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51.
Ryan J. Quinn HakSoo Ha Timothy A. Volk Tristan R. Brown Steven Bick Robert W. Malmsheimer Marie‐Odile P. Fortier 《Global Change Biology Bioenergy》2020,12(9):728-741
Life cycle assessment (LCA) was combined with primary data from nine forest harvesting operations in New York, Maine, Massachusetts, and Vermont, from 2013 to 2019 where forest biomass (FB) for bioenergy was one of several products. The objective was to conduct a data‐driven study of greenhouse gas emissions associated with FB feedstock harvesting operations in the Northeast United States. Deterministic and stochastic LCA models were built to simulate the current FB bioenergy feedstock supply chain in the Northeast US with a cradle‐to‐gate scope (forest harvest through roadside loading) and a functional unit of 1.0 Mg of green FB feedstock at a 50% moisture content. Baseline LCA, sensitivity analysis, and uncertainty analyses were conducted for three different FB feedstock types—dirty chips, clean chips, and grindings—enabling an empirically driven investigation of differences between feedstock types, individual harvesting process contributions, and literature comparisons. The baseline LCA average impacts were lower for grindings (4.57 kg CO2eq/Mg) and dirty chips (7.16 kg CO2eq/Mg) than for clean chips (23.99 kg CO2eq/Mg) under economic allocation, but impacts were of similar magnitude under mass allocation, ranging from 24.42 to 27.89 kg CO2eq/Mg. Uncertainty analysis showed a wider range of probable results under mass allocation compared to economic allocation. Sensitivity analysis revealed the impact of variations in the production masses and total economic values of primary products of forest harvests on the LCA results due to allocation of supply chain emissions. The high variability in fuel use between logging contractors also had a distinct influence on LCA results. The results of this study can aid decision‐makers in energy policy and guide emissions reductions efforts while informing future LCAs that expand the system boundary to regional FB energy pathways, including electricity generation, transportation fuels, pellets for heat, and combined heat and power. 相似文献
52.
Dean A Sewell Tristan M Robinson Paul L Greenhaff 《Journal of applied physiology》2008,104(2):508-512
Due to the current lack of clarity, we examined whether 5 days of dietary creatine (Cr) supplementation per se can influence the glycogen content of human skeletal muscle. Six healthy male volunteers participated in the study, reporting to the laboratory on four occasions to exercise to the point of volitional exhaustion, each after 3 days of a controlled normal habitual dietary intake. After a familiarization visit, participants cycled to exhaustion in the absence of any supplementation (N), and then 2 wk later again they cycled to exhaustion after 5 days of supplementation with simple sugars (CHO). Finally, after a further 2 wk, they again cycled to exhaustion after 5 days of Cr supplementation. Muscle samples were taken at rest before exercise, at the time point of exhaustion in visit 1, and at subsequent visit time of exhaustion. There was a treatment effect on muscle total Cr content in Cr compared with N and CHO supplementation (P < 0.01). Resting muscle glycogen content was elevated above N following CHO (P < 0.05) but not after Cr. At exhaustion following N, glycogen content was no different from CHO and Cr measured at the same time point during exercise. Cr supplementation under conditions of controlled habitual dietary intake had no effect on muscle glycogen content at rest or after exhaustive exercise. We suggest that any Cr-associated increases in muscle glycogen storage are the result of an interaction between Cr supplementation and other mediators of muscle glycogen storage. 相似文献
53.
Luke J. Sutton Jayson C. Ibañez Dennis I. Salvador Rowell L. Taraya Guiller S. Opiso Tristan Luap P. Senarillos Christopher J. W. McClure 《Ibis》2024,166(1):156-170
Quantifying home-range size and habitat resource selection are important elements in wildlife ecology and are useful for informing conservation action. Many home-range estimators and resource selection functions are currently in use. However, both methods are fraught with analytical issues inherent within autocorrelated movement data from irregular sampling and interpretation of resource selection model parameters to inform conservation management. Here, we apply satellite remote sensing technologies to provide updated estimates of home-range size and first estimates of fine-scale resource selection for six adult Philippine Eagles Pithecophaga jefferyi using a space–time autocorrelated kernel density estimate (AKDE) home-range estimator and non-parametric resource selection functions. All six adult Eagles showed distinct site fidelity, with continuous range residency between 2 and 18 km, 1 month after tagging. The space–time AKDE home-range estimators had a median 95% home-range size = 68 km2 (95% confidence interval (95% CI) 62–74 km2, range: 39–161 km2), with the median 50% core range size = 13 km2 (95% CI 11–14 km2, range 9–33 km2). From the resource selection functions, all adult Philippine Eagles used habitat high in photosynthetic leaf and canopy structure but avoided areas of old-growth biomass and denser areas of vegetation. This is possibly due to foraging forays into secondary forest and fragmented agricultural areas away from nesting sites. For the first time, we determine two important fine-scale spatial processes for this Critically Endangered raptor that can help in directing conservation management. Rather than employing traditional home-range estimators and resource selection functions, we recommend that analysts consider space–time approaches and non-parametric resource selection functions to animal movement data to explore fully space–time and resource selection. 相似文献
54.
