检索结果-南通市图书馆

Aggregated seed arrival alters plant diversity in grassland communities

Journal of Plant Ecology 2014年第1期7卷 51-58页

作者： gregory R.Houseman Department of Biological Sciences Wichita State University1845 FairmountWichitaKS 67260USA

Aims Species aggregation is commonly seen in plant communities and may increase diversity by causing intraspecific competition to exceed interspecific *** potential source of this spatial aggregation is seed dispersal but it is unclear to what extent aggregated seed distributions affect plant diversity in real *** a field experiment,I tested whether uniform or aggregated seed arrival alters community structure and whether these effects vary with sowing *** The experiment consisted of two spatial seeding treatments(uniform and aggregated)that were fully crossed with three seed density ***,3×4-m plots were arrayed in a low-diversity grassland located in Kansas,*** plot was divided into fortyeight,0.5×0.5-m *** aggregated seeding treatments,each of the 15 species was sown into three randomly selected patches within the plot(3×15=45).To create a uniform species arrival but control for the seed addition method,all 15 species were sown into 45 individual patches(with three patches remaining unsown)within each *** mass for each species was held constant at the plot scale between uniform or aggregated treatments within a given level of the sowing density *** two growing seasons,plant density was quantified for all sown species in 15 randomly selected patches from each *** Findings I found evidence for shifts in community structure in response to the different spatial seeding *** evenness of added species was higher under aggregated than uniform sowing *** was no detectable effect of aggregated seed sowing on species richness at 3.75 m^(2) ***,when species richness was extrapolated to larger scales(11.25 m^(2)),aggregated sowing was predicted to have greater richness than uniform *** of seed aggregation on community structure were apparent only at moderate to high sowing rates,yet the latter are within the range of measured seed dispersal in s

关键词： clumped colonization rank-abundance distributions seed dispersal seed sowing

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Soil fertilization does not alter plant architectural effects on arthropod communities

引用

Journal of Plant Ecology 2017年第5期10卷 800-807页

作者： m.Noelia Barrios-Garcia mariano A.Rodriguez-Cabal Jennifer A.Rudgers gregory m.Crutsinger CONICET CENAC-APNFagnano 244BarilocheRio Negro CP.8400Argentina Grupo de Ecología de Invasiones INIBIOMA-CONICETUniversidad Nacional del ComahueAv.de los Pioneros 2350BarilocheRio Negro CP.8400Argentina Department of Biology University of New MexicoCastetter Hall 286AlbuquerqueNM 87131USA Department of Zoology University of British Columbia#4200-6270 University Blvd.VancouverBritish Columbia V6T 1Z4Canada

Aims While a growing number of studies have demonstrated the impor-tance of intraspecific differences within plant species on associ-ated arthropod communities,little is known regarding the relative strength of these effects compared to environmental *** this study,we examined whether intraspecific plant differences and nutrient fertilization interact to shape the arthropod community of a dominant coastal shrub,Baccharis pilularis(coyote bush).methods We overlaid a fertilization treatment on a 12-year-old common garden experiment planted with erect and prostrate architectural morphs of Baccharis in california,*** collect the associated arthropod community,we vacuum sampled the crown of each Baccharis and identified individuals to species or *** Findings We found that arthropod richness and abundance were 2-to 3-fold greater on prostrate Baccharis than on erect morphs,but observed no main effects of fertilizer addition on the over-all arthropod *** responded as strongly as herbivores to plant morph,and both were unaffected by nutrient *** the specialist stem galler,Gnorimoschema bac-charisella,showed an interactive response to plant morph and ***,phosphorous and potassium addition had opposite effects on the two morphs,increasing stem gall abun-dance by 50%on prostrate morphs,but reducing galling by 20%on erect *** architectural complexity of prostrate morphs could be the driving mechanism of differences in arthropod ***,our results demonstrate that communitylevel consequences of intraspecific differences in plants are strong,rather than being context dependent,and are generally maintained under different resource *** growing number of studies showing strong genotype than nutrient effects on associated arthropod communities suggests that this might be a generalized pattern.

