检索结果-南通市图书馆

Geo-Spatial Information Science 2018年第4期21卷 288-293页

作者： steven e.greco Department of Human ecology University of CaliforniaDavisCAUSA

Conceptually,the theory and implementation of“map projection”in geographic information system(GIS)technology is difficult to comprehend for most introductory students and novice *** this difficulty is the concept of a“map projection file”that defines map projection parameters of geo-spatial *** problem of the“missing projection file”appears ubiquitous for all users,especially in practice where data is widely *** common problem is inadvertent misapplication of the“Define Projection”tool that can result in a GIS dataset with an incorrectly defined map projection *** education should provide more guidance in differentiating the concepts of map projection versus projection files by increasing understanding and minimizing common errors.A novel pedagogical device is introduced in this paper:the seven possible states of GIS data with respect to map projection and *** seven possible states are:(1)a projected coordinate system(PCS)that is correctly defined,(2)a PCS that is incorrectly defined,(3)a PCS that is undefined,(4)a geographic coordinate system(GCS)that is correctly defined,(5)a GCS that is incorrectly defined,(6)a GCS that is undefined,and(7)a *** created automated troubleshooting tools to determine a missing map projection file are discussed.

关键词： GIS education map projection error map projection file define projection

DNA alkylation promoted by an electron-rich quinone methide intermediate

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and engineering 2016年第2期10卷 213-221页

作者： Chengyun Huang steven e. Rokita Department of Chemistry and Biochemistry University of Maryland College Park MD 20742 USA Sichuan Institute of Geological engineering Investigation Chengdu 610072 China Department of Chemistry Johns Hopkins University Baltimore MD 21218 USA

Biological application of conjugates derived from oligonucleotides and quinone methides have pre- viously been limited by the slow exchange of their covalent self-adducts and subsequent alkylation of target nucleic acids. To enhance the rates of these processes, a new quinone methide precursor with an electron donating substituent has been prepared. Additionally, this substi- tuent has been placed para to the nascent exo-methylene group of the quinone methide for maximum effect. A conjugate made from this precursor and a 5＇-aminohex- yloligonucleotide accelerates formation of its reversible self-adduct and alkylation of its complementary DNA as predicted from prior model studies.

关键词： quione methide DNA alkylation reversible covalent reaction bioconjugation target-directed modification of nucleic acids

维普期刊数据库

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2012年第1期14卷 136-137页

作者： Andrea A Chan steven e Canfield Run Wang Division of Urology University of Texas Medical School at Houston Houston TX 77030 USA Department of Urology University of Texas MD Anderson Cancer Center Houston TX 77030 USA

The Scandinavian Prostate Cancer Group- 4 recently reported the long-term survival benefit in men who were randomized to radical prostatectomy versus men watchful waiting for localized prostate cancer.1 The authors have now presented the companion article that updates the long-term quality of life evaluation in these men.2 Given the excellent prognosis of patients with early stage prostate cancer, the impact of therapy on patient＇s quality of life is a significant factor in the optimal management of this disease.

关键词： Health-related quality of life Scandinavian patients radical prostatectomy watchful waiting

A cross-analysis framework formulti-source volunteered, crowdsourced, and authoritative geographic information: The case study of volunteered personal traces analysis against transport network data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2018年第3期21卷 257-271页

作者： Gloria Bordogna steven Capelli Daniele e.Ciriello Giuseppe Psaila CNR IReA MilanoItaly DISCo Universitádegli studi di Milano BicoccaSesto San GiovanniItaly DIGIP University of BergamoDalmineItaly

The paper discusses the need of a high-level query language to allow analysts,geographers and,in general,non-programmers to easily cross-analyze multi-source VGI created by means of apps,crowd-sourced data from social networks and authoritative geo-referenced data,usually represented as JSON data sets(nowadays,the de facto standard for data exported by social networks).Since an easy to use high-level language for querying and manipulating collections of possibly geo-tagged JSON objects is still unavailable,we propose a truly declarative language,named J-CO-QL,that is based on a well-defined execution model.A plug-in for a GIS permits to visualize geo-tagged data sets stored in a NoSQL database such as MongoDB;furthermore,the same plug-in can be used to write and execute J-CO-QL queries on those *** paper introduces the language by exemplifying its operators within a real study case,the aim of which is to understand the mobility of people in the neighborhood of Bergamo ***-analysis of data about transportation networks and VGI from travelers is performed,by means of J-CO-QL language,capable to manipulate and transform,combine and join possibly geo-tagged JSON objects,in order to produce new possibly geo-tagged JSON objects satisfying users’needs.

