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Molecular Plant 2018年第1期11卷 31-46页

作者： William J. Barnes charles T. Anderson Department of Biology Center for Ugnocellulose Structure and Formation The Pennsylvania State University University Park PA 16802 USA

Plant cell walls contain elaborate polysaccharide networks and regulate plant growth, development, mechanics, cell-cell communication and adhesion, and defense. Despite conferring rigidity to support plant structures, the cell wall is a dynamic extracellular matrix that is modified, reorganized, and degraded to tightly control its properties during growth and development. Far from being a terminal carbon sink, many wall polymers can be degraded and recycled by plant cells, either via direct re-incorporation by trans- glycosylation or via internalization and metabolic salvage of wall-derived sugars to produce new precur- sors for wall synthesis. However, the physiological and metabolic contributions of wall recycling to plant growth and development are largely undefined. In this review, we discuss long-standing and recent evi- dence supporting the occurrence of cell-wall recycling in plants, make predictions regarding the develop- mental processes to which wall recycling might contribute, and identify outstanding questions and emerging experimental tools that might be used to address these questions and enhance our understanding of this poorly characterized aspect of wall dynamics and metabolism.

关键词： Plant cell walls wall degradation wall recycling wall biosynthesis

Mental health status in veterans residing in rural versus non-rural areas: results from the veterans’ health study

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Military Medical research 2021年第1期8卷 79-89页

作者： Joseph J.Boscarino charles r.Figley richard E.Adams Thomas G.Urosevich H.Lester Kirchner Joseph A.Boscarino Clinical Psychology Department William James CollegeNewtonMA 02459USA School of Social Work Tulane UniversityNew OrleansLA 70112USA Department of Sociology Kent State UniversityKentOH 44242USA Ophthalmology Service Geisinger ClinicMount PoconoPA 18344USA Department of Population Health Sciences Geisinger Clinic100 N.Academy Avenue44-00DanvillePA 17822USA

Background: The majority of Veterans Affair(VA) hospitals are in urban areas. We examined whether veterans residing in rural areas have lower mental health service use and poorer mental health ***: Veterans with at least 1 warzone deployment in central and northeastern Pennsylvania were randomly selected for an interview. Mental health status, including posttraumatic stress disorder(PTSD), major depression, alcohol abuse and mental health global severity, were assessed using structured interviews. Psychiatric service use was based on self-reported utilization in the past 12 months. results were compared between veterans residing in rural and non-rural areas. Data were also analyzed using multivariate logistic regression to minimize the influence by confounding ***: A total of 1730 subjects(55% of the eligible veterans) responded to the survey and 1692 of them had complete geocode information. Those that did not have this information(n=38), were excluded from some analyses. Veterans residing in rural areas were older, more often of the white race, married, and experienced fewer stressful events. In comparison to those residing in non-rural areas, veterans residing in rural areas had lower global mental health severity scores;they also had fewer mental health visits. In multivariate logistic regression, rural residence was associated with lower service use, but not with PTSD, major depression, alcohol abuse, and global mental health severity score after adjusting confounding factors(e.g., age, gender, marital status and education).Conclusions: rural residence is associated with lower mental health service use, but not with poor mental health in veterans with former warzone deployment, suggesting rural residence is possibly protective.

关键词： Veterans rural risk factors PTSD Alcohol abuse Depression Service use Census data

Influence of ship emissions on NOx, SO2, O3 and PM concentrations in a North-Sea harbor in France

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Journal of Environmental Sciences 2018年第9期30卷 56-66页

作者： Frederic Ledoux Cloe rochet Fabrice Cazier charles Beaugard Dominique Courcot Unit of Environmental Chemistry and Interactions with Life UCEIV EA4492 SFR Condorcet FR CNRS 3417 University of the Littoral OpalCoast F-59140 Dunlterque France Centre Commun de Mesures University of the Littoral Opal Coast F-59140 Dunkerque France Atmo Hauts-de-France F-59800 Lille France

