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

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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

Using potential distributions to explore environmental correlates of bat species richness in southern Africa： Effects of model selection and taxonomy

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Current Zoology 2013年第3期59卷 279-293页

作者： M. Corrie SCHOEMAN f. P. D. (Woody) COTTERILL peter J. TAYLOR Ara MONADJEM School of Life Sciences University of KwaZulu-Natal Westville Campus Durban 4000 South Africa Africa Earth Observatory Network (AEON) Geoecodynamics Research Hub c/o Department of Botany and Zoology University of Stellenbosch Stellenbosch 7602 South Africa Department of Ecology and Resource Management School of Environmental Sciences University of Venda Thohoyandou 0950 South Africa All Out Africa Research Unit Department of Biological Sciences University of Swaziland Private Bag 4 Kwaluseni Swaziland Mammal Research Institute Department of Zoology & Entomology University of Pretoria Private Bag 20 Hatfield 0028 Pretoria South Africa

We tested the prediction that at coarse spatial scales, variables associated with climate, energy, and productivity hy- potheses should be better predictor（s） of bat species richness than those associated with environmental heterogeneity. Distribution ranges of 64 bat species were estimated with niche-based models informed by 3629 verified museum specimens. The influence of environmental correlates on bat richness was assessed using ordinary least squares regression （OLS）, simultaneous autoregressive models （SAR）, conditional autoregressive models （CAR）, spatial eigenvector-based filtering models （SEVM）, and Classification and Regression Trees （CART）. To test the assumption of stationarity, Geographically Weighted Regression （GWR） was used. Bat species richness was highest in the eastern parts of southern Africa, particularly in central Zimbabwe and along the western border of Mozambique. We found support for the predictions of both the habitat heterogeneity and climate/productivity/energy hypothe- ses, and as we expected, support varied among bat families and model selection. Richness patterns and predictors of Miniopteridae and Pteropodidae clearly differed from those of other bat families. Altitude range was the only independent variable that was sig- nificant in all models and it was most often the best predictor of bat richness. Standard coefficients of SAR and CAR models were similar to those of OLS models, while those of SEVM models differed. Although GWR indicated that the assumption of stationa- rity was violated, the CART analysis corroborated the findings of the curve-fitting models. Our results identify where additional data on current species ranges, and future conservation action and ecological work are needed.

关键词： Chiroptera Macroecology Niche-based models Spatial models Species richness

Peeling off the surface: Pt-decoration of WSe 2 nanoflakes results in exceptional photoelectrochemical HER activity

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SusMat 2022年第6期2卷 749-760页

作者： peter S.Toth Gabor Szabo Gabor Bencsik Gergely f.Samu Krishnan Rajeshwar Csaba Janaky Department of Physical Chemistry and Materials Science Interdisciplinary Excellence CenterUniversity of SzegedSzegedHungary Department of Chemistry and Biochemistry The University of Texas at ArlingtonArlingtonTexasUSA

Photoelectrochemical(PEC)hydrogen evolution reaction(HER)was studied on exfoliated,pristine and Pt-decorated tungsten diselenide(p-WSe_(2))nanoflake samples,using a previously developed microdroplet PEC microscopy *** WSe 2 nanoflakes had well-defined thicknesses as measured by atomic force microscopy,and the Pt nanoparticles(NPs)were deposited by a variable num-ber of atomic layer deposition(ALD)*** exceptionally high photocurrent density of 49.6 mA cm^(−2)(under 220 mW cm^(−2) irradiation)and internal-photon-to-electron-conversion efficiency(∼90%at 550 nm)were demonstrated on these Pt-decorated WSe_(2)(WSe_(2)-Pt)*** Pt NP loading and thickness of WSe_(2) nanoflakes(in the 24–235 nm range)were used to fine-tune their PEC activity for *** found similar charge transfer and surface recombination kinetics of pristine and WSe_(2)-Pt specimens(as assessed by intensity-modulated photocurrent spectroscopy),which indicated significant differences in their bulk properties.X-ray and ultraviolet photoelectron spectroscopies were performed to identify defect states and quantify the density of states around the valence band of WSe_(2).The elevated temperature of the ALD process and the evolving Pt NP phase conspired to passivate the sub-surface(i.e.,bulk)defects in the WSe_(2) nanoflakes,resulting in their vastly improved PEC performance.

关键词： atomic layer deposition defect migration density of states hydrogen evolution layered semiconductor photoelectrochemical kinetics

Upscaling and downscaling methods for environmental research

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U7 snRNAs:A Computational Survey

2000年

作者： edited by Marc f.P. Bierkens, peter A. finke and peter de Willigen.

