检索结果-南通市图书馆

Thermodynamic contributions of 5’- and 3’-single strand dangling-ends to the stability of short duplex DNAs

j.urnal of Biophysical Chemistry 2012年第1期3卷 1-15页

作者： Rebekah Dickman Fidelis Manyanga Greg P. Brewood daniel j. fish Cameron A. fish Charlie Summers M. Todd Horne Albert S. Benight Portland Bioscience Inc. Portland USA

Differential scanning calorimetry (DSC) melting analysis was performed on 27 short double stranded DNA duplexes containing 15 to 25 base pairs. Experimental duplexes were divided into two categories containing either two 5’ dangling-ends or one 5’ and one 3’ dangling-end. Duplex regions were incrementally reduced from 25 to 15 base pairs with a concurrent increase in length of dangling-ends from 1 to 10 bases. Blunt-ended duplexes from 15 to 25 base pairs served as controls. An additional set of molecules containing 21 base pair duplexes and a single four base dangling-end were also examined. DSC melting curves were measured in varying concentrations of sodium ion (Na+). From these measurements, thermodynamic parameters for 5’ and 3’ dangling-ends were evaluated as a function of dangling end length. 5’ ends were found to be slightly stabilizing but essentially constant while the 3’ ends were destabilizing with increasing length of the dangling-end. 3’ ends also display a stronger dependence on Na+ concentration. In lower Na+ environment, the 3’ ends were more destabilizing than in higher salt environment suggesting a more significant electrostatic component of the destabilizing interactions. Analysis of thermodynamic parameters of dangling ended duplexes as a function of Na+ concentration indicated the 3' dangling ends behave differently than 5' dangling ended and blunt-ended duplexes. Molecules with one 5' and one 3' dangling end showed variation in excess specific heat capacity (ΔCp) when compared to the blunt-ended molecule, while the molecules with two 5’ ends had ΔCp values that were essentially the same as blunt-ended duplexes. These observations suggested differences exist in duplexes with 3’ and 5’ dangling ends, which are interpreted in terms of composite differences in interactions with Na+, solvent, and terminal base pairs of the duplex.

关键词： DNA Thermodynamics Dangling-Ends DNA Stability

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

Effects of Selective Biotinylation on the Thermodynamic Stability of Human Serum Albumin

引用

j.urnal of Biophysical Chemistry 2016年第1期7卷 9-29页

作者： Huyen Hoang Fidelis Manyanga Moshood K. Morakinyo Vincent Pinkert Ferdous Sarwary daniel j. fish Greg P. Brewood Albert S. Benight Department of Chemistry Portland State University Portland USA Louisville Bioscience Inc. Louisville USA Department of Chemistry and Physics Salem State University Salem USA Portland Technology Development Intel Corporation Hillsboro USA Department of Mathematics Portland State University Portland USA Department of Physics Portland State University Portland USA

Thermal denaturation and stability of two commercially available preparations of Human Serum Albumin (HSA), differing in their advertised level of purity, were investigated by differential scanning calorimetry (DSC). These protein samples were 99% pure HSA (termed HSA99) and 96% pure HSA (termed HSA96). According to the supplier, the 3% difference in purity between HSA96 and HSA99 is primarily attributed to the presence of globulins and fatty acids. Our primary aim was to investigate the utility of DSC in discerning changes in HSA that occur when the protein is specifically adducted, and determine how adduct formation manifests itself in HSA denaturation curves, or thermograms, measured by DSC. Effects of site specific covalent attachment of biotin (the adduct) on the thermodynamic stability of HSA were investigated. Each of the HSA preparations was modified by biotinylation targeting a single site, or multiple sites on the protein structure. Thermograms of both modified and unmodified HSA samples successfully demonstrated the ability of DSC to clearly discern the two HSA preparations and the presence or absence of covalent modifications. DSC thermogram analysis also provided thermodynamic characterization of the different HSA samples of the study, which provided insight into how the two forms of HSA respond to covalent modification with biotin. Consistent with published studies [1] HSA96, the preparation with contaminants that contain globulins and fatty acids seems to be comprised of two forms, HSA96-L and HSA96-H, with HSA96-L more stable than HSA99. The effect of multisite biotinylation is to stabilize HSA96-L and destabilize HSA96-H. Thermodynamic analysis suggests that the binding of ligands comprising the fatty acid and globulin-like contaminant contributes approximately 6.7 kcal/mol to the stability HSA96-L.

