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71.
Leila Riahi Nejia Zoghlami Alexandre Fournier-Level Alexis Dereeper Loïc Le Cunff Valérie Laucou Ahmed Mliki Patrice This 《Genetic Resources and Crop Evolution》2013,60(3):1139-1151
In this study, two gene fragments corresponding to the VvMYBA1 and VvMYBA2 loci were sequenced on a sample of grapes including cultivated and wild accessions originating from Tunisia, Germany and France. A total of 42 SNPs were detected in the sequenced fragments giving an average of 1 SNP every 33 bp. High level of polymorphism was observed in the samples either in cultivated or wild accessions. Pattern of nucleotide diversity indicates a non departure from neutrality expectations for wild grapevine sample for gene VvMYBA1 and VvMYBA2 and for cultivated sample for gene VvMYBA1. However, a linkage to a selective sweep was revealed for cultivated grapevine gene pool in gene VvMYBA2. A genetic structure of the studied sample according to accession taxonomic status was revealed by the UPGMA clustering with a considerable overlap. This result was confirmed by significant but low genetic differentiation values between cultivated and wild sample. The number of migrants Nm based on sequence data information between Tunisian cultivars and Tunisian wild accessions showed a low level of gene flow between those germplasms. This finding indicates that Tunisian cultivars do not derive directly from local wild populations but could mostly correspond to imported materials introduced during historical times. However, the possibility that some cultivars derived from ancestral events of local domestication or cross hybridization with native wild plants was not completely excluded for Tunisian grapevine accessions. 相似文献
72.
Melissa R. Cronin Julia E. Amaral Alexis M. Jackson Jennifer Jacquet Katherine L. Seto Donald A. Croll 《Fish and Fisheries》2023,24(1):56-70
The incidental capture by marine fisheries as bycatch poses a global threat to pelagic sharks and rays. In large, industrialized fisheries that often operate in areas beyond national jurisdiction, at least 22 threatened species of pelagic elasmobranchs are caught as bycatch, representing the majority of megafauna bycatch in tuna fisheries. Here, we investigate (1) the efficacy of the current policies of the five tuna-related Regional Fisheries Management Organizations (tRFMOs) in mitigating elasmobranch bycatch, (2) data needed to better assess the amount and impact of elasmobranch bycatch and (3) the research necessary for the adoption of new policies. We found that tRFMOs have adopted 34 active policies that address pelagic elasmobranch bycatch. However, most policies (~76%, n = 26) are unlikely to avoid or minimize elasmobranch bycatch. Instead, most policies focus on mitigating post-capture mortality via remediation and requiring or encouraging research and data collection. Despite the emphasis on research mandates, we find that the existence of research was not related to policy adoption, suggesting that lack of research has not historically prohibited policymaking. Overall, we suggest that current research and data transparency, though perhaps not necessary for policy adoption, are not sufficient to adequately evaluate the population-level impacts of bycatch on many elasmobranch species in tRFMO-managed fisheries. Given these results, we recommend a precautionary approach that involves reforms in tRFMO voting processes to facilitate the adoption of binding requirements for elasmobranch catch limits, bycatch avoidance, pre- and post-capture handling and release modifications and protection of areas important to threatened pelagic elasmobranchs. 相似文献
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Anthony R. D’Amato Nicholas J. Schaub Jesus M. Cardenas Erich Franz Deniz Rende Alexis M. Ziemba Ryan J. Gilbert 《Fibers and Polymers》2017,18(3):483-492
Electrospun fiber scaffolds crafted from polyesters are studied extensively for potential tissue engineering applications. For translation of electrospun fibers into the clinic, the FDA requires analysis and quantification of any organic solvent that may be retained in the fibers since many organic solvents can negatively affect cells and tissues. If a significant amount of solvent is retained, then developing procedures for efficient solvent removal may enhance the clinical potential of these materials. In this study we use fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and nuclear magnetic resonance spectroscopy (NMR) to analyze solvent retention. A correlative analysis shows that both FTIR and TGA accurately predicted retention of two different solvents (HFP and chloroform) in our electrospun PLLA scaffolds, thus validating these procedures. We also assess the efficacy of various fiber treatment methods to facilitate organic solvent removal and conclude that submersion in 70 % ethanol and heat treatment at 100 °C were the most efficient methods of removing solvent from electrospun PLLA fibers. 相似文献
76.
