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1

Alves, Eliana, Felisa Rey, Tânia Melo, Madalena P. Barros, Pedro Domingues et Rosário Domingues. « Bioprospecting Bioactive Polar Lipids from Olive (Olea europaea cv. Galega vulgar) Fruit Seeds : LC-HR-MS/MS Fingerprinting and Sub-Geographic Comparison ». Foods 11, no 7 (25 mars 2022) : 951. http://dx.doi.org/10.3390/foods11070951.

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Olive seeds have been considered as a new nutritionally healthy food supplement. They are rich in monounsaturated n-9 and essential polyunsaturated n-6 lipids. However, little is known about their polar lipids, potentially bioactive and chemical identity markers for olive pulp and oil. This work aimed to identify the polar lipidome of olive seeds to find possible bioactive compounds and markers of geographic origin, by studying samples from six Portuguese sub-regions. Polar lipids were obtained by solid/liquid extraction, NH2-solid-phase extraction, and identified by hydrophilic interaction liquid chromatography (HILIC)-HR-ESI-MS and MS/MS. Ninety-four compounds were identified, including phospholipids, glycolipids, sphingolipids, and acyl sterol glycosides, several of which bear polyunsaturated fatty acids. Multivariate statistical analysis found unique profiles within each sub-region and markers of geographic identity, primarily phosphatidylcholines, phosphatidylethanolamines, and lysophosphatidylethanolamines. Therefore, polar lipid signatures should be further investigated, to assess their bioactivity, nutritional value, and chemical identity for valuing olive seeds and their oil.
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Pangle, Kevin L., Stuart A. Ludsin et Brian J. Fryer. « Otolith microchemistry as a stock identification tool for freshwater fishes : testing its limits in Lake Erie ». Canadian Journal of Fisheries and Aquatic Sciences 67, no 9 (septembre 2010) : 1475–89. http://dx.doi.org/10.1139/f10-076.

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We evaluated otolith chemistry as a tool for identifying natal origins of potamodromous fishes using historical Lake Erie water chemistry (1983–2001) and yellow perch ( Perca flavescens ) otolith elemental composition (1994–1996) data. Lake Erie’s tributaries had stream-specific chemical signatures that were temporally stable. Correspondingly, the otolith microelemental composition of larvae collected from tributary embayments (Sandusky and Maumee bays) was shown to be geographically distinct and the use of known-origin juveniles showed that larval otolith microelemental signatures could be used to accurately identify natal origins and indicate fish movement. Discrimination between offshore spawning locations was relatively difficult, however, indicating limitations to working in systems that are dominated by flow from a single large river (i.e., Detroit River). Interannual variability in otolith microelemental signatures was high such that larvae from one year could not reliably classify natal location of larvae in another year. Development of an annual library of site-specific signatures and exploration of complementary ways to discriminate natal origins would improve the use of otolith microchemistry as a fishery management tool in freshwater systems.
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Fernandes, Sara, André Gois, Fátima Mendes, Rosa Perestrelo, Sonia Medina et José S. Câmara. « Typicality Assessment of Onions (Allium cepa) from Different Geographical Regions Based on the Volatile Signature and Chemometric Tools ». Foods 9, no 3 (24 mars 2020) : 375. http://dx.doi.org/10.3390/foods9030375.

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Onion (Allium cepa L.) is one of the main agricultural commodities produced and consumed around the world. In the present work, for the first time, the volatile signature of onions from different geographical regions of Madeira Island (Caniço, Santa Cruz, Ribeira Brava, and Porto Moniz) was tested with headspace solid-phase microextraction (HS-SPME/GC-qMS) and chemometric tools, showing that the volatile signature was affected by the geographical region of cultivation. Sulfur compounds, furanic compounds, and aldehydes are the most dominant chemical groups. Some of the identified volatile organic metabolites (VOMs) were detected only in onions cultivated in specific regions; 17 VOMs were only identified in onions cultivated at Caniço, eight in Porto Moniz, two in Santa Cruz, two in Ribeira Brava, while 12 VOMs are common to all samples from the four regions. Moreover, some VOMs belonging to sulfur compounds (dipropyl disulfide, 3-(acetylthio)-2-methylfuran), furanic compounds (dimethylmethoxyfuranone, ethyl furanone, acetyloxy-dimethylfuranone), and lactones (whiskey lactone isomer), could be applied as potential geographical markers of onions, providing a useful tool to authenticate onions by farming regions where the influence of latitude seems to be an important factor for yielding the chemical profile and may contribute to geographical protection of food and simultaneously benefiting both consumers and farmers.
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Munro, Andrew R., Thomas E. McMahon et James R. Ruzycki. « Natural chemical markers identify source and date of introduction of an exotic species : lake trout (Salvelinus namaycush) in Yellowstone Lake ». Canadian Journal of Fisheries and Aquatic Sciences 62, no 1 (1 janvier 2005) : 79–87. http://dx.doi.org/10.1139/f04-174.

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Exotic species invasions pose a pervasive threat to aquatic ecosystems worldwide, yet fundamental questions about the geographic origin and timing of invasions or introductions are frequently difficult to answer. We used natural chemical markers (Sr:Ca ratios) in otoliths to identify probable source and date of introduction of exotic lake trout (Salvelinus namaycush) into Yellowstone Lake, Wyoming, USA. Otolith Sr:Ca ratios were significantly different among lake trout known to have reared in three different Yellowstone National Park lakes (Yellowstone, Heart, and Lewis lakes) and showed little variation along the otolith axis, indicating that lake trout within each lake experienced a similar, and consistent, environmental history. In contrast, suspected transplants showed a large and rapid increase in otolith Sr:Ca ratios indicative of a marked shift to water of differing chemistry. Timing of the abrupt change in Sr:Ca ratios indicated that some lake trout were introduced into Yellowstone Lake during the late 1980s, but more recent transplants also occurred. A discriminant model identified Lewis Lake as the likely source lake for lake trout transplanted into Yellowstone Lake. Our results demonstrate that chemical signatures within otoliths can serve as an important forensic tool for identifying the probable source and date of exotic fish introductions.
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Wang, Mei, Amar Chittiboyina, Jon Parcher, Zulfiqar Ali, Paul Ford, Jianping Zhao, Bharathi Avula, Yan-Hong Wang et Ikhlas Khan. « Piper nigrum Oil – Determination of Selected Terpenes for Quality Evaluation ». Planta Medica 85, no 03 (15 novembre 2018) : 185–94. http://dx.doi.org/10.1055/a-0782-0548.

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AbstractThe growing demand and commercial value of black pepper (Piper nigrum) has resulted in considerable interest in developing suitable and cost-effective methods for chemical characterization and quality evaluation purposes. In the current study, an extensive set of oil samples (n = 23) that were extracted by steam distillation from black pepper seeds was investigated to compare the chemical profiles of samples originating from nine major producing countries, as well as to identify potential chemical markers for quality evaluation. The twenty-two most abundant volatile compounds, mainly terpenes, in these oils were determined by conventional GC/MS analysis. Principal component analysis with this set of data revealed distinct clusters for samples that originated from China and Malaysia. Relatively low concentrations of sabinene (< 0.2%) and high concentrations of 3-carene (10.9 – 21.1%) were observed in these samples, respectively, compared to oil samples from other countries. The enantiomeric distributions of key terpene markers, viz., β-pinene, sabinene, limonene, and terpinen-4-ol, were determined by chiral GC/MS analysis. Interestingly, for these four monoterpenes, levo-isomers were found to be predominant, emphasizing the highly conserved enzymatic processes occurring in P. nigrum. Moreover, consistent enantiomeric ratios ((−) isomer/(+) isomer) of 92.2 ± 3.0% for β-pinene, 94.8 ± 2.8% for sabinene, 60.7 ± 1.1% for limonene, and 78.3 ± 1.3% for terpinen-4-ol were observed, independent of geographical location. These results demonstrate the potential of using stereospecific compositions as chiral signatures for establishing the authenticity and quality of black pepper oil.
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Célérier, Aurélie, Cécile Bon, Aurore Malapert, Pauline Palmas et Francesco Bonadonna. « Chemical kin label in seabirds ». Biology Letters 7, no 6 (27 avril 2011) : 807–10. http://dx.doi.org/10.1098/rsbl.2011.0340.

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Chemical signals yield critical socio-ecological information in many animals, such as species, identity, social status or sex, but have been poorly investigated in birds. Recent results showed that chemical signals are used to recognize their nest and partner by some petrel seabirds whose olfactory anatomy is well developed and which possess a life-history propitious to olfactory-mediated behaviours. Here, we investigate whether blue petrels ( Halobaena caerulea ) produce some chemical labels potentially involved in kin recognition and inbreeding avoidance. To overcome methodological constraints of chemical analysis and field behavioural experiments, we used an indirect behavioural approach, based on mice olfactory abilities in discriminating odours. We showed that mice (i) can detect odour differences between individual petrels, (ii) perceive a high odour similarity between a chick and its parents, and (iii) perceive this similarity only before fledging but not during the nestling developmental stage. Our results confirm the existence of an individual olfactory signature in blue petrels and show for the first time, to our knowledge, that birds may exhibit an olfactory kin label, which may have strong implications for inbreeding avoidance.
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Slaghenaufi, Davide, Giovanni Luzzini, Jessica Samaniego Solis, Filippo Forte et Maurizio Ugliano. « Two Sides to One Story—Aroma Chemical and Sensory Signature of Lugana and Verdicchio Wines ». Molecules 26, no 8 (7 avril 2021) : 2127. http://dx.doi.org/10.3390/molecules26082127.

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Lugana and Verdicchio are two Italian white wines with a Protected Designation of Origin (PDO) label. These two wine types are produced in different regions using the same grape variety. The aim of this work is to investigate the existence of volatile chemical markers that could help to elucidate differences between Lugana and Verdicchio wines both at chemical and sensory levels. Thirteen commercial wine samples were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS), and 76 volatile compounds were identified and quantified. Verdicchio and Lugana had been differentiated on the basis of 19 free and glycosidically bound compounds belonging to the chemical classes of terpenes, benzenoids, higher alcohols, C6 alcohols and norisoprenoids. Samples were assessed by means of a sorting task sensory analysis, resulting in two clusters formed. These results suggested the existence of 2 product types with specific sensory spaces that can be related, to a good extend, to Verdicchio and Lugana wines. Cluster 1 was composed of six wines, 4 of which were Lugana, while Cluster 2 was formed of 7 wines, 5 of which were Verdicchio. The first cluster was described as “fruity”, and “fresh/minty”, while the second as “fermentative” and “spicy”. An attempt was made to relate analytical and sensory data, the results showed that damascenone and the sum of 3 of esters the ethyl hexanoate, ethyl octanoate and isoamyl acetate, was characterizing Cluster 1. These results highlighted the primary importance of geographical origin to the volatile composition and perceived aroma of Lugana and Verdicchio wines.
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Nataningtyas, Dilin Rahayu, Tri Joko Raharjo et Endang Astuti. « Three Dimensional Structural Modelling of Lipase Encoding Gene from Soil Bacterium Alcaligenes sp. JG3 Using Automated Protein Homology Analysis ». Indonesian Journal of Chemistry 19, no 3 (29 mai 2019) : 565. http://dx.doi.org/10.22146/ijc.34152.

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Bacterial lipases have significant potential to be used as the biocatalyst for many chemical reactions. In this study, a novel gene encoding lipase was isolated from an Alcaligenes sp. JG3. A pair of designed primer has successfully isolated 1 kb (LipJG3) that shares 98% identity towards lipase from Alcaligenes faecalis during sequence analysis. By using in silico tools, LipJG3 was related to the transporter protein sequences. Three highly conserved regions consisting of EASGSKT, VILLD, and LSGGQQQRVAIA were found. These regions were known as ATP-binding signature at Walker-A and Walker-B motifs and the S signature of ABC transporter family respectively. In addition, the 3-D structure of LipJG3 has been suggested but the role of the catalytic triad residues have been not fully understood.
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Takahashi, Yuya, Xiang-Hua Li, Chigen Tsukamoto et Ke-Jing Wang. « Phenotypic and genotypic signature of saponin chemical composition in Chinese wild soybean (Glycine soja) : revealing genetic diversity, geographical variation and dispersal history of the species ». Crop and Pasture Science 69, no 11 (2018) : 1126. http://dx.doi.org/10.1071/cp18214.

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Saponin chemical composition was phenotyped and genotyped, and saponin composition-based geographical genetic diversity and differentiation were evaluated in Chinese wild soybean (Glycine soja Sieb. & Zucc.). Thirty-two phenotypes and 34 genotypes were confirmed from 3805 wild soybean accessions. Eleven phenotypes (AaαK, AaαIK, AaαIJK, AaBcEαJ, AaBcαK, AbEαIJ, AbαK, AbαIK, AbαIJK, AbβHAb and Aβ0) were newly detected. Four genes had frequencies: Sg-1a 78.8% and Sg-1b 21.0% at the Sg-1 locus; Sg-4 30.7% and Sg-6e 13.7% at their respective loci. The north-eastern and southern populations showed high genetic diversity; the Northeast region contained more novel variants (AuAe, A0, A0Bc, αH, αI αJ, αK, and AbβHAb), and the southern populations contained high frequencies of the Sg-4 gene. Gene differentiation (Fst) analysis suggested that Sg-4 and four group-α saponin alleles or genes (Sg-6e, Sg-6h, Sg-6i, Sg-6j) were important factors influencing the genetic structure and differentiation in Chinese wild soybeans. Geographical differentiation was characterised mainly by latitudinal differences, with two primary groups (north and south) based on saponin genes. Chinese wild soybean accessions differed from Japanese and South Korean ones in genetic structure based on saponin composition, the latter two being likely to have spread from southern China in the glacial stages during the last Ice Age.
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Brodie, Christopher, Oliver Kracht et Andreas Hilkert. « Tracing the Geographical Origin of Roasted and Green Coffee Using Isotope Fingerprints ». Journal of AOAC INTERNATIONAL 102, no 2 (1 mars 2019) : 653–54. http://dx.doi.org/10.5740/jaoacint.18-0314.

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Abstract Background: Coffee is one of the most popular beverages worldwide, sourced from different geographical regions. To ensure that coffeebeans come from labelled locations, laboratories need an analytical solution that can discriminate geographical origin. Coffee beans have a fingerprint, a unique chemical signature that allows them to be identified: Isotope fingerprints of carbon, nitrogen, sulfur, hydrogen, and oxygen have been reliably used for origin claim verification. Objective: Show that hydrogen and oxygen isotope fingerprints from green and roasted coffee beans can determine the origin of coffee beans. Methods: The coffee beans were initially ground to as fine as possible a powder using a cryo-mill. Following, samples were weighed into tin capsules and introduced to the Thermo Scientific EA IsoLink™ IRMS System via the Thermo Scientific MAS Plus autosampler, where they were pyrolyzed at 1450°C, and converted to H2 and CO for analysis. Results: The hydrogen and oxygen isotope fingerprints of the coffee beans show that they can be clearly differentiated at the continent scale. Conclusions: It is evident that measuring the isotope fingerprint of coffee beans helps support legislation on food integrity and labelling (EC Reg. No. 1169/2011) and product geographical indication/origin (EC Reg. No. 510/2006), therefore protecting consumers and brands. The origin of a coffee bean can be determined using their hydrogen and oxygen isotope fingerprints. Highlights: Hydrogenand oxygen isotope fingerprints can help determine the origin of coffee beans, allowing the label claim to be verified.
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White, Cindel J. M., Michael Muthukrishna et Ara Norenzayan. « Cultural similarity among coreligionists within and between countries ». Proceedings of the National Academy of Sciences 118, no 37 (7 septembre 2021) : e2109650118. http://dx.doi.org/10.1073/pnas.2109650118.

