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Development of a web-platform for mining applications

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International Journal of Mining Science and Technology 2018年第1期28卷 95-99页

作者： christopher Newman Zach Agioutantis Nathaniel Schaefer Department of Mining Engineering University of Kentucky

‘‘web ground control"(web GC) provides users with instantaneous access to mine design applications anywhere, at any time, through a web *** a web-based multiple-tier architecture, users are able to easily access ground control designs, perform on-demand calculations in the field, as well as facilitate project collaborations across multiple users, devices, and operating ***, the web GC platform contains five ground control related design applications previously developed and distributed by the US National Institute of Occupational Safety and Health(NIOSH), that is, analysis of roof bolt stability(ARBS), analysis of longwall pillar stability(ALPS), analysis of retreat mining stability(ARMPS), analysis of retreat mining stability–highwall mining(ARMPS-HwM), and analysis of horizontal stress in mining(AHSM).with respect to design decisions made by the web GC development team, the web GC platform will be able to further integrate future mine design applications providing the mining industry with one of a kind umbrella suite of ground control related software available at ones *** following paper provides a detailed overview on the current state of the web GC platform with discussions ranging from back-end database development and design to the front-end user-platform *** on current progress in platform development as well as beta testing results, the web GC platform is scheduled for release in the fall of 2018.

关键词： Ground control Stability web application Cloud computing

A review of rural transformation studies:Definition,measurement,and indicators

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Journal of Integrative Agriculture 2023年第12期22卷 3568-3581页

作者： Dong wANG Chunlai CHEN christopher FINDLAY Crawford School of Public Policy Australian National UniversityCanberra 2600Australia

The paper reviews studies of rural transformation in three dimensions-definition,measurement,and indicators-and summarises the findings of rural transformation *** scope of rural transformation includes four elements-productivity,rurality,inclusiveness,and *** concepts of the dimensions of rural transformation and their associated indicators are insufficient for policy decision-making,as they lack objectivity,feasibility,accountability,comprehensiveness,and *** research to develop new measures to assess rural transformation in developing countries is ***,there is potential to explore the topic in some directions:urbanisation strategy,public intervention(i.e.,institution,policy,and investment),gender inclusiveness,market creation,and international trade.

关键词： rural transformation agricultural transformation structural change

Strategies towards statistically robust interpretations of in situ U-Pb zircon geochronology

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Geoscience Frontiers 2016年第4期7卷 581-589页

作者： christopher J.Spencer christopher L.Kirkland Richard J.M.Taylor The Institute of Geoscience Research(TIGeR) Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Centre for Exploration Targeting-Curtin Node Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Australian Research Council Centre of Excellence for Core to Crust Fluid SystemsPerthWA 6102Australia

Zircon U-Pb geochronology has become a keystone tool across Earth science, arguably providing the gold standard in resolving deep geological time. The development of rapid in situ analysis of zircon （via laser ablation and secondary ionization mass spectrometry） has allowed for large amounts of data to be generated in a relatively short amount of time and such large volume datasets offer the ability to address a range of geological questions that would otherwise remain intractable （e.g. detrital zircons as a sedi- ment fingerprinting method）. The ease of acquisition, while bringing benefit to the Earth science com- munity, has also led to diverse interpretations of geochronological data. In this work we seek to refocus U -Pb zircon geochronology toward best practice by providing a robust statistically coherent workflow. we discuss a range of data filtering approaches and their inherent limitations （e.g. discordance and the reduced chi-squared; MSwD）. we evaluate appropriate mechanisms to calculate the most geologically appropriate age from both 238U/206pb and 207pb/206pb ratios and demonstrate the cross over position when chronometric power swaps between these ratios. As our in situ analytical techniques become progressively more precise, appropriate statistical handing of U-Pb datasets will become increasingly pertinent.