关键词： Human Serum Albumin (HSA) Differential Scanning Calorimetryl (DSC) Protein Thermodynamic Stability and Thermal Denaturation

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

Iron regulatory protein 1: the deadly switch of ferroptosis

引用

Neural Regeneration Research 2024年第3期19卷 477-478页

作者： daniel A.Bórquez Pamela j.Urrutia Center for Biomedical Research Faculty of MedicineUniversidad Diego PortalesSantiagoChile Institute of Nutrition&Food Technology(INTA) Universidad de ChileSantiagoChile Geroscience Center for Brain Health and Metabolism SantiagoChile

Ferroptosis,an iron-dependent cell death:Ferroptosis is a type of regulated necrosis,characterized by redox-active iron accumulation and increased free radical production derived by Fenton chemistry,that triggers oxidation of polyunsaturated fatty acids in phospholipids,loss of cellular membranes integrity,and leakage of intracellular contents.

关键词： integrity switch Iron

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

Dominance of transposable element‑related satDNAs results in great complexity of“satDNA library”and invokes the extension towards“repetitive DNA library”

引用

Marine Life Science & Technology 2024年第2期6卷 236-251页

作者： Monika Tunj.ć‑Cvitanić daniel García‑Souto j.an j.Pasantes EvaŠatović‑Vukšić Division of Molecular Biology Ruđer BoškovićInstitute10000 ZagrebCroatia Genomes and Disease Centre for Research in Molecular Medicine and Chronic Diseases(CIMUS)Universidade de Santiago de Compostela15706 Santiago de CompostelaSpain Department of Zoology Genetics and Physical AnthropologyUniversidade de Santiago de Compostela15706 Santiago de CompostelaSpain Centro de Investigación Mariña Dpto de BioquímicaXenética e InmunoloxíaUniversidade de Vigo36310 VigoSpain

Research on bivalves is fast-growing,including genome-wide analyses and genome sequencing.Several characteristics qualify oysters as a valuable model to explore repetitive DNA sequences and their genome organization.Here we char-acterize the satellitomes of five species in the family Ostreidae(Crassostrea angulata,C.virginica,C.hongkongensis,C.ariakensis,Ostrea edulis),revealing a substantial number of satellite DNAs(satDNAs)per genome(ranging between 33 and 61)and peculiarities in the composition of their satellitomes.Numerous satDNAs were either associated to or derived from transposable elements,displaying a scarcity of transposable element-unrelated satDNAs in these genomes.Due to the non-conventional satellitome constitution and dominance of Helitron-associated satDNAs,comparative satellitomics demanded more in-depth analyses than standardly employed.Comparative analyses(including C.gigas,the first bivalve species with a defined satellitome)revealed that 13 satDNAs occur in all six oyster genomes,with Cg170/HindIII satDNA being the most abundant in all of them.Evaluating the“satDNA library model”highlighted the necessity to adj.st this term when studying tandem repeat evolution in organisms with such satellitomes.When repetitive sequences with potential variation in the organizational form and repeat-type affiliation are examined across related species,the introduction of the terms“TE library”and“repetitive DNA library”becomes essential.

关键词： Satellitome Comparative satellitomics Helitron Bivalves “Dark matter of the genome”

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

Distributed Secondary Control Based on Dynamic Diffusion Algorithm for Current Sharing and Average Voltage Regulation in DC Microgrids

引用

j.urnal of Modern Power Systems and Clean Energy 2024年第2期12卷 597-607页

作者： Dawei Liao Fei Gao daniel j.Rogers Wentao Huang Dong Liu Houj.n Tang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Engineering Science University of OxfordOxford OX12JDU.K. IEEE

This paper introduces a distributed secondary control scheme for achieving current sharing and average voltage regulation obj.ctives in a DC microgrid.The proposed scheme employs a dynamic diffusion algorithm(DDA)instead of the consensus algorithm to enable distributed communication among converters.To help understand DDA,the relation of DDA and other diffusion algorithms is discussed in detail and its superiority is shown by comparison with diffusion and consensus algorithms.Furthermore,considering the discrete nature and different sampling time of the digital controller and communication network,a z-domain model of the entire DC microgrid is established.The influence of communication and secondary control parameters on the system stability is investigated.Based on the established model,the tolerable communication rates are obtained.Real-time simulations conducted on the OPAL-RT platform validate the effectiveness of the proposed scheme,showcasing its advantages in terms of convergence speed and stability.

