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Seven possible states of geospatial data with respect to map projection and definition: a novel pedagogical device for GIS education

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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

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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

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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

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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

Metalorganic chemical vapor deposition of InN quantum dots and nanostructures

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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

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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

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

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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

Genetic variability of the stable fly assessed on a global scale using amplified fragment length polymorphism

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Insect Science 2016年第5期23卷 695-703页

作者： Kathleen M Kneeland steven R. Skoda John e. Foster Department of entomology 103 Entomology Haft University of Nebraska-Lincoln Lincoln NE 68583 USDA-ARS-KBUSLIRL Screwworm Research Unit 2700 Fredericksburg Road Kern/ille TX 78028 USA

The stable fly, Stomoxys calcitrans （L.）（Diptera： Muscidae）, is a blood-feeding, economically important pest of animals and humans worldwide. Improved management strategies are essential and their development would benefit from studies on genetic di- versity of stable flies. especially if done on a global scale, such research could generate information necessary for the development and application of more efficient control meth- ods. Herein we report on a genetic study of stable flies using amplified fragment length polymorphism, with samples of 10-40 individuals acquired from a total of 25 locations in the Nearctic, Neotropic, Palearctic, Afrotropic and Australasian biogeographical regions. We hypothesized that genetic differentiation would exist across geographical barriers. Although Fsx （0.33） was moderately high, the Gsx （0.05; representing genetic diversity between individuals） was very low; Nm values （representing gene flow） were high （9.36）. The mismatch distribution and tests of neutrality suggested population expansion, with no genetic differentiation between locations. The analysis of molecular variance （AMOVA） results showed the majority of genetic diversity was within groups. The mantel test showed no correlation between geographic and genetic distance; this strongly supports the AMOVA results. These results suggest that stable flies did not show genetic differentiation but are panmictic, with no evidence of isolation by distance or across geographical barriers.

关键词： AFLP biting flies external parasites genetic diversity livestock pests Stomoxys calcitrans

Combination therapy for erectile dysfunction： an update review

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Asian Journal of Andrology 2011年第3期13卷 382-390,510,511页

作者： Rohit R Dhir Hao-Cheng Lin steven e Canfield Run Wang Division of Urology University of Texas Medical School at Houston Houston TX 77030 USA Department of Urology Affiliated Drum Tower Hospital Nanjing University School of Medicine Nanjing 210008 China Department of Urology University of Texas MD Anderson Cancer Center Houston TX 77030 USA

The introduction of oral phosphodiesterase-5 inhibitors （PDe51s） in the late 1990s and early 2000s revolutionized the field of sexual medicine and PDe51s are currently first-line monotherapy for erectile dysfunction （eD）. However, a significant proportion of patients with complex eD will be therapeutic non-responders to PDe51 monotherapy. Combination therapy has recently been adopted for more refractory cases of eD, but a critical evaluation of current combination therapies is lacking. A thorough PubMed and Cochrane Library search was conducted focusing on the effectiveness of combination therapies for eD in therapeutic non-responders to PDe51 therapy. Journal articles spanning the time period between January 1990 and December 2010 were reviewed. Criteria included all pertinent review articles, randomized controlled trials, cohort studies and retrospective analyses. References from retrieved articles were also manually scanned for additional relevant publications. Published combination therapies include PDe51 plus vacuum erectile device （VeD）, intraurethral medication, intracavernosal injection （ICI）, androgen supplement, a-blocker or miscellaneous combinations. Based on this review, some of these combination treatments appeared to be quite effective in preliminary testing. Caution must be advised, however, as the majority of combination therapy articles in the last decade have numerous limitations including study biases and small subject size. Regardless of limitations, present combination therapy research provides a solid foundation for future studies in complex eD management.

关键词： combination therapy intracavernosal injection erectile dysfunction phosphodiesterase-5 inhibitors vacuum erectile device