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Canopy gap size influences niche partitioning of the ground-layer plant community in a northern temperate forest

Journal of Plant Ecology 2013年第1期6卷 92-100页

作者： Christel C.Kern Rebecca A.Montgomery peter b.Reich Terry F.Strong USDA Forest Service Northern Research Station1831 Hwy 169 EastGrand RapidsMN 55744USA Department of Forest Resources University of Minnesota-Twin Cities1530 North Cleveland AvenueSaint PaulMN 55108USA Hawkesbury Institute for the Environment University of Western SydneyLocked Bag 1797Penrith NSW 2751Australia USDA Forest Service USARetired

Aims The Gap Partitioning Hypothesis(GPH)posits that gaps create heterogeneity in resources crucial for tree regeneration in closed-canopy forests,allowing trees with contrasting strategies to coexist along resource *** studies have examined gap partitioning of temperate,ground-layer vascular *** used a ground-layer plant community of a temperate deciduous forest in northern Wisconsin,USA,as a model system to test whether the GPH extends to the relatively species-rich ground *** We used a well-replicated experimental approach that included a gap opening gradient(five gap sizes,6,10,20,30 and 46 m diameter,and undisturbed reference areas),a within-gap location gradient(gap edge to center),and a temporal gradient(0,2,6 and 13 years after gap creation).The data were observations of ground-layer plant abundance,published plant traits,and a modeled index of understory light *** ordinated the plant abundance data and evaluated the relationships of composition,traits and light environment by gap size,location along the forest-gap transect and time,with several approaches such as correlations,descriptive statistics,non-parametric tests of group differences and indicator species importance *** Findings Ground-layer plant composition and traits differed across gap sizes,within-gap locations and over *** of all sizes differed in composition from undisturbed areas,and all pair-wise combinations of gap size also differed in composition,except the 6 m from the 10-m *** gaps(46 m)also displayed within-gap compositional gradients from gap edge to center *** differences in gap size were evident 2 years after gap creation and,contrary to our hypotheses,remained different over the 13-year period,even in gaps with crown *** contrast to the neutral theory,species functional traits and microenvironmental conditions were related to variation in ground-layer *** with smaller seeds,low

关键词： herbaceous layer experimental gaps proximity to edge functional diversity plant traits

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Development of a sample preparation approach to measure the size of nanoparticle aggregates by electron microscopy

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Particuology 2019年第4期17卷 49-57页

作者： Agnieszka Dudkiewicz Angela Lehner Qasim Chaudhry Kristian Molhave Guenter Allmaier Karen Tiede Alistair b.A. boxall peter Hofmann John Lewis The Food and Environment Research Agency Sand Hutton York Y041 1LZ UK Department of Environment The University of York Heslington York YO10 5DD UK National Centre for Food Manufacturing The University of Lincoln Holbeach PE12 7AG UK Research Group bio- and Polymer Analysis Institute of Chemical Technologies and Analytics TU Wien (Vienna University of Technology) Getreidemarkt 9 A-1060 Vienna Austria University of Chester Parkgate Road Chester CH1 4BJ UK Department of Micro and Nanotechnology Technical University of Denmark DTU Bldg 345b Lyngby 2800 Denmark Research Centre for Global Food Security and Ecosystems University of Hohenheim Wollgrasweg 43 70155 Stuttgart Germany Department of Geoinformatics - Z.GIS University of Salzburg Schillerstr. 30 A-5020 Salzburg Austria

Electron microscopy (EM) is widely used for nanoparticle (NP) sizing. Following an initial assessment of two sample preparation protocols described in the current literature as"unperturbed", we found that neither could accurately measure the size of NPs featuring a broad size distribution, e.g., aggregates. because many real-world NP samples consist of aggregates, this finding was of considerable concern. The data showed that the protocols introduced errors into the measurement by either inducing agglomeration artefacts or providing a skewed size distribution towards small particles (skewing artefact). The focus of this work was to develop and apply a mathematical refinement to correct the skewing artefact. This refinement provided a much improved agreement between EM and a reference methodology, when applied to the measurement of synthetic amorphous silica NPs. Further investigation, highlighted the influence of NP chemistry on the refinement. This study emphasised the urgent need for greater and more detailed consideration regarding the sample preparation of NP aggregates to routinely achieve accurate measurements by EM. This study also provided a novel refinement solution applicable to the size characterisation of silica and c让rate-coated gold NPs featuring broad size distributions. With further research, this approach could be extended to other NP types.

