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Ground characterization and roof mapping: Online sensor signal-based change detection

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International Journal of Mining Science and Technology 2015年第6期25卷 905-913页

作者： Bahrampour Soheil Rostami Jamal Ray Asok Naeimipour Ali Collins craig Electrical Engineering Department The Pennsylvania State University Department of Energy and Mineral Engineering The Pennsylvania State University J. h. Fletcher & Co.TM

Measurement while drilling systems are becoming an important part of excavation operations for rock characterization and ground support design that require reliable information on rock strength and location ＆ frequency of joints or voids. This paper focuses on improving rock characterization algorithms for instrumented roof-boRer systems. For this purpose, an improved void detection algorithm is proposed, where the underlying theory is built upon the concept of mean change detection based on the feed pressure signals. In addition, the application of acoustic sensing for void detection is examined and it is shown that the variance of the filtered acoustic signal is correlated to the strength of the material being drilled. The proposed algorithm has been validated on the data collected from full-scale drilling tests in various concrete and rock samples at the J. h. Fletcher facility.

关键词： Measurement while drilling systemsRoof mappingVoid detectionOnline change detection

RNA Polymerase V Functions in Arabidopsis Interphase heterochromatin Organization Independently of the 24-nt siRNA-Directed DNA Methylation Pathway

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Molecular Plant 2009年第4期2卷 700-710页

作者： Olga Pontes Pedro Costa-Nunes Paul Vithayathil craig S. Pikaard Biology Department Washington University 1 Brookings Drive St Louis MO 63130 USA

In Arabidopsis, pericentromeric repeats, retroelements, and silenced rRNA genes are assembled into heterochromatin within nuclear structures known as chromocenters. The mechanisms governing higher-order heterochromatin organization are poorly understood but 24-nt small interfering RNAs （siRNAs） are known to play key roles in heterochromatin formation. Nuclear RNA polymerase IV （Pol IV）, RNA-DEPENDENT RNA POLYMERASE 2 （RDR2）, and DICER-LIKE 3 （DCL3） are required for biogenesis of 24-nt siRNAs that associate with ARGONAUTE 4 （AGO4）. Nuclear RNA polymerase V （Pol V） collaborates with DRD1 （DEFICIENT IN RNA-DEPENDENT DNA METhYLATION 1） to generate transcripts at heterochromatic loci that are hypothesized to bind to siRNA-AGO4 complexes and subsequently recruit the de-novo DNA methylation and/or histone modifying machinery. here, we report that decondensation of the major pericentromeric repeats and depletion of the heterochromatic mark histone h3 lysine 9 dimethylation at chromocenters occurs specifically in pol V and drdl mutants. Disruption of pericentromeric repeats condensation is coincident with transcriptional reactivation of specific classes of pericentromeric 180-bp repeats. We further demonstrate that Pol V functions independently of Pol IV, RDR2, and DCL3-mediated siRNA production to affect interphase heterochromatin organization, possibly by involving RNAs that recruit structural or chromatin-modifying proteins.

关键词： RNA polymerase V RNA-directed DNA methylation heterochromatin centromere gene expression.

Different Performances of h_2O_2 to Oxidise Aldicarb and hexazinone in the Advanced Oxidation Process of Ozone/hydrogen Peroxide

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Journal of Donghua University(English Edition) 2014年第3期31卷 348-353页

作者：冉治霖孙楚李绍峰 craig Denver Williams TREVOR John hocking School of Transportation and Environment Shenzhen Institute of Information Technology College of Resources and Environment Northeast Agricultural University Shenzhen Key Lab of Industrial Water Saving&Municipal Sewage Reclamation Technology Shenzhen Polytechnic Institute School of Applied Science University of WolverhamptonWolverhampton WV1 1LYUK

