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991.
Disruptions of circadian and biological rhythms as well as general anesthesia can induce sleep disorders, resulting in an increase in sleepiness and drowsiness and a decrease in vigilance. It has been previously shown that circadian time can influence the pharmacologic sensitivity and the duration of action of general anesthetics. Studies on interactions between general anesthesia and circadian rhythms are few, but all of them suggest an important role of general anesthetics on circadian rhythms. General anesthesia is a particular wake‐sleep state that could potentially alter circadian rhythms on the days following anesthesia. The aim of this review is to discuss the various effects of general anesthesia on animal and human circadian time structure. This topic is highly relevant to clinicians, especially those involved in that field of ambulatory practice responsible for post‐operative patient care, including patient recovery and fatigue. 相似文献
992.
Charlotte Descamps Sophie Mare Sophie Hugon Muriel Quinet Anne‐Laure Jacquemart 《Ecology and evolution》2020,10(13):6549-6561
- Water stress and increasing temperatures are two main constraints faced by plants in the context of climate change. These constraints affect plant physiology and morphology, including phenology, floral traits, and nectar rewards, thus altering plant–pollinator interactions.
- We compared the abiotic stress responses of two bee‐pollinated Boraginaceae species, Echium plantagineum, an annual, and Echium vulgare, a biennial. Plants were grown for 5 weeks during their flowering period under two watering regimes (well‐watered and water‐stressed) and three temperature regimes (21, 24, 27°C).
- We measured physiological traits linked to photosynthesis (chlorophyll content, stomatal conductance, and water use efficiency), and vegetative (leaf number and growth rate) and floral (e.g., flower number, phenology, floral morphology, and nectar production) traits.
- The physiological and morphological traits of both species were affected by the water and temperature stresses, although the effects were greater for the annual species. Both stresses negatively affected floral traits, accelerating flower phenology, decreasing flower size, and, for the annual species, decreasing nectar rewards. In both species, the number of flowers was reduced by 22%–45% under water stress, limiting the total amount of floral rewards.
- Under water stress and increasing temperatures, which mimic the effects of climate change, floral traits and resources of bee‐pollinated species are affected and can lead to disruptions of pollination and reproductive success.
993.
994.
Erwan Guy Saouter Chiara Perazzolo Laure Delphine Steiner 《The International Journal of Life Cycle Assessment》2011,16(8):795-802
Purpose
USEtox? (Rosenbaum et al. 2008) is a new model which can be used to calculate characterization factors for human and ecotoxicity impact categories used in life cycle assessment. The French ADEME-AFNOR (http://affichage-environnemental.afnor.org/) is currently considering this model to develop a new environmental labelling standard for consumer goods. The objective of this short study is to compare USEtox? impact scores with critical dilution volume (CDV) scores from the European Ecolabel (http://ec.europa.eu/environment/ecolabel), a well-established tool widely used in Europe aiming at discriminating environmental friendly products.Material and methods
The same range of chemicals (high scores to low scores) listed in both the USEtox? database and the EU Ecolabel detergent ingredient database (DID-list) were used for the comparison. The DID-list is a reference list, which contains agreed and verified fate and ecotoxicity data. The ranking was made based on two different ranking parameters, one from each model: the environmental impact score from USEtox? and the CDV from the EU Ecolabel. Additionally, a Spearman’s rank correlation (ρ) coefficient was calculated.Results and discussion
Sixty-nine chemicals common in personal care and cleaning products were selected for the comparison between USEtox? and EU Ecolabel methods. A “fair” agreement was found between the two models with a Spearman correlation coefficient ρ of 0.74, but a significant number of chemicals was ranked rather differently. The presence of outliers (i.e., different ranking) may be explained by several factors, which include the use of discrete versus continuous values to estimate the substance’s degradation constant. Another factor could be that the substances are grouped under classes in the DID-list, thus having average parameter values. The main factor though probably lays in the different sources of the physico-chemical, fate and ecotoxicity data within the two model databases and the different way they are used for the ranking parameter calculation.Conclusions
Provided there is scientific consensus (and full transparency) on the raw data, both USEtox? and EU Ecolabel methods are relevant for ranking chemicals based on their physico-chemical and toxicological properties, and therefore for calculating product environmental impact scores related to their hazard. However, the presence of a number of chemicals with different ranking scores creates the risk of inconsistent consumer product information when either the CDV (EU ecolabel) or USEtox? (French “Affichage Environnemental”) is used for environmental labelling. To date, and for sake of consistency with an existing and used labelling scheme, the CDV appears much easier to implement with less uncertainty to calculate ecotoxicity impact score of products.995.
