverpa armigera (Hübner) foi oficialmente reportada no Brasil em 2013. Esta espécie é estreitamente relacionada a Helicoverpa zea (Boddie) e tem causado danos significativos nas culturas no Brasil. O uso de plantas geneticamente modificadas, que expressam proteínas inseticidas de Bacillus thuringiensis (Berliner), tem sido uma das táticas de controle para o manejo dessas pragas. O milho geneticamente modificado que expressa Vip3Aa20 foi aprovado para comercialização no Brasil em 2009. O entendimento da diversidade genética e da suscetibilidade às proteínas de B. thuringiensis em populações de H. armigera e H. zea no Brasil são cruciais para o estabelecimento de programas de Manejo da Resistência de Insetos (MRI). Assim, os objetivos desse estudo foram: (a) inferir parâmetros demográficos e estrutura genética de H. armigera e H. zea no Brasil; (b) avaliar o fluxo gênico intra e interespecífico e a diversidade genética em H. armigera e H. zea; e (c) aferir a suscetibilidade de populações brasileiras de H. armigera e H. zea a proteína Vip3Aa20. Uma análise filogeográfica de populações de campo de H. armigera e H. zea foi realizada com o uso de sequências do gene citocromo c oxidase I (COI). Indivíduos de H. armigera foram mais prevalentes em dicotiledôneas e H. zea na cultura do milho. Ambas as espécies mostraram sinais de expansão demográfica e ausência de estrutura genética. Alta diversidade genética e ampla distribuição foram observadas em H. armigera. Análises conjuntas indicaram a presença de linhagens da China, Índia e Europa em populações brasileiras de H. armigera. A partir de um estudo de amplificação cruzada de microssatélites, sete locos amplificaram em ambas as espécies e evidenciaram a possibilidade de hibridização no campo. Estes mesmos locos foram usados para análises interespecíficas de H. armigera e H. zea do Brasil em comparação a H. zea dos EUA. Nas análises para cada espécie, 10 microssatélites foram usados para H. armigera e oito para H. zea. Alto fluxo gênico intraespecífico foi detectado em populações de H. armigera e H. zea. A diversidade genética foi similar em ambas as espécies. H. armigera foi mais similar a H. zea do Brasil que dos EUA e possíveis híbridos foram encontrados nas populações brasileiras. Houve um baixo fluxo gênico entre populações brasileiras e americanas de H. zea. A linha-básica de suscetibilidade a Vip3Aa20 resultou numa variação interpopulacional baixa em H. zea (3 vezes) e em H. armigera (5 vezes), baseada na CL50. H. armigera foi mais tolerante a Vip3Aa20 que H. zea (≈ 40 to 75 vezes, baseado na CL50). A concentração diagnóstica, baseada na CL99, foi bastante alta (6.400 ng Vip3Aa20/cm2) para H. zea e não validada para H. armigera devido à alta quantidade de proteína necessária para os bioensaios. A implementação de estratégias de MRI a Vip3Aa20 em H. armigera e H. zea serão um grande desafio no Brasil, principalmente devido à baixa suscetibilidade a Vip3Aa20 e alta diversidade genética e fluxo gênico em ambas as espécies, além da possibilidade de indivíduos híbridos entre H. armigera e H. zea nas condições de campo.

Libri sul tema "Population balance of protein species":

1

Beattie, R. Mark, Anil Dhawan e John W.L. Puntis. Cystic fibrosis. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780198569862.003.0021.

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Gastrointestinal manifestations 156Management of gastrointestinal symptoms in children with CF 158Nutrition in CF 158Nutritional management 159Vitamins 160The incidence of cystic fibrosis (CF) is around 1 in 2500. Cases are diagnosed as a consequence of population screening or high-risk screening, or following presentation with clinical symptoms typical of the disorder. The basic defect is in the CFTR (cystic fibrosis transmembrane conductance regulator) protein which codes for a cyclic adenosine monophosphate-regulated chloride transporter in epithelial cells of exocrine organs. This is involved in salt and water balance across epithelial surfaces. The gene is on chromosome 7. There are multiple known mutations, the most common being ...
2

Andersen, Ken H. Fish Ecology, Evolution, and Exploitation. Princeton University Press, 2019. http://dx.doi.org/10.23943/princeton/9780691192956.001.0001.

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Fish are one of the most important global food sources, supplying a significant share of the world's protein consumption. From stocks of wild Alaskan salmon and North Sea cod to entire fish communities with myriad species, fisheries require careful management to ensure that stocks remain productive, and mathematical models are essential tools for doing so. This book is an introduction to the modern size- and trait-based approach to fish populations and communities. It covers the theoretical foundations, mathematical formulations, and real-world applications of this powerful new modeling method, which is grounded in the latest ecological theory and population biology. It begins with fundamental assumptions on the level of individuals and goes on to cover population demography and fisheries impact assessments. The book shows how size- and trait-based models shed new light on familiar fisheries concepts such as maximum sustainable yield and fisheries selectivity—insights that classic age-based theory can't provide—and develops novel evolutionary impacts of fishing. It extends the theory to entire fish communities and uses it to support the ecosystem approach to fisheries management, and forges critical links between trait-based methods and evolutionary ecology. The book unifies the thinking in ecology and fisheries science and is an indispensable reference for anyone seeking to apply size- and trait-based models to fish demography, fisheries impact assessments, and fish evolutionary ecology.
3

Petrossian, Gohar A. The Last Fish Swimming. ABC-CLIO, LLC, 2019. http://dx.doi.org/10.5040/9798400676734.

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This book examines the global, local, and specific environmental factors that facilitate illegal fishing and proposes effective ways to reduce the opportunities and incentives that threaten the existence of the world’s fish. Humans are deeply dependent on fishing—globally, fish comprise 15 percent of the protein intake for approximately 3 billion people, and 8 percent of the global population depends on the fishing industry as their livelihood. The global fishing industry is plagued by illegal fishing, however, and many highly commercial species, such as cod, tuna, orange roughy, and swordfish, are extremely vulnerable. Through criminological analysis, The Last Fish Swimming emphasizes the importance of looking at specific environmental factors that make illegal fishing possible. It examines such factors as proximity to known ports where illegally caught fish can be landed without inspection (i.e., ports of convenience), fisheries monitoring, control and surveillance efforts, formal surveillance, and resource attractiveness in 53 countries that altogether represent 96 percent of the world’s fish catch. The book calls upon the global community to address the illegal depletion of the world’s fish stock and other similar threats to the world’s food supply and natural environment in order to ensure the sustainability of the planet’s fish and continuation of the legal fishing industry for generations to come.
4

Colloff, Matthew J. Dust Mites. CSIRO Publishing, 2009. http://dx.doi.org/10.1071/9780643100497.

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Dust mites are present in almost every home – in our beds, clothing and carpets. Conservatively, at least 100 million people are affected by house dust mite allergy worldwide, manifesting itself as asthma, rhinitis or atopic dermatitis. Despite the growing recognition of this major public health problem, there is still no simple, effective, generally applicable strategy for dust mite control. Dust Mites incorporates for the first time in a single volume the topics of systematics and identification, physiology, ecology, allergen biochemistry and molecular biology, epidemiology, mite control and allergen avoidance. It explains key biological and ecological concepts for non-specialist readers, discusses ecological research methods and includes identification keys to dust mite species and life-cycle stage. It also explores how characteristics of population growth, water balance and physiology of dust mites have contributed to their importance as allergenic organisms. Many chapters contain new data, or new analyses of existing data, including global distribution maps of the most important species. Importantly, the book emphasises that studies of the biology and ecology of house dust mites should be regarded within the context of allergic disease rather than as ends in themselves, and that approaches to mite control in clinical management are subject to the same series of ecological rules as any other major problem in pest management. This comprehensive reference is essential reading for anyone involved or interested in house dust mite research and management.
5

Allendorf, Fred W., W. Chris Funk, Sally N. Aitken, Margaret Byrne, Gordon Luikart e Agostinho Antunes. Conservation and the Genomics of Populations. 3a ed. Oxford University Press, 2022. http://dx.doi.org/10.1093/oso/9780198856566.001.0001.

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Loss of biodiversity is among the greatest problems facing the world today. Conservation and the Genomics of Populations gives a comprehensive overview of the essential background, concepts, and tools needed to understand how genetic information can be used to conserve species threatened with extinction, and to manage species of ecological or commercial importance. New molecular techniques, statistical methods, and computer programs, genetic principles, and methods are becoming increasingly useful in the conservation of biological diversity. Using a balance of data and theory, coupled with basic and applied research examples, this book examines genetic and phenotypic variation in natural populations, the principles and mechanisms of evolutionary change, the interpretation of genetic data from natural populations, and how these can be applied to conservation. The book includes examples from plants, animals, and microbes in wild and captive populations. This third edition has been thoroughly revised to include advances in genomics and contains new chapters on population genomics, genetic monitoring, and conservation genetics in practice, as well as new sections on climate change, emerging diseases, metagenomics, and more. More than one-third of the references in this edition were published after the previous edition. Each of the 24 chapters and the Appendix end with a Guest Box written by an expert who provides an example of the principles presented in the chapter from their own work. This book is essential for advanced undergraduate and graduate students of conservation genetics, natural resource management, and conservation biology, as well as professional conservation biologists and policy-makers working for wildlife and habitat management agencies. Much of the book will also interest nonprofessionals who are curious about the role of genetics in conservation and management of wild and captive populations.
6

Alexander, D. J., N. Phin e M. Zuckerman. Influenza. A cura di I. H. Brown. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780198570028.003.0037.

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Influenza is a highly infectious, acute illness which has affected humans and animals since ancient times. Influenza viruses form the Orthomyxoviridae family and are grouped into types A, B, and C on the basis of the antigenic nature of the internal nucleocapsid or the matrix protein. Infl uenza A viruses infect a large variety of animal species, including humans, pigs, horses, sea mammals, and birds, occasionally producing devastating pandemics in humans, such as in 1918 when it has been estimated that between 50–100 million deaths occurred worldwide.There are two important viral surface glycoproteins, the haemagglutinin (HA) and neuraminidase (NA). The HA binds to sialic acid receptors on the membrane of host cells and is the primary antigen against which a host’s antibody response is targeted. The NA cleaves the sialic acid bond attaching new viral particles to the cell membrane of host cells allowing their release. The NA is also the target of the neuraminidase inhibitor class of antiviral agents that include oseltamivir and zanamivir and newer agents such as peramivir. Both these glycoproteins are important antigens for inducing protective immunity in the host and therefore show the greatest variation.Influenza A viruses are classified into 16 antigenically distinct HA (H1–16) and 9 NA subtypes (N1–9). Although viruses of relatively few subtype combinations have been isolated from mammalian species, all subtypes, in most combinations, have been isolated from birds. Each virus possesses one HA and one NA subtype.Last century, the sudden emergence of antigenically different strains in humans, termed antigenic shift, occurred on three occasions, 1918 (H1N1), 1957 (H2N2) and 1968 (H3N2), resulting in pandemics. The frequent epidemics that occur between the pandemics are as a result of gradual antigenic change in the prevalent virus, termed antigenic drift. Epidemics throughout the world occur in the human population due to infection with influenza A viruses, such as H1N1 and H3N2 subtypes, or with influenza B virus. Phylogenetic studies have led to the suggestion that aquatic birds that show no signs of disease could be the source of many influenza A viruses in other species. The 1918 H1N1 pandemic strain is thought to have arisen as a result of spontaneous mutations within an avian H1N1 virus. However, most pandemic strains, such as the 1957 H2N2, 1968 H3N2 and 2009 pandemic H1N1, are considered to have emerged by genetic re-assortment of the segmented RNA genome of the virus, with the avian and human influenza A viruses infecting the same host.Influenza viruses do not pass readily between humans and birds but transmission between humans and other animals has been demonstrated. This has led to the suggestion that the proposed reassortment of human and avian influenza viruses takes place in an intermediate animal with subsequent infection of the human population. Pigs have been considered the leading contender for the role of intermediary because they may serve as hosts for productive infections of both avian and human viruses, and there is good evidence that they have been involved in interspecies transmission of influenza viruses; particularly the spread of H1N1 viruses to humans. Apart from public health measures related to the rapid identification of cases and isolation. The main control measures for influenza virus infections in human populations involves immunization and antiviral prophylaxis or treatment.

