检索结果-南通市图书馆

Tomato Ovary-to-Fruit Transition is Characterized by a Spatial Shift of mRNAs for Cell Wall Invertase and its Inhibitor with the Encoded Proteins Localized to Sieve Elements

引用

molecular Plant 2015年第2期8卷 315-328页

作者： william m. Palmer School of Environmental and Life Sciences The University of Newcastle NSW 2308 Callaghan Australia Australia-China Research Centre for Crop Improvement The University of Newcastle NSW 2308 Callaghan Australia Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 300 Fenglin Road Shanghai 200032 China These authors contributed equally to the article. Present address: College of Life Sciences. Central China Normal University Wuhan 430079 China

Central to understanding fruit development is to elucidate the processes mediating a successful transition from pre-pollination ovaries to newly set fruit, a key step in establishing fruit yield potential. In tomato, cell wall invertase （CWIN） LIN5 and its inhibitor INH1 are essential for fruit growth. However, the molecular and cellular basis by which they exert their roles in ovary-to-fruit transition remains unknown. To address this issue, we conducted a study focusing on ovaries and fruitlets at 2 days before and 2 days after anthesis, respectively. In situ hybridization analyses revealed that LIN5 and INH1 exhibited a dispersed expression in ovaries compared with their phloem-specific expression in fruitlets. Remarkably, LIN5 and INH1 proteins were immunologically co-localized to cell walls of sieve elements （SEs） in ovaries immediately prior to anthesis and in young fruitlets, but were undetectable in provascular bundles of younger ovaries. A burst in CWlN activity occurred during ovary-to-fruit transition. Interestingly, the ovaries, but not the fruit- lets, exhibited high expression of a defective invertase, SldeCWIN1, an ortholog of which is known to enhance inhibition of INH on CWlN activity in tobacco. Imaging of a fluorescent symplasmic tracer indicated an apoplasmic phloem unloading pathway operated in ovaries, contrary to the previously observed symplasmic unloading pathway in fruit pericarp. These new data indicate that （1） a phloem-specific patterning of the CWIN and INH mRNAs is induced during ovary-to-fruit transition, and （2） LIN5 protein functions specifically in walls of SEs and increases its activity during ovary-to-fruit transition, probably to facilitate phloem unloading and to generate a glucose signal positively regulating cell division, hence fruit set.

关键词： fruit set invertase invertase inhibitor phloem unloading sugar signaling

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

An Overview of mODIS Radiometric Calibration and Characterization

引用

Advances in Atmospheric Sciences 2006年第1期23卷 69-79页

作者： Xiaoxiong XIONG william BARNES Earth Sciences Directorate NASA/Goddard Space Flight Center Greenbelt MD 20771 USA University of maryland Baltimore County Baltimore MD 21250 USA

The moderate Resolution Imaging Spectroradiometer （mODIS） is one of the key instruments for NASA＇s Earth Observing System （EOS）, currently operating on both the Terra and Aqua satellites. The mODIS is a major advance over the previous generation of sensors in terms of its spectral, spatial, and temporal resolutions. It has 36 spectral bands： 20 reflective solar bands （RSB） with center wavelengths from 0.41 to 2.1 μm and 16 thermal emissive bands （TEB） with center wavelengths from 3.7 to 14.4 μm, making observations at three spatial resolutions： 250 m （bands 1-2）, 500 m （bands 3-7）, and lkm （bands 8-36）. mODIS is a cross-track scanning radiometer with a wide field-of-view, providing a complete global coverage of the Earth in less than 2 days. Both Terra and Aqua mODIS went through extensive pre-launch calibration and characterization at various levels. In orbit, the calibration and characterization tasks are performed using its on-board calibrators （OBCs） that include a solar diffuser （SD） and a solar diffuser stability monitor （SDSm）, a v-grooved flat panel blackbody （BB）, and a spectro-radiometric calibration assembly （SRCA）. In this paper, we present an overview of mODIS calibration and characterization activities, methodologies, and lessons learned from pre-launch characterization and in-orbit operation. Key issues discussed in this paper include in-orbit efforts of monitoring the noise characteristics of the detectors, tracking the solar diffuser and optics degradations, and updating the sensor＇s response versus scan angle. The experiences and lessons learned through mODIS have played and will continue to play major roles in the design and characterization of future sensors.

