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The relationship between fire severity and burning efficiency for estimating wildfire emissions in Mediterranean forests

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林业研究:英文版 2023年第5期34卷 1195-1206页

作者： Bountouraby Balde Cristina Vega-Garcia Pere joan Gelabert Aitor Ameztegui Marcos Rodrigues Department of Agriculture and Forest engineering University of LleidaAv.Alcalde Rovira Roure19125198 LleidaSpain Department of Geography and Land Management University of ZaragozaPedro Cerbuna 1250009 SaragossaSpain

Forests are exposed to changing climatic conditions reflected by increasing drought and heat waves that increase the risk of wildfire ignition and *** variables such as rain and wind as well as vegetation structure,land configuration and forest management practices are all factors that determine the burning potential of *** assessment of emissions released by vegetation combustion is essential for determining greenhouse gases and air *** estimation of wildfire-related emissions depends on factors such as the type and fraction of fuel(i.e.,live biomass,ground litter,dead wood)consumed by the fire in a given area,termed the burning *** approaches estimate live burning efficiency from optical remote sensing *** study used a data-driven method to estimate live burning efficiency in a Mediterranean *** severity estimations from Lands at imagery(dNBR),which relate to fuel consumption,and quantitative field data from three national forest inventory data were combined to establish the relationship between burning severity and live burning *** proxies explored these relationships based on dNBR interval classes,as well as regres sion *** correlation results between live burning efficiency and dNBR for conifers(R=0.63)and broad-leaved vegetation(R=0.95)indicated ways for improving emissions *** estimations by severity class(low,moderate-low,moderate-high,and high)are provided for conifers(0.44-0.81)and broad-leaves(0.64-0.86),and regression models for the live fraction of the tree canopy susceptible to burning(7 branches,and leaves).The live burning efficiency values by severity class were higher than previous studies.

关键词： Forest wildfires emissions Greenhouse gases Satellite images

Prevalence and outcomes of pancreatic cystic neoplasms in liver transplant recipients

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World Journal of Gastroenterology 2017年第48期23卷 8526-8532页

作者： Ken Liu Vikram Joshi Louise van camp Qi-Wei Yang Judith e Baars Simone I Strasser Geoffrey W McCaughan Avik Majumdar Payal Saxena Arthur J Kaffes Sydney Medical School The University of Sydney AW Morrow Gastroenterology and Liver Centre Royal Prince Alfred Hospital Department of Radiology Royal Prince Alfred Hospital

AIM To determine the prevalence,characteristics and clinical course of pancreatic cystic neoplasms(PCNs) in liver transplantation(LT) *** We retrospectively studied consecutive patients who underwent LT between January 1998 to April 2016. Clinical and laboratory data were obtained from patient medical records. Imaging findings on computed tomography and magnetic resonance cholangiopancreatography were reviewed by two *** During the study period,872 patients underwent cadaveric LT. Pancreatic cysts were identified in 53/872(6.1%) and 31/53(58.5%) were PCNs [28 intraductal papillary mucinous neoplasm(IPMN),2 mucinous cystic neoplasm(MCN),1 serous cystadenoma]. Patients with PCNs exhibited less male predominance(55% vs 73%,P = 0.03) compared to patients without pancreatic cysts. Thirteen patients(42%) were diagnosed with PCN pre-LT while 18 patients(58%) developed PCN post-LT. The median size of PCNs was 13 mm [interquartile range(IQR) 10-20 mm]. All IPMNs were side-branch type. Most PCNs were found in the head and body of pancreas(37% each),followed by the tail(25%). Five patients underwent further evaluation with endoscopic ultrasound. Progress imaging was performed on 81% of patients. PCNs remained stable in size and number in all but 2 patients. During a median follow up of 39 mo(IQR 26-58 mo),the 2(6%) patients with MCN underwent pancreatectomy. No PCN patient developed pancreatic adenocarcinoma,while 5 died from illnesses unrelated to the PCN. Among patients without PCN,1/841(0.1%) developed pancreatic *** The prevalence of PCNs in LT recipients was similar to the general population(3.6%,31/872). Side-branch IPMNs do not appear to have accelerated malignant potential in post-LT patients,indicating the current surveillance guidelines are applicable to this group.

