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Timing is everything:does early and late germination favor invasions by herbaceous alien plants?

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Journal of Plant Ecology 2018年第1期11卷 4-16页

作者： Margherita Gioria Petr Pyšek bruce A.Osborne Institute of Botany Department of Invasion EcologyThe Czech Academy of SciencesCZ-25243 PrůhoniceCzech Republic UCD School of Biology and Environmental Science University College DublinBelfieldDublin 4Ireland Department of Ecology Faculty of ScienceCharles University in PragueViničná7CZ-12844 Prague 2Czech Republic UCD Earth Institute University College DublinBelfieldDublin 4Ireland

Aims Plant invasions represent a unique opportunity to study the mechanisms underlying community assembly rules and species distribution *** a superior competitive ability has often been proposed as a major driver of successful plant invasions,its significance depends crucially on the timing of any competitive *** assess whether a mismatch in germination phenology can favor the establishment of alien species,allowing them to exploit vacant niches where competition is *** well as having important effects on the survival,growth and fitness of a species,asymmetric competition and potential soil legacies resulting from early or late germination can also impact on species ***,early or late germination comes at a cost,increases the risks of exposure to unfavorable conditions and requires an enhanced abiotic resistance if it is to lead to successful *** Findings While there are several anecdotal accounts of early and late ger-mination for invasive species,there are limited comparative data with resident species growing under natural *** evidence from grassland communities indicates that a short-term germination advantage or priority(few days/weeks)provides inva-sive species with a strong competitive advantage over native species and is a critical factor in many *** the exploitation of periods of low competition is a plausible mechanism for the suc-cessful establishment of many invasive plants,direct evidence for this strategy is still *** is particularly true with regard to the exploitation of late germination ***,long-term comparative monitoring of the germination phenology of invasive and native plants in situ is needed to assess its significance in a range of ecosystems and its impact on community dynamics.

关键词： competition germination invasive plants phenology temporal niche

Water and nutrient and energy systems in urbanizing watersheds

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Frontiers of Environmental Science & Engineering 2012年第5期6卷 596-611页

作者： Rodrigo VILLARROEL WALKER Michael bruce BECKl, Jim W. HALL Warnell School of Forestry & Natural Resources University of Georgia Athens GA 30602-2152 USA Environmental Change Institute University of Oxford Oxford University Centre for the Environment South Parks Road Oxford OXI 3QY UK

Driven by considerations of sustainability, it has become increasingly difficult over the past 15-20 years -- at least intellectually -- to separate out the water infrastructure and water metabolism of cities from their intimately inter-related nutrient and energy metabolisms. Much of the focus of this difficulty settles on the wastewater component of the city＇s water infrastructure and its associated fluxes of nutrients （N, P, C, and so on）. Indeed, notwithstanding the massive volumes of these materials flowing into and out of the city, the notion of an urban nutrient infrastructure is conspicuous by its absence. Likewise, we do not tend to discuss, or conduct research into, ＂soilshed＂ agencies, or soilshed management, or Integrated Nutrient Resources Management （as opposed to its most familiar companion, Integrated Water Resources Management, or IWRM）. The paper summarizes some of the benefits （and challenges） deriving from adopting this broader, multi-sectoral ＂systems＂ perspective on addres- sing water-nutrient-energy systems in city-watershed settings. Such a perspective resonates with the growing interest in broader policy circles in what is called the ＂water-food-energy security nexus＂. The benefits and challenges of our Multi-sectoral Systems Analysis （MSA） are illustrated through computational results from two primary case studies： Atlanta, Georgia, USA; and London, UK. Since our work is part of the International Network on Cities as Forces for Good in the Environment （CFG; see ***）, in which other case studies are currently being initiated -- for example, on Kath- mandu, Nepal we close by reflecting upon these issues of water-nutrient-energy systems in three urban settings with quite different styles and speeds of development.

关键词： cities climate change energy sector nutrientsector systems analysis resource recovery water-food-energy security

Glucocorticoids and prostate cancer treatment： friend or foe？

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Asian Journal of Andrology 2014年第3期16卷 354-358页

作者： bruce Montgomery Heather H Cheng James Drechsler Elahe A Mostaghel Department of Medicine University of Washington Seattle Seattle Cancer Care Alliance Seattle Division of Clinical Research Fred Hutchinson Cancer Research Center Seattle Washington USA.

