Bibliografie tematiche / Biological levels

Letteratura scientifica selezionata sul tema "Biological levels"

Autore: Grafiati

Pubblicato: 22 giugno 2024

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Articoli di riviste sul tema "Biological levels":

Buxbaum, Robert E. "Biological levels". Nature 373, n. 6515 (febbraio 1995): 567–68. http://dx.doi.org/10.1038/373567a0.

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Love, Bradley C. "Levels of biological plausibility". Philosophical Transactions of the Royal Society B: Biological Sciences 376, n. 1815 (16 novembre 2020): 20190632. http://dx.doi.org/10.1098/rstb.2019.0632.

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Notions of mechanism, emergence, reduction and explanation are all tied to levels of analysis. I cover the relationship between lower and higher levels, suggest a level of mechanism approach for neuroscience in which the components of a mechanism can themselves be further decomposed and argue that scientists' goals are best realized by focusing on pragmatic concerns rather than on metaphysical claims about what is ‘real'. Inexplicably, neuroscientists are enchanted by both reduction and emergence. A fascination with reduction is misplaced given that theory is neither sufficiently developed nor formal to allow it, whereas metaphysical claims of emergence bring physicalism into question. Moreover, neuroscience's existence as a discipline is owed to higher-level concepts that prove useful in practice. Claims of biological plausibility are shown to be incoherent from a level of mechanism view and more generally are vacuous. Instead, the relevant findings to address should be specified so that model selection procedures can adjudicate between competing accounts. Model selection can help reduce theoretical confusions and direct empirical investigations. Although measures themselves, such as behaviour, blood-oxygen-level-dependent (BOLD) and single-unit recordings, are not levels of analysis, like levels, no measure is fundamental and understanding how measures relate can hasten scientific progress. This article is part of the theme issue ‘Key relationships between non-invasive functional neuroimaging and the underlying neuronal activity'.

de Jong, Huib Looren. "Levels of explanation in biological psychology". Philosophical Psychology 15, n. 4 (dicembre 2002): 441–62. http://dx.doi.org/10.1080/0951508021000042003.

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Black, Valerie J., J. D. Graves e D. Reavey. "Climate Change and Levels of Biological Response". Global Ecology and Biogeography Letters 6, n. 2 (marzo 1997): 161. http://dx.doi.org/10.2307/2997579.

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Rezende, Enrico L., e Francisco Bozinovic. "Thermal performance across levels of biological organization". Philosophical Transactions of the Royal Society B: Biological Sciences 374, n. 1778 (17 giugno 2019): 20180549. http://dx.doi.org/10.1098/rstb.2018.0549.

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Thermal performance curves are widely used to describe how ambient temperature impacts different attributes of ectothermic organisms, from protein function to life-history traits, and to predict the potential effects of global warming on ecological systems. Nonetheless, from an analytical standpoint, they remain primarily heuristic and few attempts have been made to develop a formal framework to characterize these curves and disentangle which factors contribute to their variation. Here we employ a nonlinear regression approach to assess if they vary systematically in shape depending on the performance proxy of choice. We compare curves at contrasting levels of organization, namely photosynthetic rates in plants ( n = 43), running speeds in lizards ( n = 51) and intrinsic rates of population increase in insects ( n = 47), and show with discriminant analyses that differences lie in a single dimension accounting for 99.1% of the variation, resulting in 75.8% of classification accuracy. Differences revolve primarily around the thermal range for elevated performance (greater than or equal to 50% of maximum performance), which is broader for photosynthetic rates (median of 26.4°C), intermediate for running speeds (19.5°C) and narrower for intrinsic rates of increase (12.5°C). We contend, confounding taxonomic factors aside, that these differences reflect contrasting levels of biological organization, and hypothesize that the thermal range for elevated performance should decrease at higher organization levels. In this scenario, instantaneous or short-term measures of performance may grossly overestimate the thermal safety margins for population growth and reproduction. Taken together, our analyses suggest that descriptors of the curve are highly correlated and respond in tandem, potentially resulting in systematic variation in shape across organization levels. Future studies should take into consideration this potential bias, address if it constitutes a general pattern and, if so, explain why and how it emerges. This article is part of the theme issue ‘Physiological diversity, biodiversity patterns and global climate change: testing key hypotheses involving temperature and oxygen’.

Perelló, Joan, e Felix Grases. "Phytate levels in biological fluids of mammals". Journal of Chromatography B 960 (giugno 2014): 255–57. http://dx.doi.org/10.1016/j.jchromb.2013.12.016.

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Marchal, P. "Multi-annual TACs and minimum biological levels". ICES Journal of Marine Science 52, n. 5 (ottobre 1995): 797–807. http://dx.doi.org/10.1006/jmsc.1995.0076.

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Vattala, H. D., S. D. Wratten, C. B. Phillips, E. L. Wackers e S. P. Worner. "Measuring parasitoid carbohydrate levels to improve biological control". New Zealand Plant Protection 58 (1 agosto 2005): 135–39. http://dx.doi.org/10.30843/nzpp.2005.58.4286.

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Lifetime carbohydrate levels were compared in the laboratory between unfed and honeyfed Microctonus hyperodae (Hymenoptera Braconidae) a parasitoid of the Argentine stem weevil Listronotus bonariensis (Coleoptera Curculionidae) High performance liquid chromatography (HPLC) was used to analyse sugars in individual parasitoids and showed that fed and unfed parasitoids can be distinguished by measuring the total sugar levels Furthermore the fructose/total sugar ratio (f/T) of honeyfed M hyperodae was always higher than that of the unfed individuals This method should prove very useful for determining the nutritional status of fieldcollected parasitoids and for evaluating the benefits gained by parasitoids through the provision of floral resources in the field

Fareed, J., D. D. Callas, D. Hoppensteadt e E. W. Bermes. "Tissue factor antigen levels in various biological fluids". Blood Coagulation & Fibrinolysis 6, Sup 1 (giugno 1995): S32—S36. http://dx.doi.org/10.1097/00001721-199506001-00006.

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Iverson, Erik N. K., Rachel Nix, Ash Abebe e Justin C. Havird. "Thermal Responses Differ across Levels of Biological Organization". Integrative and Comparative Biology 60, n. 2 (1 giugno 2020): 361–74. http://dx.doi.org/10.1093/icb/icaa052.