Capitoli di libri sul tema "Population balance of protein species":

1

Strasser, Barbara. "Nutrition and Aging: Nutrition Balance and Dietary Protein Needs". In Encyclopedia of Gerontology and Population Aging, 1–6. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-69892-2_130-1.

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Strasser, Barbara. "Nutrition and Aging: Nutrition Balance and Dietary Protein Needs". In Encyclopedia of Gerontology and Population Aging, 3546–51. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-22009-9_130.

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Bedrosian, Bryan. "Avian Predators in Rangelands". In Rangeland Wildlife Ecology and Conservation, 471–504. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-34037-6_14.

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AbstractManagement of avian predators in western rangelands is uniquely challenging due to differences in managing for/against particular species, management of sensitive prey species, long-standing human/wildlife conflicts, and the unique legal protections within this ecological group. In general, many avian predator species considered rangeland specialists have been declining due to habitat loss, fragmentation, human sensitivity, and direct persecution. Conversely, avian predators that are more human-tolerant and/or are subsidized by human activities are significantly increasing across rangelands. The complicated nature of inter- and intra-species guilds, coupled with human dynamics has created a challenging scenario for both management for avian predators, as well as their prey. Human-mediated population control, both legal and illegal, continues for avian predators to reduce livestock conflict, aid sensitive prey populations, and/or because of general predator persecution. Conversion of rangeland to development for energy, cultivation, and urbanization remains the largest impediment to maintaining viable, historical assemblages of avian predators. Large-scale habitat protections, reduction of invasive plants, and reducing wildfire will continue to enhance at-risk populations of predators and their prey. Further, mediating human-induced mortality risks will also aid at-risk predator populations, such as reducing direct killing (poisoning and shooting), secondary poisoning from varmint control and lead ammunition use, electrocutions, and vehicle strikes, while reducing anthropogenic subsidies can help curtail population expansion of corvids. Additional understanding of long-term, successful predator control efforts for corvids and mitigation options for declining raptors is needed to help balance the avian predator–prey dynamic in western rangelands.
4

Kreager, Philip. "2. Evolution in the History of Population Thought". In Human Evolutionary Demography, 27–56. Cambridge, UK: Open Book Publishers, 2024. http://dx.doi.org/10.11647/obp.0251.02.

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This chapter places evolutionary demography in the history of population thought, and more particularly in relations between demography and evolutionary population biology. Darwin conceived evolution as a dynamics of variation arising from the behaviour of populations at intra- and inter-species levels. While Malthus’s principle of population was an important early stimulus, Darwin resolved the core problem in evolution -- how mechanisms of variation combine to produce divergence of character -- by analogy to Smith’s account of the division of labour. With the benefit of hindsight, we can describe Darwinian population thinking as the first general methodology in which it became possible to combine bottom-up observation including enumeration of local population dynamics with top-down statistical methods. The two components entail different concepts of population, which may be characterised broadly as ‘open’ and ‘closed’. Their combination shows that evolutionary theory is rooted in the same sources of population thinking that gave rise to demography: the former lie in Classical population thinking and early modern population arithmetics, and the latter in 19th-century statistics and probability. Hereditary influences remained a ‘black box’ in Darwin’s theory, which only began to be unpacked with the rediscovery of Mendel’s research. The second half of the chapter traces the central role which demographic methods played in topical and analytical developments of the first half of the 20th century, including both the formulation and critique of eugenics, the emergence of population ecology, and the rise of the mathematical theory of population genetics. There is an irony here: even as demographic methods came to play an integral role, mainstream demographers became less and less involved. The ‘separatism’ of demography and evolutionary biology often remarked in the post-war era thus has deeper roots. These lie partly in topical issues, like reactions against eugenics, but more importantly in a conceptual shift in how we understand relationships between ultimate and proximate mechanisms of population change, and its implications for analysis and modelling. Evolutionary theory entails a balance of methods and insights drawing on both population concepts, which demography has not yet achieved. The concluding section provides examples of how current evolutionary demography is now integrating these developments into demographic explanation.
5

Wilson, Helen, Diana Calcraft, Cai Neville, Susan Lanham-New e Louise R. Durrant. "Bone Health, Fragility and Fractures". In Perspectives in Nursing Management and Care for Older Adults, 115–34. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-63892-4_9.

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AbstractAchieving and maintaining skeletal health throughout the life trajectory is essential for the prevention of bone diseases such as rickets, osteomalacia and osteoporosis. Rickets and osteomalacia are usually a result of calcium and/or vitamin D deficiency, causing softening of bones and bone pain, and both conditions are treatable with calcium and vitamin D supplementation. Osteoporosis is a multifaceted disease mainly affecting older people, and its pathogenesis (and hence treatment) is more complex. Untreated osteoporosis results in fragility fractures causing morbidity and increased mortality.Nutrition is one of many factors that influence bone mass and risk of bone disease. Developing a nutritional sciences approach is a feasible option for improving bone health.The importance of adequate calcium and vitamin D in ensuring skeletal integrity throughout the life course has a sound evidence base. Poor vitamin D status in population groups of all ages is widespread across many countries (including affluent and non-affluent areas). Public health approaches are required to correct this given the fact that vitamin D is not just required for musculoskeletal health but also for other health outcomes.Dietary protein may be beneficial for bone due to its effect of increasing insulin-like growth-factor-1 (IGF-1). Recent meta-analyses show that dietary protein has a beneficial role to play in bone health at all ages.Other nutritional factors and nutrients (such as potassium, magnesium, vitamin K and acid-base balance) are also likely to have an important role in bone health, though the literature is less clear in terms of the association/relationship and more research is required.
6

Honor, Richard, e Robert I. Colautti. "EICA 2.0: a general model of enemy release and defence in plant and animal invasions." In Plant invasions: the role of biotic interactions, 192–207. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789242171.0192.

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Abstract Plants and animals have evolved a variety of strategies to limit the negative fitness consequences of natural enemies (i.e. herbivores, predators, parasites and pathogens). Demographic bottlenecks occurring during the invasion process reduce the number of co-introduced natural enemies, providing opportunities to study rapid evolution in environments with different or reduced enemy loads. Enemy release theory provides a set of hypotheses and predictions about the role of natural enemies in the proliferation of invasive species. This body of theory includes the Enemy Release Hypothesis (ERH) and the related Evolution of Increased Competitive Ability Hypothesis (EICA), but there is often confusion about these hypotheses and the data needed to test them. We introduce a simple, general model of enemy release to identify and clarify some of the key assumptions and predictions implicit in enemy release theory and its impacts on invasion. Although introduced populations likely benefit from a reduction in the direct fitness impacts of natural enemies in the early stages of invasion, an evolutionary shift in resource allocation from defence to growth and reproduction is much less likely and depends on a delicate balance between the fitness costs and benefits of defence and the fitness impacts of natural enemies in both the native and introduced ranges. Even when the abundance of natural enemies is lower in the introduced range, the majority of scenarios do not favour evolution of less defended genotypes that are more competitive or more fecund, contrary to predictions of EICA. Perhaps surprisingly, we find that the level of damage by natural enemies in field surveys is not generally a good parameter for testing enemy release theory. Instead, common garden experiments characterizing fitness reaction norms of multiple genotypes from the native and introduced range are crucial to estimate the historic rate of adaptive evolution or predict it into the future. Incorporating spatial autocorrelation and methods from population genetics can further improve our understanding of the role of enemy release and evolution in the proliferation of invasive species.
7

Propper, Catherine R., Grant Robert Singleton, Jodi L. Sedlock, Richard E. Smedley, Oliver B. Frith, Molly E. Shuman-Goodier, Renee P. Lorica et al. "Faunal Biodiversity in Rice-Dominated Wetlands—An Essential Component of Sustainable Rice Production". In Closing Rice Yield Gaps in Asia, 93–120. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-37947-5_3.

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AbstractRice agriculture provides wetlands and complex habitats supporting biodiversity. Wetlands associated with rice agriculture since the 1960s have increased by 32% and now form nearly 12% of wetlands globally at a time when vast areas of natural wetlands are being lost. In this chapter, we set our sights beyond Sustainable Development Goal (SDG) 2 that focuses on ending hunger and achieving food security via the promotion of sustainable agriculture. Often, agricultural scientists are so motivated to achieve food security that they pay insufficient attention to the need to have a healthy and dynamic agroecosystem that promotes floral and faunal biodiversity, which may also provide ecosystem services including support for food security of smallholder families. Because of their aquatic, semi-aquatic, and terrestrial ecological phases, rice fields represent a changing mosaic of ecological niches and have the potential to sustain a broad diversity of wildlife. In addition, a multitude of studies have investigated how modifications to rice cultivation have the potential to support a greater diversity of species across biological scales while often maintaining or increasing yield. SDG 15 emphasizes the need to promote sustainable use of terrestrial ecosystems and halt biodiversity loss. Given the high losses in global biodiversity, especially in tropical zones where most of the world’s rice is grown, we set our sights on achieving both SDGs 2 and 15. We provide case studies on amphibians, bats, birds, and rodents living in and around irrigated rice-cropping systems. We report on transdisciplinary studies supported by CORIGAP that include agronomic, sociological, ecological, biochemical, environmental physiological, and genomic studies. Most of these studies identify potential positive ecosystem services provided by wildlife, which can lead to more sustainable and healthier rice production landscapes. We conclude that our current management of rice landscapes contributes to the biodiversity crisis. Rice production often overuses pesticides and fertilizers and applies unsustainable intensification practices and land modifications, which result in biodiversity loss. Finding a balance, where human population requirements for food are met without degrading the natural environment, is critical to the health of smallholder agricultural communities. We propose that future research and development projects need to: build capacity of countries to scale-up use of proven practices that reduce rice farming’s ecological footprint and conserve biodiversity, increase investment in biodiversity research in rice production landscapes, promote Green “Rice Value Chains” and “Agri-input Markets,” and monitor and evaluate the ecological benefits to biodiversity of broadscale promotion of sustainable rice production.
8

Choudhari, Jyoti K., J. Anandkumar, Mukesh K. Verma, Jyotsna Choubey e Biju P. Sahariah. "Ecophysiology and Genomics of N-cycling Microbes in the Environment". In Ammonia Oxidizing Bacteria, 135–46. Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/bk9781837671960-00135.

