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Upper range limit establishment after wildfire of an obligateseeding montane forest tree fails to keep pace with 20th century warming

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Journal of Plant Ecology 2018年第2期11卷 200-207页

作者： john W.morgan James D.Vincent James S.Camac Research Centre for Applied Alpine Ecology Department of EcologyEnvironment and EvolutionLa Trobe UniversityKingsbury DriveBundooraVIC 3086Australia Department of Biological Sciences Macquarie UniversityBalaclava RoadNorth RydeNew South Wales 2109Australia

Aims How species respond to climate change at local scales will depend on how edaphic and biological characteristics interact with species physiological limits and traits such as *** seeders,those species that depend on fire for recruitment,have few and epi-sodic opportunities to track a changing climate *** such cases,long-distance seed dispersal will be necessary to take advan-tage of rare recruitment *** examine recruitment patterns and seedling growth below,at and above the timberline of an obligate-seeding Australian montane forest tree(Eucalyptus delegatensis)after stand-replacing fire,and place these changes in the context of regional *** We use two methods to detect whether *** can estab-lish and persist above the timberline after stand-replacing wildfire in montane forests in south-east ***,we examine estab-lishment patterns by using belt transects at six sites to quantify how changes in post-fire recruit density with increasing distance above the timberline seven years ***,to determine whether dispersal or physiological constraints determine post-fire establish-ment patterns,we transplanted seedlings and saplings into bare ground above(100 m elevation),at,and below(50 m elevation)timberline 18-months after *** monitored seedling growth and survival for one growing *** Findings There was minimal upslope migration of the species after fire with most saplings observed near seed-bearing timberline trees,with only occasional outpost *** seedlings and saplings sur-vived equally well across one growing season when planted above existing timberlines,relative to saplings at or below the *** and sapling growth rates also did not differ across these location,although seedlings grew at much faster rates than *** findings suggest that upslope growing season conditions are unlikely to limit initial range expansion of trees aft

关键词： climate change dispersal limitation growth rates regeneration niche timberline

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Two-way communication: Volatile emission and uptake occur through the same barriers

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Molecular Plant 2023年第1期16卷 1-3页

作者： Joshua R.Widhalm Meng-Ling Shih john A.morgan Natalia Dudareva Department of Horticulture and Landscape Architecture Purdue UniversityWest LafayetteIN 47907USA Center for Plant Biology Purdue UniversityWest LafayetteIN 47907USA avidson School of Chemical Engineering Purdue UniversityWest LafayetteIN 47907USA Department of Biochemistry Purdue UniversityWest LafayetteIN 47907USA

Volatile organic compounds(VOCs)are released from aboveground organs into the atmosphere and/or from roots into the soil,allowing plants to communicate and interact with their environment,including with each ***-plant communication via VOCs includes intra-and inter-species signaling as well as within-plant *** some recipient tissues,for example,VOC perception encompasses storing the modified VOC for direct defense against herbivores(Sugimoto et al.,2014)or increasing tolerance to abiotic stresses(Zhao et al.,2020).In addition,or alternatively,perceived VOCs may initiate signaling cascades that prime plant defenses(Brosset and Blande,2022).In all cases,plant VOCs are first released into the environment before being taken up and perceived by the same or neighboring *** significant progress has been made over the last several years to elucidate how VOCs are released from plant cells,these studies have also revealed new questions about how communicated VOCs are imported across cellular *** reviews(Loreto and D’Auria,2022;Wang and Erb,2022)and a special issue(Vlot and Rosenkranz,2022)have proposed mechanisms for VOC perception and *** this Opinion piece,we shed light on the gaps in knowledge about VOC import and offer perspectives for future research aiming at understanding the molecular mechanisms underlying VOC-mediated communication in plants.

关键词： communicate soil barriers

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Vasectomy by epithelial curettage without suture or cautery： a pilot study in humans

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Asian Journal of Andrology 2010年第3期12卷 315-321,I0008页

作者： john K. Amory john W. Jessen Charles Muller richard E. Berger Department of Medicine Center for Research in Reproduction and Contraception University of Washington School of Medicine Seattle WA 98195 USA private Practice Dentistry Seattle WA 98195 USA Department of Urology University of Washington School of Medicine Seattle WA 98195 USA

Curettage of the epithelium of the vas deferens might be a safe and effective method of male sterilization. We conducted a pilot study of vasectomy by epithelial curettage with a novel microcurette called the Vas-X in 12 normal men requesting elective sterilization. Seminal fluid analysis was obtained monthly after the procedure for 6 months. Pain was assessed by questionnaire. Three months after the procedure, all men attained sperm concentrations of less than 0.2 million sperm per mL, and seven were azoospermic. Post-procedural pain was minimal. Nine men ultimately achieved and maintained azoospermia; however, 4 to 6 months after the procedure, sperm concentrations increased in three of the 12 subjects, necessitating repeat vasectomy. Microscopic examination of the vas deferens from these failures revealed re-canalization. Vasectomy by epithelial curettage can result in effective sterilization; however, 1/4 of the subjects were not effectively sterilized by the procedure due to re-canalization of the vas deferens. Epithelial curettage will require further refinement to determine if it is a viable form of vasectomy.