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Synopsis Temperature is one of the most important environmental factors driving the genome-to-phenome relationship. Metabolic rates and related biological processes are predicted to increase with temperature due to the biophysical laws of chemical reactions. However, selection can also act on these processes across scales of biological organization, from individual enzymes to whole organisms. Although some studies have examined thermal responses across multiple scales, there is no general consensus on how these responses vary depending on the level of organization, or whether rates actually follow predicted theoretical patterns such as Arrhenius-like exponential responses or thermal performance curves (TPCs) that show peak responses. Here, we performed a meta-analysis on studies of ectotherms where biological rates were measured across the same set of temperatures, but at multiple levels of biological organization: enzyme activities, mitochondrial respiration, and/or whole-animal metabolic rates. Our final dataset consisted of 235 pairwise comparisons between levels of organization from 13 publications. Thermal responses differed drastically across levels of biological organization, sometimes showing completely opposite patterns. We developed a new effect size metric, “organizational disagreement” (OD) to quantify the difference in responses among levels of biological organization. Overall, rates at higher levels of biological organization (e.g., whole animal metabolic rates) increased more quickly with temperature than rates at lower levels, contrary to our predictions. Responses may differ across levels due to differing consequences of biochemical laws with increasing organization or due to selection for different responses. However, taxa and tissues examined generally did not affect OD. Theoretical TPCs, where rates increase to a peak value and then drop, were only rarely observed (12%), possibly because a broad range of test temperatures was rarely investigated. Exponential increases following Arrhenius predictions were more common (29%). This result suggests a classic assumption about thermal responses in biological rates is rarely observed in empirical datasets, although our results should be interpreted cautiously due to the lack of complete thermal profiles. We advocate for authors to explicitly address OD in their interpretations and to measure thermal responses across a wider, more incremental range of temperatures. These results further emphasize the complexity of connecting the genome to the phenome when environmental plasticity is incorporated: the impact of the environment on the phenotype can depend on the scale of organization considered.

Più fonti

Tesi sul tema "Biological levels":

Clarke, Ellen. "Biological individuality and the levels of selection". Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529868.

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Phan, Thi Thanh Hoi [Verfasser]. "Testing levels of competencies in biological experimentation / Thi Thanh Hoi Phan". Kiel : Universitätsbibliothek Kiel, 2008. http://d-nb.info/1019552891/34.

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Walker, Martin Keith. "Determination pf physiological levels of alkanals and hydroxyalkenals in biological samples". Thesis, Brunel University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385819.

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Sousa, Ana Catarina Almeida. "Levels and biological effects of selected EDC's in the portuguese coast". Doctoral thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/980.