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The most prominent element of the Earth, nitrogen, exists in various forms owing to its wide oxidation state of −3 to +5, in the form of NH3, NH4+, NO, NO2, N2O, HNO3, HONO, PAN and many other organic N compounds. It is a primary component of life’s existence as it is involved in protein synthesis, the building blocks of organisms, as well as a tremendous number of protein-regulated biological activities. The nitrogen cycle maintains balance and the required recompense of nitrogen in the biosphere. Microbes enriched with various cellular and molecular elements contribute to the accomplishment of biological nitrogen by ammonia fixation, converting atmospheric nitrogen to the ammonia form so that plants or other producers can assimilate it, as well as nitrification and denitrification to release it from the biosphere as nitrogen gas. Phylogeny analysis, an essential biological tool, can express the comparison of genetic, individual, population, and species information in terms of morphology, behavioural, or molecular data. Phylogeny analysis estimates historic relationships between genes or species and describes these relationships in a branching diagram, a phylogenetic tree. This chapter discusses the essential concepts of groups of microbes (N-fixer, nitrifier and denitrifier), involved in the N-cycle, and their functions (transformation of nitrogen). Intra and inter-specific interactions among N-cycle microorganisms and their role in the global N-cycle are investigated to expand the understanding of nitrogen–microbe interactions using an omics approach.
9

Burnett, John. "Genetic markers for population studies-II Molecular markers". In Fungal Populations and Species, 47–64. Oxford University PressOxford, 2003. http://dx.doi.org/10.1093/oso/9780198515524.003.0004.

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Abstract A wide range of natural molecules exist such as particular secondary metabolites like the lichen acids which are produced by the fungal component, the whole protein content or specific polymorphic enzyme proteins. Unfortunately, characteristic species-specific molecules only occur sporadically amongst the fungi so that their use as markers is limited, although they are often characteristic of higher groups such as genera, sections or families.
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"LAGRANGIAN APPROACH: ONE-D CONSERVATION OF SPECIES AND POPULATION BALANCE". In Multiphase Flow and Fluidization, 413–22. Elsevier, 1994. http://dx.doi.org/10.1016/b978-0-08-051226-6.50021-2.

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Atti di convegni sul tema "Population balance of protein species":

1

Barouh, Nathalie, Claire Berton-Carabin, Thierry Chardot, Jean-Francois Fabre, Sabine D'andrea, Yann Gohon, Eric Lacroux et al. "Exploring Plant Biodiversity to Extract Oil Bodies for Sustainable Food Applications". In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/wmkj8057.

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Oleoproteaginous and cereal seeds enclose a wide range of nutriments such as lipids, proteins, polysaccharides and various mineral and organic micronutrients. These nutrients are found under the form of natural assemblies such as oil or protein bodies or starch granules, that have interesting functionalities (micronic sizes, surface activity, high physicochemical stability, etc.). These assemblies are extracted by various processes using energy, organic solvents, steam, alone or in combination. Thus, their natural structures are often strongly damaged, and some of their functionalities disappear. Storming through natural assemblies’ biodiversity to address the societal demand for more natural and minimally-processed food, seems promising. Indeed, the soft extraction of such assemblies could be an alternative to traditional intensive fractionation methods of plant raw materials to isolate target ingredients (sucrose, starch, refined oils, etc.). This would allow energy savings and avoid solvent use, but must be balanced with potential challenges of this new green refinery scheme. The purpose of the present work is to highlight the physicochemical properties of various oil bodies from diverse plant origins. A green refinery protocol is proposed for their extraction from various matrices. Then their size distribution, surface activity, resistance to oxidation and fatty acids and liposoluble vitamins bioaccessibility is also presented. Omega-3 rich sources (linseed, chia, hemp…) are of special interest to correct the low dietary intake of US and European population as well as the ω6/ω3 balance. Oil bodies from these plant species can thus constitute new dietary carriers of ω3 and other bioactive molecules. Moreover, the combination of oil bodies with specific features (fatty acid profiles, stabilities, vitamin contents) can help meeting the requirements of specific nutritional targets (infants, children, elderly, athletes, etc.). Altogether, we are convinced that the valorization of these diverse oil bodies can be a strategic route in the development of sustainable food systems.
2

Ameli, Forough, Bahram Dabir, Farzin Zokaee Ashtiani, Mehdad Mozaffarian e Kambiz Vafai. "Combined Models of Population Balance and Pore-Network to Explore the Mechanism of Protein Fouling in Porous Media". In POROUS MEDIA AND ITS APPLICATIONS IN SCIENCE, ENGINEERING, AND INDUSTRY: 3rd International Conference. AIP, 2010. http://dx.doi.org/10.1063/1.3453812.

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3

Bulimaga, Constantin, Victoria Nistreanu, Corina Certan, Olesea Gliga e Alina Larion. "Diversitatea vegetala si animala a ecosistemului urban Orhei". In Impactul antropic asupra calitatii mediului. Institute of Ecology and Geography, Republic of Moldova, 2019. http://dx.doi.org/10.53380/9789975330800.02.

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Lately, the problem of biodiversity conservation is becoming more and more acute due to increase of anthropogenic impact. With the evolution of anthropogenic ecosystems, it also increases the vulnerability of species and biodiversity in general, as a result affecting ecological balance and environmental quality. The purpose of the researches was to evaluate the flora and fauna diversity in the Orhei urban ecosystem. The study was conducted during 2017 in 10 urban stations. Floral researches enumerate the presence of 146 species of magnoliophyte plants, grouped in 127 genera from 45 families. The most numerous were the species of the families: Asteraceae, Fabaceae, Rosaceae and Poaceae. The most frequents species are the eurybionte with wide ecological amplitude, some of which are included in the invasive species category. Vertebrates researches have revealed the fact, that the mammal fauna includes 29 species with a higher effective in the green areas of the urban ecosystem. The birds population of the ecosystem enumerate 58 species, prevail those from order Passeriformes.
4

Yarema, O. M., L. Ya Fedonyuk, E. I. Skyba e A. Lesniak-Mochuk. "ANTHROPOGENIC ENVIRONMENTAL CHANGES DUE TO ACCUMULATION OF SOLID HOUSEHOLD WASTE IN TERNOPIL REGION (UKRAINE)". In SAKHAROV READINGS 2021: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY. International Sakharov Environmental Institute of Belarusian State University, 2021. http://dx.doi.org/10.46646/sakh-2021-2-382-386.

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All over the world, the recycling and disposal of household waste are becoming an increasingly pressing issue. In the process of economic development of virgin lands, there was gradual destruction of natural ecosystems and their replacement by anthropogenic ones, the balance between certain species of flora and fauna was disturbed. This undesirable impact of labor on nature is especially evident at the present stage of human development, which is characterized by extremely rapid demographic growth and rapid scientific, technological, and socio-economic development of society. Population growth contributes to the growth of waste - substances, materials, and objects generated in the process of human activity, and have no further use at the place of formation or detection.
5

Vasyukova, A. T., D. A. Tikhonov, R. A. Edwards, M. V. Vasyukov e Talbi Mounir. "Macro- and microelements in new products for the population of ecological territories at risk". In III All-Russian Scientific Conference with International Participation "Science, technology, society: Environmental engineering for sustainable development of territories". Krasnoyarsk Science and Technology City Hall, 2022. http://dx.doi.org/10.47813/nto.3.2022.6.617-621.

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Reduction of deficiency of macro- and microelements in foodstuffs (in particular, iodine and fluorine) of ecologically impoverished regions is possible in the development of new products. In this regard, dietary supplements have been introduced into the recipes of meat, fish, vegetable, cereal and curd dishes. The combination of the main raw materials and additives, the functional properties of the products have been studied, and the optimal organoleptic, structural-mechanical, and rheological properties have been established. Additive "Mobi-lux Universal", containing heme iron, organic calcium and iodine, enrich a wide group of products with minerals by creating protein-vegetable combined compositions. Recipes have been developed and technologies have been substantiated for “Morskie” fish cakes, “Pikantny” meat steak, “Raduzhny” fruit and curd dessert, fruit mousses, and “Appetitnaya” rice casserole with apples. The results of a study of the nutritional value of specialized food products based on meat, fish, vegetable, fruit, cereal products and cottage cheese, enriched with the Mobi-lux Universal complex functional additive, vegetable and fruit powders, are presented. More than 20 dishes have been developed and included in corrective diets for schoolchildren. It has been established that the maximum enrichment of meat and fish products is carried out with vitamins: Betacarotene, B6, B12, as well as macro- and microelements: iron, iodine, calcium, sodium, magnesium and fluorine. Protein-containing fish and meat dishes, due to the included additive, make up for 15% of the daily deficiency in these nutrients (iodine, calcium and iron). Dessert, mousse and casserole - to dishes-sources of bio-organic iodine, calcium and iron. This will fully balance the diet of students in the category of 7-11 years old. The developed dishes were tested in the production conditions of catering establishments of educational organizations.
6

Liu, Keshun. "Improving and developing sustainable methods for plant protein processing". In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/derd4161.

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Sustainability is the balance among environment, equity, and economy. We practice it to support ecological, human, and economic health and vitality, and to meet our own needs without compromising the ability of future generations to meet their own needs. With growing world population, widening gap between developed and developing economies, depleting natural resources, and devastating climate change, there is an urgent need for individuals, corporations, and governmental bodies to do more on sustainability. As oil chemists, we can all play important roles by choosing, selecting, and/or developing sustainable methods to process plant proteins into food or feed. Once these methods are adopted or used by others, a ripple effect is created, where an individual effort is transformed into the effort of a large community or even at an industrial level. Although there are many innovative ways to achieve sustainability when oil chemists are at work, reducing uses of chemicals and natural resources (water, energy, etc.) and cost, and generating less or no wastes are the key strategies. In this presentation, I discuss three processing methods I improved, contributed, or developed during last two decades, to illustrate how an individual chemist can contribute to sustainability. The methods to be discussed include a method for making plant-based meat analogs which has been commercialized, a method for producing soft and water-stable aquafeed, which serves as a promising strategy to mitigate water pollution associated with aquaculture, and a low-resource method for making soy protein concentrate, which is being evaluated at Soybean Innovation Lab for fighting malnutrition in Sub-Saharan Africa. Hopefully, we all can make efforts to provide sufficient proteins to all people regardless of their social and economic levels, while maintaining sustainability for benefiting current and future generations.
7

Oktan, Ercan, e Aysen Kalender. "Suggestions on Preventing Deforestation and Erosion due to Global Climate Change in Türkiye". In 3rd International Congress on Engineering and Life Science. Prensip Publishing, 2023. http://dx.doi.org/10.61326/icelis.2023.35.