关键词： male contraception male sterilization re-canalization spermatogenesis vas deferens vasectomy failure

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Genetic Disposition: Susceptibility of Human Blood Groups and Abo Analysis to Malaria and Typhoid Infections

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Advances in Infectious Diseases 2024年第3期14卷 497-510页

作者： Mbeh Ubana Eteng Ekpe Onot Okon Nyakno Akpan Essien Ugochukwu Iloh Godwin Oju Igile Patrick Ubi Esukwu richard Undigweundeye Ukpanukpong Ubong Edet Akpan Adaeze Bobchile-Agada Etim Esin Etim john Ojuwu Ojowu Nnennaya Precious Akpa-Onyeabor Ayiku Audu Fanziya Mary Joan Obianuju Ngumah Mcvain Akpam Ugor Department of Biochemistry Faculty of Basic Medical Sciences College of Medical Sciences University of Calabar Calabar Nigeria Department of Biochemistry Faculty of Science Imo State University Owerri Nigeria Department of Biochemistry College of Biological Sciences Federal University of Agriculture Makurdi (JOSTRUM) Benue Nigeria School of Applied Sciences Department of Science Laboratory Technology Federal Polytechnic Wannue Benue State Benue Nigeria School of Applied Sciences and Technology College of Agriculture Science and Technology Lafia Nasarawa Nigeria Department of Biology Alvan Ikoku University of Education Owerri Nigeria

Background: Malaria and typhoid have remained major infectious tropical diseases. Clinically, whenever there is severe malaria, cough is always an associating symptom owing to typhoid infection arising from poor hygiene in respect to drinking water and food. There is a strong association between human blood group and disease. Residual malaria transmission, effect of climate change on malaria vector composition, environmental management targeted at malaria breeding control as an intervention strategy are areas of interest to WHO in malaria control in Sub-saharan Africa. A body of data is been built on susceptibility of human blood groups to malaria, HIV and HBV and presently malaria and typhoid. If climate change warrants a change in composition of vectors and as well resistance to ACT therapy, the susceptibility or vulnerability of the human blood group is also called to question. The link between susceptibility of human blood group to malaria and typhoid has not been previously investigated. Purpose: The present study assesses the genetic disposition (susceptibility of human blood groups and abo analysis) to malaria and typhoid infections. Patients and Methods: One hundred (100) patients were screened for malaria and typhoid infections in a tertiary health facility—His glory hospital Lagos, Nigeria. Blood samples were collected by venu-puncture from 53 females and 47 males adults aged between 15 – 47 years, who were infected either singly or coinfected with malaria and typhoid. Microscopic detection of P. falciparum, widal serological technique for salmonella antibody presence and genotypic determination were all done using standard WHO methods. Human material or data were analyzed or performed in accordance with the declaration of Helsinki (2000). Ethical clearance was obtained from the ethic and research committee of the Ministry of Health via the Faculty of the Basic Medical Sciences, University of Calabar (Ethical Certificate number CRS/MOH/HRP/2023/396). Resul

关键词： Malaria Plasmodium Falciparium Genotype Genetig Disposition

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The Man Who Organized Nature: The Life of Linnaeus by Gunnar Broberg

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昆虫分类学报(英文) 2023年第3期45卷 239-240页

作者： john richard Schrock Division of Biology Emporia State University1200 CommercialEmporiaKansas

GunnarBroberg(1942–2022),a professor of history ideas and sciences at the Lund University in Sweden,has assembled and summarized virtually all of the contemporary documents relating to the life of Carl Linnaeus(1707–1778).This is therefore a fact-laden and definitive personal biography of the founder of our systems of plant and animal ***’childhood included much time in nature that forever provided him an experience background for the huge amount of plant and animal species he would *** his early days,his country was in an era of poverty where“hordes of starving,homeless people drifted along the roads in the years when the harvest failed.”Linnaeus himself“...could lie awake all night as he lacked the money for evening meals when he was a student.”He inserted paper into his shoes to cover the holes on which he walked.