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Doutoramento em Biologia
Os compostos orgânicos de estanho (OTs), de entre os quais se destaca o tributilestanho (TBT), encontram-se amplamente dispersos no meio aquático devido à sua intensa utilização como agente biocida em tintas antivegetativas. Estudos anteriores sobre a poluição por organoestanhos em Portugal demonstraram que estes compostos se encontram presentes não só na linha de costa mas também em zonas da plataforma, sendo as zonas portuárias (onde se incluem portos comerciais, portos de pesca, marinas e estaleiros navais) os principais focos de poluição. A presente tese tem como objectivo investigar o estado actual da poluição por organoestanhos na costa Portuguesa confirmando se os padrões espaciais acima descritos se mantêm, por meio da quantificação de diversos OTs, nomeadamente, butilestanhos, fenilestanhos e octilestanhos. Assim, os níveis destes compostos foram avaliados em populações de Mytilus galloprovincialis e Nassarius reticulatus ao longo da costa continental Portuguesa, com particular incidência na Ria de Aveiro onde se quantificaram os níveis de OTs em mexilhões, gastrópodes e sedimentos, recolhidos numa malha de amostragem mais densa. A distribuição espacial dos organoestanhos foi determinada utilizando o bivalve M. galloprovincialis como espécie bioindicadora. Os níveis totais de estanho (SnT) foram quantificados nos tecidos do mexilhão e relacionados com os níveis totais de OTs nos mesmos tecidos, incluindo monobutilestanho (MBT), dibutilestanho (DBT), tributilestanho (TBT), difenilestanho (DPhT), trifenilestanho (TPhT), monoctilestanho (MOcT) e dioctilestanho (DOct). A contribuição dos OTs para os valores de estanho total (SnT) foi superior nas estações de amostragem localizadas no interior de portos onde atingiram proporções próximas dos 50%. De entre estes, os butilestanhos (BuTs=MBT+DBT+TBT) contribuíram em média com 98.6% para o valor total de OTs, tendo sido detectados em todas as amostras analisadas. Os valores mais elevados foram registados no interior ou na proximidade de portos, corroborando a ideia anterior de que constituem importantes focos de poluição. A variação das concentrações de TBT no mexilhão situou-se entre os 0,9 e 720 ng Sn.g-1 de peso seco (ps). Estes valores são, em 69% das estações amostradas, superiores ao valor do proposto pela OSPAR (4,9 ng TBT-Sn.g-1 ps) para tecidos de mexilhão o que sugere a forte probabilidade de ocorrência de efeitos adversos sobre os ecossistemas. Os níveis de OTs foram também quantificados em tecidos de N. reticulatus recolhidos ao longo da costa em 2008 Os butilestanhos representaram a maioria dos compostos organoestânicos quantificados e os níveis mais elevados foram novamente detectados no interior ou nas imediações de portos. Os valores de TBT nos tecidos deste gastrópode variaram entre 3,5 e 380 ng Sn.g-1 ps, representando uma percentagem média de 50,4% do total de butilestanhos. Simultaneamente, os níveis de imposex foram também avaliados e relacionados com os valores deste composto nos tecidos. As distribuições espaciais de imposex e de TBT seguiram a mesma tendência, sendo que em todos os locais amostrados foram encontradas fêmeas afectadas. Os valores de VDSI (índice da sequência do vaso deferente) variaram entre 0,2 e 4,4. Em 91% dos locais os valores de VDSI foram superiores a 0,3 (definido pela OSPAR como o valor de VDSI em N. reticulatus acima do qual o objectivo de qualidade ecológica não é atingido), confirmando a suspeição da existência de efeitos adversos nos ecossistemas. Em todos os compartimentos analisados na Ria de Aveiro, os butilestanhos foram os principais contribuintes para estanho orgânico total. A utilização do imposex em N. reticulatus como biomarcador da poluição por TBT permitiu determinar um gradiente decrescente desde o interior da Ria (onde se situa a zona portuária) até zonas costeiras adjacentes. O mesmo gradiente foi observado relativamente às concentrações de TBT em tecidos de mexilhão. Para os sedimentos, as concentrações de TBT são bastante variáveis com valores entre 2,7 e 1780 ng Sn.g-1 ps encontrando-se significativamente correlacionadas com o conteúdo em matéria orgânica da amostra. Em todas as amostras analisadas os níveis de TBT são elevados e superiores ao valor inferior (provisório) de EAC (critério de avaliação ambiental) proposto pela OSPAR (0,004 ng TBT-Sn.g-1 ps). A análise da evolução temporal da poluição por TBT ao longo da costa foi concretizada por meio da comparação entre níveis de organoestanhos em N. reticulatus em amostras de 2008 e 2003 e também através da comparação dos níveis de imposex registados em campanhas realizadas naqueles dois anos. Os resultados obtidos indicam a ocorrência de reduções significativas nas concentrações de TBT, DBT e MBT, assim como uma diminuição significativa nos valores de VDSI entre 2003 e 2008. Os resultados obtidos sugerem que a redução verificada se deve à implementação do Regulamento 782/2003 da Comunidade Europeia, que tem por objectivo a erradicação das descargas e emissões de TBT para o ambiente a partir dos sistemas antivegetativos A diminuição da poluição por TBT ao longo dos últimos anos foi acompanhada por um aumento no número de fêmeas com um vaso deferente, mas sem pénis (imposex do tipo b): 3,5% em 2000, 11% em 2003 e 24% em 2008. Um aumento no número de locais onde se registou o fenómeno também é evidente: dois em 2000, sete em 2003 e treze em 2008. A proporção de fêmeas b no estádio 1 de VDS apresentou igual tendência com aumento de 38% em 2000 para 65% em 2008. O aumento no número de fêmeas com esta via parece estar associado à diminuição da poluição por TBT. Face à esperada diminuição da presença do composto no meio ambiente, devido à sua proibição, o aumento de fêmeas com imposex do tipo b é previsível. A ocorrência de compostos xenoestrogénicos no ambiente aquático foi também estudada e os níveis de estrona (E1), 17α-e 17β-estradiol (E2), 17α- etinilestradiol (EE2), bisfenol-A (BPA) e nonilfenol (NP) foram quantificados em efluentes de estações de tratamento de águas residuais (ETARs) localizadas na região de Aveiro, bem como no efluente final descarregado no Oceano Atlântico, através de um emissário submarino (S. Jacinto), sendo amostras recolhidas na entrada da Ria e ao largo usadas como referência. Os níveis de hormonas esteróides e compostos fenólicos registados nos locais de referência são baixos. De entre as hormonas esteróides os níveis mais elevados foram registados para a estrona, com valores máximos de 85.3 ng.L- 1 . Os níveis mais elevados de compostos fenólicos foram detectados em efluentes industriais (máximos de NP e BPA de 2410 ng.L-1 e 897 ng.L-1 , respectivamente). Os resultados obtidos sugerem que os níveis de compostos xenoestrogénicos em locais de referência são baixos e não parecerem acarretar risco ecológico, no entanto o mesmo não será verdadeiro para as imediações do emissário de S. Jacinto que liberta efluentes com concentrações muito elevadas de E1, NP e BPA. Foram realizadas experiências laboratoriais de forma a elucidar o papel do receptor retinóico X (RXR) no mecanismo de indução de imposex (presentemente o mecanismo que demonstra maior promessa na explicação do desencadear deste fenómeno). Fêmeas de Nucella lapillus e N. reticulatus foram injectadas com TBT em etanol ou com ácido 9-cis- retinóico em FBS (soro fetal bovino) tendo-se procedido à sua observação nos 30 dias subsequentes. Tanto o TBT como o 9CRA induziram o desenvolvimento de imposex em N. lapillus e N. reticulatus. Aumentos significativos nos valores de VDSI e FPL entre o controlo de etanol e o tratamento de TBT e o controlo de FBS e o tratamento de 9CRA foram registados. Os resultados obtidos fornecem novas provas do envolvimento da via de sinalização associada ao RXR no desenvolvimento de imposex em ambas as espécies.

Lee, Nina Louise. "The roles of diet and SirT3 levels in mediating signaling network changes in insulin resistance". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81674.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Biological Engineering, 2013.
Title as it appears in MIT Commencement Exercises program, June 2013: Signaling network changes in high fat diet-induced insulin resistance Cataloged from PDF version of thesis.
Includes bibliographical references (p. 73-80).
The goal of my research is to understand the mechanism by which high fat diets mediate insulin sensitivity and the role SirT3 plays in high fat diet-induced insulin resistance. Insulin resistance is defined as the inability of cells and tissues to respond properly to ordinary amounts of insulin and is a precursor to many metabolic diseases such as diabetes and cardiovascular disease. Obesity, brought on in large part by caloric excess from high fat diet feeding, is a major contributor to insulin resistance. The recent drastic increase in the prevalence of obesity makes it imperative that steps are taken to more effectively treat and cure obesity-linked diseases such as diabetes. To identify optimal therapeutic targets, it is crucial to first gain a mechanistic understanding of obesity-induced insulin resistance, and understand how specific changes in the signaling network affect insulin sensitivity. Previous work has demonstrated that levels of SirT3, a mitochondrial protein deacetylase, are diet dependent. Additionally, SirT3 expression levels have been shown to mediate insulin and glucose tolerance in animals in a diet-dependent manner. Perturbations in SirT3 levels also alter the levels of phosphorylation on several canonical insulin signaling proteins. In my research, I further investigated the link between SirT3, diet and insulin resistance from a signaling network perspective. Using mouse liver as a model system, I analyzed liver tissue from mice fed a normal diet (insulin sensitive) or mice fed a high fat diet, thus inducing insulin resistance. Quantification of phenotypic and network events in response to insulin and utilization of computational techniques revealed activated pathways and nodes mediating insulin response, some of which had not been previously associated with the canonical insulin signaling network. I extended the study to analyze the role SirT3 plays in diet-mediated insulin sensitivity by perturbing the level of SirT3 in mice on both normal chow and high fat diets. The results of this research are useful for designing more efficacious therapies to treat insulin resistance-induced diseases.
by Nina Louise Lee.
S.M.