The influence of in-port ship emissions on gases and PM10 concentrations has been estimated in the port city of Calais, northern France, one of the busiest harbor in Europe, with numerous rotations of ferries or roll-on/roll-off cargo in average per day. NOx, SO2, O3 and PM10 concentrations were continuously measured over a three-month period, as well as real-time particle size distribution. A rural site located at Cape Gris-Nez, 20 km from Calais, was considered to deduce intrinsic contribution of ship emissions at the harbor city. The average concentrations of the studied species as well as the pattern of the conditional bivariate probability function at the two sites evidenced that in-port shipping, especially during the maneuvering operations, has an important influence on the NOx and SO2 concentrations. The impact of shipping in the harbor of Calais on average concentrations was estimated to 5l% for SO2, 35% for NO, 15% for NO2 and 2% for PM10 in the studied period. Concentration peaks of SO2 and NOx associated with an 03 depletion appeared synchronized with departures and arrivals of ferries. For winds blowing from the harbor, when compared to the background level, the number of particles appeared 10 times higher, with the highest differences in the 30-67 nm and the 109-167 nm size ranges. The average impact of in-port ships on PM10 concentrations was estimated to ＋28.9 μg/m^3 and concerned mainly the PM1 size fraction （40%）. Punctually, PM10 can potentially reach a concentration value close to 100μg/m^3.

关键词： Ships Emissions Harbor Gases Particles Air pollution

The Physicochemical Changes of Farm-raised Pacific White Shrimp (<i>Litopenaeus vannamei</i>) as Influenced by Iced Storage

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Food and Nutrition Sciences 2015年第10期6卷 906-922页

作者： charles Odilichukwu r. Okpala School of Science Monash University Sunway Campus Bandar Sunway Malaysia Istituto per l’Ambiente Marino Costiero Consiglio Nazionale delle Ricerche Mazara del Vallo Italy

Farm-raised Pacific white shrimp (Litopenaeus vannamei) freshly harvested was evaluated for differences in proximal composition (moisture, ash, fat, and protein contents), water activity (aw), water retention index (WrI), pH, colour and texture of up to 12 days of iced storage. Shortly after harvest, the proximate composition of shrimp appeared comparable across the farms. With ice storage, the pH significantly increased whereas fat content slowly decreased particularly between days 3 and 9 (P P > 0.05). Expressly, the protein content of shrimp specimens gradually decreased after day 8 (P aw) of shrimp specimens exhibited inconsequential differences during iced storage. While the lightness (L*) was significantly affected from day 2 onwards, the yellowness (b*) colour was so but only between days 6 and 10 (P rdness textures of shrimp specimens registered peak values at day 11. Overall, the physicochemical differences in farm-raised shrimp during iced storage of this study provide valuable information for relevant stakeholders of the shrimp industry. Importantly, the data provided at this study can serve as baseline for comparison and evaluation of preservative treatments applied to shrimp.

关键词： Litopenaeus vannamei pH Moisture Colour Adhesiveness Hardness Water retention Index Physicochemical Differences

Using an Electronic Nose to rapidly Assess Grandlure Content in Boll Weevil Pheromone Lures

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Journal of Bionic Engineering 2011年第4期8卷 449-454页

作者： charles P.-C. Suh Ningye Ding Yubin Lan USDA-ArS Areawide Pest Management Research Unit College Station TX 77845 USA College of Engineering Northeast Agriculture University Harbin 150030 P. R. China

Samples of pheromone lures used in boll weevil, Anthonomus grandis （Boheman）, eradication programs are routinely analyzed by Gas Chromatography （GC） to ensure lures are adequately dosed with grandlure, the synthetic aggregation phero- mone produced by male weevils. However, preparation of GC samples is tedious, time consuming, and requires a moderate level of experience. We examined the use of a commercially-available electronic nose （e-nose） for rapidly assessing the grandlure contents of lures. The e-nose was trained to recognize headspace collections of grandlure emitted from new lures and after lures were aged under field conditions for 4 d, 7 d, 10 d, and 14 d. Based on cross-validation of the training set, the e-nose was 82% accurate in discriminating among the different age classes of lures. Upon sampling headspace collections of pheromone from a different set of field-aged lures, the e-nose was 〈50% accurate in discriminating 4 d, 7 d, and 10 d aged lures from the other age classes of lures. However, the e-nose identified new and 14 d aged lure samples with 100% accuracy. In light of these findings, e-nose technology shows considerable promise as an alternative approach for rapidly assessing the initial grandlure contents of lures used in boll weevil eradication programs.