Andrs Meynard Javier Zapata Nicols Salas Claudia Betancourtt Gabriel Prez‐Lara Francisco Castaeda María Eliana Ramírez Cristian Bulboa Contador Marie‐Laure Guillemin Loretto Contreras‐Porcia 《Journal of phycology》2019,55(2):297-313
A recent molecular taxonomic study along the Chilean coast (18° S–53° S) described 18 candidate species of bladed Bangiales of which only two were formally described. Few studies focused on local genetic and morphological diversity of bladed Bangiales and attempted to determine their intertidal distribution in contrasting habitats, and none were performed in Chile. To delimit intertidal distributions of genetic species, 66 samples of bladed Bangiales were collected at Maitencillo (32° S) in four zones: a rocky platform, a rocky wall, and two boulders zones surrounded by sandy and rocky bottoms, respectively. These samples were identified based on sequences of the mitochondrial COI and chloroplast rbcL markers. We also collected 87 specimens for morphological characterization of the most common species, rapidly assessing their putative species identity using newly developed species‐diagnostic (PCR‐RFLP) markers. Eight microscopic and two macroscopic morphological traits were measured. We described and named three of four species that predominate in Maitencillo (including Pyropia orbicularis): Pyropia variabilis Zapata, Meynard, Ramírez, Contreras‐Porcia, sp. nov., Porphyra luchea Meynard, Ramírez, Contreras‐Porcia sp. nov., and Porphyra longissima Meynard, Ramírez, Contreras‐Porcia, sp. nov. With the exception of Po. longissima restricted to boulders surrounded by sandy bottom, and a morphotype of Py. variabilis restricted to rocky walls, the other species/morphotypes have overlapping intertidal distributions. Except for Po. longissima, which is clearly differentiated morphologically (longest and thinnest blades), we conclude that morphology is not sufficient to differentiate bladed Bangiales. Our findings underscore the importance of refining our knowledge of intrinsic and environmental determinants on the distribution of bladed Bangiales. 相似文献
996.
Patouillard Laure Collet Pierre Lesage Pascal Tirado Seco Pablo Bulle Cécile Margni Manuele 《The International Journal of Life Cycle Assessment》2019,24(12):2238-2254
The International Journal of Life Cycle Assessment - Regionalization in life cycle assessment (LCA) aims to increase the representativeness of LCA results and reduce the uncertainty due to spatial... 相似文献
997.
998.
Claire E. Holland Erin Papworth Serge C. Billong Sethson Kassegne Fanny Petitbon Valentin Mondoleba Laure Vartan Moukam Isaac Macauley Simon Pierre Eyene Ntsama Yves Roger Yomb Jules Eloundou Franz Mananga Ubald Tamoufe Stefan D. Baral 《PloS one》2015,10(4)
Background
Men who have sex with men (MSM) are more likely to be living with HIV than other adult men in low- and middle-income countries. MSM experience barriers to accessing HIV services including a lack of available specialized care, and community-level stigma and discrimination. This study aims to examine the uptake of HIV services at non-governmental and community-based organizations (NGOs/CBOs) to identify ways to improve coverage of HIV prevention and treatment among MSM.Methods
An Integrated Biological and Behavioral Surveillance (IBBS) survey was conducted in Yaoundé and Douala, Cameroon in 2011 using the respondent driven sampling (RDS) method to recruit and interview 239 MSM in Yaoundé and 272 MSM in Douala.Results
MSM in Yaoundé were statistically significantly more likely to have accessed NGO/CBO services or been reached by an outreach worker in the past 12 months if they had any STI symptoms (aOR 2.17 CI 1.02-4.59. p=0.04), or if they had a larger MSM social network (aOR 1.02 CI 1.01-1.04. p<0.01). MSM in Douala were more likely to have accessed NGO/CBO services or been reached by an outreach worker in the past 12 months if they were living with HIV (aOR 3.60 CI 1.35-9.60. p=0.01), or if they reported higher numbers of male sexual partners (aOR 1.17 CI 1.00-1.36. p=0.046). Compared to men in Douala, MSM in Yaoundé were significantly less likely to have accessed NGO/CBO services or been reached by an outreach worker in the past 12 months (aOR 0.22 CI 0 .14-0.34. p=<0.01).Conclusions
With appropriate funding and resources, community-based organizations that provide care specifically for MSM can improve access to HIV prevention, treatment, and care services. Additionally, using social networks to reach MSM can connect greater numbers of the population to effective HIV interventions, which will improve health outcomes and decrease onward transmission of HIV. 相似文献999.