Effects of Fish Meal Replacement by a Soybean Protein on Growth,Histology, Selected Immune and Oxidative Status Markers of Gilthead Sea Bream,Sparus aurata 下载免费PDF全文
Fotini Kokou Elena Sarropoulou Efthimia Cotou George Rigos Morgane Henry Maria Alexis Maroudio Kentouri 《Journal of the World Aquaculture Society》2015,46(2):115-128
The purpose of the trial was to study the impact of a 6‐mo dietary administration of soybean protein on growth, liver and intestine morphology, immune response, and oxidative stress in gilthead sea bream. The immune response was evaluated by performing immunological assays in blood, head kidney (HK), or serum (respiratory burst activity [RBA], myeloperoxidase content and bacteriolytic activity) and gene expression analysis of immune‐associated genes (MHCIIα [major histocompatibility complex IIα], β2m [β‐2‐microglobulin], CSF‐1R [colony‐stimulating factor‐1 receptor], NCCRP‐1 [nonspecific cytotoxic cell receptor protein 1], TGF‐β1 [transforming growth factor beta‐1], and HSP70 [heat‐shock protein 70]) in HK and intestine. Oxidative stress was evaluated by measuring the activity of liver enzymes associated with antioxidant system. The soybean protein was administrated in the diets at 20, 40, and 60% levels and its effects were evaluated compared with a fish meal diet. Growth and feed efficiency were affected negatively from 40% level. Increased RBA and expression levels of TGF‐β1 and β2m were found in HK only at 40% level. In intestine, at 60% level CSF‐1R expression was upregulated and some signs of inflammation were evident. In liver, at 60% level lipid accumulation in hepatocytes was observed and enzyme activity was increased. Dietary administration of soybean protein indicated changes from 40% in growth and immune response, and exerted an antioxidative effect at 60% level. 相似文献
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78.
Thomas F Randet C Gilbert A Silvestre V Jamin E Akoka S Remaud G Segebarth N Guillou C 《Journal of agricultural and food chemistry》2010,58(22):11580-11585
Until now, no analytical method, not even isotopic ones, had been able to differentiate between sugars coming from C4-metabolism plants (cane, maize, etc.) and some crassulacean acid metabolism plants (e.g., pineapple, agave) because in both cases the isotope distributions of the overall carbon-13/carbon-12 and site-specific deuterium/hydrogen isotope ratios are very similar. Following recent advances in the field of quantitative isotopic carbon-13 NMR measurements, a procedure for the analysis of the positional carbon-13/carbon-12 isotope ratios of ethanol derived from the sugars of pineapples and agave using the site-specific natural isotopic fractionation-nuclear magnetic resonance (SNIF-NMR) method is presented. It is shown that reproducible results can be obtained when appropriate analytical conditions are used. When applied to pineapple juice, this new method demonstrates a unique ability to detect cane and maize sugar, which are major potential adulterants, with a detection limit in the order of 15% of the total sugars, which provides an efficient mean of controlling the authenticity of juices made from this specific fruit. When applied to tequila products, this new method demonstrates a unique ability to unambiguously differentiate authentic 100% agave tequila, as well as misto tequila (made from at least 51% agave), from products made from a larger proportion of cane or maize sugar and therefore not complying with the legal definition of tequila. 相似文献
79.
Maurício Duarte-Almeida J Novoa AV Linares AF Lajolo FM Inés Genovese M 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(4):187-192
Phenolic compounds in sugar cane (Saccharum officinarum L.) juice were identified and quantified by analytical high performance liquid chromatography and photodiode array detection, showing the predominance of flavones (apigenin, luteolin and tricin derivatives), among flavonoids, and of hydroxycinnamic, caffeic and sinapic acids, among phenolic acids, representing a total content of around 160 mg/L. A tricin derivative was present in the highest proportion (>10% of the total). The phenolic extract obtained from sugar cane juice showed a protective effect against in vivo MeHgCl intoxication and potent inhibition of ex vivo lipoperoxidation of rat brain homogenates, indicating a potential use for beneficial health effects and/or therapeutic applications. 相似文献
80.
Sophie E. Hale Barry A. Gardiner Axel Wellpott Bruce C. Nicoll Alexis Achim 《European Journal of Forest Research》2012,131(1):203-217
Wind damage to forests is an important ecological disturbance factor. At the same time, it can have serious economic consequences
due to a reduction in timber production. Current models for predicting the risk of wind damage are useful, but generally only
focus on the “mean” tree within uniform stands. This paper presents measurements made of wind loading on trees of different
sizes within four forest stands of different structure and management history, but all well-acclimated to current wind conditions.
Each tree demonstrated a linear relationship between the maximum hourly turning moment and the square of the average hourly
wind speed at the canopy top; we defined this ratio (the gradient of the line M
max vs. u
2) as the turning moment coefficient (T
C). T
C was correlated with tree size, in a relationship that differed little between the four forest sites despite the differences
between the stands. The relationship between T
C and individual tree competition within each stand was investigated, using both distance-independent and distance-dependent
competition indices. All sites showed decreasing T
C with increasing competition. However, the relationships differed between sites and would also be expected to change through
time for a single site. The distance-dependent indices offered no improvement over the simpler, non-spatial indices that required
only a diameter distribution. We suggest how, subject to further work, the results presented could be applied to calculate
the risk of wind damage to trees of different sizes within a forest stand, and how the risk of wind damage to individual trees
might change in response to thinning. 相似文献