关键词： EOS remote sensing Terra Aqua mODIS sensor calibration radiometry

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

Best Constants for moser-Trudinger Inequalities,Fundamental Solutions and One-Parameter Representation Formulas on Groups of Heisenberg Type

引用

Acta mathematica Sinica,English Series 2002年第2期18卷 375-390页

作者： COHN william S. Department of mathematics.Wayne State University.Detroit.mI 48202 USA

We derive the explicit fundamental solutions for a class of degenerate(or singular)one- parameter subelliptic differential operators on groups of Heisenberg(H)*** extends the result of Kaplan for the sub-Laplacian on H-type groups,which in turn generalizes Folland's result on the Heisenberg *** an application,we obtain a one-parameter representation formula for Sobolev functions of compact support on H-type *** choosing the parameter equal to the homogeneous dimension Q and using the mose-Trudinger inequality for the convolutional type operator on stratified groups obtained in[18].we get the following theorem which gives the best constant for the moser- Trudiuger inequality for Sobolev functions on H-type groups. Let G be any group of Heisenberg type whose Lie algebra is generated by m left invariant vector fields and with a q-dimensional *** Q=m+2q.Q'=Q-1/Q and Then. with A_Q as the sharp constant,where ▽G denotes the subelliptic gradient on G. This continues the research originated in our earlier study of the best constants in moser-Trudinger inequalities and fundamental solutions for one-parameter subelliptic operators on the Heisenberg group [18].

关键词： Heisenberg group Groups of Heisenberg type Sobolev inequalities moser-Trudinger inequalities Best constants One-Parameter representation formulas Fundamental solutions

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

Increased Drying Rate Lowers the Critical Water Content for Survival in Embryonic Axes of English Oak (Quercus robur L.) Seeds

引用

Journal of Integrative Plant Biology 2011年第4期53卷 270-280页

作者： Tobias m.Ntuli william E.Finch-Savage Patricia Berjak Norman W.Pammenter Plant Germplasm Conservation Research School of Biological and Conservation SciencesUniversity of KwaZulu-NatalWestville CampusPrivate Bag X54001Durban 4000South Africa Department of Life and Consumer Sciences University of South AfricaPrivate Bag X6Florida 1710JohannesburgSouth Africa Warwick HRI Warwick UniversityWellesbourneWarwick CV35 9EFUK Plant Germplasm Conservation Research School of Biological and Conservation SciencesUniversity of KwaZulu-NatalWestville

The potential to cryopreserve embryonic axes of desiccation-sensitive（recalcitrant） seeds is limited by damage during the desiccation necessary for low temperature survival,but the basis of this injury and how to reduce it is not well *** effects of drying rate on the viability,respiratory metabolism and free radical-mediated processes were therefore investigated during dehydration of Quercus robur L embryonic ***,assessed by evidence of germination and tetrazolium staining,showed a sharp decline at 0.27 and 0.8 g/g during rapid（〈12 h） or slow（3d） dehydration,*** dehydration therefore lowered the critical water content for *** any given water content rapid dehydration was associated with higher activities of the free radical processing enzymes,superoxide dismutase,catalase and glutathione reductase and lower levels of hydroperoxide and membrane *** dehydration was also associated with lower malate dehydrogenase activity,and a reduced decline in phosphofructokinase activity and in levels of the oxidized form of nicotinamide *** may have contributed to increased damage during slow dehydration,since viability declined even in hydrated storage after 3 *** results presented are consistent with rapid dehydration reducing the accumulation of damage resulting from desiccation induced aqueous-based deleterious reactions.

关键词： Quercus robur L Seeds Figure NADH

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

Field cancerization in the colon:a role for aberrant DNA methylation?

引用

Gastroenterology Report 2014年第1期2卷 16-20页

作者： Yanxin Luo ming Yu william m.Grady Department of Colorectal Surgery The Sixth Affiliated HospitalSun Yat-Sen UniversityGuangzhouP.R.China Gastrointestinal Institute Sun Yat-Sen UniversityGuangzhouP.R.China Clinical Research Division Fred Hutchinson Cancer Research CenterSeattleWAUSA Department of medicine University of Washington School of MedicineSeattleWAUSA

Colorectal cancer is the third most common cancer worldwide and arises secondary to the progressive accumulation of genetic and epigenetic alterations in normal colon cells,which results in a polyp-to-cancer progression *** is known that individuals with a personal history of colon adenomas or cancer are at increased risk for metachronous colon *** explanation for this increased risk could be field cancerization,which is a phenomenon in which the histologically normal tissue in an organ is primed to undergo *** alterations appear to be promising markers for field *** this review,we discuss field cancerization in the colon and the data supporting the use of methylated DNA as a biomarker for this phenomenon.