来源：畅想之星图书光盘版（南... 评论

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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

Predictive value of multi-detector computed tomography for accurate diagnosis of serous cystadenoma:Radiologic-pathologic correlation

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World Journal of Gastroenterology 2009年第22期15卷 2739-2747页

作者： Anjuli A Shah Nisha I Sainani Avinash Kambadakone Ramesh Zarine K Shah Vikram Deshpande peter f Hahn Dushyant V Sahani Department of Radiology Division of Abdominal Imaging and Interventional RadiologyWhite Bldg.270Massachusetts General Hospital Department of Pathology Massachusetts General Hospital

AIM： To identify multi-detector computed tomography （MDCT） features most predictive of serous cystadenomas （SCAs）, correlating with histopathology, and to study the impact of cyst size and MDCT technique on reader performance. METHODS： The MDCT scans of 164 patients with surgically verified pancreatic cystic lesions were reviewed by two readers to study the predictive value of various morphological features for establishing a diagnosis of SCAs. Accuracy in lesion characterization and reader confidence were correlated with lesion size （≤3 cm or 〉≥3 cm） and scanning protocols （dedicated vs routine）. RESULTS： 28/164 cysts （mean size, 39 mm; range, 8-92 mm） were diagnosed as SCA on pathology. The MDCT features predictive of diagnosis of SCA were microcystic appearance （22/28, 78.6%）, surface Iobulations （25/28, 89.3%） and central scar （9/28, 32.4%）. Stepwise logistic regression analysis showed that only microcystic appearance was significant for CT diagnosis of SCA （P = 0.0001）. The sensitivity, specificity and PPV of central scar and of combined microcystic appearance and Iobulations were 32.4%/100%/100% and 68%/100%/100%, respectively. The reader confidence was higher for lesions 〉 3 cm （P = 0.02） and for MDCT scans performed using thin collimation （1.25-2.5 mm） compared to routine 5 mm collimation exams （P 〉 0.05）. CONCLUSION： Central scar on MDCT is diagnostic of SCA but is seen in only one third of SCAs. Microcystic morphology is the most significant CT feature in diagnosis of SCA. A combination of microcystic appearance and surface Iobulations offers accuracy comparable to central scar with higher sensitivity.

关键词： Pancreas Serous cystadenoma Multidetector computed tomography Central scar Lobulations Microcystic

from Persistent Identifiers to Digital Objects to Make Data Science More Efficient

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Data Intelligence 2019年第1期1卷 6-21页

作者： peter Wittenburg Max Planck Computing and Data facility Gießenbachstraße 285748 GarchingGermany

Data-intensive science is reality in large scientific organizations such as the Max Planck Society,but due to the inefficiency of our data practices when it comes to integrating data from different sources,many projects cannot be carried out and many researchers are *** about 80%of the time in data-intensive projects is wasted according to surveys we need to conclude that we are not fit for the challenges that will come with the billions of smart devices producing continuous streams of data-our methods do not *** experts worldwide are looking for strategies and methods that have a potential for the *** first steps have been made since there is now a wide agreement from the Research Data Alliance to the fAIR principles that data should be associated with persistent identifiers(PID)and metadata(MD).In fact after 20 years of experience we can claim that there are trustworthy PID systems already in broad *** is argued,however,that assigning PIDs is just the first *** we agree to assign PIDs and also use the PID to store important relationships such as pointing to locations where the bit sequences or different metadata can be accessed,we are close to defining Digital Objects(DOs)which could indeed indicate a solution to solve some of the basic problems in data management and *** addition to standardizing the way we assign PIDs,metadata and other state information we could also define a Digital Object Access Protocol as a universal exchange protocol for DOs stored in repositories using different data models and data *** could also associate a type with each DO and a set of operations allowed working on its content which would facilitate the way to automatic processing which has been identified as the major step for scalability in data science and data industry.A globally connected group of experts is now working on establishing testbeds for a DO-based data infrastructure.