关键词： money himself Nature

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Optical DE/MUX Components for Datacomunication Applications

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光学学报 2003年第S1期23卷 617-618页

作者： Ian H White richard V Penty Kevin A Williams Chris N morgan Cambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UKCambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UKCambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UKCambridge University Engineering Department Trumpington Street Cambridge CB2 1PZ UK

This paper reviews the potential for WDM systems to be implemented within datacommunication systems, and indicates future network functions. Spectral and temporal multiplexing functions are reviewed, with particular f... 详细信息

关键词： for be in Optical DE/MUX Components for Datacomunication Applications WDM

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When Students Become“Prisoners”:A Game Theory Analysis of Internship by Beijing College Students

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ECNU Review of Education 2018年第2期1卷 44-73页

作者： Xiaohao Ding Wei Ha Le Kang W.john morgan Graduate School of Education Peking University Cardiff University

Purpose-The oversupply of college graduates and increasing competition in the Chinese urban labor market have forced college students to undertake internships much earlier and to a greater intensity in the hope of boosting their employment *** may be argued that the considerable time and energy thus spent on internships is deleterious to their university *** paper considers the factors that determine the intensity of an internship ***/Approach/Methods-Building on a Cobb-Douglas utility function,the paper constructs a Prisoners’Dilemma game to model the internship behavior of Chinese college students,and then examines the determinants of internship using data from a 2011 survey of approximately 10,000 Chinese college students from 47 higher education institutions in the Beijing metropolitan area and multivariate regression ***-Empirical results confirm three key hypotheses derived from our model:first,students’perceptions of higher differentials across available jobs in the labor market entice them to intern excessively;second,the improving quality of college teaching and the consequent benefit for knowledge acquisition mitigates the need for excessive internship;third,student preferences for fundamental knowledge acquisition also tilts the balance towards more study and less ***/Value-These findings suggest that in the context of a tight graduate labor market,improving the quality of college teaching provides a viable alternative to excessive internship by students.

关键词： Prisoners’dilemma game theory Cobb-Douglas utility function college student internship

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Wafer-scale quasi-layered tungstate-doped polypyrrole film with high volumetric capacitance

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Nano Research 2023年第4期16卷 4895-4900页

作者： Huabo Liu Jiaxing Liang john Watt richard D.Tilley Rose Amal Da-Wei Wang School of Chemical Engineering University of New South WalesSydneyNSW 2052Australia 2 Center for Integrated NanotechnologiesLos Alamos National LaboratoryLos AlamosNW 87545USA 3 School of ChemistryUniversity of New South WalesSydneyNSW 2052Australia

Layered materials are particularly attractive for supercapacitors because of their unique physical,electrical and chemical ***,we demonstrate a facile and scalable electrochemical deposition method for wafer-scale synthesis of quasilayered tungstate-doped polypyrrole films(named TALPy)with controllable thickness and *** as-prepared TALPy film exhibits a high gravimetric density and excellent volumetric capacitance,exceeding many high-performing carbon-and polymerbased film *** on combined results of ex-situ X-ray diffraction(XRD),Raman and X-ray photoelectron spectroscopy(XPS),it is determined that TALPy stores charge through an ion intercalation process accompanied by change in oxidation states of polypyrrole backbone,which is referred as intercalation *** these results suggest the great promise of electrochemical deposition as a scalable and controllable bottom-up approach for synthesizing quasi-layered conductive organic-inorganic hybrid films for electrochemical energy storage applications with high volumetric performance.

关键词： electrochemical deposition conductive polymer polypyrrole organic-inorganic hybrid supercapacitor intercalation pseudocapacitance

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China Scholars issue Personal Invitation to British Youth

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海外华文教育动态 2011年第12期 135-136页

作者： By john morgan

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Polarization variability arising from clumps in the winds of Wolf-Rayet stars

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Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 558-576页

作者： Qing-Kang Li Joseph E Cassinelli john C. Brown richard Ignace Department of Astronomy Beijing Normal University Beijing 100875 China Department of Astronomy University of Wisconsin-Madison 53711 USA Department of Physics and Astronomy University of Glasgow Glasgow G12 8QQ Scotland UK Department of Physics and Astronomy Eastern Tennessee State University USA

Polarimetric and photometric variability of Wolf-Rayet （WR） stars as caused by clumps in the winds is revisited. In our model, which is improved from Li et al., radial expansion of the thickness is accounted for, but we retain dependence on the β velocity law and stellar occultation effects. We again search for parameters that can yield results consistent with observations in regards to the mean polarization p, the ratio R = σp/σphot of polarimetric to photometric variability and the volume filling factor fV. Clump generation and spatial distribution are randomized by the Monte Carlo method so as to produce clumps which are, in the mean, distributed uniformly in space and have time intervals that obey a Gaussian distribution. The generated clumps move radially outward with a velocity law determined by a β index, and the angular size of clumps is assumed to be fixed. By fitting the observed σp/σphot and the volume filling factor fv, clump velocity taw index β （- 2） and clump ejection rate .N （- 1） are inferred, and are found to be well constrained. In addition, the subpeak features of broad emission lines seem to support the clump ejection rate. Meanwhile, the fraction of total mass loss rate that is contained in clumps is obtained by fitting observed polarization. We conclude that this picture of the clumps＇ properties produces a valuable diagnostic of WR wind structure.

关键词： stars mass loss -- stars Wolf-Rayet -- stars winds, outflows

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