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The rapid increase in the world's population from the past to the present has led to an increase in the demand for natural resources, resulting in the deterioration of the forest ecosystem and the emergence of many problems such as global warming. During this period, the changes brought by the industrial revolution have caused an increase in the amount of carbon dioxide (CO2) released into the atmosphere by adversely affecting the ecological balance. The role of forest ecosystems will increase in order to eliminate the negativities caused by the continuous increase in the amount of carbon dioxide (CO2) in the atmosphere and climate change. Within terrestrial ecosystems, soil and vegetation hold and store carbon. Forests, meadows, pastures and agricultural areas constitute the part kept in vegetation. Some of the most important factors affecting the amount and duration of carbon sequestered in terrestrial ecosystems are climate, vegetation type, soil properties, erosion, bedrock and land use changes. As a matter of fact, these changes in land use have triggered desertification, dryness and erosion along with soil losses. In particular, soils transported by erosion are a great loss for nature and cause disruption of the ecological balance. Therefore, in order to maintain this balance, the natural species in the region should be protected and a forest ecosystem consisting of natural species should be created. In this case, we need to understand forest ecosystems very well and to correctly identify the silvicultural interventions that can be applied. In this study, it was aimed to create a road map for silvicultural interventions that can be applied by evaluating carbon losses in areas where desertification, drought and erosion occur in Türkiye. In addition, in line with this road map, general recommendations that are thought to be useful in preventing and combating carbon losses are given.
8

Hasanova, Aytakin. "PREDICTIVE GENETIC SCREENING". In The First International Scientific-Practical Conference- “Modern Tendencies of Dialogue in Multidenominational Society: philosophical, religious, legal view”. IRETC MTÜ, 2020. http://dx.doi.org/10.36962/mtdms202029.

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Human, as a species, is very variable, and his variability is at the basis of his social organization. This variability is maintained, in part, by the chance effects of gene assortment and the variation in these genes is the result of mutations in the past. If our remote ancestors had not mutated we would not he here; further, since no species is likely to he able to reduce its mutation rate substantially by the sort of selection to which it is exposed, we may regard mutations of recent origin as part of the price of having evolved. We are here: all of us have some imperfections we would wish not to have, and many of us are seriously incommoded by poor sight, hearing or thinking. Others among us suffer from some malformation due to faulty development. A few are formed lacking some essential substance necessary to metabolize a normal diet, to clot the blood, or to darken the back of the eye. We will all die and our deaths will normally be related to some variation in our immu-nological defences, in our ability to maintain our arteries free from occlusion, or in some other physiological aptitude. This massive variation, which is the consequence both of chance in the distribution of alleles and variety in the alleles themselves, imposes severe disabilities and handicaps on a substantial proportion of our population. The prospects of reducing this burden by artificial selection from counsel¬ling or selective feticide will be considered and some numerical estimates made of its efficiency and efficacy. Screening is a procedure by which populations are separated into groups, and is widely used for administrative and other purposes. At birth all babies are sexed and divided into two groups. Later the educable majority is selected from the ineducable minority; later still screening continues for both administrative and medical purposes. Any procedure by which populations are sifted into distinct groups is a form of screening, the word being derived from the coarse filter used to separate earth and stones. In medicine its essential features are that the population to be screen¬ed is not knowingly in need of medical attention and the action is taken on behalf of this population for its essential good. A simple example is provided by cervical smear examination, the necessary rationale for which must be the haimless and reliable detection of precancerous changes which can be prevented from becoming irreversible. Any rational decision on the development of such a service must be based on a balance of good and harm and any question of priorities in relation to other services must be based on costing. The balance of good and harm is a value judgement of some complexity. In the example of cervical smears anxiety and the consequences of the occasional removal of a healthy uterus must be weighed against the benefits of the complete removal of a cancerous one, and such matters cannot be costed in monetary terms. In fact, even such an apparently simple procedure as cervical screening is full of unknowns and many of these unknowns can only be resolved by extensive and properly designed studies. In genetic screening the matter is even more complicated, since the screening is often vicarious; that is, one person is screened in order to make a prediction on what may happen to someone else, usually their children, who may be un¬conceived or unborn. Further, the action of such screening may not be designed to ameliorate disease, but to eliminate a fetus which has a high chance of an affliction, or to prevent a marriage in which there is a mutual predisposition to producing abnormal children. These considerations impose very considerable dif¬ferences, since the relative values placed on marriage, on having children within marriage, and on inducing abortion, vary widely between individuals and between societies.
9

Belin, D., D. Baccino, A. Wohlwend, A. Estreicher, J. Hurate e J.-D. Vassalli. "A CELLULAR RECEPTOR FOR UROKINASE-TYPE PLASMINOGEN ACTIVATOR". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642957.

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Recent cell biological and biochemical studies on the urokinase-type plasminogen activator (u-PA) have revealed an unsuspected property of this protein: it binds with high affinity and specificity to the plasma membrane of a number of cell types. Hence, while the interaction of tissue-type plasminogen activator (t-PA) with fibrin suggests a preferred role for this enzyme in the maintenance of fluidity of the extracellular milieu, the cellular binding of u-PA results in the focalisation of plasmin generation to the close environment of the cell surface; this appears as an optimal configuration if u-PA is to participate in the enzymatic events required for cell migration.The available information on the cellular binding of u-PA can be summarized as follows:1. Human monocytes-macrophages, monocyte-like cell lines, fibroblasts, and a variety of other cell lines all express u-PA binding sites. The number of u-PA binding sites on a given cell type may vary as a function of the functional state of the cells. In some cases all sites are occupied by “endogenous” u-PA.2. Binding does not require u-PA activity, and prou-PA binds with the same affinity as does the active enzyme.3. The Kd for u-PA binding is between 1 and 10×10-10 M. The binding site appears to be specific for u-PA.4. Binding requires the presence of the A chain of u-PA; the growth factor module of the A chain is involved in this interaction.5. Bound enzyme does not dissociate readily, nor is it rapidly endocytosed; most importantly, it retains catalytic activity.Studies in progress are aimed at further defining the u-PA determinants responsible for binding. In this context it is noteworthy that there is a tight species specificity of binding: human and murine u-PA, for instance, bind only to cells of the homologous species. Characterization of the u-PA binding site suggests that it is an integral membrane protein that includes at least one Mf 50.000 polypeptide chain.In addition to allowing for the peri-cellular focalisation of u-PA catalysed proteolysis, expression of the u-PA binding site provides a mecanism whereby one cell type can acquire membrane-bound u-PA activity following secretion of the (pro)enzyme by another cell population. A striking example of this is the binding of u-PA, synthesized by the epithelial layer of the male genital tract, to the head region of murine spermatozoa.
10

Ito, Miu, e Yuichi Sugai. "Study on Enhanced Oil Recovery Using Microorganism Generating Foam in Presence of Nanobubbles". In SPE/IATMI Asia Pacific Oil & Gas Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/205671-ms.

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Abstract Both high cost and environmental load of surfactant are issues to be solved in foam EOR. Moreover, it is difficult to control the injection of surfactant and gas so that the foam is generated in only high permeable zones selectively in oil reservoir. The authors have found a foam generating microorganism and hit upon an idea of the microbial foam EOR which makes the microorganism do generating foam in oil reservoir. The mechanism of the microbial foam generation and culture condition suitable for the foam generation were studied in this study. A species of Pseudomonas aeruginosa was used as a foam producer in this study. It was cultured in the medium consisting of glucose and eight kinds of minerals at 30 °C and atmospheric pressure under anaerobic conditions. Because P. aeruginosa generally grows better under aerobic conditions, the microorganism was supplied with oxygen nanobubbles as the oxygen source. The carbon dioxide nanobubbles were also used as a comparison target in this study. The state of foam generation in the culture solution was observed during the cultivation. The surface tension, surfactant concentration, protein concentration, polysaccharides concentration and bacterial population of the culture solution were measured respectively. The foam was started to be generated by the microorganism after 2 days of cultivation and its volume became maximum after 3 days of cultivation. The foam generation was found in the culture solution which contained both oxygen nanobubbles and carbon dioxide nanobubbles whereas little foam was found in non-nanobubbles culture solution. The foam generation found in the culture solution containing carbon dioxide nanobubbles was more than that in the culture solution containing oxygen nanobubbles. Both gas and protein concentration increased along with the formation of the foam whereas surfactant and polysaccharides were not increased, therefore, the foam was assumed to be generated with gas and protein which were generated by P. aeruginosa. It was found that the carbon dioxide nanobubbles were positively charged in the culture medium whereas they were negatively charged in tap water through the measurement of zeta potential of nanobubbles, therefore, the carbon dioxide nanobubbles attracted cations in the culture medium and became positively charged. Positively charged carbon dioxide nanobubbles transported cations to the microbial cells of P. aeruginosa. Among cations in the culture medium, ferrous ions are essential for the protein generation of P. aeruginosa, therefore, the positively charged carbon dioxide nanobubbles attracted ferrous ions and transport them to the microbial cells, resulting the growth and metabolism of P. aeruginosa were activated. Those results suggest that the microbial foam EOR can be materialized by supplying the microorganism with carbon dioxide nanobubbles or ferrous ions.

Rapporti di organizzazioni sul tema "Population balance of protein species":

1

Feldman, Moshe, Eitan Millet, Calvin O. Qualset e Patrick E. McGuire. Mapping and Tagging by DNA Markers of Wild Emmer Alleles that Improve Quantitative Traits in Common Wheat. United States Department of Agriculture, febbraio 2001. http://dx.doi.org/10.32747/2001.7573081.bard.

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The general goal was to identify, map, and tag, with DNA markers, segments of chromosomes of a wild species (wild emmer wheat, the progenitor of cultivated wheat) determining the number, chromosomal locations, interactions, and effects of genes that control quantitative traits when transferred to a cultivated plant (bread wheat). Slight modifications were introduced and not all objectives could be completed within the human and financial resources available, as noted with the specific objectives listed below: 1. To identify the genetic contribution of each of the available wild emmer chromosome-arm substitution lines (CASLs) in the bread wheat cultivar Bethlehem for quantitative traits, including grain yield and its components and grain protein concentration and yield, and the effect of major loci affecting the quality of end-use products. [The quality of end-use products was not analyzed.] 2. To determine the extent and nature of genetic interactions (epistatic effects) between and within homoeologous groups 1 and 7 for the chromosome arms carrying "wild" and "cultivated" alleles as expressed in grain and protein yields and other quantitative traits. [Two experiments were successful, grain protein concentration could not be measured; data are partially analyzed.] 3. To derive recombinant substitution lines (RSLs) for the chromosome arms of homoeologous groups 1 and 7 that were found previously to promote grain and protein yields of cultivated wheat. [The selection of groups 1 and 7 tons based on grain yield in pot experiments. After project began, it was decided also to derive RSLs for the available arms of homoeologous group 4 (4AS and 4BL), based on the apparent importance of chromosome group 4, based on early field trials of the CASLs.] 4. To characterize the RSLs for quantitative traits as in objective 1 and map and tag chromosome segments producing significant effects (quantitative trait loci, QTLs by RFLP markers. [Producing a large population of RSLs for each chromosome arm and mapping them proved more difficult than anticipated, low numbers of RSLs were obtained for two of the chromosome arms.] 5. To construct recombination genetic maps of chromosomes of homoeologous groups 1 and 7 and to compare them to existing maps of wheat and other cereals [Genetic maps are not complete for homoeologous groups 4 and 7.] The rationale for this project is that wild species have characteristics that would be valuable if transferred to a crop plant. We demonstrated the sequence of chromosome manipulations and genetic tests needed to confirm this potential value and enhance transfer. This research has shown that a wild tetraploid species harbors genetic variability for quantitative traits that is interactive and not simply additive when introduced into a common genetic background. Chromosomal segments from several chromosome arms improve yield and protein in wheat but their effect is presumably enhanced when combination of genes from several segments are integrated into a single genotype in order to achieve the benefits of genes from the wild species. The interaction between these genes and those in the recipient species must be accounted for. The results of this study provide a scientific basis for some of the disappointing results that have historically obtained when using wild species as donors for crop improvement and provide a strategy for further successes.
2

Grumet, R., J. Burger, Y. Tadmor, A. Gur, C. Barry, A. Schäffer e M. Petreikov. Cucumis fruit surface biology: Genetic analysis of fruit exocarp features in melon (C. melo) and cucumber (C. sativus). Israel: United States-Israel Binational Agricultural Research and Development Fund, 2020. http://dx.doi.org/10.32747/2020.8134155.bard.