关键词： Cross-analysis framework comparing VGI crowd-sourced and authoritative geographical data JSON data-sets declarative query language heterogeneous data-sets

Management of residual penile curvature after penile prosthesis placement

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2021年第2期23卷 129-134页

作者： Denis V Krakhotkin David J Ralph Gideon A Blecher Volodymyr A Chernylovskyi Francesco greco evgeny e Bakurov Ruslan A Bugaev Central District Hospital Outpatient DepartmentKamenolomniRostov Region 346480Russia University College London St Peter’s Andrology Centre and University College London Hospitals London W1G 6BJUnited Kingdom Monash University Department of SurgeryMelbourne 3168Australia The Alfred Hospital Department of UrologyMelbourne 3004Australia Department of Urology 1 City Clinical Hospital No.4Dnipro 49102Ukraine Department of Urology Humanitas GavazzeniBergamo 24125Italy Department of Surgery No.1 Rostov Regional Hospital ROKB 1Rostov-on-Don 344015Russia

Residual penile curvature is a common situation following the implantation of a penile prosthesis in patients with Peyronie’s ***,there is a variety of options for the correction of residual curvature,including penile modeling,plication techniques,as well as tunical incision/excision with or without grafting.A literature search of PubMed and Medline databases was conducted from 1964 until 2020,using search terms for all articles in the english *** this article,we provide a review of the techniques and the outcomes,according to the published literature.

关键词： grafting modeling penile curvature penile implant penile prosthesis Peyronie’s disease tunical plication

Metalorganic chemical vapor deposition of InN quantum dots and nanostructures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2021年第8期10卷 1409-1420页

作者： Caroline e.Reilly Stacia Keller Shuji Nakamura steven P.DenBaars Materials University of CaliforniaSanta BarbaraCA 93106USA electrical and Computer engineering University of CaliforniaSanta BarbaraCA 93106USA

Using one material system from the near infrared into the ultraviolet is an attractive goal,and may be achieved with(ln,AI,Ga)***Ⅲ-N material system,famous for enabling blue and white solid-state lighting,has been pushing towards longer wavelengths in more recent *** a bandgap of about 0.7 eV,InN can emit light in the near infrared,potentially overlapping with the part of the electromagnetic spectrum currently dominated byⅢ-As andⅢ-P *** has been the case in these otherⅢ-V material systems,nanostructures such as quantum dots and quantum dashes provide additional benefits towards optoelectronic *** the case of InN,these nanostructures have been in the development stage for some time,with more recent developments allowing for InN quantum dots and dashes to be incorporated into larger device *** review will detail the current state of metalorganic chemical vapor deposition of InN nanostructures,focusing on how precursor choices,crystallographic orientation,and other growth parameters affect the *** optical properties of InN nanostructures will also be assessed,with an eye towards the fabrication of optoelectronic devices such as light-emitting diodes,laser diodes,and photodetectors.

关键词： optoelectronic quantum chemical

Targeting duplex DNA with the reversible reactivity of quinone methides

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2016年第1期1卷 101-105页

作者： Chengyun Huang Yang Liu steven e Rokita Department of Chemistry and Biochemistry University of MarylandCollege ParkMDUSA Chengdu Integrated Testing Center of Rocks and Ores ChengduSichuanChina National Institutes for Food and Drug Control BeijingChina Department of Chemistry Johns Hopkins UniversityBaltimoreMDUSA.

DNA alkylation and crosslinking remains a common and effective strategy for anticancer chemotherapy despite its infamous lack of *** a reactive group to a sequence-directing component has the potential to enhance target selectivity but may suffer from premature degradation or the need for an external signal for ***,quinone methide conjugates may be employed if they form covalent but reversible adducts with their sequence directing *** resulting self-adducts transfer their quinone methide to a chosen target without an external signal and avoid off-target reactions by alternative intramolecular *** transfer is shown to depend on the nature of the quinone methide and the sequencedirecting ligand in applications involving alkylation of duplex DNA through a triplex recognition *** required an electron-rich derivative that enhanced the stability of the transient quinone methide intermediate and a polypyrimidine strand of DNA to associate with its cognate polypurine/polypyrimidine *** quinone methide conjugates with peptide nucleic acids were capable of quinone methide transfer from their initial precursor but not from their corresponding *** active peptide nucleic acid derivatives were highly selective for their complementary target.