The degradations of hexazinone and aldicarb by direct ozonation combined an advanced oxidation process( AOP) of O3/h2O2 were investigated in this study focusing on the oxidation mechanism by identifying the hydrogen peroxide consumption during the oxidation process of the two chemicals. The results showed that h2O2 could enhance the removal rate of the triazine herbicide hexazinone,and it was consumed along with the variation of removal rate in the light of different ph levels. The addition of h2O2 contributed little to the removal of the thiocarbamate herbicide aldicarb and h2O2 content kept constantly throughout the degradation process. Tert-butyl alcohol( TBA) effectively scavenged the ·Oh radical for hexazinone,but had no effect on the removal rate of aldicarb. Aldicarb removal was mainly attributed to direct ozonation molecule in both O3( 97.00%) and O3/h2O2( 96.76%)systems. Moreover,sole O3 could hardly oxidize hexazinone whereas·Oh radicals contribute respective 74.70% and 97.50% of removal in O3 system and O3/h2O2 AOP. All of these findings suggest that the mechanism of ·Oh radical generation and the chain reaction in O3/h2O2 AOP should be further discussed.

关键词： hexazinone aldicarb O3/h2O2 direct and indirect oxidation h2O2consumption

A SPE-hPLC-MS/MS method for the simultaneous determination of pr ior itised pharmaceuticals and EDCs with high environmental risk potential in freshwater

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Journal of Environmental Sciences 2021年第2期33卷 18-27页

作者： Yuan Li MarkATaggart craig McKenzie Zulin Zhang Yonglong Lu Sabolc Pap Stuart WGibb Environmental Research Institute North Highland CollegeUniversity of the Highlands and IslandsCastle StreetThursoCaithnessScotlandKW147JDUK Forensic Drug Research Group Centre for Anatomy and Human IdentificationSchool of Science and EngineeringUK Environm ental and Biochem ical Sciences Group Ja m es Hutton InstituteCraigiebucklerA berdeen AB158QHUK Research Centre for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Novi Sad Faculty of Technical SciencesDepartment of Environmental Engineering and Occupational Safety and H ealthUniversity of Novi Sad21000 NoviSadSerbia 不详

This work describes the development,optimisation and validation of an analytical method for the rapid determination of 17 priority pharmaceutical compounds and endocrine disrupting chemicals(EDCs).Rather than studying compounds from the same therapeutic class,the analyses aimed to determine target compounds with the highest risk potential(with particular regard to Scotland),providing a tool for further monitoring in different water *** was based on a systematic environmental risk assessment approach,using consumption data;wastewater treatment removal efficiency;environmental occurrence;toxicological effects;and pre-existing regulatory *** process highlighted 17 compounds across various therapeutic classes,which were then quantified,at environmentally relevant concentrations,by a single analytical *** determination was achieved using a single-step solid phase extraction(SPE)procedure followed by high-performance liquid chromatography with tandem mass spectrometry(hPLC-MS/MS).The fully optimised method performed well for the majority of target compounds,with recoveries>71%for 15 of 17 *** limits of quantification for most target analytes(14 of 17)ranged from 0.07 ng/L to 1.88 ng/L in river *** utility of this method was then demonstrated using real water samples associated with a rural hospital/*** compounds were targeted and detected,with the highest levels found for the analgesic,paracetamol(at up to 105,910 ng/L in the hospital discharge).This method offers a robust tool to monitor high priority pharmaceutical and EDC levels in various aqueous sample matrices.