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The fruit surface (exocarp) is a unique tissue with multiple roles influencing fruit growth and development, disease susceptibility, crop yield, post-harvest treatments, shipping and storage quality, and food safety. Furthermore, highly visible exocarp traits are the consumer's first exposure to the fruit, serving to identify fruit type, variety, attractiveness, and market value. Cucurbit fruit, including the closely related Cucumis species, melon (C. melo) and cucumber (C. sativus), exhibit tremendous diversity for fruit surface properties that are not present in model species. In this project, we identified genetic factors influencing Cucumis fruit surface morphology with respect to important quality determinants such as exocarp and flesh color, cuticle deposition, and surface netting. We employed a combination of approaches including: genome-wide association studies (GWAS) utilizing an extensive melon population and the U.S. Plant Introduction (PI) collection for cucumber to identify genomic regions associated with natural variation in fruit surface traits; bulked segregant RNA-seq (BSR-seq) analysis of bi-parental F2:3 or RIL (recombinant inbred line) populations to genomic regions and candidate genes segregating for fruit surface traits; and comparison of syntenic genomic regions and identification of homologous candidate genes. Candidate genes were examined for sequence and/or expression differences during fruit development that correspond with phenotypic differences. Primary outcomes of the work included identification of candidate genes influencing cuticle deposition, epidermal cell structure, surface netting, and intensity of rind and flesh color. Parallel studies identified mutations within the cucumber and melon homologs of the transcription factor WIN1 (WAX INDUCER1) as a significant factor influencing these surface properties. Additional QTL (quantitative trait loci) were identified in both species, and candidate genes in melon include a novel beta-glucosidase involved in lignin production and an integral membrane protein potentially involved in cuticle metabolism. Genetic resources and biochemical approaches have been developed to study cuticle and wax deposition in both species: segregating populations of melon were developed and sequenced for bulked segregant analysis and samples collected for metabolic analysis; an isolation procedure was developed for lipid droplets from cucumber peel and metabolomic analyses have been initiated. Genetic studies in melon identified mutations in a candidate gene (APRR2), associated with light immature rind, and further indicated that this gene is also associated with color intensity of both mature rinds and flesh, making it a good target for breeding. GWAS studies utilizing the cucumber core diversity population are being performed to identify additional sources of variation for fruit surface properties, map QTL, and examine for synteny with melon. Collectively these studies identified genetic regions associated with important quality traits and contributed to our understanding of underlying biological processes associated with fruit surface development. Knowledge of genetic control of these characteristics can facilitate more efficient breeding for important fruit surface traits.
3

Fridman, Eyal, e Eran Pichersky. Tomato Natural Insecticides: Elucidation of the Complex Pathway of Methylketone Biosynthesis. United States Department of Agriculture, dicembre 2009. http://dx.doi.org/10.32747/2009.7696543.bard.

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Plant species synthesize a multitude of specialized compounds 10 help ward off pests. and these in turn may well serve as an alternative to synthetic pesticides to reduce environmental damage and health risks to humans. The general goal of this research was to perform a genetic and biochemical dissection of the natural-insecticides methylketone pathway that is specific to the glandular trichomes of the wild species of tomato, Solanumhabrochaites f. glabratum (accession PI126449). Previous study conducted by us have demonstrated that these compounds are synthesized de novo as a derivate pathway of the fatty acid biosynthesis, and that a key enzyme. designated MethylketoneSynthase 1 (MKS 1). catalyzes conversion of the intermediate B-ketoacyl- ACPs to the corresponding Cn-1 methylketones. The approach taken in this proposed project was to use an interspecific F2 population. derived from the cross between the cultivated lV182 and the wild species PIl26449. for three objectives: (i) Analyze the association between allelic status of candidate genes from the fatty acid biosynthesis pathway with the methylketone content in the leaves (ii) Perform bulk segregant analysis of genetic markers along the tomato genome for identifying genomic regions that harbor QTLs for 2TD content (iii) Apply differential gene expression analysis using the isolated glands of bulk segregant for identifying new genes that are involved in the pathway. The genetic mapping in the interspecific F2 population included app. 60 genetic markers, including the candidate genes from the FAS pathway and SSR markers spread evenly across the genome. This initial; screening identified 5 loci associated with MK content including the candidate genes MKS1, ACC and MaCoA:ACP trans. Interesting observation in this genetic analysis was the connection between shape and content of the glands, i.e. the globularity of the four cells, typical to the wild species. was associated with increased MK in the segregating population. In the next step of the research transcriptomic analysis of trichomes from high- and 10w-MK plants was conducted. This analysis identified a new gene, Methy1ketone synthase 2 (MKS2), whose protein product share sequence similarity to the thioesterase super family of hot-dog enzymes. Genetic analysis in the segregating population confirmed its association with MK content, as well as its overexpression in E. coli that led to formation of MK in the media. There are several conclusions drawn from this research project: (i) the genetic control of MK accumulation in the trichomes is composed of biochemical components in the FAS pathway and its vicinity (MKS 1 and MKS2). as well as genetic factors that mediate the morphology of these specialized cells. (ii) the biochemical pathway is now realized different from what was hypothesized before with MKS2 working upstream to I\1KS 1 and serves as the interface between primary (fatty acids) and secondary (MK) metabolism. We are currently testing the possible physical interactions between these two proteins in vitro after the genetic analysis showed clear epistatic interactions. (iii) the regulation of the pathway that lead to specialized metabolism in the wild species is largely mediated by transcription and one of the achievements of this project is that we were able to isolate and verify the specificity of the MKS1 promoter to the trichomes which allows manipulation of the pathways in these cells (currently in progress). The scientific implications of this research project is the advancement in our knowledge of hitherto unknown biochemical pathway in plants and new leads for studying a new family in plants (hot dog thioesterase). The agricultural and biotechnological implication are : (i) generation of new genetic markers that could assist in importing this pathway to cultivated tomato hence enhancing its natural resistance to insecticides, (ii) the discovery of MKS2 adds a new gene for genetic engineering of plants for making new fatty acid derived compounds. This could be assisted with the use of the isolated and verified MKS1 promoter. The results of this research were summarized to a manuscript that was published in Plant Physiology (cover paper). to a chapter in a proceeding book. and one patent was submitted in the US.
4

Li, Li, Joseph Burger, Nurit Katzir, Yaakov Tadmor, Ari Schaffer e Zhangjun Fei. Characterization of the Or regulatory network in melon for carotenoid biofortification in food crops. United States Department of Agriculture, aprile 2015. http://dx.doi.org/10.32747/2015.7594408.bard.

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The general goals of the BARD research grant US-4423-11 are to understand how Or regulates carotenoid accumulation and to reveal novel strategies for breeding agricultural crops with enhanced β-carotene level. The original objectives are: 1) to identify the genes and proteins in the Or regulatory network in melon; 2) to genetically and molecularly characterize the candidate genes; and 3) to define genetic and functional allelic variation of these genes in a representative germplasm collection of the C. melo species. Or was found by the US group to causes provitamin A accumulation in chromoplasts in cauliflower. Preliminary genetic study from the Israeli group revealed that the melon Or gene (CmOr) completely co-segregated with fruit flesh color in a segregating mapping population and in a wide melon germplasm collection, which set the stage for the funded research. Major conclusions and achievements include: 1). CmOris proved to be the gene that controls melon fruit flesh color and represents the previously described gflocus in melon. 2). Genetic and molecular analyses of CmOridentify and confirm a single SNP that is responsible for the orange and non-orange phenotypes in melon fruit. 3). Alteration of the evolutionarily conserved arginine in an OR protein to both histidine or alanine greatly enhances its ability to promote carotenoid accumulation. 4). OR promotes massive carotenoid accumulation due to its dual functions in regulating both chromoplast biogenesis and carotenoid biosynthesis. 5). A bulk segregant transcriptome (BSRseq) analysis identifies a list of genes associated with the CmOrregulatory network. 6). BSRseq is proved to be an effective approach for gene discovery. 7). Screening of an EMS mutation library identifies a low β mutant, which contains low level of carotenoids due to a mutation in CmOrto produce a truncated form of OR protein. 8). low β exhibits lower germination rate and slow growth under salt stress condition. 9). Postharvest storage of fruit enhances carotenoid accumulation, which is associated with chromoplast development. Our research uncovers the molecular mechanisms underlying the Or-regulated high level of carotenoid accumulation via regulating carotenoidbiosynthetic capacity and storage sink strength. The findings provide mechanistic insights into how carotenoid accumulation is controlled in plants. Our research also provides general and reliable molecular markers for melon-breeding programs to select orange varieties, and offers effective genetic tools for pro-vitamin A enrichment in other important crops via the rapidly developed genome editing technology. The newly discovered low β mutant could lead to a better understanding of the Or gene function and its association with stress response, which may explain the high conservation of the Or gene among various plant species.
5

Landau, Sergei Yan, John W. Walker, Avi Perevolotsky, Eugene D. Ungar, Butch Taylor e Daniel Waldron. Goats for maximal efficacy of brush control. United States Department of Agriculture, marzo 2008. http://dx.doi.org/10.32747/2008.7587731.bard.