JOHNSON, GREGORY S. "ON THE RELATIONSHIP BETWEEN PSYCHOLOGY AND NEUROBIOLOGY: LEVELS IN THE COGNITIVE AND BIOLOGICAL SCIENCES". University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1178290821.

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Gonzales, Melissa 1963. "Occupational exposure to azinphos-methyl: Correlating biological markers to environmental residue levels". Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/291604.

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Peach harvester exposure to azinphos-methyl (AZM) residues estimated by the Transfer Factor (TF) ratio of Dislodgeable Foliar Residue (DFR) to Daily Dermal Exposure (DDE) was compared to estimates based on the relationship between dermal exposure and dialkylphosphate metabolite excretion. DFR was monitored in four orchards from the time of pesticide application through harvest. Eleven male harvesters wore cotton tee-shirt dosimeters and provided area-specific skin washes and wipes for DDE monitoring during work operations. Urinary dialkylphosphate metabolites of AZM were also monitored and compared to DDE results. During a later harvest for which DDE was not determined, the dermal exposure estimated by the TF (1,310 μg) was comparable to the estimates based on dialkylphosphate excretion (1,456-1,534 μg). A repeated measures ANOVA showed that harvesters' cholinesterase levels were significantly lower than 'non-harvesters'. No significant reductions in cholinesterase levels were detected over time.

Hodges, Jennefer Anne. "Making sense of biological naturalism". Thesis, University of Hertfordshire, 2014. http://hdl.handle.net/2299/13889.

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Searle’s theory of Biological Naturalism has been largely ignored in the philosophical literature and Searle’s commentators are confused by his seemingly contradictory views. In this dissertation I attempt to make sense of Biological Naturalism. In chapter 2 I will ascertain which concerns prevent Searle’s readers from understanding his position. The remaining chapters aim to dissolve the tensions and dispel any confusion. Chapter 3 considers Searle’s notion of first-person ontology, finding that it expresses a belief that experiences are essentially subjective and qualitative. In chapter 4 I consider the notions of levels of description, causal reduction and what Searle means by causation and realisation. Chapter 5 turns to the question of how to categorise Searle’s position. Many of his critics charge him with being a property dualist. By highlighting the difference between the meaning of irreducibility intended by the property dualist and Searle I show that there is sufficient difference in their use of the term so as to reject an interpretation of Biological Naturalism as a form of property dualism. Chapter 6 is where I turn to the other end of the physicalism/dualism spectrum and assess whether Searle should be seen as holding a form of identity theory. I first argue for a neutral form of identity that I call real identity, which does not include the inherent reductive privileging of standard identity. I then argue that Searle should be seen as advocating a form of real identity theory; a form of token identity theory which does not privilege the physical over the mental. In chapter 7 I return to the main barriers to making sense of Biological Naturalism which I identified in chapter 2 and lay out my response to each. I conclude with a coherent interpretation of Searle’s position.

Brooks, Daniel Stephen [Verfasser]. "The concept of levels of organization in the biological sciences / Daniel Stephen Brooks". Bielefeld : Universitätsbibliothek Bielefeld, 2016. http://d-nb.info/1082033960/34.

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Canty, Martin Neil. "Marine pollution and echinoderms : a biomarker study integrating different levels of biological organisation". Thesis, University of Plymouth, 2009. http://hdl.handle.net/10026.1/1310.

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There is growing concern that the invertebrate test organisms commonly employed in the field of aquatic ecotoxicology may not be sufficient to accurately screen for the possible deleterious effects of contaminants discharged into the marine environment. The use of echinoderms has been proposed to redress this problem, due to their ecological importance and their evolutionary closeness to the chordates. But to date, there is a paucity of data in the published literature which has utilised the adult stages of echinoderms in laboratory based toxicology studies. The present studies aimed to fill this lack of information. A suite of biomarkers which operated at different levels of biological organisation (sub-cellular, cellular and individual level) were identified for use with different echinoderm species (the common sea star, Asterias rubens, the purple sea urchin, Paracentrotus lividus and the common brittle star, Ophiothrix fragilis). These biomarkers used were micronucleus induction, the Comet assay, the modified Comet assay, phagocytosis, neutral red retention, clearance rate and righting time. Concurrent exposures showed that echinoderms were more sensitive to model contaminants than a commonly used sentinel ecotoxicological test species, namely the blue mussel, Mytilus edulis. These contaminants included: the reference toxicants hydrogen peroxide (Chapter 2) and methyl methanesul phonate (Chapter 3); a pharmaceutical, cyclophosphamide (Chapter 3); a polycyclic aromatic hydrocarbon, benzo(a)pyrene (Chapter 4) and a heavy metal, cadmium (Chapter 5). The results for all the exposures showed that the biomarkers which operated at the lower levels of biological organisation (i. e. at the subcellular level – namely the micronucleus and Comet assays) were the most sensitive at detecting the deleterious effects of the contaminants. But, interestingly, some strong correlations were found between these sub-cellular consequences and those that operated at higher levels of biological organisation (for example, between righting time and both micronucleus induction and Comet assay in Asterias rubens following cyclophosphamide exposure). Theses correlations suggest that biomarkers which operate at the whole organism level (namely righting time and clearance rate) may serve as rapid and accurate indicators of possible damage induced by xenobiotics in echinoderms and bivalve molluscs.

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Libri sul tema "Biological levels":

Zhirmunskiĭ, Alekseĭ Viktorovich. Critical levels in the development of natural systems. Berlin: Springer-Verlag, 1988.