关键词： reversible alkylation reactivity

Design of a water curtain to reduce accumulations of float coal dust in longwall returns

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2020年第4期30卷 443-447页

作者： Clara e.Seaman Michael R.Shahan Timothy W.Beck steven e.Mischler National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

Accumulation of float coal dust(FCD)in underground mines is an explosion hazard that affects all underground coal mine *** this hazard is addressed by the application of rock dust,inadequate rock dusting practices can leave miners exposed to an explosion *** at the National Institute for Occupational Safety and Health(NIOSH)have focused on developing a water curtain that removes FCD from the airstream,thereby reducing the buildup of FCD in mine *** this study,the number and spacing of the active sprays in the water curtain were varied to determine the optimal configuration to obtain peak knockdown efficiency(Ke)while minimizing water consumption.

关键词： Float coal dust Longwall Water spray Knockdown efficiency explosion prevention Dust control

维普期刊数据库

A two-phase model for fast geomorphic shallow flows

在线全文

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2012年第4期27卷 409-425页

作者： Massimo greco Michele IeRVOLINO Angelo LeOPARDI Andrea VACCA Dipartimento di Ingegneria Idraulica Geotecnica ed Ambientale-Universita di Napoli “Federico Ⅱ”via Claudio 21-80125 NapoliITALY Prof. Dipartimento di Ingegneria Civile e Meccanica-Universita di Cassino e del Lazio Meridionale via Di Biasio 43-03043 Cassino(FR)ITALY Assis.Prof.Dr. 4. Dipartimento di Ingegneria Civile-Seconda Universita di Napolivia Roma 29-81031 Aversa(CE)ITALY Assoc.Prof.Dr. Dipartimento di Ingegneria Civile-Seconda Universita di Napoli via Roma 29-81031 Aversa(CE)ITALY Assis.Prof.Dr.

The paper introduces a 2D shallow water model based on a two-phase formulation for the analysis of fast geomorphic transients occurring in the context of river *** and momentum conservation principles are separately imposed for both *** model naturally accounts for non-equilibrium solid transport,since neither instantaneous adaptation hypothesis nor any lag equation is employed to represent sediment *** hyperbolic character of the proposed model is shown to be preserved independently on the flow *** from numerical simulations of both 1D and 2D test-cases are compared with literature experimental data and with available numerical solutions.

关键词： Morphodynamic model Non-equilibrium sediment transport Two-phase shallow-water model eigenvalues analysis Dam-break flows

Smurfs have“fused”into the asymmetric division of stem cells

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Protein & Cell 2011年第1期2卷 2-4页

作者： steven Y.Cheng Ying e.Zhang Department of Developmental Genetics Center for Regenerative MedicineNanjing Medical University140 Hanzhong RoadNanjing 210029China Laboratory of Cellular and Molecular Biology National Cancer InstituteNational Institutes of Health37 Convent DriveBethesdaMD 20892USA

The asymmetric cell division is the way in which a stem cell divides into one daughter stem cell and one differentiated daughter *** process is one of the key principles of developmental biology that ensures the perpetual supply of stem cells while allowing a particular cell lineage to be *** Drosophila oogenesis,the fate of the daughter stem cell produced from the asymmetric division of germline stem cells(GSCs)is specified by Decapentaplegic(Dpp),but the other daughter cell has almost equal access to the Dpp *** Dpp signaling is inactivated in the differentiated daughter cell has been a deep mystery until a recent study,led by Dahua Chen of the Institute of Zoology,China(Xia et al.,2010),showed that the Dpp receptor,Thick vein(Tkv),is degraded specifically in the differentiated daughter cell by an HeCT-domain ubiquitin e3 ligase,Smurf,in conjunction with a serine-threonine kinase Fused(Fu).This finding is as much revealing as it is surprising,because up until now Fu is considered a core member of the Hedgehog signaling pathway.

关键词： daughter asymmetric fused

维普期刊数据库