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Background. Brush encroachment constitutes a serious problem in both Texas and Israel. We addressed the issue of efficacy of livestock herbivory - in the form of goat browsing - to change the ecological balance to the detriment of the shrub vegetation. Shrub consumption by goats is kept low by plant chemical defenses such as tannins and terpenes. Scientists at TAES and ARO have developed an innovative, cost-effective methodology using fecal Near Infrared Spectrometry to elucidate the dietary percentage of targeted, browse species (terpene-richredberry and blueberry juniper in the US, and tannin-rich Pistacialentiscus in Israel) for a large number of animals. The original research objectives of this project were: 1. to clarify the relative preference of goat breeds and the individual variation of goats within breeds, when consuming targeted brush species; 2. to assess the heritability of browse intake and validate the concept of breeding goat lines that exhibit high preference for chemically defended brush, using juniper as a model; 3. to clarify the relative contributions of genetics and learning on the preference for target species; 4. to identify mechanisms that are associated with greater intake of brush from the two target species; 5. to establish when the target species are the most vulnerable to grazing. (Issue no.5 was addressed only partly.) Major conclusions, solutions, achievements: Both the Israel and US scientists put significant efforts into improving and validating the technique of Fecal NIRS for predicting the botanical composition of goat diets. Israeli scientists validated the use of observational data for calibrating fecal NIRS, while US scientists established that calibrations could be used across animals differing in breed and age but that caution should be used in making comparisons between different sexes. These findings are important because the ability to select goat breeds or individuals within a breed for maximal efficiency of brush control is dependent upon accurate measurement of the botanical composition of the diet. In Israel it was found that Damascus goats consume diets more than twice richer in P. lentiscus than Mamber or Boer goats. In the US no differences were found between Angora and Boer cross goats but significant differences were found between individuals within breeds in juniper dietary percentage. In both countries, intervention strategies were found that further increased the consumption of the chemically defended plant. In Israel feeding polyethylene glycol (PEG, MW 4,000) that forms high-affinity complexes with tannins increased P. lentiscus dietary percentage an average of 7 percentage units. In the US feeding a protein supplement, which enhances rates of P450-catalyzed oxidations and therefore the rate of oxidation of monoterpenes, increased juniper consumption 5 percentage units. However, the effects of these interventions were not as large as breed or individual animal effects. Also, in a wide array of competitive tannin-binding assays in Israel with trypsin, salivary proteins did not bind more tannic acid or quebracho tannin than non-specific bovine serum albumin, parotid saliva did not bind more tannins than mixed saliva, no response of tannin-binding was found to levels of dietary tannins, and the breed effect was of minor importance, if any. These fundings strongly suggest that salivary proteins are not the first line of defense from tannin astringency in goats. In the US relatively low values for heritability and repeatability for juniper consumption were found (13% and 30%, respectively), possibly resulting from sampling error or non-genetic transfer of foraging behavior, i.e., social learning. Both alternatives seem to be true as significant variation between sequential observations were noted on the same animal and cross fostering studies conducted in Israel demonstrated that kids raised by Mamber goats showed lower propensity to consume P. lentiscus than counterparts raised by Damascus goats.
6

Needham, Glenn R., Uri Gerson, Gloria DeGrandi-Hoffman, D. Samatero, J. Yoder e William Bruce. Integrated Management of Tracheal Mite, Acarapis woodi, and of Varroa Mite, Varroa jacobsoni, Major Pests of Honey Bees. United States Department of Agriculture, marzo 2000. http://dx.doi.org/10.32747/2000.7573068.bard.

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Objectives: The Israeli work plan regarding HBTM included: (a) producing a better diagnostic method; (b) following infestations during the season and evaluating damage to resistant bees and, (c) controlling HBTM by conventional means under local conditions. For varroa our plans to try novel control (e.g. oil novel control (e.g. oil patties & essential oils) were initially delayed by very low pest populations, then disrupted by the emergence of fluvalinate resistance. We monitored the spread of resistance to understand it better, and analyzed an underlying biochemical resistance mechanism in varroa. The US work plan focused on novel management methods for both mites with an emphasis on reducing use of traditional insecticides due to resistance and contamination issues. Objectives were: (a) evaluating plant essential oils for varroa control; (b) exploring the vulnerability of varroa to desiccation for their management; and (c) looking for biological variation in HBTM that could explain virulence variability between colonies. Although the initial PI at the USDA Beltsville Bee Lab, W.A. Bruce, retired during the project we made significant strides especially on varroa water balance. Subcontracts were performed by Yoder (Illinois College) on varroa water balance and DeGrandi-Hoffman (USDA) who evaluated plant essential oils for their potential to control varroa. We devised an IPM strategy for mite control i the U.S. Background: Mites that parasitize honey bees are a global problem. They are threatening the survival of managed and feral bees, the well-being of commercial/hobby beekeeping, and due to pollination, the future of some agricultural commodities is threatened. Specific economic consequences of these mites are that: (a) apiculture/breeder business are failing; (b) fewer colonies exist; (c) demand and cost for hive leasing are growing; (d) incidences of bee pathogens are increasing; and, (e) there are ore problems with commercial-reared bees. As a reflection of the continued significance f bee mites, a mite book is now in press (Webster & delaplane, 2000); and the 2nd International Conference on Africanized Honey Bees and Bee Mites is scheduled (April, 2000, Arizona). The first such conference was at OSU (1987, GRN was co-organizer). The major challenge is controlling two very different mites within a colony while not adversely impacting the hive. Colony management practices vary, as do the laws dictating acaricide use. Our basic postulates were that: (a) both mites are of economic importance with moderate to high infestations but not at low rates and, (b) once established they will not be eradicated. A novel strategy was devised that deals with the pests concomitantly by maintaining populations at low levels, without unnecessary recourse to synthetic acaricides. Major Conclusions, Solutions, Achievements: A major recent revelation is that there are several species of "Varroa jacobsoni" (Anderson & Trueman 1999). Work on control, resistance, population dynamics, and virulence awaits knowing whether this is a problem. In the U.S. there was no difference between varroa from three locales in terms of water balance parameters (AZ, MN & PA), which bodes well for our work to date. Winter varroa (U.S.) were more prone to desiccation than during other seasons. Varroa sensitivity to desiccation has important implications for improving IPM. Several botanicals showed some promise for varroa control (thymol & origanum). Unfortunately there is varroa resistance to Apistan in Israel but a resistance mechanism was detected for the first time. The Israel team also has a new method for HBTM diagnosis. Annual tracheal mite population trends in Israel were characterized, which will help in targeting treatment. Effects of HBTM on honey yields were shown. HBTM control by Amitraz was demonstrated for at least 6 months. Showing partial resistance by Buckfast bees to HBTM will be an important IPM tactic in Israel and U.S.
7

Elizur, Abigail, Amir Sagi, Gideon Hulata, Clive Jones e Wayne Knibb. Improving Crustacean Aquaculture Production Efficiencies through Development of Monosex Populations Using Endocrine and Molecular Manipulations. United States Department of Agriculture, giugno 2010. http://dx.doi.org/10.32747/2010.7613890.bard.

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Background Most of Australian prawn aquaculture production is based on P. monodon. However, the Australian industry is under intense competition from lower priced overseas imports. The availability of all-female monosex populations, by virtue of their large size and associated premium prize, will offer competitive advantage to the industry which desperately needs to counteract competitors within this market. As for the redclaw production in Israel, although it is at its infancy, the growers realized that the production of males is extremely advantageous and that such management strategy will change the economic assumptions and performances of this aquaculture to attract many more growers. Original objectives (as in original proposal) Investigating the sex inheritance mechanism in the tiger prawn. Identification of genes expressed uniquely in the androgenic gland (AG) of prawns and crayfish. The above genes and/or their products will be used to localize the AG in the prawn and manipulate the AG activity in both species. Production of monosex populations through AG manipulation. In the prawn, production of all-female populations and in the crayfish, all-male populations. Achievements In the crayfish, the AG cDNA library was further screened and a third AG specific transcript, designated Cq-AG3, had been identified. Simultaneously the two AG specific genes, which were previously identified, were further characterized. Tissue specificity of one of those genes, termed Cq-AG2, was demonstrated by northern blot hybridization and RNA in-situ hybridization. Bioinformatics prediction, which suggested a 42 amino acid long signal anchor at the N-terminus of the deduced Cq-AG2, was confirmed by immunolocalization of a recombinant protein. Cq-IAG's functionality was demonstrated by dsRNA in-vivo injections to intersex crayfish. Cq-IAGsilencing induced dramatic sex-related alterations, including male feature feminization, reduced sperm production, extensive testicular apoptosis, induction of the vitellogeningene expression and accumulation of yolk proteins in the ovaries. In the prawn, the AG was identified and a cDNA library was created. The putative P. monodonAG hormone encoding gene (Pm-IAG) was identified, isolated and characterized for time of expression and histological localization. Implantation of the AG into prawn post larvae (PL) and juveniles resulted in phenotypic transformation which included the appearance of appendix masculina and enlarged petasma. The transformation however did not result in sex change or the creation of neo males thus the population genetics stage to be executed with Prof. Hulata did not materialized. Repeated AG implantation is currently being trialed. Major conclusions and Implications, both scientific and agricultural Cq-IAG's involvement in male sexual differentiation had been demonstrated and it is strongly suggested that this gene encodes an AG hormone in this crayfish. A thorough screening of the AG cDNA library shows Cq-IAG is the prominent transcript within the library. However, the identification of two additional transcripts hints that Cq-IAG is not the only gene mediating the AG effects. The successful gene silencing of Cq-IAG, if performed at earlier developmental stages, might accomplish full and functional sex reversal which will enable the production of all-male crayfish populations. Pm-IAG is likely to play a similar role in prawns. It is possible that repeated administration of the AG into prawn will lead to the desired full sex reversal, so that WZ neo males, crossed with WZ females can result in WW females, which will form the basis for monosex all-female population.
8

Meidan, Rina, e Robert Milvae. Regulation of Bovine Corpus Luteum Function. United States Department of Agriculture, marzo 1995. http://dx.doi.org/10.32747/1995.7604935.bard.