关键词： Cooperative control DC microgrid diffusion algorithm discrete-time modeling distributed secondary control

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

Determining minimum sample size for the conditioned Latin hypercube sampling algorithm

引用

Pedosphere 2024年第3期34卷 530-539页

作者： daniel D.SAURETTE Asim BISWAS Richard j.HECK Adam W.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(DSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental covariates.Strategies to adequately sample the predictors have been well documented,with the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the DSM community.Despite advances in sampling design,a critical gap remains in determining the number of samples required for DSM proj.cts.We propose a simple workflow and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-Diaconis rule for determining optimal bin width.Data preprocessing was included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the histogram.Based on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and lower bounds of the QR were used as a scaling factor to determine minimum sample size.This technique was applied to a field-scale set of environmental covariates for a well-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of QRs.The results showed increasing minimum sample size with an increase in the QR selected.Minimum sample size increased from 44 to 83 when the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%QR.This technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin width digital soil mapping normal distribution quantile range sampling design

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

Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

引用

j.urnal of Mountain Science 2024年第3期21卷 719-733页

作者： G.Wilson FERNANDES Letícia RAMOS Dario C.PAIVA j.ssica CUNHA-BLUM Vanessa Matos GOMES daniel NEGREIROS Ecologia Evolutiva&Biodiversidade Departamento de GenéticaEcologia e Evolução/ICBUniversidade Federal de Minas Gerais31270-901Belo HorizonteMGBrazil Knowledge Center for Biodiversity 31270-901Belo HorizonteMGBrazil Department of Biological Sciences Institute of EnvironmentFlorida International UniversityMiamiFL 33199USA Programa de Pós Graduação em Biodiversidade e Uso dos Recursos Naturais Universidade Estadual de Montes ClarosMontes ClarosMGBrazil Laboratório de Estudo das Relações Solo-Planta Departamento de SolosUniversidade Federal Rural do Rio de JaneiroSeropédicaRGBrazil

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low resilience.The determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological restoration.We proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic composition.We described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and soils.All three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia subalata.The distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt concentration.We provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local conditions.Failure to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem services.This study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

关键词： Canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships

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

Finding biomarkers of experience in animals

引用

j.urnal of Animal Science and Biotechnology 2024年第3期15卷 925-944页

作者： Sarah Babington Alan j.Tilbrook Shane K.Maloney j.ll N.Fernandes Tamsyn M.Crowley Luoyang Ding Archa H.Fox Song Zhang Elise A.Kho daniel Cozzolino Timothy j.Mahony Dominique Blache School of Agriculture and Environment The University of Western AustraliaCrawleyWA 6009Australia Centre for Animal Science The Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandSt LuciaQLD 4072Australia School of Veterinary Science The University of QueenslandGattonQLD 4343Australia School of Human Sciences The University of Western AustraliaCrawleyWA 6009Australia School of Medicine Deakin UniversityGeelongVIC 3217Australia Poultry Hub Australia University of New EnglandArmidaleNSW 2350Australia College of Animal Science and Technology Yangzhou UniversityYangzhou 225009China Centre for Nutrition and Food Sciences The Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandSt LuciaQLD 4072Australia

At a time when there is a growing public interest in animal welfare,it is critical to have obj.ctive means to assess the way that an animal experiences a situation.Obj.ctivity is critical to ensure appropriate animal welfare outcomes.Existing behavioural,physiological,and neurobiological indicators that are used to assess animal welfare can verify the absence of extremely negative outcomes.But welfare is more than an absence of negative outcomes and an appropriate indicator should reflect the full spectrum of experience of an animal,from negative to positive.In this review,we draw from the knowledge of human biomedical science to propose a list of candidate biological markers(biomarkers)that should reflect the experiential state of non-human animals.The proposed biomarkers can be classified on their main function as endocrine,oxidative stress,non-coding molecular,and thermobiological markers.We also discuss practical challenges that must be addressed before any of these biomarkers can become useful to assess the experience of an animal in real-life.

关键词： Animal experience Animal welfare Biomarker Stress Welfare assessment

来源：

维普期刊数据库博看期刊

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

The secondary inj.ry cascade after spinal cord inj.ry: an analysis of local cytokine/chemokine regulation

引用

Neural Regeneration Research 2024年第6期19卷 1308-1317页

作者： daniel j.Hellenbrand Charles M.Quinn Zachariah j.Piper Ryan T.Elder Raveena R.Mishra Taylor L.Marti Phoebe M.Omuro Rylie M.Roddick j.e Sung Lee William L.Murphy Amgad S.Hanna Department of Neurosurgery University of Wisconsin-Madison School of Medicine and Public Health Department of Biomedical Engineering University of Wisconsin-Madison Department of Orthopedics and Rehabilitation University of Wisconsin-Madison Department of Materials Science and Engineering University of Wisconsin-Madison Forward BIO Institute University of Wisconsin-Madison