关键词： Big data Data management Persistent identifiers Digital objects Data infrastructure Data intensive science

Multi-omic Analyses Shed Light on The Genetic Control of High-altitude Adaptation in Sheep

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 43-56页

作者： Chao Li Bingchun Chen Suo Langda Peng Pu Xiaojia Zhu Shiwei Zhou peter Kalds Ke Zhang Meenu Bhati Alexander Leonard Shuhong Huang Ran Li Awang Cuoji Xiran Wang Haolin Zhu Yujiang Wu Renqin Cuomu Ba Gui Ming Li Yutao Wang Yan Li Wenwen fang Ting Jia Tianchun Pu Xiangyu Pan Yudong Cai Chong He Liming Wang Yu Jiang Jian-Lin Han Yulin Chen Ping Zhou Hubert Pausch Xiaolong Wang International Joint Agriculture Research Center for Animal Bio-Breeding Ministry of Agriculture and Rural Affairs/Key Laboratory of Animal GeneticsBreeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China Animal Genomics ETH ZürichZürich 8092Switzerland Institute of Animal Science Tibet Academy of Agricultural and Animal Husbandry SciencesLhasa 850009China School of Biological and Pharmaceutical Engineering Lanzhou Jiaotong UniversityLanzhou 730070China College of Life Sciences Shaanxi Normal UniversityXi’an 710119China Zoology and Evolutionary Biology Department of BiologyUniversity of Konstanz78457 KonstanzGermany College of Life and Geographic Sciences Kashi UniversityKashi 844000China Beijing Key Laboratory of Captive Wildlife Technologies Beijing ZooBeijing 100044China Department of Medical Research Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural Affairs/Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent ServiceCollege of Information EngineeringNorthwest A&F UniversityYangling 712100China Institute of Animal Husbandry and Veterinary Medicine Xinjiang Academy of Agricultural and Reclamation SciencesShihezi 832000China State Key Laboratory of Sheep Genetic Improvement and Healthy Production Xinjiang Academy of Agricultural and Reclamation SciencesShihezi 832000China CAAS-ILRI Joint Laboratory on Livestock and forage Genetic Resources Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193China Livestock Genetics Program International Livestock Research InstituteNairobi 00100Kenya

Sheep were domesticated in the fertile Crescent and then spread globally,where they have been encountering various environmental *** Tibetan sheep has adapted to high altitudes on the Qinghai-Tibet Plateau over the past 3000 *** explore genomic variants associated with high-altitude adaptation in Tibetan sheep,we analyzed Illumina short-reads of 994 whole genomes representing∼60 sheep breeds/populations at varied altitudes,PacBio High fidelity(Hifi)reads of 13 breeds,and 96 transcriptomes from 12 sheep *** testing between the inhabited altitudes and 34,298,967 variants was conducted to investigate the genetic architecture of altitude *** accurate Hifi reads were used to complement the current ovine reference assembly at the most significantly associatedβ-globin locus and to validate the presence of two haplotypes A and B among 13 sheep *** haplotype A carried two homologous gene clusters:(1)HBE1,HBE2,HBB-like,and HBBC,and(2)HBE1-like,HBE2-like,HBB-like,and HBB;while the haplotype B lacked the first *** high-altitude sheep showed highly frequent or nearly fixed haplotype A,while the low-altitude sheep dominated by haplotype *** further demonstrated that sheep with haplotype A had an increased hemoglobin–O2 affinity compared with those carrying haplotype *** highly associated genomic region contained the EGLN1 gene which showed varied expression between high-altitude and low-altitude *** results provide evidence that the rapid adaptive evolution of advantageous alleles play an important role in facilitating the environmental adaptation of Tibetan sheep.

关键词： Environmental adaptation High altitude Hypoxia Selection signature Sheep

Metaphysical and Value Underpinnings of Traditional Medicine in West Africa

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Chinese Journal of Integrative Medicine 2011年第3期17卷 99-104页

作者： peter f.Omonzejele Chukwugozie Maduka Department of Philosophy University of Benin Benin CityNigeria

This study investigated the extent to which recourse to traditional healers depended on biometric variables;ways of knowing in good time what ailments were more likely to be better handled by traditional healers;rationale behind traditional healing *** the whole,four research questions were *** sample for the study included residents in urban（Benin City） and rural（Ehime Mbano） communities in *** instruments comprised of two *** traditional healers were also interviewed in *** findings of the research included the following：in both rural and urban areas,women and more elderly persons had more recourse than other groups to traditional medicine;Christians,less educated persons,self-employed persons and women affirmed most strongly to the efficacy of traditional medicine over Western medicine with respect to certain ailments;ways for averting spiritual illnesses included obeying instructions from ancestors and offering regular sacrifices to the gods;methods used by traditional healers to determine whether an ailment was ＂spiritual＂ or as a result of home problems included diagnosis linked to divination,interpretation of dreams particularly those involving visits by ancestors,interpretation of nightmares and omens such as the appearance of owls;methods for curing patients included use of herbs particularly those believed to have magical powers,offering of sacrifices,use of incantations and wearing of protective medicine.

关键词： metaphysics values spiritual home problem traditional medicine West Africa