关键词： Pancreatic cystic neoplasm Intraductal papillary mucinous neoplasm Mucinous cystic neoplasm Liver transplantation Pancreatic adenocarcinoma Immunosuppression

Insights into nanoplastics effects on human health

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Science Bulletin 2020年第23期65卷 1966-1969页

作者： Mariana Teles joan Carles Balasch Miguel Oliveira Jordi Sardans Josep Penuelas Department of Cell Biology Physiology and ImmunologyUniversitat Autònoma de BarcelonaBellaterraBarcelona 08193Cpain Centre for environmental and Marine Studies Department of BiologyUniversity of AveiroAveiro 3810-193Partugal Consejo Superior de Investigaciones Científicas(CSIC) Global Ecology UnitCentre de Recerca Ecològica i Aplicacions Forestals(CREAF)Universitat Autònoma de Barcelona(CREAF-CSIC-UAB)BellaterraCatalonia E-08193Spain Centre de Recerca ecològica i Aplicacions Forestals(CReAF)Cendanyola del Valles Catalonia E-08193Spain

Plastics are ubiquitous. Their role as a cost-effective, chemically stable, versatile multipurpose material precluded early attempts to regulate plastic wastes and facilitated the, now widespread, planetary contamination. Left to slow UV decay and thermooxidative weathering, large plastics chip away into less than 5 mm fragments, or microplastics, which, in turn, can degrade further into nanoplastics. In the manufacturing process, several components,such as catalysts, solvents, stabilizers。

关键词：纳米塑料 plastics 人体健康

Collision Resolution MAC Protocols for Wireless Ad Hoc Networks

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Communications and Network 2013年第1期5卷 16-33页

作者： Xinhua Yang Tracy camp Tracy camp Department of electrical engineering & Computer Science Colorado School of Mines Golden USA

In wireless ad hoc networks, nodes cooperatively form a network without any infrastructure such as a BS/AP (base station or access point). The widely-used contention-based MAC protocol, Ieee 802.11b, is inefficient in multi-hop networks due to the hidden and exposed terminal problems. The most popular schedule-based MAC protocol, TDMA (time division multiple access), is difficult to implement in an ad hoc network due to the lack of infrastructure. The contribution of this paper is to provide the community novel and efficient MAC (medium access control) protocols (i.e., a collision resolution protocol) for a wireless ad hoc network without a centralized infrastructure. We propose two new MAC protocols (one distributed algorithm and one cluster-based algorithm) that use a collision resolution scheme for a network with a single BS/AP. We first compare the performance of our distributed algorithm with our cluster-based algorithm. Then, we compare our algorithm that performs better (i.e., our cluster-based algorithm) to TDMA in a two-hop network. The simulation results illustrate that our cluster-based algorithm provides higher throughput and lower delay than TDMA in a two-hop network.

关键词： Ad Hoc Networks Cluster-Based Algorithms Collision Resolution Scheme MAC Protocols

Seasonal Rainfall Forecasts for the Yangtze River Basin of China in Summer 2019 from an Improved Climate Service

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Journal of Meteorological Research 2020年第5期34卷 904-916页

作者： Philip e.BeTT Nicola MARTIN Adam A.SCAIFe Nick DUNSTONe Gill M.MARTIN Nicola GOLDING joan.e camp Peiqun ZHANG Chris D.HeWITT Leon HeRMANSON Chaofan LI Hong-Li ReN Ying LIU Min LIU Met Office Hadley Centre Exeter EXI 3PBUK Plymouth Marine Laboratory Plymouth PL13DHUK College of engineering Mathematics and Physical SciencesUniversity of ExeterDevon EX44QFUK Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081China University of Southern Queensland Toowoomba QLD 4350Australia Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Wuhan Regional Climate Center Wuhan 430074China

Rainfall forecasts for the summer monsoon season in the Yangtze River basin(YRB) allow decision-makers to plan for possible flooding, which can affect the lives and livelihoods of millions of people. A trial climate service was developed in 2016, producing a prototype seasonal forecast product for use by stakeholders in the region, based on rainfall forecasts directly from a dynamical model. Here, we describe an improved service based on a simple statistical downscaling approach. Through using dynamical forecast of an east Asian summer monsoon(eASM) index, seasonal mean rainfall for the upper and middle/lower reaches of YRB can be forecast separately by use of the statistical downscaling, with significant skills for lead times of up to at least three months. The skill in different sub-basin regions of YRB varies with the target season. The rainfall forecast skill in the middle/lower reaches of YRB is significant in May–June–July(MJJ), and the forecast skill for rainfall in the upper reaches of YRB is significant in June–July–August(JJA). The mean rainfall for the basin as a whole can be skillfully forecast in both MJJ and JJA. The forecasts issued in 2019 gave good guidance for the enhanced rainfall in the MJJ period and the near-average conditions in JJA. Initial feedback from users in the basin suggests that the improved forecasts better meet their needs and will enable more robust decision-making.