关键词： Baccharis pilularis community genetics G×E interactions galling insects nutrient fertilization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Emeishan large igneous province:A synthesis

引用

Geoscience Frontiers 2014年第3期5卷 369-394页

作者： J.gregory Shellnutt National Taiwan Normal University Department of Earth Science

The late Permian Emeishan large igneous province （EL1P） covers -0.3× 10-6 kmL of the western margin of the Yangtze Block and Tibetan Plateau with displaced, correlative units in northern Vietnam （song Da zone）. The ELIP is of particular interest because it contains numerous world-class base metal deposits and is contemporaneous with the late Capitanian （-260 ma） mass extinction. The flood basalts are the signature feature of the ELIP but there are also ultramafic and silicic volcanic rocks and layered mafic- ultramafic and silicic plutonic rocks exposed. The EL1P is divided into three nearly concentric zones （i.e. inner, middle and outer） which correspond to progressively thicker crust from the inner to the outer zone. The eruptive age of the ELIP is constrained by geological, paleomagnetic and geochronological evidence to an interval of 〈3 ma. The presence of picritic rocks and thick piles of flood basalts testifies to high temperature thermal regime however there is uncertainty as to whether these magmas were derived from the subcontinental lithospheric mantle or sub-lithospheric mantle （i.e. asthenosphere or mantle plume） sources or both. The range of Sr （Isr ≈ 0.7040-0.7132）, Nd （ENd（t） ≈ -14 tO ＋8）, Pb （206-pb/204-pb1 ≈ 17.9-20.6） and Os （Yos ≈ -5 to ＋11） isotope values of the ultramafic and mafic rocks does not permit a conclusive answer to ultimate source origin of the primitive rocks but it is clear that some rocks were affected by crustal contamination and the presence of near-depleted isotope compo- sitions suggests that there is a sub-lithospheric mantle component in the system. The silicic rocks are derived by basaltic magmas/rocks through fractional crystallization or partial melting, crustal melting or by interactions between mafic and crustal melts. The formation of the Fe-Ti-V oxide-ore deposits is probably due to a combination of fractional crystallization of Ti-rich basalt and fluxing of C02-rich fluids whereas the Ni-Cu-（PGE） deposits are related

关键词： Late Permian mantle plume Large igneous province Flood basalts mineral deposits Uplift and doming

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Beyond the SDG 15.3.1 Good Practice Guidance 1.0 using the Google Earth Engine platform: developing a self-adjusting algorithm to detect significant changes in water use efficiency and net primary production

引用

Big Earth Data 2023年第1期7卷 59-80页

作者： Andrea markos Neil Sims gregory Giuliani Foundation for the Conservation of the Chiquitano Forest Santa CruzBolivia Bolivian National Academy of Sciences La PazBolivia Centre for Earth Observation Space&AstronomyCSIROClaytonAustralia GEO LDN Initiative Institute for Environmental Sciences EnviroSPACE LabUniversity of GenevaGenevaSwitzerland Institute for Environmental Sciences GRID-GenevaUniversity of GenevaGenevaSwitzerland

monitoring changes in Annual Net Primary Productivity(ANPP)is required for reporting on UN Sustainable Development Goal(SDG)Indicator 15.3.1:the proportion of land that is degraded over the total land *** time-series observations of ANPP to derive Water Use Efficiency(WUE;a measure of ANPP per unit of evapotranspiration)can minimize the influence of climate factors on ANPP observations and highlight the influence of non-climatic drivers of degradation such as land use *** the ANPP and WUE time series may be useful for identifying the primary drivers of land degradation,which could be used to support the Land Degradation Neutrality objectives of the UN Convention to Combat Desertification(UNCCD).This paper presents an algorithm for the Google Earth Engine(freely and openly available upon request-http://***/10.5281/zenodo.4429773)to calculate and compare ANPP and WUE time series for Santa Cruz,Bolivia,which has recently experienced an intensification in its land *** code builds on the Good Practice Guidance document(ver-sion 1)for monitoring SDG Indicator *** use the mODIS 16-day average,250 m resolution to demonstrate that the Enhanced Vegetation Index(EVI)responds faster to changes in water avail-ability than the Normalized Difference Vegetation Index(NDVI).We also consider the relationships between ANPP and *** and concordant trends may highlight good agricultural practices or increased resilience in ecosystem structure and productivity when they are positive or reducing resilience and functional integrity if *** sign and significance of the correlation between ANPP and WUE may also diverge over *** further analysis,it may be possible to interpret this relationship in terms of the drivers of change in plant productivity and ecosystem resilience.