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Cultural evolutionary theories suggest that world religions have consolidated beliefs, values, and practices within a superethnic cultural identity. It follows that affiliation with religious traditions would be reliably associated with global variation in cultural traits. To test this hypothesis, we measured cultural distance between religious groups within and between countries, using the Cultural Fixation Index (CFST) applied to the World Values Survey (88 countries, n = 243,118). Individuals who shared a religious tradition and level of commitment to religion were more culturally similar, both within and across countries, than those with different affiliations and levels of religiosity, even after excluding overtly religious values. Moreover, distances between denominations within a world religion echoed shared historical descent. Nonreligious individuals across countries also shared cultural values, offering evidence for the cultural evolution of secularization. While nation-states were a stronger predictor of cultural traits than religious traditions, the cultural similarity of coreligionists remained robust, controlling for demographic characteristics, geographic and linguistic distances between groups, and government restriction on religion. Together, results reveal the pervasive cultural signature of religion and support the role of world religions in sustaining superordinate identities that transcend geographical boundaries.
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Gupta, Vijeta, Dr Tarun Virmani et Dr Vijender Singh. « A Comparative Diagnostic account of the Roots of Boerhavia diffusa Linn. From Four Different Geographical Regions in India ». Journal of Community Pharmacy Practice, no 23 (27 mai 2022) : 1–6. http://dx.doi.org/10.55529/jcpp.23.1.6.

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Boerhavia diffusa Linn (B. diffusa) belongs to the family Nyctaginaceae, commonly referred to as Punarnava. It is a rasayana plant that has anti-aging, disease prevention and life-building activities. In this study, B. diffusa Linn’s roots were collected from four different geographical locations in Indian territory i.e. Jhansi, Bangalore, Punjab and Delhi for comparative standardization. The study was carried out in accordance with WHO guidelines to determine the purity and correct identity of plant parts. It also helps detect adulterations, botanical verification, and physical and chemical parameters, and gives the notion of drug quality. In the present work, detailed comparative Pharmacognosy, morphology, anatomy and phytochemical studies of root of B.diffusa Linn from Four different geographical regions in India have been carried out. The results show that all four B.diffusa from different geographical regions revealed that all are very distinct. The anatomical parameters and physicochemical constants carried out in the present investigation serves as measures of a quality control for all the four plants i.e; Boerhavia diffusa Linn.(Jhansi, Bangalore, Pune and Delhi).
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Ahmed, Adel A., et Omar M. Barukab. « Unforgeable Digital Signature Integrated into Lightweight Encryption Based on Effective ECDH for Cybersecurity Mechanism in Internet of Things ». Processes 10, no 12 (7 décembre 2022) : 2631. http://dx.doi.org/10.3390/pr10122631.

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Cybersecurity protocols enable several levels of protection against cyberattacks (digital attacks) that spread across network devices, platform programs, and network applications. On the Internet of Things (IoT), cyberattacks are generally intended to access and change/destroy sensitive information, which may reduce IoT benefits. Moreover, recent IoT systems are experiencing a critical challenge in designing a lightweight and robust cybersecurity mechanism on resource-constrained IoT devices. The cybersecurity challenges facing the IoT that should be taken into consideration are identifying compromised devices, data/service protection, and identifying impacted IoT users. This paper proposes an unforgeable digital signature integrated into an effective lightweight encryption (ELCD) mechanism that utilizes the secure key distribution in an elliptic curve Diffie–Hellman (ECDH) and resolves the weak bit problem in the shared secret key due to the Diffie–Hellman exchange. The ELCD mechanism proposes a secure combination between the digital signature and encryption, and it uses fast hash functions to confidentially transfer a shared secret key among IoT devices over an insecure communication channel. Furthermore, the ELCD mechanism checks the true identity of the sender with certainty through the proposed digital signature, which works based on a hash function and three steps of curve-point inspection. Furthermore, the security of ELCD was mathematically proven using the random oracle and IoT adversary models. The findings of the emulation results show the effectiveness of ELCD in terms of CPU execution time, storage cost, and power consumption that are less by 53.8%, 33–17%, and 68.7%, respectively, compared to the baseline cryptographic algorithms.
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Négrel, Philippe, Anna Ladenberger, Clemens Reimann, Alecos Demetriades, Manfred Birke et Martiya Sadeghi. « GEMAS : adaptation of weathering indices for European agricultural soil derived from carbonate parent materials ». Geochemistry : Exploration, Environment, Analysis 22, no 1 (2 décembre 2021) : geochem2021–059. http://dx.doi.org/10.1144/geochem2021-059.

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Carbonate rocks are very soluble and export elements in dissolved form, and precipitation of secondary phases can occur on a large scale. They leave a strong chemical signature in soil that can be quantified and classified by geochemical indices, and which is useful for evaluating chemical weathering trends (e.g. the Chemical Index of Alteration (CIA) or the Mafic Index of Alteration (MIA)). Due to contrasting chemical compositions and high Ca content, a special adaptation of classical weathering indices is necessary to interpret weathering trends in carbonate-derived soil. In fact, this adaptation seems to be a good tool for distinguishing weathering grades of source-rock types at the continental scale, and allows a more robust interpretation of soil parent-material weathering grade and its impact on the current chemical composition of soil. An increasing degree of weathering results in Al enrichment and Mg loss in addition to Fe loss and Si enrichment, leaching of mobile cations such as Ca and Na, and precipitation of Fe-oxides and hydroxides. The relation between soil weathering status and its spatial distribution in Europe provides important information about the role played by climate and terrain. The geographical distribution of soil chemistry contributes to a better understanding of soil nutritional status, element enrichment, degradation mechanisms, desertification, soil erosion and contamination.
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Digonnet, Stéphane, Normand Goulet, James Bourne, Ross Stevenson et Doug Archibald. « Petrology of the Abloviak Aillikite dykes, New Québec : evidence for a Cambrian diamondiferous alkaline province in northeastern North America ». Canadian Journal of Earth Sciences 37, no 4 (3 avril 2000) : 517–33. http://dx.doi.org/10.1139/e00-008.

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A dozen ultramafic lamprophyre dykes have been identified in the eastern part of Ungava Bay, Québec. The dark grey dykes are composed of macrocrysts of olivine and phlogopite featuring tetraferriphlogopite rims. These minerals are included in a matrix consisting of fine-grained phlogopite, olivine, spinel, and interstitial carbonate. The geochemical composition, mineral assemblage, chemical analyses of the xenocrysts and phenocrysts and Sm-Nd isotopic signature indicate that these rocks are carbonated ultramafic lamprophyre dykes. The chemical zonation of the micas and the presence of andradite suggest a complex sequence of crystallization. An Ar isotope correlation analysis indicates an age of approximately 550 Ma. The dykes have intruded the Tasiuyak gneiss, a suite of Paleoproterozoic metasedimentary rocks. This unit occupies the Torngat Orogen collision zone between the Rae Province and the Nain Province. The dykes are considered to have been emplaced within tension gashes during reactivation of major Paleoproterozoic structures and fractures associated with the opening of the Iapetus Ocean. They are possibly related to a mantle plume that simultaneously caused both the rupture of the Laurentia and the formation of the ultramafic magma. The Abloviak lamprophyres have quite similar analogues in southwest Greenland. The age, geochemical characteristics, isotopic signature common to all these dykes, the geological environment of the southwest Greenland are all comparable with the data presented here for the Abloviak lamprophyres. Furthermore their pre-drift geographical proximity, prior to the opening of the Labrador Sea, suggests that they are related to a common magmatic event which constitutes a diamondiferous alkaline province located in northeastern North America.
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Reed, D. A., S. Toze et B. Chang. « Spatial and temporal changes in sulphate-reducing groundwater bacterial community structure in response to Managed Aquifer Recharge ». Water Science and Technology 57, no 5 (1 avril 2008) : 789–95. http://dx.doi.org/10.2166/wst.2008.172.

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The population dynamics of bacterial able to be cultured under sulphate reducing condition was studied in conjunction with changes in aquifer geochemistry using multivariate statistics for two contrasting Managed Aquifer Recharge (MAR) techniques at two different geographical locations (Perth, Western Australia and Adelaide, South Australia). Principal component analysis (PCA) was used to investigate spatial and temporal changes in the overall chemical signature of the aquifers using an array of chemical analytes which demonstrated a migrating geochemical plume. Denaturing Gradient Gel Electrophoresis (DGGE) using DNA from sulphate-reducing bacteria cultures was used to detect spatial and temporal changes in population dynamics. Bacterial and geochemical evidence suggested that groundwater at greatest distance from the nutrient source was least affected by treated effluent recharge. The results suggested that bacterial populations that were able to be cultured in sulphate reducing media responded to the migrating chemical gradient and to the changes in aquifer geochemistry. Most noticeably, sulphate-reducing bacterial populations associated with the infiltration galleries were stable in community structure over time. Additionally, the biodiversity of these culturable bacteria was restored when aquifer geochemistry returned to ambient conditions during the recovery phase at the Adelaide Aquifer Storage and Recovery site.
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Boichu, Marie, Olivier Favez, Véronique Riffault, Jean-Eudes Petit, Yunjiang Zhang, Colette Brogniez, Jean Sciare et al. « Large-scale particulate air pollution and chemical fingerprint of volcanic sulfate aerosols from the 2014–2015 Holuhraun flood lava eruption of Bárðarbunga volcano (Iceland) ». Atmospheric Chemistry and Physics 19, no 22 (27 novembre 2019) : 14253–87. http://dx.doi.org/10.5194/acp-19-14253-2019.

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Abstract. Volcanic sulfate aerosols play a key role in air quality and climate. However, the rate of oxidation of sulfur dioxide (SO2) precursor gas to sulfate aerosols (SO42-) in volcanic plumes is poorly known, especially in the troposphere. Here we determine the chemical speciation as well as the intensity and temporal persistence of the impact on air quality of sulfate aerosols from the 2014–2015 Holuhraun flood lava eruption of Icelandic volcano Bárðarbunga. To do so, we jointly analyse a set of SO2 observations from satellite (OMPS and IASI) and ground-level measurements from air quality monitoring stations together with high temporal resolution mass spectrometry measurements of an Aerosol Chemical Speciation Monitor (ACSM) performed far from the volcanic source. We explore month/year long ACSM data in France from stations in contrasting environments, close and far from industrial sulfur-rich activities. We demonstrate that volcanic sulfate aerosols exhibit a distinct chemical signature in urban/rural conditions, with NO3:SO4 mass concentration ratios lower than for non-volcanic background aerosols. These results are supported by thermodynamic simulations of aerosol composition, using the ISORROPIA II model, which show that ammonium sulfate aerosols are preferentially formed at a high concentration of sulfate, leading to a decrease in the production of particulate ammonium nitrate. Such a chemical signature is however more difficult to identify at heavily polluted industrial sites due to a high level of background noise in sulfur. Nevertheless, aged volcanic sulfates can be distinguished from freshly emitted industrial sulfates according to their contrasting degree of anion neutralization. Combining AERONET (AErosol RObotic NETwork) sunphotometric data with ACSM observations, we also show a long persistence over weeks of pollution in volcanic sulfate aerosols, while SO2 pollution disappears in a few days at most. Finally, gathering 6-month long datasets from 27 sulfur monitoring stations of the EMEP (European Monitoring and Evaluation Programme) network allows us to demonstrate a much broader large-scale European pollution, in both SO2 and SO4, associated with the Holuhraun eruption, from Scandinavia to France. While widespread SO2 anomalies, with ground-level mass concentrations far exceeding background values, almost entirely result from the volcanic source, the origin of sulfate aerosols is more complex. Using a multi-site concentration-weighted trajectory analysis, emissions from the Holuhraun eruption are shown to be one of the main sources of SO4 at all EMEP sites across Europe and can be distinguished from anthropogenic emissions from eastern Europe but also from Great Britain. A wide variability in SO2:SO4 mass concentration ratios, ranging from 0.8 to 8.0, is shown at several stations geographically dispersed at thousands of kilometres from the eruption site. Despite this apparent spatial complexity, we demonstrate that these mass oxidation ratios can be explained by a simple linear dependency on the age of the plume, with a SO2-to-SO4 oxidation rate of 0.23 h−1. Most current studies generally focus on SO2, an unambiguous and more readily measured marker of the volcanic plume. However, the long persistence of the chemical fingerprint of volcanic sulfate aerosols at continental scale, as shown for the Holuhraun eruption here, casts light on the impact of tropospheric eruptions and passive degassing activities on air quality, health, atmospheric chemistry and climate.
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Sofińska, Kamila, Natalia Wilkosz, Marek Szymoński et Ewelina Lipiec. « Molecular Spectroscopic Markers of DNA Damage ». Molecules 25, no 3 (28 janvier 2020) : 561. http://dx.doi.org/10.3390/molecules25030561.

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Every cell in a living organism is constantly exposed to physical and chemical factors which damage the molecular structure of proteins, lipids, and nucleic acids. Cellular DNA lesions are the most dangerous because the genetic information, critical for the identity and function of each eukaryotic cell, is stored in the DNA. In this review, we describe spectroscopic markers of DNA damage, which can be detected by infrared, Raman, surface-enhanced Raman, and tip-enhanced Raman spectroscopies, using data acquired from DNA solutions and mammalian cells. Various physical and chemical DNA damaging factors are taken into consideration, including ionizing and non-ionizing radiation, chemicals, and chemotherapeutic compounds. All major spectral markers of DNA damage are presented in several tables, to give the reader a possibility of fast identification of the spectral signature related to a particular type of DNA damage.
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Uchimiya, Minori, Anthony G. Hay et Jeffrey LeBlanc. « Chemical and microbial characterization of sugarcane mill mud for soil applications ». PLOS ONE 17, no 8 (16 août 2022) : e0272013. http://dx.doi.org/10.1371/journal.pone.0272013.