关键词： Zircon Geochronology U-Pb Geostatistics MSwD

Selective and taxon-dependent effects of semi-feral cattle grazing on tree regeneration in an old-growth Mediterranean mountain forest

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Forest Ecosystems 2020年第1期7卷 128-140页

作者： Xavier Fortuny christopher Carcaillet Sandrine Chauchard Ecole Pratique des Hautes Etudes(EPHE) PSL University75014 ParisFrance Laboratoire d’ cologie des Hydrosystèmes Naturels et Anthropisés(UMR5023 CNRS UniversitéLyon 1ENTPE)69622 VilleurbanneFrance Universitéde Lorraine AgroParisTechINRAEUMR Silva54000 NancyFrance

Background:In Mediterranean mountain socio-ecosystems,both grazing by livestock and the dry season may influence tree ***,the relative contributions of these drivers are poorly known,even though present and future canopy composition might result from past and present variations in climate and herbivore *** study aims to test how semi-feral cattle presence and season affect tree ***:The study was conducted using permanent plots inside and outside a cattle exclosure in an old-growth Mediterranean *** and seedlings were counted five times per year(winter,early spring,middle spring,summer,fall)and monitored over 7 ***:Semi-feral cattle exclusion increased Acer,Fagus,Ilex,Pinus,Prunus and Quercus sapling densities and increased Acer,Fraxinus,Ilex,Quercus and Sorbus seedling ***,the dry season did not exert any noticeable effects on the sapling or seedling densities of any of the studied ***:Semi-feral cattle presence may limit tree regeneration through taxon-dependent effects,which suggests that the current decrease in grazing livestock across the Mediterranean basin will modify recruitment processes and,likely,future forest ***:Semi-feral cattle presence acts as a selective driver of tree community composition.

关键词： Cattle Climate Experiment Herbivory Forest pastoralism

Using big data and machine learning to rank traffic signals in Tennessee

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第5期10卷 918-933页

作者： christopher winfrey Piro Meleby Lei Miao Department of Engineering Technology Middle Tennessee State UniversityMurfreesboroTN 37132USA

This paper discusses low-cost approaches capable of ranking traffic intersections for the purpose of signal *** extracted intersections that are comprised of multiple roads,defined by alphanumeric traffic message channel segment codes per international classification *** of these road segments includes a variety of metrics,including congestion,planning time index,and bottleneck ranking information provided by the Regional Integrated Transportation Information *** first approach was to use a ranking formula to calculate intersection rankings using a score between 0 and 10 by considering data for different times of the day and different days of the week,weighting weekdays more heavily than weekends and morning and evening commute times more heavily than other times of *** second method was to utilize unsupervised machine learning algorithms,primarily k-means clustering,to accomplish the intersection ranking *** first approach this by checking the performance of basic k-means clustering on our data *** then explore the ranking problem further by utilizing data provided by traffic professionals in the state of *** exploration involves using MATLAB to minimize the mean-squared error of intersection rankings to determine the optimum weights in the ranking formula based on a city’s professional *** then attempted an optimization of our weights via a brute-force search approach to minimize the distance from ranking formula results to the clustering *** the ranking information was aggregated into an online SQL database hosted by Amazon web services that utilized the PHP scripting language.

关键词： Unsupervised machine learning Clustering k-means Traffic signals

The mystery is solved--CatSper is the principal calcium channel activated by progesterone in human spermatozoa

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Asian Journal of Andrology 2011年第3期13卷 351-352页

作者： christopher LR Barratt Reproductive and Developmental Biology Maternal and Child Health Science Laboratories Centre for Oncology and Molecular Medicine Ninewells Hospital University of Dundee Dundee Scotland DD1 9SY UK

Aremarkable advance in sperm physiology has recently been published in Nature. Two groups using patch damping techniques on human sperm have solved a mystery about the sperm cell that has puzzled both andrologists and those involved in non-genomic cellular signalling for over 20 years. In these papers, Lishko1 and Strunker2 independently demonstrate that the universal characteristic effect of progesterone on sperm--a rapid influx of calcium--is via a sperm-specific channel CatSper.

关键词： Semen Lymphocytes Genomes

Invasion reproductive numbers for periodic epidemic models

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Infectious Disease Modelling 2019年第1期4卷 124-141页

作者： christopher Mitchell christopher Kribs Department of Mathematics Tarleton State UniversityStephenvilleTX 76402USA Department of Mathematics University of Texas at ArlingtonArlingtonTX 76019-0408USA

There are many cases within epidemiology where infections compete to persist within a *** studying models for such cases,one of the goals is to determine which infections can invade a population and persist when other infections are already resident within the *** reproductive numbers(IRN),which are tied to the stability of boundary endemic equilibria,can address this *** reinterpreting resident infections epidemiologically,this study extends methods for finding IRNs to periodic systems,and presents some examples which illustrate the often complex computations *** identify conditions under which a simple time-average can be used to derive IRNs,and apply the methods to examine how seasonal fluctuations in influenza incidence facilitate the year-round persistence of bacterial respiratory infections.