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A, Vernon Philip, a cura di. Biological approaches to the study of human intelligence. Norwood, NJ: Ablex Pub., 1993.

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Bertolaso, Marta. How science works: Choosing levels of explanation in biological sciences. Roma: Aracne editrice S.r.l., 2013.

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Walker, Martin Keith. Determination of physiological levels of alkanals and hydroxyalkenals in biological samples. Uxbridge: Brunel University, 1994.

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Weitkamp, Donald E. Reservoir drawdown biological issues: A discussion paper. Bellevue, Wash: Parametrix, 1992.

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Hunter, Mark A. Hydropower flow fluctuations and salmonids: A review of the biological effects, mechanical causes, and options for mitigation. Olympia, Wash: State of Washington, Dept. of Fisheries, Habitat Management Division, 1992.

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United States. Army. Corps of Engineers. Walla Walla District., a cura di. Lower Snake River biological drawdown test, draft environmental impact statement: Factsheet. Walla Walla, WA: Dept. of the Army, Walla Walla District, Corps of Engineers, 1994.

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Hill, Jeffrey E. Biological synopsis of five selected Florida Centrarchid fishes with an emphasis on the effects of water level fluctuations. Palatka, Fl]: St. Johns River Water Management District, 2005.

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Weitkamp, Donald E. Biological risks associated with a John Day Reservoir drawdown. Seattle, Wash: Parametrix, 1993.

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Douglas, Grahn, Carnes Bruce A, Thomson John F, U.S. Nuclear Regulatory Commission. Office of Nuclear Regulatory Research. Division of Regulatory Applications., Argonne National Laboratory. Division of Biological and Medical Research. e Argonne National Laboratory, a cura di. Relative biological effectiveness (RBE) of fission neutrons and gamma rays at occupational exposure levels. Washington, DC: Division of Regulatory Applications, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, 1987.

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Capitoli di libri sul tema "Biological levels":

Roberts, E. A. "A 3 × 3 factorial with quantitative levels". In Sequential Data in Biological Experiments, 83–105. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-3120-9_3.

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Pawley, James B. "Points, Pixels, and Gray Levels: Digitizing Image Data". In Handbook Of Biological Confocal Microscopy, 59–79. Boston, MA: Springer US, 2006. http://dx.doi.org/10.1007/978-0-387-45524-2_4.

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Hollister, Leo E. "Plasma Levels and the Management of Chronic, Refractory Schizophrenia". In Biological Psychiatry, Higher Nervous Activity, 493–97. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4684-8329-1_72.

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Ramaswamy, Babu Rajendran. "Analytical Techniques for Trace Levels of Organotin Compounds in the Marine Environment". In Biological Effects by Organotins, 3–25. Tokyo: Springer Japan, 2016. http://dx.doi.org/10.1007/978-4-431-56451-5_1.

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Yesavage, Jerome A. "Plasma Levels as Predictors of Clinical Response and Violent Behavior". In Biological Psychiatry, Higher Nervous Activity, 499–508. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4684-8329-1_73.

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Putten, Theodore Van. "Guidelines to use of Plasma Levels From a Clinical Perspective". In Biological Psychiatry, Higher Nervous Activity, 509–14. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4684-8329-1_74.

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Araus, J. L., L. Tapia, J. Azcon-Bieto e A. Caballero. "Photosynthesis, Nitrogen Levels, and Dry Matter Accumulation in Flag Wheat Leaves During Grain Filling". In Biological Control of Photosynthesis, 199–207. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4384-1_18.

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Horak, J., B. Enderle, H. Bakirci e G. A. Urban. "Amperometric Monitoring of Substance-P Levels in Biological Fluids". In IFMBE Proceedings, 384. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-03887-7_111.

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West, Sean, e Hesham Ali. "Sensitivity Analysis of Granularity Levels in Complex Biological Networks". In Biomedical Engineering Systems and Technologies, 167–88. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-54717-6_10.

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Sepriani, Rika, D. Deswandi, Hilmainur Syampurma, Siska Alicia Farma e Abdul Razak. "Vitamin C Levels and Ph Values in Various Types of Ginger Infused Water". In Advances in Biological Sciences Research, 275–81. Dordrecht: Atlantis Press International BV, 2023. http://dx.doi.org/10.2991/978-94-6463-166-1_36.

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Atti di convegni sul tema "Biological levels":

Kitney, R. I., e C. L. Poh. "Geometric Framework linking different levels of the Biological Continuum". In 2005 IEEE Engineering in Medicine and Biology 27th Annual Conference. IEEE, 2005. http://dx.doi.org/10.1109/iembs.2005.1615356.

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"Serum Creatinine and Uric Acid Levels in Current Adult Male Smokers Versus Nonsmokers". In 4TH INTERNATIONAL CONFERENCE ON BIOLOGICAL & HEALTH SCIENCES. Cihan University - Erbil, 2022. http://dx.doi.org/10.24086/biohs2022/paper.600.

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"Interlukin-6 levels in relation to COVID-19 vaccine". In 4th International Conference on Biological & Health Sciences (CIC-BIOHS’2022). Cihan University, 2022. http://dx.doi.org/10.24086/biohs2022/paper.735.

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SARS COV-2 is a pulmonary disease known as COVID -19 that has been infecting people since late December 2019 and continues to cause organ failure due to elevated cytokines and chemokines causing cytokine storm syndrome, elevating levels of Interleukin-6 and lactate dehydrogenase enzyme (LDH). In this study, a total of 120 cases were included that were collected in Cihan University-Erbil Campus from October to November 2021. In these 120 samples, categorized into four different groups (NN, CN, NV and CV) N is for non-vaccinated, C is for COVID-19 and V is for vaccinated, each group consisting of 30 cases. The study found that those who had COVID-19 infection and were vaccinated had much greater levels of interleukin 6 than the other groups. COVID-19 causes IL-6 to rise, but immunization doubles the level. Furthermore, the serum samples taken from them for lactate-dehydrogenase LDH test, the study showed that both COVID-19 infection and vaccination will cause a massive increase in LDH level in the body. Lastly, there were hematological parameters for the samples which indicated that those who got COVID-19 infection their WBC and monocyte were increased compared to those who got vaccinated which was significantly increased. The study did a platelet test for the samples, but there was no significant difference between the groups.