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Sugarcane mill mud/filter cake is an activated sludge-like byproduct from the clarifier of a raw sugar production factory, where cane juice is heated to ≈90°C for 1–2 hr, after the removal of bagasse. Mill mud is enriched with organic carbon, nitrogen, and nutrient minerals; no prior report utilized 16S rRNA gene sequencing to characterize the microbial composition. Mill mud could be applied to agricultural fields as biofertilizer to replace or supplement chemical fertilizers, and as bio-stimulant to replenish microorganisms and organic carbon depleted by erosion and post-harvest field burning. However, mill mud has historically caused waste management challenges in the United States. This study reports on the chemical and microbial (16S rRNA) characteristics for mill muds of diverse origin and ages. Chemical signature (high phosphorus) distinguished mill mud from bagasse (high carbon to nitrogen (C/N) ratio) and soil (high pH) samples of diverse geographical/environmental origins. Bacterial alpha diversity of all sample types (mill mud, bagasse, and soil) was inversely correlated with C/N. Firmicutes dominated the microbial composition of fresh byproducts (mill mud and bagasse) as-produced within the operating factory. Upon aging and environmental exposure, the microbial community of the byproducts diversified to resemble that of soils, and became dominated by varying proportions of other phyla such as Acidobacteria, Chloroflexi, and Planctomyces. In summary, chemical properties allowed grouping of sample types (mill mud, bagasse, and soil-like), and microbial diversity analyses visualized aging caused by outdoor exposures including soil amendment and composting. Results suggest that a transient turnover of microbiome by amendments shifts towards more resilient population governed by the chemistry of bulk soil.
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Sharma, Shiv Narayan, Zenu Jha et D. K. Sharma. « Chemometrics Evaluation of the Herbal Drug Andrographis paniculata ». Natural Product Communications 6, no 12 (décembre 2011) : 1934578X1100601. http://dx.doi.org/10.1177/1934578x1100601235.

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A fingerprint was developed to evaluate ten genotypes of Andrographis paniculata (a herbal drug) collected from different geographical locations. The genotypes were assessed by HPLC and the chromatogram areas were used to construct fingerprints. Between the two fingerprints, vector of differences was defined. The scalar mean of the deviated vector was used for statistical analysis. By incorporating appropriate chemometric methods better differentiation of samples was achieved. This provides tools for extracting relevant chemical information from the obtained data. The developed method can be used as a quality control tool for rapid authentication, identity, assessment and selection of good quality natural drug from a wide variety of herbal samples.
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STOICA, FELICIA, RALUCA POPESCU et BOGDAN COSTEA. « STUDIES ON THE QUALITY AND AUTHENTICITY OF WHITE WINES FROM OLTENIA ». "Annals of the University of Craiova - Agriculture, Montanology,Cadastre Series " 51, no 1 (18 décembre 2020) : 167–72. http://dx.doi.org/10.52846/aamc.2021.01.21.

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For white wines, in addition to the level of the main chemical constituents defined for each category and type, the properties of fruitiness, aroma and expressiveness, typical of varieties and areas of origin, are fundamental quality criteria. In addition, these products must be offered to consumers in a perfect state of clarity and with lasting stability over time. The capitalization of the viticultural potential that Romania has, in order to obtain sustainable competitive advantages on foreign markets, requires the creation and promotion of an identity of Romanian wine, based on analytical investigations to certify the quality and natural chemical composition of wines. Determining the quality and authentication of wines involves several aspects, such as geographical origin, year of production, variety, producer and quality. It is important that the proof of the authenticity of the wine is based on those chemical parameters that do not change during vinification process or that are difficult to falsify
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Areni, Alesssndra, Gilda Sensales et Angela Angelastro. « Le rivolte francesi del novembre 2005 nei titoli di ventuno quotidiani italiani. Ricostruzione dei processi rappresentazionali attraverso un'analisi lessicografica ». RICERCHE DI PSICOLOGIA, no 4 (mai 2009) : 31–58. http://dx.doi.org/10.3280/rip2008-004002.

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- The tradition of the social representations is the framework of research that is part of a wider project focused on the role of mass media, as part of cultural system, and on processes of anchorage and labelling involved to define the events under observation. We studied the social representations of French riots of November 2005 on headlines of 21 Italian daily newspapers with different cultural and ideological orientation. The aims of research, of comparative character, were the exploration: of consistence of results emerged in previous investigations, and of role played from newspapers and from temporal distance by the events 1) on structural organization of representational field, related to lexicon of headlines, and 2) on differential characterization of the lexicon of headlines 2a) of 21 newspapers and 2b) of two periods, more or less near to the beginning of events. The population, composed by 468 headlines, was collected by October 30 to November 18, 2005. The textual data, related to words of headlines, and the extra-textual data, related to newspapers, to period of publication (I and II week), to signature and sex of journalists, have been processed by different steps of statistical package SPAD-T. According to the scree-test were extracted two factors able to explain 20.40% of total variance. Through the intersection between the two factors we analyzed the factorial plan that, by providing the information more synthetic and exhaustive as possible, highlighted the existence of four areas otherwise characterized by the newspapers, by the two weeks and by the signature and gender of journalists. The differential analysis of lexicographical characterization of each of the 21 newspapers and of two periods, allowed the confirmation and deepening of what emerged in the structural analysis. Overall results showed the non-neutrality of language used by the headlines. It was functional to ideological and cultural profile of source, to its geographical area of reference and to temporal distance from origin of events. Furthermore results showed processes of anchorage and la- beling referable to need to preserve and strengthen specific groupal identity of the source.
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Ferretti, Carlo G., et Stefano Febbroni. « Terroir Traceability in Grapes, Musts and Gewürztraminer Wines from the South Tyrol Wine Region ». Horticulturae 8, no 7 (28 juin 2022) : 586. http://dx.doi.org/10.3390/horticulturae8070586.

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This study arose from the need to relate specific terroir aspects with experienced sensory properties of Gewürztraminer wines from Tramin (northern Italy). A multidisciplinary approach was used to investigate seven vineyards’ ecological characteristics, including geology and geographical features. A geopedological method using Vineyard Geological Identity (VGI) and Solar Radiation Identity (SRI) for topoclimatic classification, as well as multi-parameter measuring stations of air and soils, elicited analytical data for qualitative and quantitative terroir characterisations. Furthermore, wide-ranging and targeted oenological and chemical analyses were conducted on grapes, musts and wines to correlate their biochemical compositions with the measured terroir conditions. The study identified strong connections between vineyard geo-identity and wine mineral fingerprint, confirming mineral traceability of Rb/Sr ratio and of some minerals common to the local geology, such as Ba, Rb, Mn and Be. In particular, the most differing geo-mineral and physical soil conditions of two studied vineyards are apparent in the oenological components, flavours and aromas of their musts and finished wines. Amino acids, primary varietal aromas and polyphenols, thiol compounds with tropical scents, phenolic compounds with spicy notes and terpenic compounds, such as geraniol and citronellol, were related differently between fine-textured, more siliceous soils of glacial origin and coarser-textured, more dolomitic soils of local debris flow origin.
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K. Sudharani, Ms, et Dr N. K. Sakthivel. « Design and development of a secure certificateless proxy signature based (SE-CLPS) encryption scheme for cloud storage ». International Journal of Engineering & ; Technology 10, no 1 (19 février 2021) : 57. http://dx.doi.org/10.14419/ijet.v10i1.21480.

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Certificateless Public Key Cryptography (CL-PKC) scheme is a new standard that combines Identity (ID)-based cryptography and tradi- tional PKC. It yields better security than the ID-based cryptography scheme without requiring digital certificates. In the CL-PKC scheme, as the Key Generation Center (KGC) generates a public key using a partial secret key, the need for authenticating the public key by a trusted third party is avoided. Due to the lack of authentication, the public key associated with the private key of a user may be replaced by anyone. Therefore, the ciphertext cannot be decrypted accurately. To mitigate this issue, an Enhanced Certificateless Proxy Signature (E-CLPS) is proposed to offer high security guarantee and requires minimum computational cost. In this work, the Hackman tool is used for detecting the dictionary attacks in the cloud. From the experimental analysis, it is observed that the proposed E-CLPS scheme yields better Attack Detection Rate, True Positive Rate, True Negative Rate and Minimum False Positives and False Negatives than the existing schemes.
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Hare, James F. « Discrimination of nestmate larvae by the ant Leptothorax longispinosus ». Canadian Journal of Zoology 74, no 11 (1 novembre 1996) : 2055–61. http://dx.doi.org/10.1139/z96-233.

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Laboratory colonies of the ant Leptothorax longispinosus were presented with 10 larvae each from their own nest, conspecific larvae from a nest collected from the same site of origin, and conspecific larvae from a nest collected from another site in the same geographical region. Workers preferentially retrieved larvae from their own nest over those from nests obtained at the same site and other sites. Non-nestmate larvae from the same site were not preferred over those originating from other collection sites. Thus, L. longispinosus workers discriminate among conspecific larvae and preferentially retrieve nestmate larvae. Results of experiments involving CO2-anaesthetized larvae or larva-sized silicone "baits" suggest that the discriminator substances underlying nestmate larva recognition are chemical in nature and are borne on the larval cuticle. Further, those chemical attractants are present on material found within the ant's nest. In a final series of experiments, nestmate larvae were placed in contact with non-nestmate conspecific larvae or with larvae of a congener (Leptothorax ambiguus). Again workers preferred nestmate larvae, and preferred conspecific over allospecific larvae. However, there was no evidence that contact with nestmate larvae enhanced the acceptance of either conspecific or allospecific larvae, nor that contact with non-nestmate larvae diminished the acceptability of actual nestmate larvae. These findings suggest that any cues transferred via contact are insufficient to overwhelm a larva's own underlying recognition signature or that workers selectively attend to familiar cues.
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Dr. Raed Mohammad Flieh Alnimer, Dr Yassin Ahmad alqudah,. « The Legal Nature of the Electronic Contract (comparative study) ». Psychology and Education Journal 58, no 1 (1 janvier 2021) : 2260–76. http://dx.doi.org/10.17762/pae.v58i1.1104.

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There is no doubt that the huge development in the revolution of communications and modern technologies in addition to modern technological development in general led to the emergence of electronic commerce through which the electronic contract. It is necessary to shed light on this modern type of transaction to clarify the nature of the laws and provisions that govern it, so as to provide legal protection for the clients in this field. For this reason, I have considered dealing with this area, which will require legal systems to be subject to the provisions and laws necessary to settle disputes that may arise, and to high light on the nature of the electronic contract by holding it and proving it only. The Internet has been one of the most important innovations of the human mind in the field of informatics since the end of the last century. It removed geographical boundaries between countries and helped to turn the world into a small village and developed e-commerce. The Internet is one of the most important means through which Conclusion of electronic contracts. The electronic contract is validated by verifying the validity of the pillars: the object, the cause, the agreement and the eligibility, which are organized in the same framework as the general rules regulating the traditional contract. With some specificity of these pillars, the scope of the general rules is not broadened; to accommodate the eligibility of the contractors, it is difficult to ascertain the identity of the contracting parties and their eligibility, electronic signature and certification to try and fill gaps in this range.
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Carvalho, Aline Gabrielle Alves de, Lucía Olmo-García, Bruna Rachel Antunes Gaspar, Alegría Carrasco-Pancorbo, Vanessa Naciuk Castelo-Branco et Alexandre Guedes Torres. « Preliminary Discrimination of Commercial Extra Virgin Olive Oils from Brazil by Geographical Origin and Olive Cultivar : A Call for Broader Investigations ». Proceedings 70, no 1 (9 novembre 2020) : 57. http://dx.doi.org/10.3390/foods_2020-07664.

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Extra virgin olive oil (EVOO) production in Brazil has been recently established and is growing, but only a few studies have been published on the topic, particularly involving commercial EVOO samples. A preliminary discrimination of Brazilian EVOOs according to olive cultivar and region of production was conducted. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were performed based on the results of recent published work by our research group on the evaluation of the quality parameters, the metabolic profile, and other typical features of commercial EVOOs from Brazil. One of the oleuropein aglycone isomers, linoleic acid, α-tocopherol, and free sterols were found to be the most discriminating variables within the models. PLS-DA also revealed the region of production as a significant factor in samples’ clustering. The present work provides a preview of Brazilian EVOOs typicity and discloses the urge for further investigations with a higher number of commercial samples, from different olive cultivars and production regions. The comprehensive definition of the identity of their chemical profiles could provide Brazilian oils with a significant added value, and possibly show distinctive features that could motivate the future establishment of protected designation of origin.
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Sokoloff, Dmitry D., Margarita V. Remizowa, Maxim S. Nuraliev, Leonid V. Averyanov et Alexander N. Sennikov. « The First Genome from the Basal Monocot Family Has Been Misnamed : Taxonomic Identity of Acorus tatarinowii (Acoraceae), a Source of Numerous Chemical Compounds of Pharmaceutical Importance ». Diversity 15, no 2 (26 janvier 2023) : 176. http://dx.doi.org/10.3390/d15020176.

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The basalmost monocot genus Acorus is well-known for its use in traditional oriental medicine. It comprises the groups of A. calamus and A. gramineus. A recent study recognized three species in the latter group, A. gramineus, A. macrospadiceus, and A. tatarinowii. The material currently known as A. tatarinowii has been extensively studied as a source of various chemical compounds and for producing the first published genome of Acorus, which is important for understanding the origin and evolution of monocots. Using the data from morphology, anatomy, and biogeography, we argue that the type material of A. tatarinowii does not match the interpretation of the species name as adopted in the current literature and herbarium collections (to a taxon of the A. gramineus group from Southeast Asia) but rather belongs to the A. calamus group. Moreover, the name A. macrospadiceus also cannot be used because it was invalidly published. Under a narrow species concept, other appropriate species names should be found or proposed for the plants currently named A. tatarinowii and A. macrospadiceus. However, we discourage the use of a narrow species concept in the A. gramineus group as insufficiently justified and suggest recognizing a single polymorphic species, A. gramineus s.l., at least until a comprehensive taxonomic revision of the group is available. Apart from the presentation of our revised taxonomic framework, we update the geographical distributions of Acorus species in Vietnam, Laos, and Thailand.
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Dorais, Michael John, Wallace Bothner et Robert Buchwaldt. « The Appledore Island pluton of the Rye Complex, coastal New Hampshire and Maine, USA : geochronological and chemical evidence for the affinity of an enigmatic terrane ». Atlantic Geology 50 (18 octobre 2014) : 138. http://dx.doi.org/10.4138/atlgeol.2014.009.

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The Rye Complex of coastal New Hampshire and Maine is a peri-Gondwanan terrrane that up to now had an uncertain origin. An offshore portion of the complex, Appledore Island of the Isles of Shoals, hosts a mainly dioritic intrusion that yielded an U-Pb zircon age of 361.09 ± 0.14 Ma, allowing comparison of its geochemical characteristics with mafic rocks of similar age across the northern Appalachian orogen. The Appledore Island diorite has similar major, trace, and isotopic compositions as continental rift tholeiite in the Narragansett Basin in southern New England and in the Maritimes Basin of Canada. These intraplate volcanic rocks range from 375 to 330 Ma, bracketing the age of the Appledore Island diorite. Their intraplate tectonic setting reflects regional extension during the Late Devonian to Early Carboniferous which produced successor basins after the Acadian orogeny. The geochemical and age similarities of the Appledore Island diorite and the mafic rocks of the successor basins suggest that the Rye Complex is a basement fragment of a successor basin block. Further evidence of the identity of the Rye Complex is provided by the isotopic composition of intermingled, comagmatic granitic rocks associated with the Appledore Island diorite. The granite has a Ganderian isotopic signature, suggesting that the Rye Complex is a Ganderian basement block that was transposed by movement along the Norumbega Fault System to its position adjacent to the Merrimack Trough of New Hampshire and Maine.
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Mancilla, Yasmany, Gerardo Medina, Lucy T. González et Alberto Mendoza. « FINE PARTICLES EMISSION SOURCE PROFILES FOR A SEMI-ARID URBAN CENTER : KEY MARKERS AND SIMILARITY TESTS ». Revista Internacional de Contaminación Ambiental 38 (7 mars 2022) : 57–80. http://dx.doi.org/10.20937/rica.54132.