关键词： electronic nose Cyranose 320 boll weevil grandlure pheromone lure

Assigning conservation value and identifying hotspots of endemic rattan diversity in the Western Ghats, India

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Plant Diversity 2017年第5期39卷 263-272页

作者： Mukta Joshi Bipin charles G. ravikanth N.A. Aravind Ashoka Trust for research in Ecology and the Environment (ATrEE) Royal Enclave Srirampura Jakkur PO Bangalore 560064 India Indian Institute of Sdence Education and research Dr. Homi Bhabha Road Pashan Pune 411008 India

rattans, or canes, are one of the most important non-timber forest products supporting the livelihood of many forest-dwelling communities in South and North-eastern India. Due to increased demand for rattan products, rattans have been extracted indiscriminately from the Western Ghats, a 1600-km mountain chain running parallel to the west coast of India. Extensive harvesting, loss of habitat and poor regeneration has resulted in dwindling rattan populations, necessitating an urgent attempt to conserve existing rattan resources. In this study, using niche-modelling tools, an attempt has been made to identify areas of high species richness of rattans in the Western Ghats, one of the mega-diversity regions of the world. We have also developed conservation values for 21 economically important and endemic rattans of the Western Ghats. We identified at least two to three sites of extremely high species richness outside the existing protected area network that should be prioritized for in situ *** study emphasizes the need to develop strategies for the long-term conservation of rattans in the Western Ghats, India.

关键词： Calamus NTFP Distribution Protected areas Gap analysis Species distribution models

Assessment of physically-based and data-driven models to predict microbial water quality in open channels

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Journal of Environmental Sciences 2010年第6期22卷 851-857页

作者： Minyoung Kim charles P.Gerba Christopher Y.Choi Agricultural Safety Engineering Division Department of Agricultural EngineeringNational Academy of Agricultural ScienceRural Development Administration(Korea) Department of Soil Waterand Environmental Sciencethe University of Arizona Department of Agricultural and Biosystems Engineering the University of Arizona

In the present study, a physically-based hydraulic modeling tool and a data-driven approach using artificial neural networks （ANNs） were evaluated for their ability to simulate the fate and transport of microorganisms in a water system. To produce reliable data, a pipe network was constructed and a series of experiments using a fecal coliform indicator （Escherichia coli 15597） was conducted. For the physically-based model, morphological （pipe size, link length, slope, etc.） and hydraulic （flow rate） conditions were used as input variables, and for ANNs, water quality parameters （conductivity, pH, and turbidity） were used. Both approaches accurately described the fate and transport of microorganisms （physically-based model： correlation coefficient （r） in the range of 0.914 - 0.977 and ANNs： r in the range of 0.949 - 0.980）, with the exception of one case at a low flow rate （q = 31.56 cm^3/sec）. This study also indicated that these approaches could be complementarily utilized to assess the vulnerability of water facilities and to establish emergency plans based on hypothetical scenarios.

关键词： transport open channel artificial neural networks Escherichia coli

Nitric oxide: orchestrating hypoxia regulation through mitochondrial respiration and the endoplasmic reticulum stress response

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Cell research 2005年第1期15卷 63-65页

作者： Ian G. charles,Salvador MONCADA Wolfson Institute for Biomedical research University College London The Cruciform Building Gower Street London WC1E 6BT UK Wolfson Institute for Biomedical research University College London The Cruciform Building Gower Street London WC1E 6BT UK

Mitochondria have long been considered to be the powerhouse of the living cell, generating energy in the form of the molecule ATP via the process of oxidative phosphorylation. In the past 20 years, it has been recognised that they also play an important role in the implementation of apoptosis, or programmed cell death. More recently it has become evident that mitochondria also participate in the orchestration of cellular defence *** physiological concentrations, the gaseous molecule nitric oxide (NO) inhibits the mitochondrial enzyme cytochrome c oxidase (complex IV) in competition with oxygen. This interaction underlies the mitochondrial actions of NO, which range from the physiologi- cal regulation of cell respiration, through mitochondrial signalling, to the development of “metabolic hypoxia” – a situation in which, although oxygen is available, the cell is unable to utilise it.