"Interferon Gamma Levels in Relation to COVID-19 Vaccine". In 4th International Conference on Biological & Health Sciences (CIC-BIOHS’2022). Cihan University, 2022. http://dx.doi.org/10.24086/biohs2022/paper.691.

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One-hundred and twenty cases studied in this study for whom they take vaccine dose or not, for infected and non-infected with coronavirus. They are classified to four groups (Covid-19 – Non-Vaccinated = CN); (Covid-19 – Vaccinated = CV); (Non Covid-19 – Non-Vaccinated = NN); (Non-Covid-19 – Vaccinated = NV) each group involved 30 cases. After withdrawing the blood from each person, the blood poured into two tube (5 ml to Gel tube and 2 ml to EDTA tube) and immunological parameters directly performed by hematological analyzer, while the serum, after centrifugation of blood and storing them in special tubes, used to estimation of IFN- γ by Enzyme Linked Immunosorbent Assay (ELIZA) and Lactate Dehydrogenase (LDH) by chemical analyzer. The study showed that there is a slight increasing in IFN- γ as pro-inflammatory cytokine and LDH concentration which related to the severity of the disease, while there is rising in WBC number both vaccinated groups and cases with COVID-19 infection.

"Interleukin-10 levels in relation to COVID-19 vaccine". In 4th International Conference on Biological & Health Sciences (CIC-BIOHS’2022). Cihan University, 2022. http://dx.doi.org/10.24086/biohs2022/paper.714.

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The study was conducted in Cihan University-Erbil campus in November 2021. All subjects were asked questions regarding their history, using a questionnaire sheet. Blood was investigated for the Interleukin-10 level, Lactate Dehydrogenase (LDH) and hematological parameters. The mean serum level of IL-10 was significantly higher in Covid-19, non-vaccinated than Covid-19, vaccinated individuals. Moreover, the level was also equally significant and higher in non-Covid-19, vaccinated than non-Covid-19, non-vaccinated. Non-significant differences were found between Covid-19, vaccinated and non-Covid-19, non-vaccinated individuals. And between Covid-19, non-vaccinated and non-Covid-19, vaccinated individuals. The mean serum levels of LDH were found to be significantly lower in non-Covid-19, non-vaccinated, indicating a significant rise of LDH in all other groups. Despite the rise in all three groups a significant difference was not found between them. The total WBC count shows a significant increase in both non-vaccinated groups. While the mean level of lymphocytes counts reveals non-significant decrease in non-Covid-19, vaccinated group in comparison to the other groups. However, the mean monocyte counts of Covid-19, vaccinated group revealed a significant rise in comparison to other groups. In addition, the mean counts of granulocyte showed a significant increase in both non-vaccinated groups in comparison with vaccinated groups. Platelet mean count presented a non-significant difference when comparing all groups. Our current study may indicate the potency of the vaccines.

"The Vegetative Growth and Development of Dracocephalum Moldavica under Different Soil Moisture Levels". In International Conference on Civil, Biological and Environmental Engineering. International Institute of Chemical, Biological & Environmental Engineering, 2014. http://dx.doi.org/10.15242/iicbe.c514595.

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Matula, Thomas L., e Kevin Greene. "Affordable Design for Space-Based Biological Laboratories for Alternative Gravity Levels". In 16th Biennial International Conference on Engineering, Science, Construction, and Operations in Challenging Environments. Reston, VA: American Society of Civil Engineers, 2018. http://dx.doi.org/10.1061/9780784481899.025.

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Kovacs, Melinda H., Zaharie Moldovan e Dumitru Ristoiu. "Mutagenic contaminants bioaccumulation detection at ultratrace levels from complex biological matrices". In Advanced Topics in Optoelectronics, Microelectronics, and Nanotechnologies 2012, a cura di Paul Schiopu e Razvan Tamas. SPIE, 2012. http://dx.doi.org/10.1117/12.966599.

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Guzelian, Andrew A., James M. Sylvia, James A. Janni, Susan L. Clauson e Kevin M. Spencer. "SERS of whole-cell bacteria and trace levels of biological molecules". In Environmental and Industrial Sensing, a cura di Steven D. Christesen e Arthur J. Sedlacek III. SPIE, 2002. http://dx.doi.org/10.1117/12.455736.

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"The Effects of Low Frequency Ultrasound on Serum Levels of Testosterone in Male Rats". In 2016 International Conference on Biological and Environmental Science. Universal Researchers, 2016. http://dx.doi.org/10.17758/ur.u0616233.

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Rapporti di organizzazioni sul tema "Biological levels":

Grahn, D., J. Thomson e B. Carnes. Relative biological effectiveness (RBE) of fission neutrons and gamma rays at occupational exposure levels. Office of Scientific and Technical Information (OSTI), gennaio 1990. http://dx.doi.org/10.2172/5017081.

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Samish, Michael, K. M. Kocan e Itamar Glazer. Entomopathogenic Nematodes as Biological Control Agents of Ticks. United States Department of Agriculture, settembre 1992. http://dx.doi.org/10.32747/1992.7568104.bard.

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This research project was aimed to create a basis for the use of entomopathogenic nematodes (Steinernematidae an Heterorhabditidae) for biological control of ticks. The specific objectives were to determinate: 1) Nematode virulence to various. 2) Host-parasite interactions of nametodes and ticks. 3) Effect of environmental factors of tick habitats on nematode activity. 4) To test nematodes (anti tick activity) in defined field trials. Throughout the project 12 nematode strains from five species were tested in laboratory assays against all developmental stages of eight tick species. All tick species were found susceptible to nematode infection. The nematode strains the IS-5 and IS-12 of Heterorhabditis bacteriophora were found to be the most virulent. Engorged adults, particularly females, were the most susceptible stages. Despite the high susceptibility, ticks are not suitable hosts for nematode development and propagation. Entomopathogenic namatodes enter ticks and kill them by releasing the symbiotic bacteria from their foregut. Under favorable conditions, i.e. moist soil, moderate temperature (22-27oC) and sandy soil, nematode efficacy against B. annulatus engorged females was very high (>5% w/w) and high animal manure concentration in soil adversely effect nematode efficacy. In field trails, nematodes were effective when soil moisture was maintained at high levels. The results indicate that under favorable conditions the nematodes show promise as a biological control method for ticks. However, we still face several potential obstacles to the use of nematodes under less favorable conditions.