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Source apportionment studies rely on source emission profiles, which in some instances are locally scarce or non-existent. Thus, estimations are done using profiles obtained from other geographical sites, which brings a certain degree of uncertainty in the outcomes of such studies. This work presents the results of near-field measurement of 12 types of fine particle emission sources to develop local-region source profiles in the Monterrey Metropolitan Area. The source profiles include a chemical characterization of trace elements and carbonaceous fraction. A statistical analysis based on the Pearson distance and similarity identity distance was conducted to ensure the uniqueness of each source profile. Overall, the most dominant species in the profiles were organic and elemental carbon, and elemental sulfur, whereas the least abundant were transition metals. The meat-cooking operations profiles exhibited the highest organic carbon to elemental carbon ratios, which were 7-40 times higher than those for biomass burning and vehicle exhausts profiles. The urban construction profile was dominated by crustal elements, while the suburban area profile exhibited an internal mixing with anthropogenic compounds. The source profiles in this study were distinguishable, as determined by preliminary tests for each pair of chemical source profiles. These profiles could be used to implement receptor models in urban sites with similar characteristics.
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Parveen, Abidah, John S. Adams, Vijayasankar Raman, Jane M. Budel, Jianping Zhao, Ganesh N. M. Babu, Zulfiqar Ali et Ikhlas A. Khan. « Comparative Morpho-Anatomical and HPTLC Profiling of Tinospora Species and Dietary Supplements ». Planta Medica 86, no 07 (13 mars 2020) : 470–81. http://dx.doi.org/10.1055/a-1120-3711.

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AbstractOverlapping geographical occurrence, history of traditional use, confusion in species identification, and morphological resemblances among various species are some considerations that necessitate the importance of qualitative analysis for efficient quality control and safer botanical products. This paper provides detailed morpho-anatomies of the leaves and stems of Tinospora cordifolia, Tinospora crispa, and Tinospora sinensis, and stems of Tinospora baenzigeri. Microscopy studies of the selected Tinospora species revealed key diagnostic features that can help distinguish the closely related species of Tinospora as well as to detect any adulteration or substitution in the raw materials. HPTLC profiles of the authenticated plant materials, as well as commercial products claiming to contain Tinospora, were compared to distinguish T. crispa from other closely related species and to establish an efficient method to assess the identity and quality of the products using qualified chemical markers. HPTLC chromatograms of both plant samples and dietary supplements were compared with six reference marker compounds. The analysis revealed that borapetoside B and C were useful to identify T. crispa while tinosineside A was found to be characteristic to authenticate the T. sinensis products.
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Sič, B., L. El Amraoui, V. Marécal, B. Josse, J. Arteta, J. Guth, M. Joly et P. Hamer. « Modelling of primary aerosols in the chemical transport model MOCAGE : development and evaluation of aerosol physical parameterizations ». Geoscientific Model Development Discussions 7, no 2 (29 avril 2014) : 2745–96. http://dx.doi.org/10.5194/gmdd-7-2745-2014.

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Abstract. This paper deals with recent improvements to the chemical transport model of Météo-France MOCAGE that consists of updates to different aerosol parameterizations. MOCAGE only contains primary aerosol species. We introduced important changes to the aerosol parameterization concerning emissions, wet deposition and sedimentation. For the emissions, size distribution and wind calculations are modified for desert dust aerosols, and a surface sea temperature dependant source function is introduced for sea salt aerosols. Wet deposition is modified toward a more physically realistic representation by introducing re-evaporation of falling rain and snowfall scavenging, and by changing in-cloud scavenging scheme along with calculations of precipitation cloud cover and rain properties. The sedimentation scheme update includes changes regarding the stability and viscosity calculations. Independent data from satellites (MODIS, SEVIRI), the ground (AERONET), and a model inter-comparison project (AeroCom) is compared with MOCAGE simulations and showed that the introduced changes brought a significant improvement on aerosol representation, properties and global distribution. Emitted quantities of desert dust and sea salt, as well their lifetimes, moved closer towards values of AeroCom estimates and the multi-model average. When comparing the model simulations with MODIS aerosol optical depth (AOD) observations over the oceans, the updated model configuration shows a decrease in the bias (from 0.032 to 0.002) and a better correlation (from 0.062 to 0.322) in terms of the geographical distribution and the temporal variability. The updates corrected a strong positive bias in the sea salt representation at high latitudes (from 0.153 to 0.026), and a negative bias in the desert dust representation in the African dust outflow region (from −0.179 to −0.051). The updates in sedimentation produced a modest difference; the bias with MODIS data from 0.002 in the updated configuration went to 0.003 in the updated configuration only without the sedimentation updates. Yet, the updates in the emissions and the wet deposition made a stronger impact on the results; the bias was 0.041 and 0.032 in updated configurations only without emission, and wet deposition updates, respectively. Also, the lifetime, the extent, and the strength of the episodic aerosol events are better reproduced in the updated configuration. The wet deposition processes and the differences between the various configurations that were tested greatly influence the representation of the episodic events. However, wet deposition is not a continuous process; it has a local and episodic signature and its representation depends strongly on the precipitation regime in the model.
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Trail, Dustin, Patrick Boehnke, Paul S. Savage, Ming-Chang Liu, Martha L. Miller et Ilya Bindeman. « Origin and significance of Si and O isotope heterogeneities in Phanerozoic, Archean, and Hadean zircon ». Proceedings of the National Academy of Sciences 115, no 41 (24 septembre 2018) : 10287–92. http://dx.doi.org/10.1073/pnas.1808335115.

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Hydrosphere interactions and alteration of the terrestrial crust likely played a critical role in shaping Earth’s surface, and in promoting prebiotic reactions leading to life, before 4.03 Ga (the Hadean Eon). The identity of aqueously altered material strongly depends on lithospheric cycling of abundant and water-soluble elements such as Si and O. However, direct constraints that define the character of Hadean sedimentary material are absent because samples from this earliest eon are limited to detrital zircons (ZrSiO4). Here we show that concurrent measurements of Si and O isotope ratios in Phanerozoic and detrital pre-3.0 Ga zircon constrain the composition of aqueously altered precursors incorporated into their source melts. Phanerozoic zircon from (S)edimentary-type rocks contain heterogeneous δ18O and δ30Si values consistent with assimilation of metapelitic material, distinct from the isotopic character of zircon from (I)gneous- and (A)norogenic-type rocks. The δ18O values of detrital Archean zircons are heterogeneous, although yield Si isotope compositions like mantle-derived zircon. Hadean crystals yield elevated δ18O values (vs. mantle zircon) and δ30Si values span almost the entire range observed for Phanerozoic samples. Coupled Si and O isotope data represent a constraint on Hadean weathering and sedimentary input into felsic melts including remelting of amphibolites possibly of basaltic origin, and fractional addition of chemical sediments, such as cherts and/or banded iron formations (BIFs) into source melts. That such sedimentary deposits were extensive enough to change the chemical signature of intracrustal melts suggests they may have been a suitable niche for (pre)biotic chemistry as early as 4.1 Ga.
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Enoch, Olalere Folasayo, Ab Aziz Shuaib et Khairul Azhar bin Mat Daud. « Potential of Clay Deposits in Kelantan for Ceramic Production : A Literature Analysis ». Advanced Materials Research 980 (juin 2014) : 74–78. http://dx.doi.org/10.4028/www.scientific.net/amr.980.74.

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Kelantan state, regarded as the cradle of Malay culture is not only known for her unique cultural heritage, but also a land blessed with both metallic and non-metallic minerals. These include enormous clay deposits discovered in six (6) districts with estimated total reserve of 29.4 million tonnes of ball clay and 51.5 million tonnes of mottled clay. Hence, this paper investigates the physiochemical and mineralogical properties of the clay deposits. This was achieved by reviewing existing literatures and reports at the Mineral and Geoscience Department, Malaysia. The properties investigated were green and fired clay colour, plasticity, green strength, dry and fired shrinkage, porosity, chemical and mineral composition. The properties of the clay revealed that they have geographical IP potential; particularly, the predominantly off-white fired colour of the ball clay at temperature range of 900-11000C can secure an identity for Kelantan ceramics in the local, national or international market. Based on these properties, the ball clay is applicable for table ware, earthenware and local tile production while the mottled clay has a potential use for vitrified clay pipe, local tile and brick production.
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Sič, B., L. El Amraoui, V. Marécal, B. Josse, J. Arteta, J. Guth, M. Joly et P. D. Hamer. « Modelling of primary aerosols in the chemical transport model MOCAGE : development and evaluation of aerosol physical parameterizations ». Geoscientific Model Development 8, no 2 (23 février 2015) : 381–408. http://dx.doi.org/10.5194/gmd-8-381-2015.

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Abstract. This paper deals with recent improvements to the global chemical transport model of Météo-France MOCAGE (Modèle de Chimie Atmosphérique à Grande Echelle) that consists of updates to different aerosol parameterizations. MOCAGE only contains primary aerosol species: desert dust, sea salt, black carbon, organic carbon, and also volcanic ash in the case of large volcanic eruptions. We introduced important changes to the aerosol parameterization concerning emissions, wet deposition and sedimentation. For the emissions, size distribution and wind calculations are modified for desert dust aerosols, and a surface sea temperature dependant source function is introduced for sea salt aerosols. Wet deposition is modified toward a more physically realistic representation by introducing re-evaporation of falling rain and snowfall scavenging and by changing the in-cloud scavenging scheme along with calculations of precipitation cloud cover and rain properties. The sedimentation scheme update includes changes regarding the stability and viscosity calculations. Independent data from satellites (MODIS, SEVIRI), the ground (AERONET, EMEP), and a model inter-comparison project (AeroCom) are compared with MOCAGE simulations and show that the introduced changes brought a significant improvement on aerosol representation, properties and global distribution. Emitted quantities of desert dust and sea salt, as well their lifetimes, moved closer towards values of AeroCom estimates and the multi-model average. When comparing the model simulations with MODIS aerosol optical depth (AOD) observations over the oceans, the updated model configuration shows a decrease in the modified normalized mean bias (MNMB; from 0.42 to 0.10) and a better correlation (from 0.06 to 0.32) in terms of the geographical distribution and the temporal variability. The updates corrected a strong positive MNMB in the sea salt representation at high latitudes (from 0.65 to 0.16), and a negative MNMB in the desert dust representation in the African dust outflow region (from −1.01 to −0.22). The updates in sedimentation produced a modest difference; the MNMB with MODIS data from 0.10 in the updated configuration went to 0.11 in the updated configuration only without the sedimentation updates. Yet, the updates in the emissions and the wet deposition made a stronger impact on the results; the MNMB was 0.27 and 0.21 in updated configurations only without emission, and only without wet deposition updates, respectively. Also, the lifetime, the extent, and the strength of the episodic aerosol events are better reproduced in the updated configuration. The wet deposition processes and the differences between the various configurations that were tested greatly influence the representation of the episodic events. However, wet deposition is not a continuous process; it has a local and episodic signature and its representation depends strongly on the precipitation regime in the model.
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Ovchinnikov, Andrey Yurievich, et Konstantin Mikhailovich Andreev. « Soil-archaeological characteristic of the archaeological settlement Kalmykovka I in the Samara Volga Region ». Samara Journal of Science 7, no 3 (15 août 2018) : 208–14. http://dx.doi.org/10.17816/snv201873212.

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The paper publishes the results of soil research on the archaeological site - the settlement of the Neolithic and Bronze age Kalmykovka I located in the Krasnoyarsk district of the Samara Region. The paper briefly describes the archaeological site. Its cultural identity and the absolute age of the found artifacts are indicated. The morphological studies and analysis of the physical and the chemical properties of the modern soils, soil-forming rocks and cultural archaeological layers were carried out at the key site The taxonomic difference in soils was identified, related to the anthropogenic transformation of the soil in the middle and late Holocene. The physical properties of soils, and in particular, the granulometric composition, acquire lighter fractions in the direction from the watershed to the river terraces and slopes. Such pattern is recorded on other archaeological sites in the Middle Volga Region. The meandering of riverbed and the change in the level of rivers at different time intervals of the Holocene leaded to a change in the granulometric composition of the territory of the riverbed and river terrace. The preliminary results showed that an ancient man accounted for: a geographical location, a landscape exposure, the riverbed and the river level while arranging the settlement Kalmykovka I in different periods of the Holocene. The change in the paleogeographic situation on the given territory from the Middle Holocene to the Late one apparently influenced the river level content of the Sok River and its riverbed, which forced the generations of people to move the settlement deep into the watershed surface.
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Carretta, Eugenio. « Empirical estimates of the Na–O anti-correlation in 95 Galactic globular clusters ». Astronomy & ; Astrophysics 624 (avril 2019) : A24. http://dx.doi.org/10.1051/0004-6361/201935110.

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Large star-to-star abundance variations are direct evidence of multiple stellar populations in Galactic globular clusters (GCs). The main and most widespread chemical signature is the anti-correlation of the stellar Na and O abundances. The interquartile range (IQR) of the [O/Na] ratio is well suited to quantifying the extent of the anti-correlation and to probe its links to global cluster parameters. However, since it is quite time consuming to obtain precise abundances from spectroscopy for large samples of stars in GCs, here we show empirical calibrations of IQR[O/Na] based on the O, Na abundances homogeneously derived from more than 2000 red giants in 22 GCs in our FLAMES survey. We find a statistically robust bivariate correlation of IQR as a function of the total luminosity (a proxy for mass) and cluster concentration c. Calibrated and observed values lie along the identity line when a term accounting for the horizontal branch (HB) morphology is added to the calibration, from which we obtained empirical values for 95 GCs. Spreads in proton-capture elements O and Na are found for all GCs in the luminosity range from MV = −3.76 to MV = −9.98. This calibration reproduces in a self-consistent picture the link of abundance variations in light elements with the He enhancements and its effect on the stellar distribution on the HB. We show that the spreads in light elements seem already to be dependent on the initial GC masses. The dependence of IQR on structural parameters stems from the well known correlation between c and MV, which is likely to be of primordial origin. Empirical estimates can be used to extend our investigation of multiple stellar populations to GCs in external galaxies, up to M 31, where even integrated light spectroscopy may currently provide only a hint of such a phenomenon.
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Islam, Nurul, Rupjyoti Bharali, Sailen Talukdar, Syed Akram Hussain, Afzal Hoque Akand et Hridip Kumar Sarma. « Occurrence and Distribution of Cryptococcus Species in Environmental Sources from Lower Assam Belt of India ». Journal of Pure and Applied Microbiology 14, no 4 (30 décembre 2020) : 2781–800. http://dx.doi.org/10.22207/jpam.14.4.54.