关键词： Mathematical epidemiology Periodic models Basic reproductive number

"Micro-deletions" of the human Y chromosome and their relationship with male infertility

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Journal of Genetics and Genomics 2008年第4期35卷 193-199页

作者： Zheng Li christopher J Haines Yibing Han Renji Hospital School of Medicine Shanghai Jiaotong University Shanghai Institute of Andrology Shanghai 200001 China Department of Obstetrics and Gynaecology Prince of Wales Hospital The Chinese University ofHong Kong Shatin NT Hong Kong SAR China

The Y chromosome evolves from an autochromosome and accumulates male-related genes including sex-determining region of Y-chromosome （SRY） and several spermatogenesis-related genes. The human Y chromosome （60 Mb long） is largely composed of repetitive sequences that give it a heterochromatic appearance, and it consists of pseudoautosomal, euchromatic, and heterochromatic regions. Located on the two extremities of the Y chromosome, pseudoautosomal regions 1 and 2 （PAR1 and PAR2, 2.6 Mb and 320 bp long, respectively） are homologs with the termini of the X chromosome. The euchromatic region and some of the repeat-rich heterochromatic parts of the Y chromosome are called ＂male-specific Y＂（MSY）, which occupy more than 95% of the whole Y chromosome. After evolution, the Y chromosome becomes the smallest in size with the least number of genes but with the most number of copies of genes that are mostly spermatogenesis-related. The Y chromosome is characterized by highly repetitive sequences （including direct repeats, inverted repeats, and palindromes） and high polymorphism. Several gene rearrangements on the Y chromosome occur during evolution owing to its specific gene structure. The consequences of such rearrangements are not only loss but also gain of specific genes. One hundred and fifty three haplotypes have been discovered in the human Y chromosome. The structure of the Y chromosome in the GenBank belongs to haplotype R1. There are 220 genes （104 coding genes, 111 pseudogenes, and 5 other uncategorized genes） according to the most recent count. The 104 coding genes encode a total of about 48 proteins/protein families （including putative proteins/protein families）. Among them, 16 gene products have been discovered in the azoospermia factor region （AZF） and are related to spermatogenesis. It has been discovered that one subset of gene rearrangements on the Y chromosome, ＂micro-deletions＂, is a major cause of male infertility in some populations. However, controversies e

关键词： human Y-chromosome micro-deletion male infertility

Applying reticular synthesis to the design of Cu-based MOFs with mechanically interlocked linkers

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Nano Research 2021年第2期14卷 417-422页

作者： Alexander J.Stirk Benjamin H.wilson christopher A.O’Keefe Hazem Amame Kelong Zhu Robert w.Schurko Stephen J.Loeb Department of Chemistry and Biochemistry University of WindsorWindsorOntarioN9B 3B4Canada Department of Chemistry The University of JordanAmman11942Jordan School of Chemistry Sun Yat-Sen UniversityGuangzhou 510275China Department of Chemistry and Biochemistry Florida State UniversityTallahasseeFlorida 32306-4390USA

The concept of“robust dynamics”describes the incorporation of mechanically interlocked molecules(MIMs)into metal-organic framework(MOF)materials such that large amplitude motions(e.g.,rotation or translation of a macrocycle)can occur inside the free volume pore of the *** aid in the preparation of such materials,reticular synthesis was used herein to design rigid molecular building blocks with predetermined ordered structures starting from the well-known MOF *** linkers were synthesized that have a T-shape,based on a triphenylene tetra-carboxylate strut,and their incorporation into Cu(II)-based MOFs was *** single-crystal structures of three new MOFs,UwCM-12(fof),β-UwCM-13(loz),UwCM-14(lil),with naked T-shaped linkers were determined;β-UwCM-13 is the first reported example of the loz topology.A fourth MOF,UwDM-14(lil)is analogous to UwCM-14(lil)but contains a[2]rotaxane ***-temperature,^(2)H solid-state NMR was used to probe the dynamics of a 24-membered macrocycle threaded onto the MOF skeleton.

关键词： reticular chemistry metal-organic frameworks mechanically interlocked molecules rotaxane