关键词： colorectal cancer field cancerization epigenetic alterations DNA methylation

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

Advancements in prokaryotic systematics and the role of Bergey's International Society for microbial Systematics in addressing challenges in the meta-data era

引用

National Science Review 2024年第07期11卷 292-304页

作者： Jian-Yu Jiao Rashidin Abdugheni Dao-Feng Zhang Iftikhar Ahmed mukhtiar Ali maria Chuvochina Svetlana N.Dedysh Xiuzhu Dong markus G?ker Brian P.Hedlund Philip Hugenholtz Kamlesh Jangid Shuang-Jiang Liu Edward R.B.moore manik Prabhu Narsing Rao Aharon Oren Ramon Rossello-mora Bhagwan Narayan Rekadwad Nimaichand Salam Wensheng Shu Iain C.Sutcliffe Wee Fei Aaron Teo martha E.Trujillo Stephanus N.Venter william B.Whitman Guoping Zhao Wen-Jun Li State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) School of Life Sciences Sun Yat-Sen University State Key Laboratory of Desert and Oasis Ecology Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsXinjiang Institute of Ecology and Geography Chinese Academy of Sciences Jiangsu Province Engineering Research Center for marine Bio-resources Sustainable Utilization&College of Oceanography Hohai University National Culture Collection of Pakistan(NCCP) Land Resources Research Institute(LRRI) National Agricultural Research Centre(NARC) The University of Queensland School of Chemistry and Molecular Biosciences Australian Centre for Ecogenomics Winogradsky Institute of microbiology Research Center of BiotechnologyRussian Academy of Sciences State Key Laboratory of microbial Resources Institute of Microbiology Chinese Academy of Sciences Leibniz Institute DSmZ–German Collection of microorganisms and Cell Cultures School of Life Sciences University of Nevada Nevada Institute of Personalized medicine University of Nevada Bioenergy Group MACS Collection of Microorganisms Agharkar Research Institute State Key Laboratory of microbial Technology Shandong University Department of Infectious Disease Institute for Biomedicine and Culture Collection University of Gothenburg(CCUG) Institute for BiomedicineSahlgrenska AcademyUniversity of Gothenburg Instituto de Ciencias Aplicadas Facultad de Ingeniería Universidad Autónoma de Chile The Alexander Silberman Institute of Life Sciences The Edmond J.Safra Campus The Hebrew University of Jerusalem marine microbiology Group Department of Animal and Microbial Biodiversity Mediterranean Institute for Advanced Studies(IMEDEA CSIC-UIB) microbeAI Lab Division of Microbiology and Biotechnology Yenepoya Research Centre Yenepoya(Deemed to be University) National Agri-Food Biotechnology Institute Institute of Ecological Science Sch

Prokaryotes are ubiquitous in the biosphere, important for human health and drive diverse biological and environmental processes. Systematics of prokaryotes, whose origins can be traced to the discovery of microorganisms in the 17th century, has transitioned from a phenotype-based classification to a more comprehensive polyphasic taxonomy and eventually to the current genome-based taxonomic *** transition aligns with a foundational shift from studies focused on phenotypic traits that have limited comparative value to those using genome sequences. In this context, Bergey's manual of Systematics of Archaea and Bacteria(BmSAB) and Bergey's International Society for microbial Systematics(BISmiS) play a pivotal role in guiding prokaryotic systematics. This review focuses on the historical development of prokaryotic systematics with a focus on the roles of BmSAB and BISmiS. We also explore significant contributions and achievements by microbiologists, highlight the latest progress in the field and anticipate challenges and opportunities within prokaryotic systematics. Additionally, we outline five focal points of BISmiS that are aimed at addressing these challenges. In conclusion, our collaborative effort seeks to enhance ongoing advancements in prokaryotic systematics, ensuring its continued relevance and innovative characters in the contemporary landscape of genomics and bioinformatics.

关键词： prokaryotic systematics Bergey's manual of Systematics of Archaea and Bacteria (BmSAB) Bergey's International Society for microbial Systematics (BISmiS) meta-data era

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

The minimum Number of Attempts for a Reliable Isometric Strength Test Score

引用

Journal of Science in Sport and Exercise 2020年第1期2卷 89-95页

作者： Sunggun Jeon william m.miller minsoo Kang Xin Ye Department of Health Exercise Scienceand Recreation ManagementThe University of MississippiUniversityMS 38677-1848USA