关键词： Land degradation land productivity water use efficiency Google Earth Engine mODIS Good Practice Guidance SDG 15.3.1

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

modeling of Electromagnetic,Temperature,and Velocity Fields During Solidification in an Electromagnetically Stirred melt

引用

Journal of Iron and Steel Research International 2012年第S1期19卷 252-255页

作者： gregory m POOLE Nagy EL-KADDAH Department of metallurgical Engineering University of Alabama35487TuscaloosaAlabama USA

This paper describes a comprehensive model for predicting the evolution of the velocity and temperature fields in electromagnetically-driven flows during *** electromagnetic field was formulated using the mutual inductance method,which accounts for the metal,chill blocks,and magnetic *** model solves the heat transfer equation throughout the system,as well as the fluid flow equations in the liquid and mushy regions.A two-zone model for the mushy region that accounts for dampening of momentum by the turbulent field has been *** turbulence in the molten region was determined using the k-s *** were performed for unidirectional solidification in a bottom chill mold placed in a stationary magnetic *** results show that the flow field at the beginning of solidification shows typical four recirculating loops,and later evolves to two recirculating loops as solidification *** magnitude of the velocity in the bulk liquid was found to decrease as solidification progresses.

关键词： solidification electromagnetic stirring flow in bulk and mushy region turbulence

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Regression of recurrent granulosa cell tumor liver metastases following selective internal radiation therapy

引用

Hepatobiliary & Pancreatic Diseases International 2023年第4期22卷 406-408页

作者： Omar A mownah John D Leahy Jeffrey Summers Stephen m gregory Nigel D Heaton Institute of Liver Studies King’s Healthcare PartnersKing’s College Hospital NHS Foundation TrustDenmark HillLondon SE59RSUK Department of Oncology Maidstone and Tunbridge Wells NHS TrustMaidstone ME169QQUK

Granulosa cell tumor(GCT)is the most common sex cordstromal tumor,comprising 5%of all ovarian malignancies[1].The disease course is indolent,and the majority of cases present at stage ***,metastases may develop with potential sites being peritoneum,lung,brain,liver and bone[2].Due to the rarity of the disease,published evidence for management of granulosa cell tumor liver metastases(GCTLm)is *** resection is the optimal treatment in instances where there is a high chance of achieving complete resection[3].With regards to unresectable GCTLm there is a paucity of evidence to guide treatment strategy.

关键词： metastases liver lung

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Smaller and bolder prey snails have higher survival in staged encounters with the sea star Pisaster giganteus

引用

Current Zoology 2017年第6期63卷 633-638页

作者： William C. FOSTER Connor m. ARmSTRONG gregory T. CHISm Jonathan N. PRUITT Department of Ecology Evolution and Marine Biology University of California Santa Barbara Santa Barbara CA93180 USA

Temporally consistent individual differences in behavior, also known as animal personality, can have large impacts on individual fitness. Here, we explore the degree to which individual differences in anti-predator response （or boldness） influence survival rates in groups of snails Chlorostoma funebralis when they encounter a predatory sea star Pisaster giganteus. The snail C. funebralis shows consistent individual variation in predator response where some fearful snails actively flee bodies of water occupied by predators whereas bolder snails consistently do not. We show here that bold snails are significantly more likely to survive encounters with a predatory sea star and, somewhat counterintuitively, fearful snails actually suffer higher mortality rates. We also found that smaller snails and those occurring at higher experimental densities experienced higher per capita survival rates. Positive effects of prey boldness on survival are not uncommonly reported in the animal personality literature; however, such results are inconsistent with classic animal personality theory borrowed from the optimal foraging literature. The findings herein add to the growing body of evidence that consistent individual differences in behavior can impact predator-prey interactions and that boldness is potentially under positive predator-driven selection in some systems.

关键词： behavioral syndrome behavioral type predation risk personality survival selection temperament.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A method to deliver patterned electrical impulses to Schwann cells cultured on an artificial axon

引用

Neural Regeneration Research 2019年第6期14卷 1052-1059页

作者： Antonio merolli Yong mao gregory Voronin Joseph A.m.Steele N.Sanjeeva murthy Joachim Kohn New Jersey Center for Biomaterials Rutgers-The State University of New Jersey In Vivo Research Services Rutgers-The State University of New Jersey