Glucocorticoids have been used in the treatment of prostate cancer to slow disease progression, improve pain control and offset side effects of chemo- and hormonal therapy. However, they may also have the potential to drive prostate cancer growth via mutated androgen receptors or glucocorticoid receptors （GRs）. In this review we examine historical and contemporary use of glucocorticoids in the treatment of prostate cancer, review potential mechanisms by which they may inhibit or drive prostate cancer growth, and describe potential means of defining their contribution to the biology of prostate cancer.

关键词： androgen receptor dihydrotestosterone glucocorticoid receptor glucocorticoids prostate cancer steroids testosterone

Transforming nanoscale VO_(2)(B) into a scalable sodium-ion electrode

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Nano Research 2024年第10期17卷 8809-8818页

作者： Yunkai Luo Swetha Chandrasekaran Bintao Hu Randy Chen Marcus Worsley bruce Dunn Department of Materials Science and Engineering University of CaliforniaLos AngelesCA 90095USA Lawrence Livermore National Laboratory CA 94550USA

The intermittent nature of renewable energies requires highly reliable grid-level energy storage approaches.A critical consideration in developing this technology is the areal capacity which determines battery performance and influences the cost of battery *** related importance is finding new ways of developing scalable *** recent years,threedimensional(3D)printing of conductive scaffolds has emerged as an alternative to overcome the scalability limitations of commercial tape cast *** research carried out in the current study demonstrates a successful scalability pathway for nanoscale VO_(2)(B),a desirable cathode for sodium-ion batteries which has a nano-flower morphology with a crystallite size<20 *** electrodepositing VO_(2)(B)onto a graphene aerogel scaffold,we were able to achieve mass loading of over 100 mg·cm^(-2) and still possess an areal capacity of 10 mAh·cm^(-2) at a current density of 5 mA·cm^(-2).Moreover,after 1000 cycles,these electrodes retained 75% to 80% of their initial *** at high loading levels,the electrodeposited VO_(2)(B)exhibits pseudocapacitive material signatures such as a box-like voltammetry response,linear galvanostatic response,and no phase change upon *** scalability of the VO_(2)(B)electrode is demonstrated in a series of experiments which show the areal capacity to scale upon increase in both mass loading and electrode thickness,with only small changes in specific *** study establishes that nanoscale materials can be scaled up to achieve thick electrodes without compromising their electrochemical properties.

关键词： nano VO_(2)(B) sodium-ion battery scalable electrodes three-dimensional(3D)printed scaffold additive manufacturing

Analysis of the Arabidopsis Floral Proteome:Detection of over 2000 Proteins and Evidence for Posttranslational Modifications

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Journal of Integrative Plant Biology 2009年第2期51卷 207-223页

作者： Baomin Feng Lianchao Li Xiaofan Zhou bruce Stanley Hong Ma Department of Biology the Pennsylvania State University University Park PA 16802 USA proteomics and Mass Spectrometry Core Facility 003 Althouse Laboratory the Pennsylvania State University University Park PA 16802 USA The Intercollege Graduate Program in Cell and Developmental Biology the Huck Institutes of the Life Sciences the Pennsylvania State University University Park PA 16802 USA Section of Research Resources H093 the College of Medicine the Pennsylvania State University Hershey PA 17033 USA

The proteome of the Arabidopsis flower has not been extensively studied previously. Here, we report a proteomic analysis of the wild type Arabidopsis flower. Using both two-dimensional electrophoresis/mass spectrometry （2-DGEIMS） and multi-dimensional protein identification technology （MudPIT） approaches, we identified 2 446 proteins. Although a single experiment or analysis uncovered only a subset of the proteins we identified, a combination of multiple experiments and analyses facilitated the detection of a greater number of proteins. When proteins are grouped according to RNA expression levels revealed by microarray experiments, we found that proteins encoded by genes with relatively high levels of expression were detected with greater frequencies. On the other hand, at the level of the individual gene/protein, there was not a good correlation between protein spot intensity and microarray values. We also obtained strong evidence for post-translational modification from 2-DGE and MudPIT data. We detected proteins that are annotated to function in protein synthesis, folding, modification, and degradation, as well as the presence of regulatory proteins such as transcription factors and protein kinases. Finally, sequence and evolutionary analysis of genes for active methyl group metabolisms suggests that these genes are highly conserved. Our results allow the formulation of hypotheses regarding post-translational regulation of proteins in the flower, providing new understanding about Arabidopsis flower development and physiology.