关键词： Nanoparticles Aggregates Measurement Electron microscopy Sample preparation Artefacts

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Grid Integration of Wind Generation Considering Remote Wind Farms:Hybrid Markovian and Interval Unit Commitment

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IEEE/CAA Journal of Automatica Sinica 2017年第2期4卷 205-215页

作者： bing Yan Haipei Fan peter b.Luh Khosrow Moslehi Xiaoming Feng Chien Ning Yu Mikhail A.bragin Yaowen Yu IEEE Department of Electrical & Computer Engineering University of Connecticut University of Connecticut Abb Inc. Abb Enterprise Software

Grid integration of wind power is essential to reduce fossil fuel usage but challenging in view of the intermittent nature of ***,we developed a hybrid Markovian and interval approach for the unit commitment and economic dispatch problem where power generation of conventional units is linked to local wind states to dampen the effects of wind ***,to reduce complexity,extreme and expected states are considered as interval *** this approach is effective,the fact that major wind farms are often located in remote locations and not accompanied by conventional units leads to conservative ***,weights of extreme and expected states in the objective function are difficult to tune,resulting in significant differences between optimization and simulation *** this paper,each remote wind farm is paired with a conventional unit to dampen the effects of wind uncertainties without using expensive utility-scaled battery storage,and extra constraints are innovatively established to model ***,proper weights are derived through a novel quadratic fit of cost *** problem is solved by using a creative integration of our recent surrogate Lagrangian relaxation and *** demonstrate modeling accuracy,computational efficiency,and significant reduction of conservativeness of the previous approach.

关键词： branch-and-cut interval optimization Markov decision process remote wind farms surrogate Lagrangian relaxation(SLR) unit commitment

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Association between calcium sensing receptor gene polymorphisms and chronic pancreatitis in a US population:Role of serine protease inhibitor Kazal 1type and alcohol

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World Journal of Gastroenterology 2008年第28期14卷 4486-4491页

作者： Venkata Muddana Janette Lamb Julia b Greer beth Elinoff Robert H Hawes peter b Cotton Michelle A Anderson Randall E brand Adam Slivka David C Whitcomb Division of Gastroenterology Hepatology and NutritionDepartment of MedicineUniversity of Pittsburgh Medical CenterPittsburgh PA 15213United States Digestive Disorder Center Medical University of South CarolinaCharleston SC 29403United States Department of Medicine University of Michigan Medical CenterAnn Arbor MI 48109United States Department of medicine Northwestern Universityand Currently at University of Pittsburgh Medical CenterPittsburgh PA 15213United States Division of Gastroenterology Hepatology and NutritionDepartment of MedicineUniversity of Pittsburgh Medical CenterPittsburgh PA 15213United States Department of Human GeneticsUniversity of PittsburghPittsburgh PA 15213United States