Purpose The maximal isometric strength test is widely used in general,athletic,and clinical ***,this test has often been used without considering how many trials are needed or appropriate to obtain reliable test ***,the aim of this study was to examine the maximal isometric strength test in upper and lower body for the purpose of determining the reliability of best isometric strength score and the ideal number of trials for a reliable test *** One hundred and twelve healthy adults were assigned to four different groups(elbow flexion with the vertical and horizontal forearm positions,knee flexion,and knee extension).After familiarization,all participants performed three maxi-mal isometric voluntary contractions with the designated muscle *** reliability of best isometric strength test score was calculated using the intraclass correlation coefficients(ICC)from a one-way ANOVA *** Spearman-Brown prophecy formula was used to identify the minimum number of trials *** The reliability of the best maximal isometric strength test scores out of three trials were high(ICC=0.92 to 0.98).At least two trials of maximal isometric strength test for knee flexion and one trial for elbow flexion and knee extension would be necessary to achieve an acceptable reliability coefficient of *** addition,one trial of elbow flexion would be enough for women,but men would need two *** Our results suggest that overall,at least two trials would be necessary to test isometric strength in upper and lower body muscles in both sexes.

关键词： Reliability Isometric strength Upper and lower body Sex difference

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

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

An investigation into intermittent electrification strategies and an analysis of resulting CO_(2) emissions using a high-fidelity train model

引用

Railway Engineering Science 2021年第3期29卷 314-326页

作者： Bilal m.Abdurahman Tim Harrison Christopher P.Ward william J.B.midgley Wolfson School of mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughborough LE113TUUK

A near-term strategy to reduce emissions from rail vehicles,as a path to full electrification for maximal decarbonisation,is to partially electrify a route,with the remainder of the route requiring an additional self-powered traction *** rail vehicles are usually powered by a diesel engine when not operating on electrified track and are referred to as bi-mode *** paper analyses the benefits of discontinuous electrification compared to continuous electrification using the CO_(2)estimates from a validated high-fidelity bi-mode(diesel-electric)rail vehicle *** analysis shows that 50%discontinuous electrification provides a maximum of 54%reduction in operational CO_(2)emissions when compared to the same length of continuously electrified *** highest emissions savings occurred when leaving train stations where vehicles must accelerate quickly to line *** results were used to develop a linear regression model for fast estimation of CO_(2)emissions from diesel running and electrification *** model was able to estimate the CO_(2)emissions from a route to within 10%of that given by the high-fidelity ***,additional considerations such as cost and the embodied CO_(2)in electrification infrastructure were analysed to provide a comparison between continuous and discontinuous *** electrification can cost up to 56%less per reduction in lifetime emissions than continuous electrification and can save up to 2.3 times more lifetime CO_(2)per distance electrified.

关键词： Railway electrification CO_(2)reduction Discontinuous electrification Bi-mode rail vehicle

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

Stem cell therapy for the treatment of Leydig cell dysfunction in primary hypogonadism

引用

World Journal of Stem Cells 2016年第10期8卷 306-315页

作者： Taylor C Peak Nora m Haney william Wang Kenneth J DeLay Wayne J Hellstrom Department of Urology School of MedicineTulane University

The production of testosterone occurs within the Leydig cells of the testes. When production fails at this level from either congenital, acquired, or systemic disorders,the result is primary hypogonadism. While numerous testosterone formulations have been developed, none are yet fully capable of replicating the physiological patterns of testosterone secretion. multiple stem cell therapies to restore androgenic function of the testes are under investigation. Leydig cells derived from bone marrow, adipose tissue, umbilical cord, and the testes have shown promise for future therapy for primary hypogonadism. In particular, the discovery and utilization of a group of progenitor stem cells within the testes, known as stem Leydig cells(SLCs), has led not only to a better understanding of testicular development, but of treatment as well. When combining this with an understanding of the mechanisms that lead to Leydig cell dysfunction, researchers and physicians will be able to develop stem cell therapies that target the specific step in the steroidogenic process that is deficient. The current preclinical studies highlight the complex nature of regenerating this steroidogenic process and the problems remain unresolved. In summary, there appears to be two current directions for stem cell therapy in male primary hypogonadism. The first method involves differentiating adult Leydig cells from stem cells of various origins from bone marrow, adipose, or embryonic sources. The second method involves isolating, identifying, and transplanting stem Leydig cells into testicular tissue. Theoretically, in-vivo re-activation of SLCs in men with primary hypogonadism due to age would be another alternative method to treat hypogonadism while eliminating the need for transplantation.

关键词： Stem cell therapy Leydig cells Primary hypogonadism Stem Leydig cells Testosterone Bone marrow-derived stem cells Adipose-derived mesenchymal stem cells

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：