关键词： Arabidopsis floral methylation multi-dimensional protein identification technology protein modification proteome.

Assessment of VIIRS 375 m active fire using tropical peatland combustion algorithm applied to Landsat-8 over Indonesia’s peatlands

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International Journal of Digital Earth 2020年第12期13卷 1695-1716页

作者： Parwati Sofan David bruce Wilfrid Schroeder Eriita Jones Jackie Marsden Scarce Resources and Circular Economy(ScaRCE) University of South AustraliaScienceTechnologyEngineering and Mathematics(STEM)Adelaide/Mawson LakesAustralia Remote Sensing Application Center of Indonesian Institute of Aeronautics and Space(LAPAN) JakartaIndonesia National Oceanic and Atmospheric Administration(NOAA) College ParkMDUSA dImagery LandgateMidlandAustralia

VIIRS 375 m active fire data(VNP14IMG),the highest spatial resolution available cost-free fire product,were assessed for representing fire in typical degraded tropical peatlands in *** results of applying the Tropical Peatland Combustion Algorithm to Landsat-8(ToPeCAl-L8)daytime imagery were utilised as the fire *** permit the comparison of non-simultaneous VNP14IMG and ToPeCAl-L8,peatland fire propagation speeds resulting from previous study using TET-1 data in Central Kalimantan’s peatlands were *** peatland fires were still within 750 m from their source over 15 h under uniform conditions,except for very large *** detection rates of nighttime VNP14IMG compared with ToPeCAl-L8 showed about 80%agreement for small fire areas(<14 ha).For fires larger than 14 ha,a dissolved 375 m buffer(cluster buffer)of VNP14IMG active fires with an integration of nighttime and daytime acquisitions,produced a probability of detection up to 90%.These results generated a recommendation for implementing cluster buffer analysis and integration of nighttime and daytime analysis of VNP14IMG data for better accuracy in fire detection for ground fire *** also demonstrate the utility of the ToPeCAl-L8 algorithm with VIIRS 375 m active fire data.

关键词： Active fire assessment VIIRS 375 m active fire(VNP14IMG) ToPeCAlLandsat-8 peatland fires

Longitudinal association of gonorrhea and bacterial vaginosis with repeat chlamydia diagnoses among U.S. Army women: A retrospective cohort analysis

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Military Medical Research 2019年第2期6卷 128-134页

作者： Christian TBautista Eyako KWurapa Warren BSateren bruce PHollingsworth Jose LSanchez Division of Health Research Lancaster UniversityLancasterUK Walter Reed Army Institute of Research Silver SpringMDUSA Senior Research Consultant WashingtonDCUSA Armed ForcesHealth Surveillance Branch Public Health DivisionDefense HealthAgencySilver SpringMDUSA.

Background: Historically, sexually transmitted infections have affected the health of the U.S. military. To determine whether gonorrhea, bacterial vaginosis, genital herpes, and trichomoniasis are predictors of repeat chlamydia diagnoses among U.S. Army women, medical data reported into the Defense Medical Surveillance System during the 2006–2012 period were ***: For all inpatient and outpatient medical records, the first and second International Classification of Diseases,version 9(ICD-9) diagnostic positions were reviewed for each chlamydia case to determine the occurrence of repeat diagnoses. The Andersen-Gill regression model, an extension of the Cox model for multiple failure-time data, was used to study associations between predictors and repeat chlamydia ***: Among 28,201 women with a first chlamydia diagnosis, 5145(18.2%), 1163(4.1%), 267(0.9%), and 88(0.3%)had one, two, three, and four or more repeat diagnoses, respectively. Overall, the incidence of repeat chlamydia was8.31 cases per 100 person-years, with a median follow-up time of 3.39 years. Gonorrhea(hazard ratio(HR)=1.58, 95%CI: 1.44–1.73) and bacterial vaginosis(HR=1.40, 95% CI: 1.09–1.79) were significant predictors for repeat *** estimated hazard ratios were attenuated, but remained significant, after controlling for age, race/ethnicity,marital status, and military rank. No significant association was found for genital herpes(HR=1.13, 95% CI: 0.55–2.29)and trichomoniasis(HR=1.43, 95% CI: 0.43–4.68).Conclusions: This large cohort study suggests that gonorrhea and bacterial vaginosis were associated with repeat chlamydia diagnoses among U.S. Army women. These findings can be used in formulating new interventions to prevent repeat chlamydia diagnoses.