Jérémie Rudant Laurent Orsi Audrey Bonaventure Stéphanie Goujon-Bellec André Baruchel Arnaud Petit Yves Bertrand Brigitte Nelken Marlène Pasquet Gérard Michel Laure Saumet Pascal Chastagner Stéphane Ducassou Yves Réguerre Denis Hémon Jacqueline Clavel 《PloS one》2015,10(3)
Genome-wide association studies (GWAS) have identified that frequent polymorphisms in ARID5B and IKZF1, two genes involved in lymphoid differentiation, increase the risk of childhood acute lymphoblastic leukemia (ALL). These findings markedly modified the current field of research on the etiology of ALL. In this new context, the present exploratory study investigated the possible interactions between these at-risk alleles and the non-genetic suspected ALL risk factors that were of sufficient prevalence in the French ESCALE study: maternal use of home insecticides during pregnancy, preconception paternal smoking, and some proxies for early immune modulation, i.e. breastfeeding, history of common infections before age one year, and birth order. The analyses were based on 434 ALL cases and 442 controls of European origin, drawn from the nationwide population-based case-control study ESCALE. Information on non-genetic factors was obtained by standardized telephone interview. Interactions between rs10740055 in ARID5B or rs4132601 in IKZF1 and each of the suspected non-genetic factors were tested, with the SNPs coded as counts of minor alleles (trend variable). Statistical interactions were observed between rs4132601 and maternal insecticide use (p = 0.012), breastfeeding p = 0.017) and repeated early common infections (p = 0.0070), with allelic odds ratios (OR) which were only increased among the children not exposed to insecticides (OR = 1.8, 95%CI: 1.3, 2.4), those who had been breastfed (OR = 1.8, 95%CI: 1.3, 2.5) and those who had had repeated early common infections (OR = 2.4, 95%CI: 1.5, 3.8). The allelic ORs were close to one among children exposed to insecticides, who had not been breastfed and who had had no or few common infections. Repeated early common infections interacted with rs10740055 (p = 0.018) in the case-only design. Further studies are needed to evaluate whether these observations of a modification of the effect of the at-risk alleles by non-genetic factors are chance findings or reflect true underlying mechanisms. 相似文献
1000.
Potential of a tomato MAGIC population to decipher the genetic control of quantitative traits and detect causal variants in the resequencing era 下载免费PDF全文
Laura Pascual Nelly Desplat Bevan E. Huang Aurore Desgroux Laure Bruguier Jean‐Paul Bouchet Quang H. Le Betty Chauchard Philippe Verschave Mathilde Causse 《Plant biotechnology journal》2015,13(4):565-577
Identification of the polymorphisms controlling quantitative traits remains a challenge for plant geneticists. Multiparent advanced generation intercross (MAGIC) populations offer an alternative to traditional linkage or association mapping populations by increasing the precision of quantitative trait loci (QTL) mapping. Here, we present the first tomato MAGIC population and highlight its potential for the valorization of intraspecific variation, QTL mapping and causal polymorphism identification. The population was developed by crossing eight founder lines, selected to include a wide range of genetic diversity, whose genomes have been previously resequenced. We selected 1536 SNPs among the 4 million available to enhance haplotype prediction and recombination detection in the population. The linkage map obtained showed an 87% increase in recombination frequencies compared to biparental populations. The prediction of the haplotype origin was possible for 89% of the MAGIC line genomes, allowing QTL detection at the haplotype level. We grew the population in two greenhouse trials and detected QTLs for fruit weight. We mapped three stable QTLs and six specific of a location. Finally, we showed the potential of the MAGIC population when coupled with whole genome sequencing of founder lines to detect candidate SNPs underlying the QTLs. For a previously cloned QTL on chromosome 3, we used the predicted allelic effect of each founder and their genome sequences to select putative causal polymorphisms in the supporting interval. The number of candidate polymorphisms was reduced from 12 284 (in 800 genes) to 96 (in 54 genes), including the actual causal polymorphism. This population represents a new permanent resource for the tomato genetics community. 相似文献