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Cryptococcus is a non-motile, gram positive, non-fermenting Basidiomycetous encapsulated yeast like fungus that causes respiratory, neurological and other systemic diseases in both humans and animals. Present study delineates the possible distribution of Cryptococcus species in pigeon droppings, excreta of other avian species, eucalyptus tree and contaminated soil specimens collected from different geographical co-ordinates of six geographical regions of the lower Brahmaputra Valley of Assam, India. The fungi were isolated through conventional methods of Sabouraud Dextrose Agar (SDA) and Bird Seed Agar (BSA) media and identified through negative staining of capsule as well as performing classical bio-chemical tests. Identity of the isolates was further confirmed through sequence analysis of ITS-1 and ITS-4 region of the 18S rDNA. Two pathogenic species of Cryptococcus were isolated from 67 (15.40%) of the 435 specimens. Of these positive isolates 41 (9.43%) belonged to Naganishia albida (Cryptococcus albidus) while 26 (5.98%) represented Papiliotrema laurentii (Cryptococcus laurentii). Both the species were recovered from 58 (18.35%) dry and 9 (7.56%) moist specimens. The percentage of prevalence of Naganishia albida in dry and moist specimens were 35 (11.07%) and 6 (5.04%) respectively. Contrary to this, the percentage of prevalence of Papiliotrema laurentii in dry and moist were 23 (7.28%) and 3 (2.52%) respectively. The findings indicate that Cryptococcus species have established a better ecological sustenance in dry specimens than moist. The findings of the investigation demonstrated that the prevalence of Cryptococcus albidus in attics, dovecotes / houses of pigeon fanciers, contaminated soil, eucalyptus tree and droppings of other birds were 11(12.36%) out of 89, 23(14.11%) of 163,2(3.23%) of 62,4(7.84%) of 51 and only 1(1.43%) out of 7 specimens respectively. The recovery of Papiliotrema laurentii in the above specimens were 3(3.37%), 20(12.27%), 1(1.61%), 1(1.96%) and 1(1.42%) respectively. The findings revealed that the prevalence of Naganishia albida is more than that of Papiliotrema laurentii in natural substrates. The notorious pathogenic fungi, Cryptococcus neoformans could not be isolated, indicative of the fact that the region selected for the study is not environmentally favorable for growth and sustenance of the species. Findings of the study clearly demonstrate the ecological and epidemiological significance of the non-neoformans species of the genus cryptococcus that needs further comprehensive studies to access the prevalence of the genus from public health point of view.
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Boyarskikh, Irina Georgiyevna. « VARIABILITY OF THE INDIVIDUAL-GROUP COMPOSITION OF POLYPHENOLS OF THE FRUITS AND LEAVES OF BLUE HONEYSUCKLE SAMPLES OF DIFFERENT ECOLOGICAL AND GEOGRAPHICAL ORIGIN IN THE OB FOREST-STEPPE ». chemistry of plant raw material, no 2 (10 juin 2021) : 145–54. http://dx.doi.org/10.14258/jcprm.2021027651.

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The aim of the study was to compare the variability of the composition, chemical identity and content of biologically active phenolic compounds in the fruits and leaves of the blue honeysuckle (Lonicera subsection Caeruleae) plants of different environmental and geographic provenances, sampled from the introduction plantation station in the forest steppe zone near the Ob River (Novosibirsk, Russia). In extracts from the leaves 25 individual compounds representing various polyphenolic classes were identified using HPLC-MS technique; seven of the compounds were identified as hydroxycinnamic acids, five compounds were flavonols, and eight compounds represented flavones. The maximal number of individual compounds was present in samples of the Altai subspecies of the tetraploid species L. caerulea subsp. altaica, whereas the minimal number was detected in samples of L. boczkarnikowae, a diploid species from the Russian Far East (Primorsky region). The lowest total polyphenolics content (6,260 mg/100 g of air-dry phytomass) was found in samples of L. caeruleae subsp. pallasii, whereas the content in samples from other blue honeysuckle subspecies ranged within 11.620-14.030 mg/100 g of air-dry phytomass. High content of flavones in extracts from leaves, always exceeding the flavonol content, was found to be a characteristic feature of L. caerulea subsp. altaica. Among L. сaerulea subspecies, L. сaerulea subsp. pallasii was shown to have the largest ratio of flavonols to flavones. L. boczkarnikowae also had high content of flavonols, significantly exceeding the flavones content in the plants organs. The main component of anthocyanins was cyanidin-3-glucoside, accounting for up to 91%. The fruits of L. caerulea subsp. altaica, L. сaerulea subsp. venulosa and L. boczkarnikowae had the highest anthocyanin content, ranging 2.950–3.200 mg/100 g air-dry phytomass, whereas the fruits of L. сaerulea subsp. pallasii had the lowest one (1,573 mg/100g). Extracts from the leaves were found to have significantly higher polyphenolics content as compared to the ones from the fruits; thus the leaves can be recommended as a prospective medicinal source.
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Geană, Elisabeta-Irina, Corina Teodora Ciucure, Constantin Apetrei et Victoria Artem. « Application of Spectroscopic UV-Vis and FT-IR Screening Techniques Coupled with Multivariate Statistical Analysis for Red Wine Authentication : Varietal and Vintage Year Discrimination ». Molecules 24, no 22 (17 novembre 2019) : 4166. http://dx.doi.org/10.3390/molecules24224166.

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One of the most important issues in the wine sector and prevention of adulterations of wines are discrimination of grape varieties, geographical origin of wine, and year of vintage. In this experimental research study, UV-Vis and FT-IR spectroscopic screening analytical approaches together with chemometric pattern recognition techniques were applied and compared in addressing two wine authentication problems: discrimination of (i) varietal and (ii) year of vintage of red wines produced in the same oenological region. UV-Vis and FT-IR spectra of red wines were registered for all the samples and the principal features related to chemical composition of the samples were identified. Furthermore, for the discrimination and classification of red wines a multivariate data analysis was developed. Spectral UV-Vis and FT-IR data were reduced to a small number of principal components (PCs) using principal component analysis (PCA) and then partial least squares discriminant analysis (PLS-DA) and linear discriminant analysis (LDA) were performed in order to develop qualitative classification and regression models. The first three PCs used to build the models explained 89% of the total variance in the case of UV-Vis data and 98% of the total variance for FR-IR data. PLS-DA results show that acceptable linear regression fits were observed for the varietal classification of wines based on FT-IR data. According to the obtained LDA classification rates, it can be affirmed that UV-Vis spectroscopy works better than FT-IR spectroscopy for the discrimination of red wines according to the grape variety, while classification of wines according to year of vintage was better for the LDA based FT-IR data model. A clear discrimination of aged wines (over six years) was observed. The proposed methodologies can be used as accessible tools for the wine identity assurance without the need for costly and laborious chemical analysis, which makes them more accessible to many laboratories.
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Holden, Claire Anne, John Paul Bailey, Jane Elizabeth Taylor, Frank Martin, Paul Beckett et Martin McAinsh. « Know your enemy : Application of ATR-FTIR spectroscopy to invasive species control ». PLOS ONE 17, no 1 (7 janvier 2022) : e0261742. http://dx.doi.org/10.1371/journal.pone.0261742.

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Extreme weather and globalisation leave our climate vulnerable to invasion by alien species, which have negative impacts on the economy, biodiversity, and ecosystem services. Rapid and accurate identification is key to the control of invasive alien species. However, visually similar species hinder conservation efforts, for example hybrids within the Japanese Knotweed complex. We applied the novel method of ATR-FTIR spectroscopy combined with chemometrics (mathematics applied to chemical data) to historic herbarium samples, taking 1580 spectra in total. Samples included five species from within the interbreeding Japanese Knotweed complex (including three varieties of Japanese Knotweed), six hybrids and five species from the wider Polygonaceae family. Spectral data from herbarium specimens were analysed with several chemometric techniques: support vector machines (SVM) for differentiation between plant types, supported by ploidy levels; principal component analysis loadings and spectral biomarkers to explore differences between the highly invasive Reynoutria japonica var. japonica and its non-invasive counterpart Reynoutria japonica var. compacta; hierarchical cluster analysis (HCA) to investigate the relationship between plants within the Polygonaceae family, of the Fallopia, Reynoutria, Rumex and Fagopyrum genera. ATR-FTIR spectroscopy coupled with SVM successfully differentiated between plant type, leaf surface and geographical location, even in herbarium samples of varying age. Differences between Reynoutria japonica var. japonica and Reynoutria japonica var. compacta included the presence of two polysaccharides, glucomannan and xyloglucan, at higher concentrations in Reynoutria japonica var. japonica than Reynoutria japonica var. compacta. HCA analysis indicated that potential genetic linkages are sometimes masked by environmental factors; an effect that can either be reduced or encouraged by altering the input parameters. Entering the absorbance values for key wavenumbers, previously highlighted by principal component analysis loadings, favours linkages in the resultant HCA dendrogram corresponding to expected genetic relationships, whilst environmental associations are encouraged using the spectral fingerprint region. The ability to distinguish between closely related interbreeding species and hybrids, based on their spectral signature, raises the possibility of using this approach for determining the origin of Japanese knotweed infestations in legal cases where the clonal nature of plants currently makes this difficult and for the targeted control of species and hybrids. These techniques also provide a new method for supporting biogeographical studies.
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Mishra, Sonali, Nupur Srivastava, Velusamy Sundaresan et Karuna Shanker. « Amruthapala (Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter) : A Comprehensive Review on Diversity, Therapeutic Uses, and Valorization of Bioactive Constituents ». Current Pharmaceutical Biotechnology 20, no 5 (18 juin 2019) : 376–89. http://dx.doi.org/10.2174/1389201020666190318115504.

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Background: Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter is used primarily for nutrition besides its therapeutic values. Traditional preparations/formulations from its tuber are used as a vitalizer and blood purifier drink. The folklore medicinal uses cover inflammation, cough, wound healing, antipyretic, and digestive system management. A comprehensive review of the current understanding of the plant is required due to emerging concerns over its safety and efficacy. Objective: The systematic collection of the authentic information from different sources with the critical discussion is summarised in order to address various issues related to botanical identity, therapeutic medicine, nutritional usage, phytochemical, and pharmacological potentials of the D. arayalpathra. Current use of traditional systems of medicine can be used to expand future research opportunities. Materials and Methods: Available scripted information was collected manually, from peered review research papers and international databases viz. Science Direct, Google Scholar, SciFinder, Scopus, etc. The unpublished resources which were not available in database were collected through the classical books of ‘Ayurveda’ and ‘Siddha’ published in regional languages. The information from books, Ph.D. and MSc dissertations, conference papers and government reports were also collected. We thoroughly screened the scripted information of classical books, titles, abstracts, reports, and full-texts of the journals to establish the reliability of the content. Results: Tuber bearing vanilla like signature flavor is due to the presence of 2-hydroxy-4-methoxybenzaldehyde (HMB). Among five other species, Decalepis arayalpathra (DA) has come under the ‘critically endangered’ category, due to over-exploitation for traditional, therapeutic and cool drink use. The experimental studies proved that it possesses gastro-protective, anti-tumor, and antiinflammatory activities. Some efforts were also made to develop better therapeutics by logical modifications in 2-Hydroxy-4-methoxy-benzaldehyde, which is a major secondary metabolite of D. arayalpathra. ‘Amruthapala’ offers the enormous opportunity to develop herbal drink with health benefits like gastro-protective, anti-oxidant and anti-inflammatory actions. Results: The plant has the potential to generate the investigational new lead (IND) based on its major secondary metabolite i.e. 2-Hydroxy-4-methoxy-benzaldehyde. The present mini-review summarizes the current knowledge on Decalepis arayalpathra, covering its phytochemical diversity, biological potentials, strategies for its conservation, and intellectual property rights (IPR) status. Chemical Compounds: 2-hydroxy-4-methoxybenzaldehyde (Pubchem CID: 69600), α-amyrin acetate (Pubchem CID: 293754), Magnificol (Pubchem CID: 44575983), β-sitosterol (Pubchem CID: 222284), 3-hydroxy-p-anisaldehyde (Pubchem CID: 12127), Naringenin (Pubchem CID: 932), Kaempferol (Pubchem CID: 5280863), Aromadendrin (Pubchem CID: 122850), 3-methoxy-1,2-cyclopentanedione (Pubchem CID: 61209), p-anisaldehyde (Pubchem CID: 31244), Menthyl acetate (Pubchem CID: 27867), Benzaldehyde (Pubchem CID: 240), p-cymene (Pubchem CID: 7463), Salicylaldehyde (Pubchem CID: 6998), 10-epi-γ-eudesmol (Pubchem CID: 6430754), α -amyrin (Pubchem CID: 225688), 3-hydroxy-4-methoxy benzaldehyde (Pubchem CID: 12127).
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Garde, Adam A., et Feiko Kalsbeek. « Colophon, contents, preface ». Geological Survey of Denmark and Greenland (GEUS) Bulletin 11 (5 décembre 2006) : 1–7. http://dx.doi.org/10.34194/geusb.v11.4913.