关键词： Pharmaceuticals prioritisation Risk assessment trace level determination Water quality

Subnanometer localization accuracy in widefield optical microscopy

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Light(Science & Applications) 2018年第1期7卷 740-754页

作者： craig R.Copeland Jon Geist craig D.McGray Vladimir A.Aksyuk J.Alexander Liddle B.Robert Ilic Samuel M.Stavis Center for Nanoscale Science and Technology National Institute of Standards and TechnologyGaithersburgMD 20899USA Maryland NanoCenter University of MarylandCollege ParkMD 20742USA Engineering Physics Division National Institute of Standards and TechnologyGaithersburgMD 20899USA

The common assumption that precision is the limit of accuracy in localization microscopy and the typical absence of comprehensive calibration of optical microscopes lead to a widespread issue—overconfidence in measurement results with nanoscale statistical uncertainties that can be invalid due to microscale systematic *** this article,we report a comprehensive solution to this underappreciated *** develop arrays of subresolution apertures into the first reference materials that enable localization errors approaching the atomic scale across a submillimeter *** present novel methods for calibrating our microscope system using aperture arrays and develop aberration corrections that reach the precision limit of our reference *** correct and register localization data from multiple colors and test different sources of light emission with equal accuracy,indicating the general applicability of our reference materials and calibration *** a first application of our new measurement capability,we introduce the concept of critical-dimension localization microscopy,facilitating tests of nanofabrication processes and quality control of aperture *** a second application,we apply these stable reference materials to answer open questions about the apparent instability of fluorescent nanoparticles that commonly serve as fiducial *** study establishes a foundation for subnanometer localization accuracy in widefield optical microscopy.

关键词： optical limit field

Fragility of statistically significant findings from randomized clinical trials of surgical treatment of humeral shaft fractures:A systematic review

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World Journal of Orthopedics 2022年第9期13卷 825-836页

作者： Stephen craig Morris Anirudh K Gowd Avinesh Agarwalla Wesley P Phipatanakul Nirav h Amin Joseph N Liu Department of Orthopaedic Surgery Loma Linda UniversityLoma LindaCA 92354United States Department of Orthopaedic Surgery Wake Forest University Baptist Medical CenterWinston-SalemNC 27157United States Department of Orthopaedic Surgery Westchester Medical CenterValhallaNY 10595United States Department of Orthopaedic Surgery Premier Orthopaedic and Trauma SpecialistsPomonaCA 91767United States Department of Orthopedic Surgery USC Epstein Family Center for Sports MedicineLos AngelesCA 90089United States

BACKGROUND Despite recent meta-analyses of randomized controlled trials(RCTs),there remains no consensus regarding the preferred surgical treatment for humeral shaft *** fragility index(FI)is an emerging tool used to evaluate the robustness of RCTs by quantifying the number of participants in a study group that would need to switch outcomes in order to reverse the study *** To investigate the fragility index of randomized control trials assessing outcomes of operative fixation in proximal humerus *** We completed a systematic review of RCTs evaluating the surgical treatment of humeral shaft *** criteria included:articles published in English;patients randomized and allotted in 1:1 ratio to 2 parallel arms;and dichotomous outcome *** FI was calculated for total complications,each complication individually,and secondary surgeries using the Fisher exact test,as previously *** Fifteen RCTs were included in the analysis comparing open reduction plate osteosynthesis with dynamic compression plate or locking compression plate,intramedullary nail,and minimally invasive plate *** median FI was 0 for all parameters *** individual outcomes,the FI was 0 for 81/91(89%)of *** FI exceeded the number lost to follow up in only 2/91(2%)*** The FI shows that data from RCTs regarding operative treatment of humeral shaft fractures are fragile and does not demonstrate superiority of any particular surgical technique.

关键词： humerus fracture Open reduction internal fixation Intramedullary nail Fragility index Complications Fragility index

Rock characterization while drilling and application of roof bolter drilling data for evaluation of ground conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 273-281页

作者： Jamal Rostami Sair Kahraman Ali Naeimipour craig Collins Department of Energy and Mineral Engineering Pennsylvania State University Mining Engineering Department Hacettepe University J.h. Fletcher & Co.