Audsley, Neil, Gonzalo Avila, Claudio Ioratti, Valerie Caron, Chiara Ferracini, Tibor Bukovinszki, Marc Kenis et al. Brown marmorated stink bug, Halyomorpha halys (StÃ¥l). Euphresco, 2023. http://dx.doi.org/10.1079/20240228464.

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The brown marmorated stink bug, Halyomorpha halys, a severe pest of Asian origin, has spread to Europe, North America and South America, causing significant damage to fruits, vegetables and nuts. Chemical control methods are often ineffective due to the high mobility, broad host range and resilience of the pest. Biological control, particularly using egg parasitoids, presents a promising long-term solution. The egg parasitoid Trissolcus japonicus is considered the most promising candidate for biological control, with adventive populations found in Europe and North America showing varying levels of impact on H. halys populations. Another egg parasitoid, Trissolcus mitsukurii, has also been detected in Europe and shows potential as a biological control agent. While these parasitoids are oligophagous and occasionally target non-H. halys species, their strong preference for H. halys makes them viable for biological control efforts. Ongoing introduction and redistribution efforts aim to enhance their impact on H. halys populations.

Peplow, Dan, e Robert Edmonds. Effects of Mine Waste Contamination on Fish and Wildlife Habitat at Multiple Levels of Biological Organization in the Methow River, 2001-2002 Annual Report. Office of Scientific and Technical Information (OSTI), giugno 2002. http://dx.doi.org/10.2172/806231.

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Tran, Minh, Devashree Niraula, Chloe Pottinger-Glass, Sizwile Khoza, Ganesh Dhungana e Cynthia Nitsch. A rights-based approach to reduce biological hazards and disaster risk: a case study of Bharatpur, Nepal. Stockholm Environment Institute, marzo 2023. http://dx.doi.org/10.51414/sei2023.019.

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This brief synthesizes findings of a case study of Bharatpur, Nepal, that examined ways to increase the coherence of urban planning, public services, and disaster-risk reduction measures, and, at the same time, integrate the needs of the most vulnerable groups. Based on this assessment, the authors recommend five policy changes. 1) Increase policy coherence and institutional coordination across levels and sectors of government. 2) Pay attention to the different impacts hazards have on different groups; 3) Develop capacity and allocate resources to help local government address risks for different groups. 4) Customize policies to address needs, particularly in peri-urban and rural areas engulfed by rapid urban growth. 5) Use community-engagement approaches to include and address issues raised by residents of marginalized communities.

Ghanim, Murad, Joe Cicero, Judith K. Brown e Henryk Czosnek. Dissection of Whitefly-geminivirus Interactions at the Transcriptomic, Proteomic and Cellular Levels. United States Department of Agriculture, febbraio 2010. http://dx.doi.org/10.32747/2010.7592654.bard.

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Our project focuses on gene expression and proteomics of the whitefly Bemisia tabaci (Gennadius) species complex in relation to the internal anatomy and localization of expressed genes and virions in the whitefly vector, which poses a major constraint to vegetable and fiber production in Israel and the USA. While many biological parameters are known for begomovirus transmission, nothing is known about vector proteins involved in the specific interactions between begomoviruses and their whitefly vectors. Identifying such proteins is expected to lead to the design of novel control methods that interfere with whitefly-mediated begomovirus transmission. The project objectives were to: 1) Perform gene expression analyses using microarrays to study the response of whiteflies (B, Q and A biotypes) to the acquisition of begomoviruses (Tomato yellow leaf curl (TYLCV) and Squash leaf curl (SLCV). 2) Construct a whitefly proteome from whole whiteflies and dissected organs after begomovirus acquisition. 3) Validate gene expression by q-RTPCR and sub-cellular localization of candidate ESTs identified in microarray and proteomic analyses. 4) Verify functionality of candidate ESTs using an RNAi approach, and to link these datasets to overall functional whitefly anatomical studies. During the first and second years biological experiments with TYLCV and SLCV acquisition and transmission were completed to verify the suitable parameters for sample collection for microarray experiments. The parameters were generally found to be similar to previously published results by our groups and others. Samples from whole whiteflies and midguts of the B, A and Q biotypes that acquired TYLCV and SLCV were collected in both the US and Israel and hybridized to B. tabaci microarray. The data we analyzed, candidate genes that respond to both viruses in the three tested biotypes were identified and their expression that included quantitative real-time PCR and co-localization was verified for HSP70 by the Israeli group. In addition, experiments were undertaken to employ in situ hybridization to localize several candidate genes (in progress) using an oligonucleotide probe to the primary endosymbiont as a positive control. A proteome and corresponding transcriptome to enable more effective protein identification of adult whiteflies was constructed by the US group. Further validation of the transmission route of begomoviruses, mainly SLCV and the involvement of the digestive and salivary systems was investigated (Cicero and Brown). Due to time and budget constraints the RNAi-mediated silencing objective to verify gene function was not accomplished as anticipated. HSP70, a strong candidate protein that showed over-expression after TYLCV and SLCV acquisition and retention by B. tabaci, and co-localization with TYLCV in the midgut, was further studies. Besides this protein, our joint research resulted in the identification of many intriguing candidate genes and proteins that will be followed up by additional experiments during our future research. To identify these proteins it was necessary to increase the number and breadth of whitefly ESTs substantially and so whitefly cDNAs from various libraries made during the project were sequenced (Sanger, 454). As a result, the proteome annotation (ID) was far more successful than in the initial attempt to identify proteins using Uniprot or translated insect ESTs from public databases. The extent of homology shared by insects in different orders was surprisingly low, underscoring the imperative need for genome and transcriptome sequencing of homopteran insects. Having increased the number of EST from the original usable 5500 generated several years ago to >600,000 (this project+NCBI data mining), we have identified about one fifth of the whitefly proteome using these new resources. Also we have created a database that links all identified whitefly proteins to the PAVEdb-ESTs in the database, resulting in a useful dataset to which additional ESTS will be added. We are optimistic about the prospect of linking the proteome ID results to the transcriptome database to enable our own and other labs the opportunity to functionally annotate not only genes and proteins involved in our area of interest (whitefly mediated transmission) but for the plethora of other functionalities that will emerge from mining and functionally annotating other key genes and gene families in whitefly metabolism, development, among others. This joint grant has resulted in the identification of numerous candidate proteins involved in begomovirus transmission by B. tabaci. A next major step will be to capitalize on validated genes/proteins to develop approaches to interfere with the virus transmission.