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The present volume marks the completion of a large research project by the Geological Survey of Denmark and Greenland (GEUS), focused on the northern part of the Palaeoproterozoic Nagssugtoqidian orogen of central West Greenland, and carried out by a team of Danish and international participants. The project comprised geological mapping as well as structural, geochronological, geochemical and economic geological studies. This volume contains reports on both Archaean and Palaeoproterozoic geology as well as a study of neotectonic brittle structures. The field work was carried out in 2000-2003 in the region between Nordre Strømfjord and Jakobshavn Isfjord (see e.g. van Gool & Piazolo 2006, this volume, fig. 1). The project had two immediate purposes, namely to establish an overview of the mineral resource potential of supracrustal rocks in the region between 66° and 70°15'N, and produce four new geological sheets in the Survey's 1:100 000 map series. The first collection of papers about the Nagssugtoqidian orogen, published by the Geological Survey of Greenland (GGU, now part of GEUS), dates back to 1979 (Korstgård 1979). The investigations in this period were mainly based on field descriptions and structural analysis of coastal areas in the southern and central parts of the orogen, combined with limited petrographical, palaeomagnetic and geochronological studies; the results also comprised the first 1:100 000 geological map from within the Nagssugtoqidian orogen (Olesen 1984). The Proterozoic age of the orogen had been established, but it was believed that most, if not all of the quartzofeldspathic basement gneisses were of Archaean origin. Subsequent work in the Nagssugtoqidian orogen by GGU in the 1980s showed that besides Archaean orthogneisses and supracrustal rocks, the central part of the orogen also comprises the root zone of a Palaeoproterozoic magmatic arc and associated panels of Palaeoproterozoic volcanic and metasedimentary rocks (Kalsbeek et al. 1987). These results were confirmed during further investigations by the Danish Lithosphere Centre (DLC) in 1994-1999, and the plate-tectonic collisional history of the southern and central Nagssugtoqidian orogen was described in detail (van Gool et al. 2002). However, these studies added little to previous knowledge of the northern parts of the orogen in the Kangaatsiaq-Aasiaat-Qasigiannguit region, knowledge that was largely based on coastal reconnaissance by Henderson (1969) at the time when the entire orogen was still believed to consist of Archaean rocks. Another project preceding the present work was carried out by GGU in 1988-1991 immediately north of the Nagssugtoqidian orogen, in the southernmost part of the likewise Palaeoproterozoic Rinkian fold belt (Disko Bugt project, Kalsbeek 1999). It was shown that also the latter region comprises Palaeoproterozoic (meta)sedimentary rocks, and that most of the Archaean basement is strongly overprinted by Palaeoproterozoic structures that were formed during overall W- or NW-directed lateral tectonic transport. Although these structures might be related to similar structures in the Nagssugtoqidian orogen, the relationship between the Nagssugtoqidian orogen and the Rinkian fold belt remained speculative. The only previous economic geological study of regional extent in central West Greenland was an airborne reconnaissance study supplemented by local field work, which was carried out in the early 1960s by Kryolitselskabet Øresund A/S. This work resulted in the discovery of a massive sulphide deposit at Naternaq (Lersletten), which was studied again in some detail in 2001 by the Survey (Østergaard et al. 2002) but not reported on in the present volume. The present volume comprises 12 papers with topics ranging geochronologically from mid-Archaean to Palaeogene, and geographically from the southern Nagssugtoqidian foreland to the central part of the Rinkian fold belt. Many of the papers deal with the northern part of the Nagssugtoqidian orogen and are related to the recent field work in that region, while a few contributions are rooted in DLC- or other projects. The papers have been arranged in approximate chronological order and are grouped in terms of their main subjects. The two first papers, by Hollis et al. and Moyen & Watt, deal with Archaean supra- and infracrustal rocks in the northern Nagssugtoqidian orogen: their origin, ages, and structural and metamorphic evolution. These papers provide insight into the age and origin of the continental crustal orthogneisses and granites that underlie most of the region, and discuss the relationships between the supracrustal and plutonic components, using zircon U-Pb age determinations and major and trace element geochemical characteristics. Also the question of Palaeoproterozoic tectonic overprint is discussed, with the conclusion from both study areas that most of the observed structures are Archaean. The third paper with focus on Archaean geology, by Stendal et al., describes a small gold prospect at Attu likewise in the northern Nagssugtoqidian orogen, and discusses the age of the prospect and its host rocks using Pb-Pb geochronology of magnetite. It is concluded that the host rocks at Attu may be as old as 3162 ± 43 Ma, and that the gold prospect itself is around 2650 Ma in age. The fourth paper, by Mayborn & Lesher, is a thorough review of the Kangâmiut dyke swarm in the southern Nagssugtoqidian orogen and its foreland. It includes new whole-rock and mineral chemical data, and a list of sampling sites and corresponding field data. The emplacement mechanism and depth of the dyke swarm are discussed in detail, and it is concluded that the dykes were emplaced during the initial rifting prior to the Nagssugtoqidian collision and that they are unrelated to subduction processes (contrary to the belief by some previous authors). The next three papers provide geochronological constraints on the ages of supra- and infracrustal rocks and the deformation and metamorphism in the northern Nagssugtoqidian orogen, and on late orogenic uplift in the central Rinkian fold belt. In the first of these papers Thrane & Connelly employ zircon U-Pb age determinations (mainly using the laser ICP-MS method), and for the first time provide unequivocal documentation that the Naternaq supracrustal belt is of Palaeoproterozoic age. Other zircon age data from a synkinematic granite southeast of Kangaatsiaq show that the large fold structures in this region are of Archaean age. The subsequent paper by Stendal et al. presents Pb-Pb ages and isotopic signatures of magnetite in amphibolites; the obtained ages are younger than 1800 Ma and are related to cooling of the orogen. Stepwise leaching Pb-Pb ages of monazite and allanite in pegmatites fall in the range of 1750-1800 Ma, and are interpreted to date the emplacement of these rocks. The third paper in this group, by Sidgren et al., deals with new 40Ar/39Ar ages of around 1790 Ma (hornblende) and 1680 Ma (muscovite) from Archaean and Palaeoproterozoic rocks in the central Rinkian fold belt, which are interpreted as orogenic cooling ages. The hornblende ages are significantly older than such hornblende ages previously obtained from the central and northern Nagssugtoqidian orogen, pointing to different uplift histories in the two regions. This may in turn suggest that the Rinkian continental collision preceded that in the Nagssugtoqidian orogen. Four of the remaining five papers deal with the Nagssugtoqidian structural evolution. In the first of these, van Gool & Piazolo present a new method of structural analysis, where a geographical information system (GIS) is used as a framework for visualisation and analysis of large amounts of structural data. The paper graphically presents an overview of thousands of data points within an area of approximately 160 × 180 km in the central and northern parts of the Nagssugtoqidian orogen. This interesting data set points directly towards the two next papers, where crustal-scale structures in the same region and their origin are discussed: Sørensen et al. address the prominent Nordre Strømfjord shear zone just south of this block, and describes the structural and metasomatic transition into the shear zone by means of aeromagnetic and lithological map patterns and geochemical data. Another paper, by Mazur et al., addresses a prominent break in the structural pattern within the Kangaatsiaq-Aasiaat area, where the southern part acted as a rigid block during the Nagssugtoqidian orogeny and thus preserved its Archaean structure. The fourth paper in this group, by Korstgård et al., combines rock and aeromagnetic data to discuss the relationship between structure, metamorphic facies and total magnetic field intensity anomalies in the southern Nagssugtoqidian orogen. The authors show that static metamorphic boundaries are gradual, whereas boundaries along deformation zones are abrupt. The last paper, by Wilson et al., is a novel remote sensing and field geological analysis of onshore brittle structures related to the complex Ungava fault zone in the Davis Strait, which developed during the Cretaceous-Palaeogene opening of the Labrador Sea - Davis Strait - Baffin Bay seaway. The study area is located in the central Nagssugtoqidian orogen, and the authors carefully establish a distinction between old Nagssugtoqidian and younger structures in the basement rocks and identify five main sets of young lineaments. They conclude that the onshore fault patterns are predominantly of strike-slip nature, and that they reflect the stress fields that governed the opening of the seaway. Acknowledgements The editors are grateful to the 14 external reviewers, each of whom reviewed one or more of the individual papers, for their thorough and constructive work.
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Nesrine, Lenchi, Kebbouche Salima, Khelfaoui Mohamed Lamine, Laddada Belaid, BKhemili Souad, Gana Mohamed Lamine, Akmoussi Sihem et Ferioune Imène. « Phylogenetic characterization and screening of halophilic bacteria from Algerian salt lake for the production of biosurfactant and enzymes ». World Journal of Biology and Biotechnology 5, no 2 (15 août 2020) : 1. http://dx.doi.org/10.33865/wjb.005.02.0294.