AIM： To test the hypothesis that calcium sensing receptor （CASR） polymorphisms are associated with chronic pancreatitis （CP）, and to determine whether serine protease inhibitor Kazal 1type （SPINK1） N34S or alcohol are necessary co-factors in its etiology. METHODS： Initially, 115 subjects with pancreatitis and 66 controls were evaluated, of whom 57 patients and 21 controls were predetermined to carry the high-risk SPINK1 N34S polymorphism. We sequenced CASR gene exons 2, 3, 4, 5 and 7, areas containing the majority of reported polymorphisms and novel mutations. based on the initial results, we added 223 patients and 239 controls to analyze three common nonsynonymous single nucleotide polymorphisms （SNPs） in exon 7 （A986S, R990G, and Q1011E）. RESULTS： The CASR exon 7 R990G polyrnorphism was significantly associated with CP （OR, 2.01; 95% CI, 1.12-3.59; P = 0.015）. The association between CASR R990G and CP was stronger in subjects who reported moderate or heavy alcohol consumption （OR, 3.12; 95% CI, 1.14-9.13; P = 0.018）. There was no association between the various CASR genotypes and SPINK1 N34S in pancreatitis. None of the novel CASR polymorphisms reported from Germany and India was detected. CONCLUSION： Our United States-based study confirmed an association of CASR and CP and for the first time demonstrated that CASR R990G is a significant risk factor for CP. We also conclude that the risk of CP with CASR R990G is increased in subjects with moderate to heavy alcohol consumption.

关键词： Calcium sensing receptor Serine protease inhibitor Kazal llype Chronic pancreatitis Alcohol

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Chlorophyll, anthocyanin, and gas exchange changes assessed by spectroradiometry in Fragaria chiloensis under salt stress

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Journal of Integrative Plant biology 2014年第5期56卷 505-515页

作者： Miguel Garriga Jorge b. Retamales Sebastián Romero-bravo peter D.S. Caligari Gustavo A. Lobos Faculty of Agricultural Sciences Plant Breeding and Phenomic Center Universidad de Talca Instituto de biología Vegetaly biotecnología Universidad de Talca

Chlorophyll and anthocyanin contents provide a valuable indicator of the status of a plant’s physiology, but to be more widely utilized it needs to be assessed easily and non‐destructively. This is particularly evident in terms of assessing and exploiting germplasm for plant‐breeding programs. We report, for the first time, experiments with Fragaria chiloensis（L.）Duch. and the estimation of the effects of response to salinity stress（0, 30, and 60 mmol NaCl/L） in terms of these pigments content and gas exchange. It is shown that both pigments（which interestingly, themselves show a high correlation） give a good indication of stress response. both pigments can be accurately predicted using spectral reflectance indices（SRI）;however, the accuracy of the predictions was slightly improved using multilinear regression analysis models and genetic algorithm analysis. Specifically for chlorophyll content, unlike other species, the use of published SRI gave better indications ofstress response than Normalized Difference Vegetation *** effect of salt on gas exchange is only evident at the highest concentration and some SRI gave better prediction performance than the known Photochemical Reflectance Index. This information will therefore be useful for identifying tolerant genotypes to salt stress for incorporation in breeding programs.

关键词： Gas exchange high‐throughput phenotyping pigment phenomic photosynthesis reflectance spectral reflectance indices

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Synergistic effects of interferon-alpha in combination with chemoradiation on human pancreatic adenocarcinoma

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World Journal of Gastroenterology 2005年第10期11卷 1521-1528页

作者： Jian-Hua Ma Emilia Patrut Jan Schmidt Hanns-peter Knaebel Markus W. büchler Angela M(a|¨)rten Department of Surgery

AIM: To determine whether IFN-α is the agent that turns a slightly effective treatment (radiochemotherapy) into a potent therapy, we tested IFN-α for its synergistic ***: Eight pancreatic carcinoma cell lines were treated with the single agents and combinations of *** role of IFN-α regarding a) direct inhibitory effects; b)radio and chemosensitizing effects; c) anti-angiogenic properties and d) enhancement of immunogenicity was ***: Our results show that IFN-α has direct inhibitory properties and some synergistic influence as determined by AnnexinV/PI stain and cell count. IFN-α is also able to prevent the increase in proliferation rate and VEGF secretion of CDDP resistant cells. Having taken the results from immunogenicity experiments together, we found cells that can be influenced by IFN-α but were less susceptible against T cells. Furthermore, high expression of MHC molecules, CD118, EGF-R and Fas was predictive for a good ***: In conclusion, IFN-α has direct cytotoxic effects, acts as a radiosensitizer and circumvents tumor cell-regrowth after CDDP treatment. These mechanisms may be responsible for the good clinical outcome of CapRI.