55.
Thomas Arnauld Jean-Yves Beaumal François Lefoulon Alain Petit Tristan Renaud 《Bioorganic & medicinal chemistry letters》2013,23(7):2217-2219
During the course of our study on the innovative ligand for nicotinic acetylcholinergic receptors, LNAChR, and in order to assess activity and toxicity profiles of the drug’s metabolites, synthesis of the main metabolites was undertaken. This synthesis work was done in parallel by organic chemistry and by biotransformation of LNAChR. Filamentous fungus Aspergillus alliaceus (NRRL 315) neatly afforded three of the main metabolites, one of which arose from a very unexpected and very uncommon rearrangement. 相似文献
56.
Qiang Tong Qing Cai Tristan de Mooij Xia Xu Shengming Dai Wenchun Qu Dongbao Zhao 《PloS one》2015,10(3)
Objective
This study aims to investigate the prevalence of short-term and long-term adverse events associated with tumor necrosis factor-α (TNF-α) blocker treatment in Chinese Han patients suffering from ankylosing spondylitis (AS).Methods
The study included 402 Chinese Han AS patients treated with TNF-α blockers. Baseline data was collected. All patients were monitored for adverse events 2 hours following administration. Long-term treatment was evaluated at 8, 12, 52 and 104 weeks follow-up for 172 patients treated with TNF-α blockers.Results
Short-term adverse events occurred in 20.15% (81/402), including rash (3.5%; 14/402), pruritus (1.2%; 5/402), nausea (2.2%; 9/402), headache (0.7%; 3/402), skin allergies (4.0%; 16/402), fever (0.5%; 2/402), palpitations (3.0%; 12/402), dyspnea (0.5%; 2/402), chest pain (0.2%; 2/402), abdominal pain (1.0%; 4/402), hypertension (2.2%; 9/402), papilledema (0.5%; 2/402), laryngeal edema (0.2%; 1/402) and premature ventricular contraction (0.2%; 1/402). Long-term adverse events occurred in 59 (34.3%; 59/172) patients, including pneumonia (7.6%; 13/172), urinary tract infections (9.9%; 17/172), otitis media (4.7%; 8/172), tuberculosis (3.5%; 17/172), abscess (1.2%; 2/172), oral candidiasis (0.6%; 1/172), elevation of transaminase (1.7%; 3/172), anemia (1.2%; 2/172), hematuresis (0.6%; 1/172), constipation (2.3%; 4/172), weight loss (0.6%; 1/172), exfoliative dermatitis (0.6%; 1/172). CRP, ESR and disease duration were found to be associated with an increased risk of immediate and long-term adverse events (P<0.05). Long-term treatment with Infliximab was associated with more adverse events than rhTNFR-Fc (P<0.01).Conclusion
This study reports on the prevalence of adverse events in short-term and long-term treatment with TNF-α blocker monotherapy in Chinese Han AS patients. Duration of disease, erythrocyte sedimentation rate, and c-reactive protein serum levels were found to be associated with increased adverse events with anti-TNF-α therapy. Long-term treatment with Infliximab was associated with more adverse events than rhTNFR-Fc. 相似文献57.
Since 2008, mass mortality outbreaks have been reported in all French regions producing Pacific oysters, and in several Member States of the European Union. These mass mortality events of Pacific oysters are related to OsHV-1 infection. They occur during spring and summer periods leaving suspect the quality of the marine environment and the role of seasonal use of pesticides associated with the arrival of freshwater in oyster rearing areas. Pesticides have been also detected in French coastal waters, especially in areas of oyster production. Using PMA real-time PCR we showed that a mixture of 14 pesticides has no effect on the integrity of virus capsids from viral suspension in the conditions tested. A contact of oysters with this pesticide mixture was related to higher mortality rates among experimentally infected animals in comparison with control ones (no previous pesticide exposure before experimental infection). We therefore suggest that pesticides at realistic concentration can exert adverse effects on Pacific oysters and causes an increased susceptibility to the viral infection in experimental conditions. 相似文献
58.