After spinal cord inj.ry, there is an extensive infiltration of immune cells, which exacerbates the inj.ry and leads to further neural degeneration. Therefore, a maj.r aim of current research involves targeting the immune response as a treatment for spinal cord inj.ry. Although much research has been performed analyzing the complex inflammatory process following spinal cord inj.ry, there remain maj.r discrepancies within previous literature regarding the timeline of local cytokine regulation. The obj.ctives of this study were to establish an overview of the timeline of cytokine regulation for 2 weeks after spinal cord inj.ry, identify sexual dimorphisms in terms of cytokine levels, and determine local cytokines that significantly change based on the severity of spinal cord inj.ry. Rats were inflicted with either a mild contusion, moderate contusion, severe contusion, or complete transection, 7 mm of spinal cord centered on the inj.ry was harvested at varying times post-inj.ry, and tissue homogenates were analyzed with a Cytokine/Chemokine 27-Plex assay. Results demonstrated pro-inflammatory cytokines including tumor necrosis factor α, interleukin-1β, and interleukin-6 were all upregulated after spinal cord inj.ry, but returned to uninj.red levels within approximately 24 hours post-inj.ry, while chemokines including monocyte chemoattractant protein-1 remained upregulated for days post-inj.ry. In contrast, several anti-inflammatory cytokines and growth factors including interleukin-10 and vascular endothelial growth factor were downregulated by 7 days post-inj.ry. After spinal cord inj.ry, tissue inhibitor of metalloproteinase-1, which specifically affects astrocytes involved in glial scar development, increased more than all other cytokines tested, reaching 26.9-fold higher than uninj.red rats. After a mild inj.ry, 11 cytokines demonstrated sexual dimorphisms; however, after a severe contusion only leptin levels were different between female and male rats. In conclusion, pro-inflammatory cytokines initiate the inf

关键词： astrocytes chemokines cytokines inflammation macrophages microglia secondary damage spinal cord inj.ry

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

An Assessment of Saltwater Intrusion in Coastal Regions of Lagos, Nigeria

引用

j.urnal of Geoscience and Environment Protection 2024年第1期12卷 93-119页

作者： Obunadike Callistus Akerele D. daniel Abiodun O. Pelumi Olisah Somtobe Oloyede Kunle Obunadike S. Echezona Obunadike j. Chinenye Department of Geosciences Freiberg University of Mining and Technology Freiberg Germany Department of Construction Management University of Washington Seattle USA Department of Civil Engineering Morgen State University Baltimore USA Department of Geography University of Lagos Lagos Nigeria Department of Biochemistry Anambra State University Uli Nigeria Department of Geology Anambra State University Uli Nigeria

This paper explains various factors that contribute to saltwater intrusion, including overexploitation of freshwater resources and climate change as well as the different techniques essential for effective saltwater intrusion management. The impact of saltwater intrusion along coastal regions and its impact on the environment, hydrogeology and groundwater contamination. It suggests potential solutions to mitigate the impact of saltwater intrusion, including effective water management and techniques for managing SWI. The application of A.I (assessment index) serves as a guideline to correctly identify wells with SWI ranging from no intrusion, slight intrusion and strong intrusion. The challenges of saltwater intrusion in Lagos and the salinization of wells were investigated using the hydro-chemical parameters. The study identifies four wells (“AA”, “CMS”, “OBA” and “VIL”) as having high electric conductivities, indicating saline water intrusion, while other wells (“EBM”, “IKj. and “IKO”) with lower electric conductivities, indicate little or no salt-water intrusion, and “Aj. well shows slight intrusion. The elevation of the wells also played a vital role in the SWI across coastal regions of Lagos. The study recommends continuous monitoring of coastal wells to help sustain and reduce saline intrusion. The findings of the study are important for policymakers, researchers, and practitioners who are interested in addressing the challenges of saltwater intrusion along coastal regions. We assessed the SWI across the eight (8) wells using the Assessment Index to identify wells with SWI. Wells in “CMS” and “VIL” has strong intrusions. A proposed classification system based on specific ion ratios categorizes water quality from good (+) to highly (-) contaminated (refer to Table 4). These findings underscore the need for attention and effective management strategies to address groundwater unsuitability for various purposes.

关键词： Hydro-Chemical Data Analysis Saline Incursion Aquifer Sustainability and Management Coastal Regions Ground Water Intrusion

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：