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Environments containing significant concentration of NaCl such as salt lakes harbor extremophiles microorganisms which have a great biotechnology interest. To explore the diversity of Bacteria in Chott Tinsilt (Algeria), an isolation program was performed. Water samples were collected from the saltern during the pre-salt harvesting phase. This Chott is high in salt (22.47% (w/v). Seven halophiles Bacteria were selected for further characterization. The isolated strains were able to grow optimally in media with 10–25% (w/v) total salts. Molecular identification of the isolates was performed by sequencing the 16S rRNA gene. It showed that these cultured isolates included members belonging to the Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus genera with less than 98% of similarity with their closest phylogenetic relative. The halophilic bacterial isolates were also characterized for the production of biosurfactant and industrially important enzymes. Most isolates produced hydrolases and biosurfactants at high salt concentration. In fact, this is the first report on bacterial strains (A4 and B4) which were a good biosurfactant and coagulase producer at 20% and 25% ((w/v)) NaCl. In addition, the biosurfactant produced by the strain B4 at high salinity (25%) was also stable at high temperature (30-100°C) and high alkalinity (pH 11).Key word: Salt Lake, Bacteria, biosurfactant, Chott, halophiles, hydrolases, 16S rRNAINTRODUCTIONSaline lakes cover approximately 10% of the Earth’s surface area. The microbial populations of many hypersaline environments have already been studied in different geographical regions such as Great Salt Lake (USA), Dead Sea (Israel), Wadi Natrun Lake (Egypt), Lake Magadi (Kenya), Soda Lake (Antarctica) and Big Soda Lake and Mono Lake (California). Hypersaline regions differ from each other in terms of geographical location, salt concentration and chemical composition, which determine the nature of inhabitant microorganisms (Gupta et al., 2015). Then low taxonomic diversity is common to all these saline environments (Oren et al., 1993). Halophiles are found in nearly all major microbial clades, including prokaryotic (Bacteria and Archaea) and eukaryotic forms (DasSarma and Arora, 2001). They are classified as slight halophiles when they grow optimally at 0.2–0.85 M (2–5%) NaCl, as moderate halophiles when they grow at 0.85–3.4 M (5–20%) NaCl, and as extreme halophiles when they grow at 3.4–5.1 M (20–30%) NaCl. Hyper saline environments are inhabited by extremely halophilic and halotolerant microorganisms such as Halobacillus sp, Halobacterium sp., Haloarcula sp., Salinibacter ruber , Haloferax sp and Bacillus spp. (Solomon and Viswalingam, 2013). There is a tremendous demand for halophilic bacteria due to their biotechnological importance as sources of halophilic enzymes. Enzymes derived from halophiles are endowed with unique structural features and catalytic power to sustain the metabolic and physiological processes under high salt conditions. Some of these enzymes have been reported to be active and stable under more than one extreme condition (Karan and Khare, 2010). Applications are being considered in a range of industries such as food processing, washing, biosynthetic processes and environmental bioremediation. Halophilic proteases are widely used in the detergent and food industries (DasSarma and Arora, 2001). However, esterases and lipases have also been useful in laundry detergents for the removal of oil stains and are widely used as biocatalysts because of their ability to produce pure compounds. Likewise, amylases are used industrially in the first step of the production of high fructose corn syrup (hydrolysis of corn starch). They are also used in the textile industry in the de-sizing process and added to laundry detergents. Furthermore, for the environmental applications, the use of halophiles for bioremediation and biodegradation of various materials from industrial effluents to soil contaminants and accidental spills are being widely explored. In addition to enzymes, halophilic / halotolerants microorganisms living in saline environments, offer another potential applications in various fields of biotechnology like the production of biosurfactant. Biosurfactants are amphiphilic compounds synthesized from plants and microorganisms. They reduce surface tension and interfacial tension between individual molecules at the surface and interface respectively (Akbari et al., 2018). Comparing to the chemical surfactant, biosurfactant are promising alternative molecules due to their low toxicity, high biodegradability, environmental capability, mild production conditions, lower critical micelle concentration, higher selectivity, availability of resources and ability to function in wide ranges of pH, temperature and salinity (Rocha et al., 1992). They are used in various industries which include pharmaceuticals, petroleum, food, detergents, cosmetics, paints, paper products and water treatment (Akbari et al., 2018). The search for biosurfactants in extremophiles is particularly promising since these biomolecules can adapt and be stable in the harsh environments in which they are to be applied in biotechnology.OBJECTIVESEastern Algeria features numerous ecosystems including hypersaline environments, which are an important source of salt for food. The microbial diversity in Chott Tinsilt, a shallow Salt Lake with more than 200g/L salt concentration and a superficies of 2.154 Ha, has never yet been studied. The purpose of this research was to chemically analyse water samples collected from the Chott, isolate novel extremely or moderate halophilic Bacteria, and examine their phenotypic and phylogenetic characteristics with a view to screening for biosurfactants and enzymes of industrial interest.MATERIALS AND METHODSStudy area: The area is at 5 km of the Commune of Souk-Naâmane and 17 km in the South of the town of Aïn-Melila. This area skirts the trunk road 3 serving Constantine and Batna and the railway Constantine-Biskra. It is part the administrative jurisdiction of the Wilaya of Oum El Bouaghi. The Chott belongs to the wetlands of the High Plains of Constantine with a depth varying rather regularly without never exceeding 0.5 meter. Its length extends on 4 km with a width of 2.5 km (figure 1).Water samples and physico-chemical analysis: In February 2013, water samples were collected from various places at the Chott Tinsilt using Global Positioning System (GPS) coordinates of 35°53’14” N lat. and 06°28’44”E long. Samples were collected randomly in sterile polythene bags and transported immediately to the laboratory for isolation of halophilic microorganisms. All samples were treated within 24 h after collection. Temperature, pH and salinity were measured in situ using a multi-parameter probe (Hanna Instruments, Smithfield, RI, USA). The analytical methods used in this study to measure ions concentration (Ca2+, Mg2+, Fe2+, Na+, K+, Cl−, HCO3−, SO42−) were based on 4500-S-2 F standard methods described elsewhere (Association et al., 1920).Isolation of halophilic bacteria from water sample: The media (M1) used in the present study contain (g/L): 2.0 g of KCl, 100.0/200.0 g of NaCl, 1.0 g of MgSO4.7HO2, 3.0 g of Sodium Citrate, 0.36 g of MnCl2, 10.0 g of yeast extract and 15.0 g agar. The pH was adjusted to 8.0. Different dilutions of water samples were added to the above medium and incubated at 30°C during 2–7 days or more depending on growth. Appearance and growth of halophilic bacteria were monitored regularly. The growth was diluted 10 times and plated on complete medium agar (g/L): glucose 10.0; peptone 5.0; yeast extract 5.0; KH2PO4 5.0; agar 30.0; and NaCl 100.0/200.0. Resultant colonies were purified by repeated streaking on complete media agar. The pure cultures were preserved in 20% glycerol vials and stored at −80°C for long-term preservation.Biochemical characterisation of halophilic bacterial isolates: Bacterial isolates were studied for Gram’s reaction, cell morphology and pigmentation. Enzymatic assays (catalase, oxidase, nitrate reductase and urease), and assays for fermentation of lactose and mannitol were done as described by Smibert (1994).Optimization of growth conditions: Temperature, pH, and salt concentration were optimized for the growth of halophilic bacterial isolates. These growth parameters were studied quantitatively by growing the bacterial isolates in M1 medium with shaking at 200 rpm and measuring the cell density at 600 nm after 8 days of incubation. To study the effect of NaCl on the growth, bacterial isolates were inoculated on M1 medium supplemented with different concentration of NaCl: 1%-35% (w/v). The effect of pH on the growth of halophilic bacterial strains was studied by inoculating isolates on above described growth media containing NaCl and adjusted to acidic pH of 5 and 6 by using 1N HCl and alkaline pH of 8, 9, 10, 11 and 12 using 5N NaOH. The effect of temperature was studied by culturing the bacterial isolates in M1 medium at different temperatures of incubation (4°C–55°C).Screening of halophilic bacteria for hydrolytic enzymes: Hydrolase producing bacteria among the isolates were screened by plate assay on starch, tributyrin, gelatin and DNA agar plates respectively for amylase, lipase, protease and DNAse activities. Amylolytic activity of the cultures was screened on starch nutrient agar plates containing g/L: starch 10.0; peptone 5.0; yeast extract 3.0; agar 30.0; NaCl 100.0/250.0. The pH was 7.0. After incubation at 30 ºC for 7 days, the zone of clearance was determined by flooding the plates with iodine solution. The potential amylase producers were selected based on ratio of zone of clearance diameter to colony diameter. Lipase activity of the cultures was screened on tributyrin nutrient agar plates containing 1% (v/v) of tributyrin. Isolates that showed clear zones of tributyrin hydrolysis were identified as lipase producing bacteria. Proteolytic activity of the isolates was similarly screened on gelatin nutrient agar plates containing 10.0 g/L of gelatin. The isolates showing zones of gelatin clearance upon treatment with acidic mercuric chloride were selected and designated as protease producing bacteria. The presence of DNAse activity on plates was determined on DNAse test agar (BBL) containing 10%-25% (w/v) total salt. After incubation for 7days, the plates were flooded with 1N HCl solution. Clear halos around the colonies indicated DNAse activity (Jeffries et al., 1957).Milk clotting activity (coagulase activity) of the isolates was also determined following the procedure described (Berridge, 1952). Skim milk powder was reconstituted in 10 mM aqueous CaCl2 (pH 6.5) to a final concentration of 0.12 kg/L. Enzyme extracts were added at a rate of 0.1 mL per mL of milk. The coagulation point was determined by manual rotating of the test tube periodically, at short time intervals, and checking for visible clot formation.Screening of halophilic bacteria for biosurfactant production. Oil spread Assay: The Petridis base was filled with 50 mL of distilled water. On the water surface, 20μL of diesel and 10μl of culture were added respectively. The culture was introduced at different spots on the diesel, which is coated on the water surface. The occurrence of a clear zone was an indicator of positive result (Morikawa et al., 2000). The diameter of the oil expelling circles was measured by slide caliber (with a degree of accuracy of 0.02 mm).Surface tension and emulsification index (E24): Isolates were cultivated at 30 °C for 7 days on the enrichment medium containing 10-25% NaCl and diesel oil as the sole carbon source. The medium was centrifuged (7000 rpm for 20 min) and the surface tension of the cell-free culture broth was measured with a TS90000 surface tensiometer (Nima, Coventry, England) as a qualitative indicator of biosurfactant production. The culture broth was collected with a Pasteur pipette to remove the non-emulsified hydrocarbons. The emulsifying capacity was evaluated by an emulsification index (E24). The E24 of culture samples was determined by adding 2 mL of diesel oil to the same amount of culture, mixed for 2 min with a vortex, and allowed to stand for 24 h. E24 index is defined as the percentage of height of emulsified layer (mm) divided by the total height of the liquid column (mm).Biosurfactant stability studies : After growth on diesel oil as sole source of carbone, cultures supernatant obtained after centrifugation at 6,000 rpm for 15 min were considered as the source of crude biosurfactant. Its stability was determined by subjecting the culture supernatant to various temperature ranges (30, 40, 50, 60, 70, 80 and 100 °C) for 30 min then cooled to room temperature. Similarly, the effect of different pH (2–11) on the activity of the biosurfactant was tested. The activity of the biosurfactant was investigated by measuring the emulsification index (El-Sersy, 2012).Molecular identification of potential strains. DNA extraction and PCR amplification of 16S rDNA: Total cellular DNA was extracted from strains and purified as described by Sambrook et al. (1989). DNA was purified using Geneclean® Turbo (Q-BIO gene, Carlsbad, CA, USA) before use as a template in polymerase chain reaction (PCR) amplification. For the 16S rDNA gene sequence, the purified DNA was amplified using a universal primer set, forward primer (27f; 5′-AGA GTT TGA TCM TGG CTC AG) and a reverse primer (1492r; 5′-TAC GGY TAC CTT GTT ACG ACT T) (Lane, 1991). Agarose gel electrophoresis confirmed the amplification product as a 1400-bp DNA fragment.16S rDNA sequencing and Phylogenic analysis: Amplicons generated using primer pair 27f-1492r was sequenced using an automatic sequencer system at Macrogene Company (Seoul, Korea). The sequences were compared with those of the NCBI BLAST GenBank nucleotide sequence databases. Phylogenetic trees were constructed by the neighbor-joining method using MEGA version 5.05 software (Tamura et al., 2011). Bootstrap resembling analysis for 1,000 replicates was performed to estimate the confidence of tree topologies.Nucleotide sequence accession numbers: The nucleotide sequences reported in this work have been deposited in the EMBL Nucleotide Sequence Database. The accession numbers are represented in table 5.Statistics: All experiments were conducted in triplicates. Results were evaluated for statistical significance using ANOVA.RESULTSPhysico-chemical parameters of the collected water samples: The physicochemical properties of the collected water samples are reported in table 1. At the time of sampling, the temperature was 10.6°C and pH 7.89. The salinity of the sample, as determined in situ, was 224.70 g/L (22,47% (w/v)). Chemical analysis of water sample indicated that Na +and Cl- were the most abundant ions (table 1). SO4-2 and Mg+2 was present in much smaller amounts compared to Na +and Cl- concentration. Low levels of calcium, potassium and bicarbonate were also detected, often at less than 1 g/L.Characterization of isolates. Morphological and biochemical characteristic feature of halophilic bacterial isolates: Among 52 strains isolated from water of Chott Tinsilt, seven distinct bacteria (A1, A2, A3, A4, B1, B4 and B5) were chosen for further characterization (table 2). The colour of the isolates varied from beige, pale yellow, yellowish and orange. The bacterial isolates A1, A2, A4, B1 and B5 were rod shaped and gram negative (except B5), whereas A3 and B4 were cocci and gram positive. All strains were oxidase and catalase positive except for B1. Nitrate reductase and urease activities were observed in all the bacterial isolates, except B4. All the bacterial isolates were negative for H2S formation. B5 was the only strain positive for mannitol fermentation (table 2).We isolated halophilic bacteria on growth medium with NaCl supplementation at pH 7 and temperature of 30°C. We studied the effect of NaCl, temperature and pH on the growth of bacterial isolates. All the isolates exhibited growth only in the presence of NaCl indicating that these strains are halophilic. The optimum growth of isolates A3 and B1 was observed in the presence of 10% NaCl, whereas it was 15% NaCl for A1, A2 and B5. A4 and B4 showed optimum growth in the presence of 20% and 25% NaCl respectively. A4, B4 and B5 strains can tolerate up to 35% NaCl.The isolate B1 showed growth in medium supplemented with 10% NaCl and pH range of 7–10. The optimum pH for the growth B1 was 9 and they did not show any detectable growth at or below pH 6 (table 2), which indicates the alkaliphilic nature of B1 isolate. The bacterial isolates A1, A2 and A4 exhibited growth in the range of pH 6–10, while A3 and B4 did not show any growth at pH greater than 8. The optimum pH for growth of all strains (except B1) was pH 7.0 (table 2). These results indicate that A1, A2, A3, A4, B4 and B5 are neutrophilic in nature. All the bacterial isolates exhibited optimal growth at 30°C and no detectable growth at 55°C. Also, detectable growth of isolates A1, A2 and A4 was observed at 4°C. However, none of the bacterial strains could grow below 4°C and above 50°C (table 2).Screening of the halophilic enzymes: To characterize the diversity of halophiles able to produce hydrolytic enzymes among the population of microorganisms inhabiting the hypersaline habitats of East Algeria (Chott Tinsilt), a screening was performed. As described in Materials and Methods, samples were plated on solid media containing 10%-25% (w/v) of total salts and different substrates for the detection of amylase, protease, lipase and DNAse activities. However, coagulase activity was determined in liquid medium using milk as substrate (figure 3). Distributions of hydrolytic activity among the isolates are summarized in table 4.From the seven bacterial isolates, four strains A1, A2, A4 and B5 showed combined hydrolytic activities. They were positive for gelatinase, lipase and coagulase. A3 strain showed gelatinase and lipase activities. DNAse activities were detected with A1, A4, B1 and B5 isolates. B4 presented lipase and coagulase activity. Surprisingly, no amylase activity was detected among all the isolates.Screening for biosurfactant producing isolates: Oil spread assay: The results showed that all the strains could produce notable (>4 cm diameter) oil expelling circles (ranging from 4.11 cm to 4.67 cm). The average diameter for strain B5 was 4.67 cm, significantly (P < 0.05) higher than for the other strains.Surface tension and emulsification index (E24): The assimilation of hydrocarbons as the sole sources of carbon by the isolate strains led to the production of biosurfactants indicated by the emulsification index and the lowering of the surface tension of cell-free supernatant. Based on rapid growth on media containing diesel oil as sole carbon source, the seven isolates were tested for biosurfactant production and emulsification activity. The obtained values of the surface tension measurements as well as the emulsification index (E24) are shown in table 3. The highest reduction of surface tension was achieved with B5 and A3 isolates with values of 25.3 mN m−1 and 28.1 mN m−1 respectively. The emulsifying capacity evaluated by the E24 emulsification index was highest in the culture of isolate B4 (78%), B5 (77%) and A3 (76%) as shown in table 3 and figure 2. These emulsions were stable even after 4 months. The bacteria with emulsification indices higher than 50 % and/or reduction in the surface tension (under 30 mN/m) have been defined as potential biosurfactant producers. Based on surface tension and the E24 index results, isolates B5, B4, A3 and A4 are the best candidates for biosurfactant production. It is important to note that, strains B4 and A4 produce biosurfactant in medium containing respectively 25% and 20% (w/v) NaCl.Stability of biosurfactant activities: The applicability of biosurfactants in several biotechnological fields depends on their stability at different environmental conditions (temperatures, pH and NaCl). For this study, the strain B4 appear very interesting (It can produce biosurfactant at 25 % NaCl) and was choosen for futher analysis for biosurfactant stability. The effects of temperature and pH on the biosurfactant production by the strain B4 are shown in figure 4.biosurfactant in medium containing respectively 25% and 20% (w/v) NaCl.Stability of biosurfactant activities: The applicability of biosurfactants in several biotechnological fields depends on their stability at different environmental conditions (temperatures, pH and NaCl). For this study, the strain B4 appear very interesting (It can produce biosurfactant at 25 % NaCl) and was chosen for further analysis for biosurfactant stability. The effects of temperature and pH on the biosurfactant production by the strain B4 are shown in figure 4. The biosurfactant produced by this strain was shown to be thermostable giving an E-24 Index value greater than 78% (figure 4A). Heating of the biosurfactant to 100 °C caused no significant effect on the biosurfactant performance. Therefore, the surface activity of the crude biosurfactant supernatant remained relatively stable to pH changes between pH 6 and 11. At pH 11, the value of E24 showed almost 76% activity, whereas below pH 6 the activity was decreased up to 40% (figure 4A). The decreases of the emulsification activity by decreasing the pH value from basic to an acidic region; may be due to partial precipitation of the biosurfactant. This result indicated that biosurfactant produced by strain B4 show higher stability at alkaline than in acidic conditions.Molecular identification and phylogenies of potential isolates: To identify halophilic bacterial isolates, the 16S rDNA gene was amplified using gene-specific primers. A PCR product of ≈ 1.3 kb was detected in all the seven isolates. The 16S rDNA amplicons of each bacterial isolate was sequenced on both strands using 27F and 1492R primers. The complete nucleotide sequence of 1336,1374, 1377,1313, 1305,1308 and 1273 bp sequences were obtained from A1, A2, A3, A4, B1, B4 and B5 isolates respectively, and subjected to BLAST analysis. The 16S rDNA sequence analysis showed that the isolated strains belong to the genera Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus as shown in table 5. The halophilic isolates A2 and A4 showed 97% similarity with the Halomonas variabilis strain GSP3 (accession no. AY505527) and the Halomonas sp. M59 (accession no. AM229319), respectively. As for A1, it showed 96% similarity with the Halomonas venusta strain GSP24 (accession no. AY553074). B1 and B4 showed for their part 96% similarity with the Salinivibrio costicola subsp. alcaliphilus strain 18AG DSM4743 (accession no. NR_042255) and the Planococcus citreus (accession no. JX122551), respectively. The bacterial isolate B5 showed 98% sequence similarity with the Halobacillus trueperi (accession no. HG931926), As for A3, it showed only 95% similarity with the Staphylococcus arlettae (accession no. KR047785). The 16S rDNA nucleotide sequences of all the seven halophilic bacterial strains have been submitted to the NCBI GenBank database under the accession number presented in table 5. The phylogenetic association of the isolates is shown in figure 5.DICUSSIONThe physicochemical properties of the collected water samples indicated that this water was relatively neutral (pH 7.89) similar to the Dead Sea and the Great Salt Lake (USA) and in contrast to the more basic lakes such as Lake Wadi Natrun (Egypt) (pH 11) and El Golea Salt Lake (Algeria) (pH 9). The salinity of the sample was 224.70 g/L (22,47% (w/v). This range of salinity (20-30%) for Chott Tinsilt is comparable to a number of well characterized hypersaline ecosystems including both natural and man-made habitats, such as the Great Salt Lake (USA) and solar salterns of Puerto Rico. Thus, Chott Tinsilt is a hypersaline environment, i.e. environments with salt concentrations well above that of seawater. Chemical analysis of water sample indicated that Na +and Cl- were the most abundant ions, as in most hypersaline ecosystems (with some exceptions such as the Dead Sea). These chemical water characteristics were consistent with the previously reported data in other hypersaline ecosystems (DasSarma and Arora, 2001; Oren, 2002; Hacěne et al., 2004). Among 52 strains isolated from this Chott, seven distinct bacteria (A1, A2, A3, A4, B1, B4 and B5) were chosen for phenotypique, genotypique and phylogenetique characterization.The 16S rDNA sequence analysis showed that the isolated strains belong to the genera Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus. Genera obtained in the present study are commonly occurring in various saline habitats across the globe. Staphylococci have the ability to grow in a wide range of salt concentrations (Graham and Wilkinson, 1992; Morikawa et al., 2009; Roohi et al., 2014). For example, in Pakistan, Staphylococcus strains were isolated from various salt samples during the study conducted by Roohi et al. (2014) and these results agreed with previous reports. Halomonas, halophilic and/or halotolerant Gram-negative bacteria are typically found in saline environments (Kim et al., 2013). The presence of Planococcus and Halobacillus has been reported in studies about hypersaline lakes; like La Sal del Rey (USA) (Phillips et al., 2012) and Great Salt Lake (Spring et al., 1996), respectively. The Salinivibrio costicola was a representative model for studies on osmoregulatory and other physiological mechanisms of moderately halophilic bacteria (Oren, 2006).However, it is interesting to note that all strains shared less than 98.7% identity (the usual species cut-off proposed by Yarza et al. (2014) with their closest phylogenetic relative, suggesting that they could be considered as new species. Phenotypic, genetic and phylogenetic analyses have been suggested for the complete identification of these strains. Theses bacterial strains were tested for the production of industrially important enzymes (Amylase, protease, lipase, DNAse and coagulase). These isolates are good candidates as sources of novel enzymes with biotechnological potential as they can be used in different industrial processes at high salt concentration (up to 25% NaCl for B4). Prominent amylase, lipase, protease and DNAase activities have been reported from different hypersaline environments across the globe; e.g., Spain (Sánchez‐Porro et al., 2003), Iran (Rohban et al., 2009), Tunisia (Baati et al., 2010) and India (Gupta et al., 2016). However, to the best of our knowledge, the coagulase activity has never been detected in extreme halophilic bacteria. Isolation and characterization of crude enzymes (especially coagulase) to investigate their properties and stability are in progress.The finding of novel enzymes with optimal activities at various ranges of salt concentrations is of great importance. Besides being intrinsically stable and active at high salt concentrations, halophilic and halotolerant enzymes offer great opportunities in biotechnological applications, such as environmental bioremediation (marine, oilfiel) and food processing. The bacterial isolates were also characterized for production of biosurfactants by oil-spread assay, measurement of surface tension and emulsification index (E24). There are few reports on biosurfactant producers in hypersaline environments and in recent years, there has been a greater increase in interest and importance in halophilic bacteria for biomolecules (Donio et al., 2013; Sarafin et al., 2014). Halophiles, which have a unique lipid composition, may have an important role to play as surface-active agents. The archae bacterial ether-linked phytanyl membrane lipid of the extremely halophilic bacteria has been shown to have surfactant properties (Post and Collins, 1982). Yakimov et al. (1995) reported the production of biosurfactant by a halotolerant Bacillus licheniformis strain BAS 50 which was able to produce a lipopeptide surfactant when cultured at salinities up to 13% NaCl. From solar salt, Halomonas sp. BS4 and Kocuria marina BS-15 were found to be able to produce biosurfactant when cultured at salinities of 8% and 10% NaCl respectively (Donio et al., 2013; Sarafin et al., 2014). In the present work, strains B4 and A4 produce biosurfactant in medium containing respectively 25% and 20% NaCl. To our knowledge, this is the first report on biosurfactant production by bacteria under such salt concentration. Biosurfactants have a wide variety of industrial and environmental applications (Akbari et al., 2018) but their applicability depends on their stability at different environmental conditions. The strain B4 which can produce biosurfactant at 25% NaCl showed good stability in alkaline pH and at a temperature range of 30°C-100°C. Due to the enormous utilization of biosurfactant in detergent manufacture the choice of alkaline biosurfactant is researched (Elazzazy et al., 2015). On the other hand, the interesting finding was the thermostability of the produced biosurfactant even after heat treatment (100°C for 30 min) which suggests the use of this biosurfactant in industries where heating is of a paramount importance (Khopade et al., 2012). To date, more attention has been focused on biosurfactant producing bacteria under extreme conditions for industrial and commercial usefulness. In fact, the biosurfactant produce by strain B4 have promising usefulness in pharmaceutical, cosmetics and food industries and for bioremediation in marine environment and Microbial enhanced oil recovery (MEOR) where the salinity, temperature and pH are high.CONCLUSIONThis is the first study on the culturable halophilic bacteria community inhabiting Chott Tinsilt in Eastern Algeria. Different genera of halotolerant bacteria with different phylogeneticaly characteristics have been isolated from this Chott. Culturing of bacteria and their molecular analysis provides an opportunity to have a wide range of cultured microorganisms from extreme habitats like hypersaline environments. Enzymes produced by halophilic bacteria show interesting properties like their ability to remain functional in extreme conditions, such as high temperatures, wide range of pH, and high salt concentrations. These enzymes have great economical potential in industrial, agricultural, chemical, pharmaceutical, and biotechnological applications. Thus, the halophiles isolated from Chott Tinsilt offer an important potential for application in microbial and enzyme biotechnology. In addition, these halo bacterial biosurfactants producers isolated from this Chott will help to develop more valuable eco-friendly products to the pharmacological and food industries and will be usefulness for bioremediation in marine environment and petroleum industry.ACKNOWLEDGMENTSOur thanks to Professor Abdelhamid Zoubir for proofreading the English composition of the present paper.CONFLICT OF INTERESTThe authors declare that they have no conflict of interest.Akbari, S., N. H. Abdurahman, R. M. Yunus, F. Fayaz and O. R. Alara, 2018. Biosurfactants—a new frontier for social and environmental safety: A mini review. Biotechnology research innovation, 2(1): 81-90.Association, A. P. H., A. W. W. Association, W. P. C. 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International journal scientific research paper publication sites, 4: 1-7.Spring, S., W. Ludwig, M. Marquez, A. Ventosa and K.-H. Schleifer, 1996. Halobacillus gen. Nov., with descriptions of Halobacillus litoralis sp. Nov. and Halobacillus trueperi sp. Nov., and transfer of Sporosarcina halophila to Halobacillus halophilus comb. Nov. International journal of systematic evolutionary microbiology, 46(2): 492-496.Tamura, K., D. Peterson, N. Peterson, G. Stecher, M. Nei and S. Kumar, 2011. Mega5: Molecular evolutionary genetics analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods. Molecular biology evolution, 28(10): 2731-2739.Yakimov, M. M., K. N. Timmis, V. Wray and H. L. Fredrickson, 1995. Characterization of a new lipopeptide surfactant produced by thermotolerant and halotolerant subsurface Bacillus licheniformis bas50. Applied and environmental microbiology, 61(5): 1706-1713.Yarza, P., P. Yilmaz, E. Pruesse, F. O. Glöckner, W. Ludwig, K.-H. 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Velho, Jesus. « New Trends in Analytical Chemistry for the Examination and Interpretation of Traces of Crimes ». Brazilian Journal of Analytical Chemistry, 21 janvier 2022, 13–14. http://dx.doi.org/10.30744/brjac.2179-3425.letter-javelho.