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The main goal of this research plan was to elucidate regulatory mechanisms controlling the development, function of the bovine corpus luteum (CL). The CL contains two different sterodigenic cell types and therefore it was necessary to obtain pure cell population. A system was developed in which granulosa and theca interna cells, isolated from a preovulatory follicle, acquired characteristics typical of large (LL) and small (SL) luteal cells, respectively, as judged by several biochemical and morphological criteria. Experiments were conducted to determine the effects of granulosa cells removal on subsequent CL function, the results obtained support the concept that granulosa cells make a substaintial contribution to the output of progesterone by the cyclic CL but may have a limited role in determining the functional lifespan of the CL. This experimental model was also used to better understand the contribution of follicular granulosa cells to subsequent luteal SCC mRNA expression. The mitochondrial cytochrome side-chain cleavage enzyme (SCC), which converts cholesterol to pregnenolone, is the first and rate-limiting enzyme of the steroidogenic pathway. Experiments were conducted to characterize the gene expression of P450scc in bovine CL. Levels of P450scc mRNA were higher during mid-luteal phase than in either the early or late luteal phases. PGF 2a injection decreased luteal P450scc mRNA in a time-dependent manner; levels were significantly reduced by 2h after treatment. CLs obtained from heifers on day 8 of the estrous cycle which had granulosa cells removed had a 45% reduction in the levels of mRNA for SCC enzymes as well as a 78% reduction in the numbers of LL cells. To characterize SCC expression in each steroidogenic cell type we utilized pure cell populations. Upon luteinization, LL expressed 2-3 fold higher amounts of both SCC enzymes mRNAs than SL. Moreover, eight days after stimulant removal, LL retained their P4 production capacity, expressed P450scc mRNA and contained this protein. In our attempts to establish the in vitro luteinization model, we had to select the prevulatory and pre-gonadotropin surge follicles. The ratio of estradiol:P4 which is often used was unreliable since P4 levels are high in atretic follicles and also in preovulatory post-gonadotropin follicles. We have therefore examined whether oxytocin (OT) levels in follicular fluids could enhance our ability to correctly and easily define follicular status. Based on E2 and OT concentrations in follicular fluids we could more accurately identify follicles that are preovulatory and post gonadotropin surge. Next we studied OT biosynthesis in granulosa cells, cells which were incubated with forskolin contained stores of the precursor indicating that forskolin (which mimics gonadotropin action) is an effective stimulator of OT biosynthesis and release. While studying in vitro luteinization, we noticed that IGF-I induced effects were not identical to those induced by insulin despite the fact that megadoses of insulin were used. This was the first indication that the cells may secrete IGF binding protein(s) which regonize IGFs and not insulin. In a detailed study involving several techniques, we characterized the species of IGF binding proteins secreted by luteal cells. The effects of exogenous polyunsaturated fatty acids and arachidonic acid on the production of P4 and prostanoids by dispersed bovine luteal cells was examined. The addition of eicosapentaenoic acid and arachidonic acid resulted in a dose-dependent reduction in basal and LH-stimulated biosynthesis of P4 and PGI2 and an increase in production of PGF 2a and 5-HETE production. Indomethacin, an inhibitor of arachidonic acid metabolism via the production of 5-HETE was unaffected. Results of these experiments suggest that the inhibitory effect of arachidonic acid on the biosynthesis of luteal P4 is due to either a direct action of arachidonic acid, or its conversion to 5-HETE via the lipoxgenase pathway of metabolism. The detailed and important information gained by the two labs elucidated the mode of action of factors crucially important to the function of the bovine CL. The data indicate that follicular granulosa cells make a major contribution to numbers of large luteal cells, OT and basal P4 production, as well as the content of cytochrome P450 scc. Granulosa-derived large luteal cells have distinct features: when luteinized, the cell no longer possesses LH receptors, its cAMP response is diminished yet P4 synthesis is sustained. This may imply that maintenance of P4 (even in the absence of a Luteotropic signal) during critical periods such as pregnancy recognition, is dependent on the proper luteinization and function of the large luteal cell.
9

Maycock, Barry, Cath Mulholland, Emma French e Joseph Shavila. Rapid Risk Assessment: What is the risk from microcystins in the edible flesh of fish caught from Lough Neagh? Food Standards Agency, marzo 2024. http://dx.doi.org/10.46756/sci.fsa.slz868.

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During the Summer and Autumn of 2023, Lough Neagh in Northern Ireland was affected by a cyanobacterial bloom. Testing of water from within the bloom reported high concentrations of one type of cyanobacterial toxin, microcystins. Samples were taken from the Lough of eels, roach, perch, pollan and bream and tested for a range of cyanobacterial toxins, including microcystins, nodularins, anatoxin, cylindrospermopsin and saxitoxin. Each sample comprised 10 fish, and five samples were taken of each species, except for bream for which a single sample was collected. The fish were dissected and the edible flesh, intestine, liver, roe, gonad and/or gills analysed separately. Microcystins were detected at a range of concentrations in the various parts of the fish that were sampled - intestine, liver, roe and/or gills, but were not detected in the edible flesh of any of the fish samples. Averaged across the samples, the highest concentrations of microcystins were quantified in the intestine samples, followed by the liver samples, with low concentrations were detected in the gills and a small number of the samples of gonads and roe. None of the other toxins were detected in any fish sample. The initial analysis for microcystins was of free toxins only. However, there is evidence that microcystins which are covalently bound to proteins are also bioavailable and therefore 22 fish tissue samples, including nine fish flesh samples, were also sent to another laboratory where they were analysed by a method which measures the total concentrations of microcystins, free and protein-bound. The viscera tissue samples chosen for the further analysis were those with the highest concentrations of the free toxins, while the fish flesh samples included 2-3 samples each of eels, roach, pollan and perch. The concentrations of total microcystins found in viscera samples were around one order of magnitude higher than the concentrations of free microcystins that had been measured. However, microcystins were still not detected in the edible fish flesh samples. It is possible that microcystins were not present at any level in any of the fish flesh samples. However, the presence of microcystins in the edible flesh of fish has been reported in the scientific literature, albeit at lower levels than those in the gastrointestinal tract or other parts of the viscera such as liver (Testai et al., 2016). Since microcystins were detected in other parts of the fish sampled from Lough Neagh it is also possible that they were also present in the fish flesh but at levels below the limits of detection of the analytical methods. The limit of detection of the analytical method for total (free + bound) microcystins was 10 µg/kg wet weight. An upper bound dietary exposure assessment was conducted. While a lower bound exposure assessment would assume the microcystins were not present in the edible flesh, i.e. a concentration of 0 µg/kg, the upper bound approach assumed they were present at the limit of detection of 10 µg/kg. The true concentrations may be between these levels. The exposure assessments consider high consumers of fish (97.5th percentile). For eels, consumption data were used from the National Diet and Nutrition Survey (NDNS). For roach, perch, pollan and bream. No consumption data were available from the NDNS and consumption data for trout were used instead as a proxy. The main target organ for toxicity of the microcystins is the liver, though other organs may also be affected. The microcystin most studied toxicologically is microcystin-LR, which is one of the most common microcystins. A WHO review established a provisional tolerable daily intake (TDI) for microcystin-LR of 0.04 µg per kg bodyweight (bw). WHO recommended that exposures to total microcystins should be compared to this provisional TDI, though there is uncertainty with this as individual microcystins are likely to differ significantly in their toxic potencies. Estimated dietary exposures of total microcystins were all within the provisional TDI, indicating no health concern from consuming the edible flesh of these species. Since fish may be caught and prepared for consumption not only by food business operators but by recreational anglers, concern has been raised that evisceration may be incomplete or the edible flesh may become contaminated in the process, and therefore this was also considered in the risk assessment. This was based on the sample of fish which contained the highest concentration of total microcystins in a viscera component, which was a sample of roach with a particularly high concentration of microcystins in intestine. It was assumed that 10% of the relative proportion of intestine to flesh in the fish would be inadvertently consumed with the flesh. In this scenario, dietary exposures would be within the provisional TDI in most age groups or would marginally exceed the TDI, but this would not be toxicologically significant. In addition, since this exposure scenario used an upper bound approach to the concentration in flesh, and used the highest concentration in any viscera sample, it is not clear that there would be any exceedance of the provisional TDI in practice. Overall, it appears unlikely that consumers will substantially exceed the provisional TDI on a long-term basis due to incomplete evisceration of fish. Overall, exposure to microcystins from eating the edible flesh of the tested fish species would not be expected to cause adverse effects in consumers, including if the fish is inadequately eviscerated. Therefore, we consider the frequency of adverse reactions in the general population to be negligible, so rare that it does not merit to be included. Based on the possible levels of exposure to microcystins from fish from Lough Neagh, it is considered that any liver injury, were it to occur in consumers of fish, would result from long term exposure and be mild. Overall, we consider the severity of illness that could potentially occur as a result of exposure to microcystins from consuming edible fish flesh from Lough Neagh to be medium (i.e. moderate illness, incapacitating but not usually life-threatening and of moderate duration). We consider the level of uncertainty to be medium (i.e. there are some but no complete data available), but that this does not affect the conclusion of the risk assessment since many of the key uncertainties are addressed within the risk assessment. However, future monitoring would be useful to assess whether microcystin concentrations in the fish change over time.
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Ocampo-Gaviria, José Antonio, Roberto Steiner Sampedro, Mauricio Villamizar Villegas, Bibiana Taboada Arango, Jaime Jaramillo Vallejo, Olga Lucia Acosta-Navarro e Leonardo Villar Gómez. Report of the Board of Directors to the Congress of Colombia - March 2023. Banco de la República de Colombia, giugno 2023. http://dx.doi.org/10.32468/inf-jun-dir-con-rep-eng.03-2023.