LAZAREV, V. I., R. I. LAZAREVА, B. S. ILJIN e T. V. GAVRILOVA. THE EFFICIENCY OF TECHNOLOGIES OF CULTIVATION OF SPRING WHEAT WITH DIFFERENT LEVELS OF BIOLOGICAL AND RESOURCE SAVING IN THE CON- DITIONS OF THE KURSK REGION. Ljournal, 2019. http://dx.doi.org/10.18411/issn1997-0749.2019-07-07.

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Kloepper, Joseph W., e Ilan Chet. Endophytic Bacteria of Cotton and Sweet Corn for Providing Growth Promotion and Biological Disease Control. United States Department of Agriculture, gennaio 1996. http://dx.doi.org/10.32747/1996.7613039.bard.

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Endophytes were isolated from 16.7% of surface-disinfested seeds and 100% of stems and roots of field-growth plants. Strains from Israel with broad-spectrum in vitro antibiosis were mainly Bacillus spp., and some were chitinolytic. Following dipping of cut cotton roots into suspensions of these strains, endophytes were detected up to 72 days later by isolation and by autoradiograms of 14C-labelled bacteria. Selected endophytes exhibited biological control potential based on significant reductions in disease severity on cotton inoculated with Rhizoctonia solani or Fusarium oxysporum f. sp. vasinfectum as well as control of Sclerotium rolfsii on bean. Neither salicylic acid nor chitinase levels increased in plants as a result of endophytic colonization, suggesting that the observed biocontrol was not accounted for by PR protein production. Some biocontrol endophytes secreted chitinolytic enzymes. Model endophytic strains inoculated into cotton stems via stem injection showed only limited movement within the stem. When introduced into stems at low concentrations, endophytes increased in population density at the injection site. After examining several experimental and semi-practical inoculation systems, seed treatment was selected as an efficient way to reintroduce most endophytes into plants.

Mooney, Benjamin. Understanding the Efficiency of Energy Flow Through Aquatic Food Webs. Department of Aquatic Resources, Swedish University of Agricultural Sciences, 2024. http://dx.doi.org/10.54612/a.2kg9dkp0ch.

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The efficiency of energy flow through aquatic food webs is crucial for ecosystem functioning. The energy available to higher trophic levels varies across ecosystems and is influenced by factors such as nutrient availability and species composition. Recent research indicates that temperature also plays a significant role in determining energy transfer efficiency. This essay addresses the factors contributing to variability in energy flow efficiency between aquatic ecosystems, with a focus on the impacts of global climate change. It explores how food web characteristics influence energy transfer between trophic levels and examines the challenges in understanding and estimating energy flow due to complex trophic relationships, spatial subsidies, and processes across multiple biological levels. The essay highlights the dynamic response of energy flow efficiency to climate changerelated environmental changes, such as rising temperatures, altered precipitation patterns, and nutrient inputs. Additionally, it identifies gaps in our current understanding and suggests important avenues for further research to improve predictions of energy flow changes, essential for informing sustainable management strategies in the face of environmental change.

Zhou, Ting, Roni Shapira, Peter Pauls, Nachman Paster e Mark Pines. Biological Detoxification of the Mycotoxin Deoxynivalenol (DON) to Improve Safety of Animal Feed and Food. United States Department of Agriculture, luglio 2010. http://dx.doi.org/10.32747/2010.7613885.bard.

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The trichothecene deoxynivalenol (DON, vomitoxin), one of the most common mycotoxin contaminants of grains, is produced by members of the Fusarium genus. DON poses a health risk to consumers and impairs livestock performance because it causes feed refusal, nausea, vomiting, diarrhea, hemolytic effects and cellular injury. The occurrence of trichothecenes contamination is global and they are very resistant to physical or chemical detoxification techniques. Trichothecenes are absorbed in the small intestine into the blood stream. The overall objective of this project was to develop a protecting system using probiotic bacteria that will express trichothecene 3-O-acetyltransferase (Tri101) that convert T-2 to a less toxic intermediate to reduce ingested levels in-situ. The major obstacle that we had faced during the project is the absence of stable and efficient expression vectors in probiotics. Most of the project period was invested to screen and isolate strong promoter to express high amounts of the detoxify enzyme on one hand and to stabilize the expression vector on the other hand. In order to estimate the detoxification capacity of the isolated promoters we had developed two very sensitive bioassays.The first system was based on Saccharomyces cerevisiae cells expressing the green fluorescent protein (GFP). Human liver cells proliferation was used as the second bioassay system.Using both systems we were able to prove actual detoxification on living cells by probiotic bacteria expressing Tri101. The first step was the isolation of already discovered strong promoters from lactic acid bacteria, cloning them downstream the Tri101 gene and transformed vectors to E. coli, a lactic acid bacteria strain Lactococcuslactis MG1363, and a probiotic strain of Lactobacillus casei. All plasmid constructs transformed to L. casei were unstable. The promoter designated lacA found to be the most efficient in reducing T-2 from the growth media of E. coli and L. lactis. A prompter library was generated from L. casei in order to isolate authentic probiotic promoters. Seven promoters were isolated, cloned downstream Tri101, transformed to bacteria and their detoxification capability was compared. One of those prompters, designated P201 showed a relatively high efficiency in detoxification. Sequence analysis of the promoter region of P201 and another promoter, P41, revealed the consensus region recognized by the sigma factor. We further attempted to isolate an inducible, strong promoter by comparing the protein profiles of L. casei grown in the presence of 0.3% bile salt (mimicking intestine conditions). Six spots that were consistently overexpressed in the presence of bile salts were isolated and identified. Their promoter reigns are now under investigation and characterization.