关键词： nitric oxide hypoxia mitochondria endoplasmic reticulum stress.

WEAK ErrOr ESTIMATES FOr TrAJECTOrIES OF SPDEs UNDEr SPECTrAL GALErKIN DISCrETIZATION

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Journal of Computational Mathematics 2018年第2期36卷 159-182页

作者： charles-Edouard Brehier Martin Hairer Andrew M. Stuart Univ Lyon CNRS Universite Claude Bernard Lyon 1 UMR5208 Institut Camille Jordan F-69622 Villeurbanne France Department of Mathematics Imperial College London London SW7 2AZ UK Computing and Mathematical Sciences California Institute of Technology 1200 E. California Blvd. MC 305-16 Pasadena CA 91125 USA

We consider stochastic semi-linear evolution equations which are driven by additive, spatially correlated, Wiener noise, and in particular consider problems of heat equation （analytic semigroup） and damped-driven wave equations （bounded semigroup） type. We discretize these equations by means of a spectral Galerkin projection, and we study the approximation of the probability distribution of the trajectories： test functions are regular, but depend on the values of the process on the interval [0, T]. We introduce a new approach in the context of quantative weak error analysis for discretization of SPDEs. The weak error is formulated using a deterministic function （It6 map） of the stochastic convolution found when the nonlinear term is dropped. The regularity properties of the It6 map are exploited, and in particular second-order Taylor expansions employed, to transfer the error from spectral approximation of the stochastic convolution into the weak error of interest. We prove that the weak rate of convergence is twice the strong rate of convergence in two situations. First, we assume that the covariance operator commutes with the generator of the semigroup： the first order term in the weak error expansion cancels out thanks to an independence property. Second, we remove the commuting assumption, and extend the previous result, thanks to the analysis of a new error term depending on a commutator.

关键词： Stochastic Partial Differential Equations Weak approximation Spectral Galerkin discretization

SYNTHESIS OF EXFOLIATED ISOTACTIC POLYPrOPYLENE/FUNCTIONAL ALKYL-TrIPHENYLPHOSPHONIUM-MODIFIED CLAY NANOCOMPOSITES BY IN SITU POLYMErIZATION

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Chinese Journal of Polymer Science 2013年第11期31卷 1501-1508页

作者： Kai Du 贺爱华 Fu-yong Bi charles C.Han Fine Chemicals Department Beijing Research Institute of Chemical IndustrySINOPEC State Key Laboratory of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and MaterialsBeijing National Laboratory for Molecular ScienceInstitute of ChemistryChinese Academy of Sciences Key Laboratory of rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsSchool of Polymer Science and EngineeringQingdao University of Science and Technology State Key Laboratory of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and MaterialsBeijingNational Laboratory for Molecular ScienceInstitute of ChemistryChinese Academy of Sciences

Diphenyl （4-hydroxyphenyl） hexadecyl phosphonium bromide （POH） -modified montmorillonite （POHMMT） was used to prepare a novel TiC14/MgC12/POHMMT compound catalyst and exfoliated iPP/POHMMT nanocomposites were prepared by the in situ intercalative polymerization of propylene with the TiC14/MgC12/POHMMT compound catalyst. The POH surfactants don＇t change the catalytic characteristic of the Z-N catalyst and the obtained PP presents high isotacticity, normal molecular weight and molecular weight distribution. The WAXD, SAXS and TEM results demonstrate the highly exfoliated iPP/POHMMT nanocomposites were produced by the in situ polymerization with this novel catalyst, while the intercalated iPP/Na＋MMT nanocomposites were produced with the TiC14/MgC12/Na＋MMT compound catalyst. Through this approach, in situ propylene polymerization can actually take place between the silicate layers and lead not only to PP with high isotacticity and molecular weight, but also to highly exfoliated PP nanocomposites.

关键词： Clay Nanocomposites Poly(propylene) (PP) Ziegler-Natta polymerization.