关键词： Interferon-alpha Pancreatic adenocarcinoma Synergistic effects Combination therapy

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Mapping wetlands in Indonesia using Landsat and PALSAR data-sets and derived topographical indices

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Geo-Spatial Information Science 2014年第1期17卷 60-71页

作者： belinda A.MARGONO Jean-Robert b.bWANGOY peter V.POTAPOV Matthew C.HANSEN Department of Geographical Sciences University of Maryland4321 Hartwick Bld.College ParkMD 20742USA GIS Center of Excellence South Dakota State University1021 Medary Ave.Wecota HallBrookingsSD 57007USA The Ministry of Forestry(MoF)of Indonesia Manggala Wanabhkati Bld.Jakarta 10270Indonesia

Wetlands play an important role in the provision of ecosystem services,ranging from the regulation of hydrological systems to carbon sequestration and biodiversity *** paper reports the mapping of Indonesia’s wetland cover as a single thematic class,including peatlands,freshwater wetlands,and ***-interpreted training data were used to identify wetland formations including areas of likely past wetland extent that have been converted to other land *** indices(Shuttle Radar Topography Mission-derived)and optical(Landsat)and radar(PALSAR)image inputs were used to build a bagged classification tree model based on training data in order to generate a national-scale map of wetland extent at a 60 m spatial *** resulting wetland map covers 21.0%(39.6 Mha)of Indonesia’s land,including 25.2% of Sumatra(11.9 Mha),22.9% of Kalimantan(12.2 Mha),and 28.9% of Papua(11.8 Mha).Results agree with existing image-interpreted products from Indonesia’s Ministries of Forestry and Agriculture and Wetlands International(89% overall agreement),and with the Ministry of Forestry forest inventory data for Sumatra and Kalimantan(91% overall agreement).An internally consistent algorithm-derived national wetland extent map can be used to quantify changing rates of land conversion inside and outside of ***,wetlands extent can be used to efficiently allocate field resources in national assessments of wetland sub-types such as peatlands,which are a current focus of policies aiming to reduce carbon emissions from land use change.

关键词： wetlands Indonesia remote sensing Landsat digital elevation model(DEM) PALSAR Shuttle Radar Topography Mission(SRTM)

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离子淌度谱和SIMPLISMA用于痕量有机化合物的检测

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光谱学与光谱分析 2005年第9期25卷 1530-1533页

作者：张卓勇陈国祥 Harrington peter de b 首都师范大学化学系 Department of Chemistry and biochemistry Center for Intelligent Chemical Instrumentation Clippinger Laboratories Ohio University Athens Ohio 45701-2979 USA

离子淌度谱(IMS)是检测痕量挥发性有机化合物的灵敏方法。SIMPLISMA(simpletouseinteractiveselfmodelingmixtureanalysis)是一种自模型曲线分辨方法。文章将SIMPLISMA用于DMMP,DIMP和DEMP的IMS检测和数据的处理。这些化合物的IMS谱数据经SIMPLISMA处理后,可以提取出IMS的谱特征,并去除大部分噪声的影响。经SIMPLISMA提取的IMS谱可被用于其他计算,如曲线分辨和模式识别等。

关键词：离子淌度谱 SIMPLISMA 化学计量学数据处理甲基瞵酸酯

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U7 snRNAs:A Computational Survey

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Genomics, Proteomics & bioinformatics 2007年第3期5卷 187-195页