Information from the brain travels back and forth along peripheral nerves in the form of electrical impulses generated by neurons and these impulses have repetitive patterns. Schwann cells in peripheral nerves receive molecular signals from axons to coordinate the process of myelination. There is evidence, however,that non-molecular signals play an important role in myelination in the form of patterned electrical impulses generated by neuronal activity. The role of patterned electrical impulses has been investigated in the literature using co-cultures of neurons and myelinating cells. The co-culturing method, however, prevents the uncoupling of the direct effect of patterned electrical impulses on myelinating cells from the indirect effect mediated by neurons. To uncouple these effects and focus on the direct response of Schwann cells,we developed an in vitro model where an electroconductive carbon fiber acts as an artificial axon. The fiber provides only the biophysical characteristics of an axon but does not contribute any molecular *** our "suspended wire model", the carbon fiber is suspended in a liquid media supported by a 3D printed scaffold. Patterned electrical impulses are generated by an Arduino 101 microcontroller. In this study, we describe the technology needed to set-up and eventually replicate this model. We also report on our initial in vitro tests where we were able to document the adherence and ensheath of human Schwann cells to the carbon fiber in the presence of patterned electrical impulses(hSCs were purchased from ScienCell Research Laboratories, Carlsbad, CA, USA; ScienCell fulfills the ethic requirements, including donor's consent). This technology will likely make feasible to investigate the response of Schwann cells to patterned electrical impulses in the future.

关键词： Schwann cell carbon fiber myelination electrical impulse artificial axon in vitro system Arduino microcontroller myelin basic protein

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Surgical dilemmas in the management of colorectal liver metastases: the role of timing

引用

World Journal of Gastroenterology 2016年第21期22卷 4963-4965页

作者： Dimitrios Dimitroulis gregory Kouraklis Second Department of Surgery University of Athens Medical SchoolAthens GreeceLaiko Hospital11527 AthensGreece

Colorectal cancer(CRC) is an emerging health problem in the Western World both for its raising tendency as well as for its metastatic potential. Almost half of the patients with CRC will develop liver metastases during the course of their disease. The liver surgeon dealing with colorectal liver metastases faces several surgical dilemmas especially in the setting of the timing of operation. Synchronous resectable metastases should be treated prior or after induction chemotherapy? Furthermore in the case of synchronous colorectal liver metastases which organ should we first deal with, the liver or the colon? All these questions are set in the editorial and impulse for further investigation is put focusing on multidisciplinary approach and individualization of treatment modalities.

关键词： Colorectal cancer Chemotherapy Timing of surgery Colorectal liver metastases Liver first procedure multidisciplinary approach Individualized treatment strategies

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Intra-procedural arrhythmia during cardiac catheterization: A systematic review of literature

引用

World Journal of Cardiology 2020年第6期12卷 269-284页

作者： Fatima A Shaik David J Slotwiner gregory m.gusta.son Xuming Dai Division of Cardiology New York Presbyterian Queens HospitalFlushingNY 11355United States

BACKGROUND Cardiac catheterization is among the most performed medical procedures in the modern *** were sporadic reports indicating that cardiac arrhythmias are common during cardiac catheterization,and there are risks of developing serious and potentially life-threatening arrhythmias,such as sustained ventricular tachycardia(VT),ventricular fibrillation(VF)and high-grade conduction disturbances such as complete heart block(CHB),requiring immediate ***,there is lack of systematic overview of these *** To systematically review existing literature and gain better understanding of the incidence of cardiac arrhythmias during cardiac catheterization,and their impact on outcomes,as well as potential approaches to minimize this *** We applied a combination of terms potentially used in reports describing various cardiac arrhythmias during common cardiac catheterization procedures to systematically search Pubmed,EmBASE and Cochrane databases,as well as references of full-length *** During right heart catheterization(RHC),the incidence of atrial arrhythmias(premature atrial complexes,atrial fibrillation and flutter)was low(mias were usually transient and *** associated with the development of a new RBBB at a rate of 0.1%-0.3%in individuals with normal conduction system but up to 6.3%in individuals with pre-existing left bundle branch *** patients may require temporary pacing due to transient *** premature ventricular complexes or non-sustained VT are common during RHC(up to 20%of cases).Sustained ventricular arrhythmias(VT and/or VF)requiring either withdrawal of catheter or cardioversion occurred infrequently(1%-1.3%).During left heart catheterizations(LHC),the incidence of ventricular arrhythmias has declined significantly over the last few decades,from 1.1%historically to 0.1%*** overall reported rate of VT/VF in diagnostic LHC and coronary angiography is 0.8

关键词： Catheterization Coronary angiography Percutaneous coronary intervention Ventricular fibrillation Ventricular tachycardia

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：