关键词： seasonal rainfall forecasts climate service Yangtze River basin(YRB) east Asian summer monsoon(eASM)

脊髓切片中运动神经元的膜片箝技术研究:一种分析药物作用的高效工具(英文)

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Acta Pharmacologica Sinica 2000年第6期21卷 29-37页

作者： joan J KeNDIG CA 94305 Department of Anesthesia Stanford University School of Medicine USA

AIM: To develop a tool for detailed analysis of spirally acting anesthetic and analgesic agents. MeTHODS: Studies were done on visually identified motor neurons in 400 uuuuuuuum thick spinal cord slices from 14-23 d old rats using patch clamp techniques. ethanol was used as a prototype general anesthetic agent. ReSULTS: Cell bodies in the ventrolateral horn identified as motor neurons by retrograde fluorescent labeling had a mean dimension of 32 ± 5 /Mm (x ± s, n = 25). Mean resting potential was - 62. 8 ± 2. 4 mV; input resistance was 44±24 MΩ (n = 19). Threshold was -44± 7 mV, and action potential amplitude 101 ± 9 mV from baseline. ethanol concentrations at and below 50-200 mmol/L decreased motor neuron excitability to the injected current; there was no effect on resting potential, but a variable reversible increase in input resistance. ethanol re-versibly depressed the excitatory postsynaptic potential, with a dose-response relationship similar to that previously observed for the population e

关键词：脊髓运动神经元乙醇醇类全身麻醉突触后机制

Use of granulocyte/monocytapheresis in ulcerative colitis:A practical review from a european perspective

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World Journal of Gastroenterology 2021年第10期27卷 908-918页

作者： eugeni Domènech joan-Ramon Grífols Ayesha Akbar Axel U Dignass Department of Gastroenterology Hospital Universitari Germans Trias i PujolBadalona 08916CataloniaSpain Department of Medicine Universitat Autònoma de BarcelonaBadalona 08916CataloniaSpain Centro de Investigaciones Biomédicas en Red de enfermedades Hepáticas y Digestivas(CIBeReHD) Badalona 08916CataloniaSpain Blood and Tissue Bank Hospital Universitari Germans Trias i PujolBadalona 08916CataloniaSpain IBD Unit St.Mark’s Hospital and Academic InstituteLondon HA13UJUnited Kingdom Department of Medicine I Agaplesion Markus HospitalGoethe-UniversityFrankfurt am Main 60431Germany

Half of the patients with ulcerative colitis require at least one course of systemic corticosteroids in their *** 75%of these patients will also require immunosuppressive drugs(i.e.,thiopurines or biological agents)in the mid-term to avoid *** drugs raise some concerns due to an increased risk of serious and opportunistic infections and cancer,particularly in elderly and co-morbid patients,underlining the unmet need for safer alternative ***/monocytapheresis(GMA),a Ce-marked,non-pharmacological procedure for the treatment of ulcerative colitis(among other immune-mediated diseases),remains the only therapy targeting neutrophils,the hallmark of pathology in ulcerative *** has proven its efficacy in different clinical scenarios and shows an excellent and unique safety *** spite of being a first line therapy in Japan,GMA use is still limited to a small number of centres and countries in *** this article,we aim to give an overview from a european perspective of the mechanism of action,recent clinical data on efficacy and practical aspects for the use of GMA in ulcerative colitis.