作者： Manja Marz Axel Mosig brbel M.R.Stadler peter F.Stadler bioinformatics Group Department of Computer ScienceUniversity of LeipzigLeipzig D-04107Germany Department of Combinatorics and Geometry CAS/MPG Partner Institute for Computational BiologyShang-hai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China Max Planck Institute for Mathematics in the SciencesLeipzig D-04103Germany Max Planck Institute for Mathematics in the Sciences Leipzig D-04103Germany bioinformatics Group Department of Computer ScienceUniversity of LeipzigLeipzig D-04107Germany Interdisciplinary Center for Bioin-formaticsUniversity of LeipzigLeipzig D-04107Germany Fraunhofer Institute for Cell Therapy and Im-munologyLeipzig D-04103Germany Department of Theoretical ChemistryUniversity of ViennaVienna A-1090Austria Santa Fe InstituteSanta FeNM 87501USA.

U7 small nuclear RNA （snRNA） sequences have been described only for a handful of animal species in the past. Here we describe a computational search for functional U7 snRNA genes throughout vertebrates including the upstream sequence elements characteristic for snRNAs transcribed by polymerase Ⅱ. based on the results of this search, we discuss the high variability of U7 snRNAs in both sequence and structure, and report on an attempt to find U7 snRNA sequences in basal deuterostomes and non-drosophilids insect genomes based on a combination of sequence, structure, and promoter features. Due to the extremely short sequence and the high variability in both sequence and structure, no unambiguous candidates were found. These results cast doubt on putative U7 homologs in even more distant organisms that are reported in the most recent release of the Rfam database.

关键词： U7 snRNA non-coding RNA RNA secondary structure evolution

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Secondary sclerosing cholangitis in a young COVID-19 patient resulting in death:A case report

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World Journal of Gastrointestinal Surgery 2022年第12期14卷 1411-1417页

作者： Jakob Steiner Ann-Katrin Kaufmann-bühler Michael Fuchsjäger peter Schemmer Emina Talakić Department of General Radiology Medical University of GrazGraz 8036Austria Department of General Visceral and Transplant Surgery Medical University of GrazGraz 8036Austria

bACKGROUND With the emergence of severe acute respiratory syndrome coronavirus 2(SARSCoV-2) in late 2019 in Wuhan, China, liver injury in patients with coronavirus disease 2019(COVID-19) due to SARS-CoV-2 infection has been regularly reported in the literature. There are a growing number of publications describing the occurrence of secondary sclerosing cholangitis(SSC) after SARS-CoV-2 infection in various cases. We present a case of sudden onset SSC in a critically ill patient(SSC-CIP) following COVID-19 infection who was previously *** SUMMARY A 33-year old female patient was admitted to our University Hospital due to increasing shortness of breath. A prior rapid antigen test showed a positive result for SARS-CoV-2. The patient had no known preexisting conditions. With rapidly increasing severe hypoxemia she required endotracheal intubation and developed the need for veno-venous extracorporeal membrane oxygenation in a setting of acute respiratory distress syndrome. During the patient’s 154-d stay in the intensive care unit and other hospital wards she underwent hemodialysis and extended polypharmaceutical treatment. With increasing liver enzymes and the development of signs of cholangiopathy on magnetic resonance cholangiopancreatography(MRCP) as well as endoscopic retrograde cholangiopancreatography(ERCP), the clinical setting was suggestive of SSC. At an interdisciplinary meeting, the possibility of orthotopic liver transplantation and additional kidney transplantation was discussed due to the constant need for hemodialysis. Following a deterioration in her general health and impaired respiratory function with a reduced chance of successful surgery and rehabilitation, the plan for transplantation was discarded. The patient passed away due to multiorgan *** SSC-CIP seems to be a rare but serious complication in patients with SARS-CoV-2 infection, of which treating physicians should be aware. Imaging with MRCP and/or ERCP seems to be indic

关键词： Secondary sclerosing cholangitis COVID-19 Liver failure Critically ill patients Magnetic resonance cholangiopancreatography Endoscopic retrograde cholangiopancreatography Case report

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