关键词： Gonorrhea Bacterial vaginosis Chlamydia Sexually transmitted infection Military

Correlation between Microstructures and Yield Strength of a High Strength Enameling Steel

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Journal of Materials Science & Technology 2012年第8期28卷 737-744页

作者： Ming Jiang Xuefeng Yang Shiyan Pan bruce W.Krakauer Mingfang Zhu Jiangsu Key Laboratory for Advanced Metallic Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189China AO Smith Corporate Technology Center MilwaukeeWI53224USA

Numerical estimates of the components of yield strength of a high strength Fe-C-Mn-P-N-Si enameling steel were determined using empirical relationships between microstructure and yield strength. Results are reported for both the hot rolled （HR） and cold rolled （CR） forms before and after simulating an enamel-fire anneal （EFA）. To determine the solubilities of alloying elements, thermodynamic calculations were performed in combination with the considerations of process conditions and the element diffusivities. The results show that the main solid solution strengtheners were the elements Mn, Si, and P, while the elements C and N were nearly completely tied up as precipitates. The yield strength reduction, due to the EFA, resulted primarily from an increase in grain size and a decrease in dislocation density, and the EFA appeared to have a negligible effect on the element solubilities.

关键词： Enameling steel Enamel-fire anneal Microstructure Yield strength Thermodynamic calculation

Bioreduction of vanadium(V) in groundwater by autohydrogentrophic bacteria:Mechanisms and microorganisms

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Journal of Environmental Sciences 2015年第4期27卷 122-128页

作者： Xiaoyin Xu Siqing Xia Lijie Zhou Zhiqiang Zhang bruce E.Rittmann State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Swette Center for Environmental Biotechnology Biodesign Institute at Arizona State University Key Laboratory of Yangtze River Water Environment Ministry of Education College of Environmental Science and EngineeringTongji University

As one of the transition metals, vanadium（V）（V（V）） in trace amounts represents an essential element for normal cell growth, but becomes toxic when its concentration is above 1 mg/L. V（V） can alter cellular differentiation, gene expression, and other biochemical and metabolic phenomena. A feasible method to detoxify V（V） is to reduce it to V（IV）, which precipitates and can be readily removed from the water. The bioreduction of V（V） in a contaminated groundwater was investigated using autohydrogentrophic bacteria and hydrogen gas as the electron donor. Compared with the previous organic donors,H2 shows the advantages as an ideal electron donor, including nontoxicity and less production of excess biomass. V（V） was 95.5% removed by biochemical reduction when autohydrogentrophic bacteria and hydrogen were both present, and the reduced V（IV）precipitated, leading to total-V removal. Reduction kinetics could be described by a first-order model and were sensitive to p H and temperature, with the optimum ranges of p H 7.5–8.0 and 35–40°C, respectively. Phylogenetic analysis by clone library showed that the dominant species in the experiments with V（V） bioreduction belonged to theβ-Proteobacteria. Previously known V（V）-reducing species were absent, suggesting that V（V）reduction was carried out by novel species. Their selective enrichment during V（V）bioreduction suggests that Rhodocyclus, a denitrifying bacterium, and Clostridium, a fermenter known to carry out metal reduction, were responsible for V（V） bioreduction.

关键词： Vanadium Bioreduction Hydrogen Rhodocyclus Clostridium