Lionel Dégremont Jean-Baptiste Lamy Jean-Fran?ois Pépin Marie-Agnès Travers Tristan Renault 《PloS one》2015,10(6)
The Pacific oyster, Crassostrea gigas, is the most important commercial oyster species cultivated in the world. Meanwhile, the ostreid herpesvirus 1 (OsHV-1) is one of the major pathogens affecting the Pacific oyster, and numerous mortality outbreaks related to this pathogen are now reported worldwide. To assess the genetic basis of resistance to OsHV-1 infection in spat C. gigas and to facilitate breeding programs for such a trait, if any exist, we compared the mortality of half- and full-sib families using three field methods and a controlled challenge by OsHV-1 in the laboratory. In the field, three methods were tested: (A) one family per bag; (B) one family per small soft mesh bag and all families inside one bag; (C) same as the previous methods but the oysters were individually labelled and then mixed. The mean mortality ranged from 80 to 82% and was related to OsHV-1 based on viral DNA detection. The narrow-sense heritability for mortality, and thus OsHV-1 resistance, ranged from 0.49 to 0.60. The high positive genetic correlations across the field methods suggested no genotype by environment interaction. Ideally, selective breeding could use method B, which is less time- and space-consuming. The narrow sense heritability for mortality under OsHV-1 challenge was 0.61, and genetic correlation between the field and the laboratory was ranged from 0.68 to 0.75, suggesting a weak genotype by environment interaction. Thus, most of families showing the highest survival performed well in field and laboratory conditions, and a similar trend was also observed for families with the lowest survival. In conclusion, this is the first study demonstrating a large additive genetic variation for resistance to OsHV-1 infection in C. gigas, regardless of the methods used, which should help in selective breeding to improve resistance to viral infection in C. gigas. 相似文献
59.
Frédérique Thonon Rym Boulkedid Tristan Delory Sophie Rousseau Mahasti Saghatchian Wim van Harten Claire O’Neill Corinne Alberti 《PloS one》2015,10(4)
Background
There is an increasing need to evaluate the production and impact of medical research produced by institutions. Many indicators exist, yet we do not have enough information about their relevance. The objective of this systematic review was (1) to identify all the indicators that could be used to measure the output and outcome of medical research carried out in institutions and (2) enlist their methodology, use, positive and negative points.Methodology
We have searched 3 databases (Pubmed, Scopus, Web of Science) using the following keywords: [Research outcome* OR research output* OR bibliometric* OR scientometric* OR scientific production] AND [indicator* OR index* OR evaluation OR metrics]. We included articles presenting, discussing or evaluating indicators measuring the scientific production of an institution. The search was conducted by two independent authors using a standardised data extraction form. For each indicator we extracted its definition, calculation, its rationale and its positive and negative points. In order to reduce bias, data extraction and analysis was performed by two independent authors.Findings
We included 76 articles. A total of 57 indicators were identified. We have classified those indicators into 6 categories: 9 indicators of research activity, 24 indicators of scientific production and impact, 5 indicators of collaboration, 7 indicators of industrial production, 4 indicators of dissemination, 8 indicators of health service impact. The most widely discussed and described is the h-index with 31 articles discussing it.Discussion
The majority of indicators found are bibliometric indicators of scientific production and impact. Several indicators have been developed to improve the h-index. This indicator has also inspired the creation of two indicators to measure industrial production and collaboration. Several articles propose indicators measuring research impact without detailing a methodology for calculating them. Many bibliometric indicators identified have been created but have not been used or further discussed. 相似文献60.
Kevin K.-C. Liu Peter Cornelius Terrell A. Patterson Yuan Zeng Stephanie Santucci Elizabeth Tomlinson Colleen Gibbons Tristan S. Maurer Ravi Marala Janice Brown Jimmy X. Kong Eunsun Lee Wendy Werner Zane Wenzel Chandra Vage 《Bioorganic & medicinal chemistry letters》2010,20(1):266-271
Based on our original pyrazine hit, CP-0809101, novel conformationally-restricted 5HT2c receptor agonists with 2-piperazin-azaindane scaffold were designed. Synthesis and structure–activity relationship (SAR) studies are described with emphasis on optimization of the selectivity against 5HT2a and 5HT2b receptors with excellent 2c potency. Orally-active and selective compounds were identified with dose–responsive in vivo efficacy in our pre-clinical food intake model. 相似文献