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Banco de la República is celebrating its 100th anniversary in 2023. This is a very significant anniversary and one that provides an opportunity to highlight the contribution the Bank has made to the country’s development. Its track record as guarantor of monetary stability has established it as the one independent state institution that generates the greatest confidence among Colombians due to its transparency, management capabilities, and effective compliance with the central banking and cultural responsibilities entrusted to it by the Constitution and the Law. On a date as important as this, the Board of Directors of Banco de la República (BDBR) pays tribute to the generations of governors and officers whose commitment and dedication have contributed to the growth of this institution.1 Banco de la República’s mandate was confirmed in the National Constitutional Assembly of 1991 where the citizens had the opportunity to elect the seventy people who would have the task of drafting a new constitution. The leaders of the three political movements with the most votes were elected as chairs to the Assembly, and this tripartite presidency reflected the plurality and the need for consensus among the different political groups to move the reform forward. Among the issues considered, the National Constitutional Assembly gave special importance to monetary stability. That is why they decided to include central banking and to provide Banco de la República with the necessary autonomy to use the instruments for which they are responsible without interference from other authorities. The constituent members understood that ensuring price stability is a state duty and that the entity responsible for this task must be enshrined in the Constitution and have the technical capability and institutional autonomy necessary to adopt the decisions they deem appropriate to achieve this fundamental objective in coordination with the general economic policy. In particular, Article 373 established that “the State, through Banco de la República, shall ensure the maintenance of the purchasing power of the currency,” a provision that coincided with the central banking system adopted by countries that have been successful in controlling inflation. In 1999, in Ruling 481, the Constitutional Court stated that “the duty to maintain the purchasing power of the currency applies to not only the monetary, credit, and exchange authority, i.e., the Board of Banco de la República, but also those who have responsibilities in the formulation and implementation of the general economic policy of the country” and that “the basic constitutional purpose of Banco de la República is the protection of a sound currency. However, this authority must take the other economic objectives of state intervention such as full employment into consideration in their decisions since these functions must be coordinated with the general economic policy.” The reforms to Banco de la República agreed upon in the Constitutional Assembly of 1991 and in Act 31/1992 can be summarized in the following aspects: i) the Bank was assigned a specific mandate: to maintain the purchasing power of the currency in coordination with the general economic policy; ii) the BDBR was designatedas the monetary, foreign exchange, and credit authority; iii) the Bank and its Board of Directors were granted a significant degree of independence from the government; iv) the Bank was prohibited from granting credit to the private sector except in the case of the financial sector; v) established that in order to grant credit to the government, the unanimous vote of its Board of Directors was required except in the case of open market transactions; vi) determined that the legislature may, in no case, order credit quotas in favor of the State or individuals; vii) Congress was appointed, on behalf of society, as the main addressee of the Bank’s reporting exercise; and viii) the responsibility for inspection, surveillance, and control over Banco de la República was delegated to the President of the Republic. The members of the National Constitutional Assembly clearly understood that the benefits of low and stable inflation extend to the whole of society and contribute mto the smooth functioning of the economic system. Among the most important of these is that low inflation promotes the efficient use of productive resources by allowing relative prices to better guide the allocation of resources since this promotes economic growth and increases the welfare of the population. Likewise, low inflation reduces uncertainty about the expected return on investment and future asset prices. This increases the confidence of economic agents, facilitates long-term financing, and stimulates investment. Since the low-income population is unable to protect itself from inflation by diversifying its assets, and a high proportion of its income is concentrated in the purchase of food and other basic goods that are generally the most affected by inflationary shocks, low inflation avoids arbitrary redistribution of income and wealth.2 Moreover, low inflation facilitates wage negotiations, creates a good labor climate, and reduces the volatility of employment levels. Finally, low inflation helps to make the tax system more transparent and equitable by avoiding the distortions that inflation introduces into the value of assets and income that make up the tax base. From the monetary authority’s point of view, one of the most relevant benefits of low inflation is the credibility that economic agents acquire in inflation targeting, which turns it into an effective nominal anchor on price levels. Upon receiving its mandate, and using its autonomy, Banco de la República began to announce specific annual inflation targets as of 1992. Although the proposed inflation targets were not met precisely during this first stage, a downward trend in inflation was achieved that took it from 32.4% in 1990 to 16.7% in 1998. At that time, the exchange rate was kept within a band. This limited the effectiveness of monetary policy, which simultaneously sought to meet an inflation target and an exchange rate target. The Asian crisis spread to emerging economies and significantly affected the Colombian economy. The exchange rate came under strong pressure to depreciate as access to foreign financing was cut off under conditions of a high foreign imbalance. This, together with the lack of exchange rate flexibility, prevented a countercyclical monetary policy and led to a 4.2% contraction in GDP that year. In this context of economic slowdown, annual inflation fell to 9.2% at the end of 1999, thus falling below the 15% target set for that year. This episode fully revealed how costly it could be, in terms of economic activity, to have inflation and exchange rate targets simultaneously. Towards the end of 1999, Banco de la República announced the adoption of a new monetary policy regime called the Inflation Targeting Plan. This regime, known internationally as ‘Inflation Targeting,’ has been gaining increasing acceptance in developed countries, having been adopted in 1991 by New Zealand, Canada, and England, among others, and has achieved significant advances in the management of inflation without incurring costs in terms of economic activity. In Latin America, Brazil and Chile also adopted it in 1999. In the case of Colombia, the last remaining requirement to be fulfilled in order to adopt said policy was exchange rate flexibility. This was realized around September 1999, when the BDBR decided to abandon the exchange-rate bands to allow the exchange rate to be freely determined in the market.Consistent with the constitutional mandate, the fundamental objective of this new policy approach was “the achievement of an inflation target that contributes to maintaining output growth around its potential.”3 This potential capacity was understood as the GDP growth that the economy can obtain if it fully utilizes its productive resources. To meet this objective, monetary policy must of necessity play a countercyclical role in the economy. This is because when economic activity is below its potential and there are idle resources, the monetary authority can reduce the interest rate in the absence of inflationary pressure to stimulate the economy and, when output exceeds its potential capacity, raise it. This policy principle, which is immersed in the models for guiding the monetary policy stance, makes the following two objectives fully compatible in the medium term: meeting the inflation target and achieving a level of economic activity that is consistent with its productive capacity. To achieve this purpose, the inflation targeting system uses the money market interest rate (at which the central bank supplies primary liquidity to commercial banks) as the primary policy instrument. This replaced the quantity of money as an intermediate monetary policy target that Banco de la República, like several other central banks, had used for a long time. In the case of Colombia, the objective of the new monetary policy approach implied, in practical terms, that the recovery of the economy after the 1999 contraction should be achieved while complying with the decreasing inflation targets established by the BDBR. The accomplishment of this purpose was remarkable. In the first half of the first decade of the 2000s, economic activity recovered significantly and reached a growth rate of 6.8% in 2006. Meanwhile, inflation gradually declined in line with inflation targets. That was how the inflation rate went from 9.2% in 1999 to 4.5% in 2006, thus meeting the inflation target established for that year while GDP reached its potential level. After this balance was achieved in 2006, inflation rebounded to 5.7% in 2007, above the 4.0% target for that year due to the fact that the 7.5% GDP growth exceeded the potential capacity of the economy.4 After proving the effectiveness of the inflation targeting system in its first years of operation, this policy regime continued to consolidate as the BDBR and the technical staff gained experience in its management and state-of-the-art economic models were incorporated to diagnose the present and future state of the economy and to assess the persistence of inflation deviations and expectations with respect to the inflation target. Beginning in 2010, the BDBR established the long-term 3.0% annual inflation target, which remains in effect today. Lower inflation has contributed to making the macroeconomic environment more stable, and this has favored sustained economic growth, financial stability, capital market development, and the functioning of payment systems. As a result, reductions in the inflationary risk premia and lower TES and credit interest rates were achieved. At the same time, the duration of public domestic debt increased significantly going from 2.27 years in December 2002 to 5.86 years in December 2022, and financial deepening, measured as the level of the portfolio as a percentage of GDP, went from around 20% in the mid-1990s to values above 45% in recent years in a healthy context for credit institutions.Having been granted autonomy by the Constitution to fulfill the mandate of preserving the purchasing power of the currency, the tangible achievements made by Banco de la República in managing inflation together with the significant benefits derived from the process of bringing inflation to its long-term target, make the BDBR’s current challenge to return inflation to the 3.0% target even more demanding and pressing. As is well known, starting in 2021, and especially in 2022, inflation in Colombia once again became a serious economic problem with high welfare costs. The inflationary phenomenon has not been exclusive to Colombia and many other developed and emerging countries have seen their inflation rates move away from the targets proposed by their central banks.5 The reasons for this phenomenon have been analyzed in recent Reports to Congress, and this new edition delves deeper into the subject with updated information. The solid institutional and technical base that supports the inflation targeting approach under which the monetary policy strategy operates gives the BDBR the necessary elements to face this difficult challenge with confidence. In this regard, the BDBR reiterated its commitment to the 3.0% inflation target in its November 25 communiqué and expects it to be reached by the end of 2024.6 Monetary policy will continue to focus on meeting this objective while ensuring the sustainability of economic activity, as mandated by the Constitution. Analyst surveys done in March showed a significant increase (from 32.3% in January to 48.5% in March) in the percentage of responses placing inflation expectations two years or more ahead in a range between 3.0% and 4.0%. This is a clear indication of the recovery of credibility in the medium-term inflation target and is consistent with the BDBR’s announcement made in November 2022. The moderation of the upward trend in inflation seen in January, and especially in February, will help to reinforce this revision of inflation expectations and will help to meet the proposed targets. After reaching 5.6% at the end of 2021, inflation maintained an upward trend throughout 2022 due to inflationary pressures from both external sources, associated with the aftermath of the pandemic and the consequences of the war in Ukraine, and domestic sources, resulting from: strengthening of local demand; price indexation processes stimulated by the increase in inflation expectations; the impact on food production caused by the mid-2021 strike; and the pass-through of depreciation to prices. The 10% increase in the minimum wage in 2021 and the 16% increase in 2022, both of which exceeded the actual inflation and the increase in productivity, accentuated the indexation processes by establishing a high nominal adjustment benchmark. Thus, total inflation went to 13.1% by the end of 2022. The annual change in food prices, which went from 17.2% to 27.8% between those two years, was the most influential factor in the surge in the Consumer Price Index (CPI). Another segment that contributed significantly to price increases was regulated products, which saw the annual change go from 7.1% in December 2021 to 11.8% by the end of 2022. The measure of core inflation excluding food and regulated items, in turn, went from 2.5% to 9.5% between the end of 2021 and the end of 2022. The substantial increase in core inflation shows that inflationary pressure has spread to most of the items in the household basket, which is characteristic of inflationary processes with generalized price indexation as is the case in Colombia. Monetary policy began to react early to this inflationary pressure. Thus, starting with its September 2021 session, the BDBR began a progressive change in the monetary policy stance moving away from the historical low of a 1.75% policy rate that had intended to stimulate the recovery of the economy. This adjustment process continued without interruption throughout 2022 and into the beginning of 2023 when the monetary policy rate reached 12.75% last January, thus accumulating an increase of 11 percentage points (pp). The public and the markets have been surprised that inflation continued to rise despite significant interest rate increases. However, as the BDBR has explained in its various communiqués, monetary policy works with a lag. Just as in 2022 economic activity recovered to a level above the pre-pandemic level, driven, along with other factors, by the monetary stimulus granted during the pandemic period and subsequent months, so too the effects of the current restrictive monetary policy will gradually take effect. This will allow us to expect the inflation rate to converge to 3.0% by the end of 2024 as is the BDBR’s purpose.Inflation results for January and February of this year showed declining marginal increases (13 bp and 3 bp respectively) compared to the change seen in December (59 bp). This suggests that a turning point in the inflation trend is approaching. In other Latin American countries such as Chile, Brazil, Perú, and Mexico, inflation has peaked and has begun to decline slowly, albeit with some ups and downs. It is to be expected that a similar process will take place in Colombia in the coming months. The expected decline in inflation in 2023 will be due, along with other factors, to lower cost pressure from abroad as a result of the gradual normalization of supply chains, the overcoming of supply shocks caused by the weather, and road blockades in previous years. This will be reflected in lower adjustments in food prices, as has already been seen in the first two months of the year and, of course, the lagged effect of monetary policy. The process of inflation convergence to the target will be gradual and will extend beyond 2023. This process will be facilitated if devaluation pressure is reversed. To this end, it is essential to continue consolidating fiscal sustainability and avoid messages on different public policy fronts that generate uncertainty and distrust. 1 This Report to Congress includes Box 1, which summarizes the trajectory of Banco de la República over the past 100 years. In addition, under the Bank’s auspices, several books that delve into various aspects of the history of this institution have been published in recent years. See, for example: Historia del Banco de la República 1923-2015; Tres banqueros centrales; Junta Directiva del Banco de la República: grandes episodios en 30 años de historia; Banco de la República: 90 años de la banca central en Colombia. 2 This is why lower inflation has been reflected in a reduction of income inequality as measured by the Gini coefficient that went from 58.7 in 1998 to 51.3 in the year prior to the pandemic. 3 See Gómez Javier, Uribe José Darío, Vargas Hernando (2002). “The Implementation of Inflation Targeting in Colombia”. Borradores de Economía, No. 202, March, available at: https://repositorio.banrep.gov.co/handle/20.500.12134/5220 4 See López-Enciso Enrique A.; Vargas-Herrera Hernando and Rodríguez-Niño Norberto (2016). “The inflation targeting strategy in Colombia. An historical view.” Borradores de Economía, No. 952. https://repositorio.banrep.gov.co/handle/20.500.12134/6263 5 According to the IMF, the percentage change in consumer prices between 2021 and 2022 went from 3.1% to 7.3% for advanced economies, and from 5.9% to 9.9% for emerging market and developing economies. 6 https://www.banrep.gov.co/es/noticias/junta-directiva-banco-republica-reitera-meta-inflacion-3

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