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Forensic sciences are generally described as the application of the scientific method to the analysis of traces in order to identify the authorship and materiality of a crime . Forensic scientists evaluate different types of materials, and the type of scientific method and techniques employed depend on the questions to be answered within a given context . Forensic chemistry is one of the most far-reaching areas within the forensic science field. With the increase in technology and the development of analytical techniques, chemistry has been used more and more to elucidate legal controversies. Therefore, knowledge in chemistry is indispensable to solve crimes. In this letter, the applications of analytical chemistry will be discussed within emerging forensic themes: the determination of the origin of seized drugs (chemical profiling), the investigation of document fraud, and the valuation analysis of pieces of art. Chemical profiling consists of a series of chemical analyses that provide the concentration of the components present in the seized drugs, present as major or minor components, or event those present only in trace levels. Using different analytical methods, complex chemical profiles are obtained for each drug sample analyzed, giving these samples a chemical “signature” based on the presence of impurities of natural origin. and added diluents/adulterants. Therefore, such studies generate relevant data that make it possible to establish connections between samples and materials of different seizures, classifying them into chemically correlated groups. Through these connections, it is possible to establish specific links among suppliers, drug dealers, and users, designing distribution network patterns and providing subsidies for the identification of the origin of the drug, including its geographical origin. Another striking forensic application of analytical chemistry is age determination and the authenticity of papers and inks. Once an ink is deposited on a support (paper), it is exposed to air, light, and moisture, and the following physical–chemical processes occur: coloration degradation, solvent evaporation, and hardening (polymerization) of the resins. These processes have been used in the complex task of determining the absolute or relative (comparative) age of manuscripts on paper. The largest number of publications refer to ballpoint pen inks. Ezcurra and collaborators published a comprehensive review on the dating of paints by modern instrument writers. Analytical paint dating exams essentially consist of quantifying how paint components vary over time. Last but not least, the authentication of pieces of art used as a tool to fight crime is a recent area of activity of analytical chemistry in Brazil. Operation Lava Jato shed light on the possibility that criminal use of the art market is a widespread method among agents of corruption and that it is much more complex and structured than previously thought. It is up to criminal experts to determine the authenticity of a piece of art. In general, the analytical investigations are guided by the identification and quantification of substances used in the production of the art piece, using non-destructive methodologies, such as Raman spectroscopy.
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Ruffing, Anne M., Stephen M. Anthony, Lucas M. Strickland, Ian Lubkin et Carter R. Dietz. « Identification of Metal Stresses in Arabidopsis thaliana Using Hyperspectral Reflectance Imaging ». Frontiers in Plant Science 12 (16 février 2021). http://dx.doi.org/10.3389/fpls.2021.624656.

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Industrial accidents, such as the Fukushima and Chernobyl disasters, release harmful chemicals into the environment, covering large geographical areas. Natural flora may serve as biological sensors for detecting metal contamination, such as cesium. Spectral detection of plant stresses typically employs a few select wavelengths and often cannot distinguish between different stress phenotypes. In this study, we apply hyperspectral reflectance imaging in the visible and near-infrared along with multivariate curve resolution (MCR) analysis to identify unique spectral signatures of three stresses in Arabidopsis thaliana: salt, copper, and cesium. While all stress conditions result in common stress physiology, hyperspectral reflectance imaging and MCR analysis produced unique spectral signatures that enabled classification of each stress. As the level of potassium was previously shown to affect cesium stress in plants, the response of A. thaliana to cesium stress under variable levels of potassium was also investigated. Increased levels of potassium reduced the spectral response of A. thaliana to cesium and prevented changes to chloroplast cellular organization. While metal stress mechanisms may vary under different environmental conditions, this study demonstrates that hyperspectral reflectance imaging with MCR analysis can distinguish metal stress phenotypes, providing the potential to detect metal contamination across large geographical areas.
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Cascella, Michele, et Thereza A. Soares. « Bias Amplification in Gender, Gender Identity, and Geographical Affiliation ». Journal of Chemical Information and Modeling, 19 mai 2022. http://dx.doi.org/10.1021/acs.jcim.2c00533.

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Damak, Fadwa, Mohamed Seddik Mahmoud Bougi, Daisuke Araoka, Koji Baba, Manami Furuya, Mohamed Ksibi et Kenji Tamura. « Soil geochemistry, edaphic and climatic characteristics as components of Tunisian olive terroirs : Relationship with the multielemental composition of olive oils for their geographical traceability ». Euro-Mediterranean Journal for Environmental Integration 6, no 1 (10 mars 2021). http://dx.doi.org/10.1007/s41207-021-00241-y.

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AbstractOlive oil traceability based on the intrinsic chemical composition of the oil is becoming increasingly important due to the prevalence of fraudulent geographical labelling of olive oils. For a traceability tool to be valid, it should be based on olive oil properties that are clearly related to provenance factors. However, multielement analysis of the oil has been used as a traceability tool without any proof of a direct link between the multielemental composition and the geographical origin of the oil. In order to verify this link, Tunisian olive terroir components from the 11 major olive-producing regions were sampled to evaluate the influences of these components (especially soil and climate) on the geochemical composition of Tunisian olive oil. Overall, geochemical processes relating to strontium and rare-earth element (REE) enrichment were found to control the multelemental compositions of Tunisian soils. Even though olive oils from the 11 Tunisian olive-growing regions considered did not strongly reflect the geochemical signatures of the corresponding Tunisian soils, the concentrations of four elements in the oils, namely Fe, Ti, Ni and Ba, showed significant positive Spearman correlations with their concentrations in the bioavailable extracts from those soils. Moreover, there were numerous significant correlations of elements in the olive oil with soil chemical and climate parameters. Our results clearly confirm that the complex interactions of the olives with the climate and soil chemistry during cultivation significantly affect the multielemental composition of the resulting olive oil. This finding implies that the elemental profile of the olive oil is an effective and valid marker of the geographical origin of the oil, as it is significantly linked to oil provenance factors. It also explains the discrepancies between the geochemical signature of an oil and that of the soil in which the olives were grown, as climate parameters affect the transfer of that signature from soil to olives. This work therefore provides the basis for a scientifically based approach to olive oil traceability. The results of this work can be utilized by agricultural authorities to realise the multielement-based traceability of olive oils from various Tunisian regions. Graphic abstract
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Gupta, Vijeta, Dr Tarun Virmani et Dr Vijender Singh. « A Comparative Diagnostic account of the Roots of Boerhavia diffusa Linn. From Four Different Geographical Regions in India ». International Journal of Agriculture and Animal Production, 20 mai 2022, 14–19. http://dx.doi.org/10.55529/ijaap.23.14.19.

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Boerhavia diffusa Linn (B. diffusa) belongs to the family Nyctaginaceae, commonly referred to as Punarnava. It is a rasayana plant that has anti-aging, disease prevention and life-building activities. In this study, B. diffusa Linn’s roots were collected from four different geographical locations in Indian territory i.e. Jhansi, Bangalore, Punjab and Delhi for comparative standardization. The study was carried out in accordance with WHO guidelines to determine the purity and correct identity of plant parts. It also helps detect adulterations, botanical verification, and physical and chemical parameters, and gives the notion of drug quality. In the present work, detailed comparative Pharmacognosy, morphology, anatomy and phytochemical studies of root of B.diffusa Linn from Four different geographical regions in India have been carried out. The results show that all four B.diffusa from different geographical regions revealed that all are very distinct. The anatomical parameters and physicochemical constants carried out in the present investigation serves as measures of a quality control for all the four plants i.e; Boerhavia diffusa Linn.(Jhansi, Bangalore, Pune and Delhi).
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Stilo, Federico, Marta Cialiè Rosso, Simone Squara, Carlo Bicchi, Chiara Cordero et Cecilia Cagliero. « Corylus avellana L. Natural Signature : Chiral Recognition of Selected Informative Components in the Volatilome of High-Quality Hazelnuts ». Frontiers in Plant Science 13 (25 avril 2022). http://dx.doi.org/10.3389/fpls.2022.844711.

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The volatile fraction of plant-based foods provides useful functional information concerning sample-related variables such as plant genotype and phenotype expression, pedoclimatic and harvest conditions, transformation/processing technologies, and can be informative about the sensory quality. In this respect, the enantiomeric recognition of the chiral compounds increases the level of information in profiling studies, being the biosynthesis of native compounds often stereo-guided. Chiral native volatiles mostly show an enantiomeric excess that enables origin authentication or support correlation studies between chemical patterns and sensory profiles. This study focuses, for the first time, on the enantiomeric composition of a large set of chiral compounds within the complex volatilome of Corylus avellana L. belonging to different cultivars (Tonda Gentile Romana, Tonda Gentile Trilobata, Anakliuri) and harvested in different geographical areas (Italian and Georgian). Besides native components profiled in raw kernels, volatiles formed after technological treatment (i.e., roasting) are also considered. Headspace solid-phase microextraction combined with enantioselective gas chromatography–mass spectrometry enables the accurate tracking and annotation of about 150 compounds across many samples. The results show that chiral compounds have diagnostic distribution patterns within hazelnut volatilome with cultivar and harvest region playing the major role. Moreover, being some of these chiral molecules also key-aromas, their distribution has a decisive impact on the sensory properties of the product. In particular, the enantiomeric composition of (E)-5-methyl-2-hepten-4-one (filbertone) resulted to be discriminant for origin authentication. The enantiomeric distribution showed, according to literature, an excess of the (S)-enantiomer in both raw and roasted samples volatilome with larger differences in raw samples. The amount of both (R) and (S)-filbertone increases during roasting; the most marked increase for (R)-enantiomer is observed in Italian samples, thus supporting evidence of better hedonic properties and more pleasant odor and aroma.
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