关键词： Granulocyte Monocyte Ulcerative colitis Inflammatory bowel disease Apheresis Safety

Rhizobium Lipo-chitooligosaccharide Signaling Triggers Accumulation of Cytokinins in Medicago truncatula Roots

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Molecular Plant 2015年第8期8卷 1213-1226页

作者： Arjan van Zeijl Rik H.M. Op den camp eva e. Deinum Tatsiana Charnikhova Henk Franssen Huub J.M. Op den camp Harro Bouwmeester Wouter Kohlen Ton Bisseling Rene Geurts Department of Plant Sciences Laboratory of Molecular Biology Wageningen University Droevendaalsesteeg 16708 PB Wageningen The Netherlands Department of Systems Biophysics FOM institute AMOLF Science Park 104 1098 XG Amsterdam The Netherlands Department of Plant Sciences Laboratory of Plant Physiology Wageningen University Droevendaalsesteeg 1 6708 PB Wageningen The Netherlands Department of Microbiology IWWR Radboud University Nijmegen Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands College of Science King Saud University Post Office Box 2455 Riyadh 11451 Saudi Arabia

Legume rhizobium symbiosis is initiated upon perception of bacterial secreted lipo-chitooligosaccharides （LCOs）. Perception of these signals by the plant initiates a signaling cascade that leads to nodule formation. Several studies have implicated a function for cytokinin in this process. However, whether cytokinin accu- mulation and subsequent signaling are an integral part of rhizobium LCO signaling remains elusive. Here, we show that cytokinin signaling is required for the majority of transcriptional changes induced by rhizo- bium LCOs. In addition, we demonstrate that several cytokinins accumulate in the root susceptible zone 3 h after rhizobium LCO application, including the biologically most active cytokinins, trans-zeatin and iso- pentenyl adenine. These responses are dependent on calcium- and calmodulin-dependent protein kinase （CCaMK）, a key protein in rhizobial LCO-induced signaling. Analysis of the ethylene-insensitive Mtein21 Mtsickle mutant showed that LCO-induced cytokinin accumulation is negatively regulated by ethylene. Together with transcriptional induction of ethylene biosynthesis genes, it suggests a feedback loop negatively regulating LCO signaling and subsequent cytokinin accumulation. We argue that cytokinin accumulation is a key step in the pathway leading to nodule organogenesis and that this is tightly controlled by feedback loops.

关键词： Medicago truncatula cytokinin ethylene rhizobium lipo-chitooligosaccharides CRe1

Polyethylene glycol 35 ameliorates pancreatic inflammatory response in cerulein-induced acute pancreatitis in rats

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World Journal of Gastroenterology 2020年第39期26卷 5970-5982页

作者： Ana Ferrero-Andrés Arnau Panisello-Roselló joan Roselló-Catafau emma Folch-Puy experimental Pathology Department Institut d'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones científicasBarcelona 08036CataloniaSpain experimental Pathology Department Institut d'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones científicasCentro de Investigación Biomédica en Red de Enfermedades Hepáticas y DigestivasInstitut d'Investigacions Biomèdiques August Pi i SunyerBarcelona 08036CataloniaSpain

BACKGROUND Acute pancreatitis(AP)is a sudden inflammatory process of the pancreas that may also involve surrounding tissues and/or remote *** and parenchymal cell death are common pathological features of this condition and determinants of disease *** glycols(PeGs)are nonimmunogenic,non-toxic water-soluble polymers widely used in biological,chemical,clinical and pharmaceutical *** To evaluate the protective effect of a 35-kDa molecular weight PeG(PeG35)on the pancreatic damage associated to cerulein-induced acute pancreatitis in vivo and in *** Wistar rats were assigned at random to a control group,a cerulein–induced AP group and a PeG35 treatment *** was induced by five hourly intraperitoneal injections of cerulein(50μg/kg/bw),while the control animals received saline ***35 was administered intraperitoneally 10 minutes before each cerulein injection in a dose of 10 mg/*** AP induction,samples of pancreatic tissue and blood were collected for ***42J pancreatic acinar cells were treated with increasing concentrations of PeG35 prior to exposure with tumor necrosis factorα(TNFα),staurosporine or *** severity of AP was determined on the basis of plasma levels of lipase,lactate dehydrogenase activity,pancreatic edema and histological *** evaluate the extent of the inflammatory response,the gene expression of inflammation-associated markers was determined in the pancreas and in AR42J-treated ***-induced cell death was also measured in models of in vivo and in vitro pancreatic *** Administration of PeG35 significantly improved pancreatic damage through reduction on lipase levels and tissue edema in cerulein-induced AP *** increased associated inflammatory response caused by cerulein administration was attenuated by a decrease in the gene expression of inflammation-related cytokines and inducible nitric oxide synthase enzyme in the *** contr

关键词： Acute pancreatitis Inflammation Polyethylene glycols Cytokines AR42J cells Cell death