Despite recent advances in mine health and safety, roof collapse and instabilities are still the leading causes of injury and fatality in underground mining operations. Improving safety and optimum design of ground support requires good and reliable ground characterization. While many geophysical methods have been developed for ground characterizations, their accuracy is insufficient for customized ground support design of underground workings. The actual measurements on the samples of the roof and wall strata from the exploration boring are reliable but the related holes are far apart, thus unsuitable for design purposes. The best source of information could be the geological back mapping of the roof and walls, but this is disruptive to mining operations, and provided information is only from rock *** of the data obtained from roof bolt drilling can offer a good and reliable source of information that can be used for ground characterization and ground support design and evaluations. This paper offers a brief review of the mine roof characterization methods, followed by introduction and discussion of the roof characterization methods by instrumented roof bolters. A brief overview of the results of the preliminary study and initial testing on an instrumented drill and summary of the suggested improvements are also discussed.

关键词： Roof bolter Rock characterization Three-dimensional(3D) visualization of ground Ground support optimization

Valence Quark Ratio in the Proton

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Chinese Physics Letters 2022年第4期39卷 1-6页

作者： Zhu-Fang Cui Fei Gao Daniele Binosi Lei Chang craig D.Roberts Sebastian M.Schmidt School of Physics Nanjing UniversityNanjing 210093China Institute for Nonperturbative Physics Nanjing UniversityNanjing 210093China Centre for high Energy Physics Peking UniversityBeijing 100871China European Centre for Theoretical Studies in Nuclear Physics and Related Areas Villa TambosiStrada delle Tabarelle 286I-38123 Villazzano(TN)Italy School of Physics Nankai UniversityTianjin 300071China helmholtz-Zentrum Dresden-Rossendorf Dresden D-01314Germany RWTh Aachen University III.Physikalisches Institut BAachen D-52074Germany

Beginning with precise data on the ratio of structure functions in deep inelastic scattering(DIS)from ^3he and ^3h,collected on the domain 0.19≤xB≤0.83,where xBis the Bjorken scaling variable,we employ a robust method for extrapolating such data to arrive at a model-independent result for the xB=1 value of the ratio of neutron and proton structure *** this with information obtained in analyses of DIS from nuclei,corrected for target-structure dependence,we arrive at a prediction for the proton valence-quark ratio:d_(v)/u_(v)|_(xB→1)=0.230(57).Requiring consistency with this result presents a challenge to many descriptions of proton structure.

关键词： structure functions precise

Assessment of limiting dietary amino acids in broiler chickens offered reduced crude protein diets

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Animal Nutrition 2022年第3期10卷 1-11页

作者： craig W.Maynard Michael T.Kidd Peter V.Chrystal Leon R.McQuade Bernie V.McInerney Peter h.Selle Sonia Y.Liu Center of Excellence for Poultry Science University of ArkansasFayettevilleAR72701United States Poultry Research Foundation Faculty of ScienceThe University of Sydney425 Werombi RoadCamdenNSW2570Australia School of Life and Environmental Sciences Faculty of ScienceThe University of SydneySydneyNSW2006Australia Australian Proteome Analysis Facility Macquarie UniversitySydneyNSW2109Australia Sydney School of Veterinary Science Faculty of ScienceThe University of SydneySydneyNSW2006Australia

As lowering crude protein(CP)in poultry diets continues to minimize amino acid excess,it is important to understand the limiting order of amino acids and the impact of their ***,a pair of experiments were conducted to observe the effects of individual amino acid deletions on growth performance,carcass traits,and nutrient *** experiments involved 3 control diets based on wheat and soybean meal,including a 210.0 g/kg CP industry control(IC),186.7 g/kg CP positive control(PC)supplemented with feed-grade amino acids to match the IC amino acid profile,186.7 g/kg CP negative control(NC)with reducing N corrected apparent metabolizable energy(AMEN)by 0.5 MJ/kg and removing feed-grade amino acids beyond L-Lys-hCl,DL-Met,and L-Thr from *** deletion diets where the following supplemented amino acids were individually removed from the PC:Val,Ile,Leu,Trp,Arg,his,Phe t Tyr,glycine equivalence(Glyequi),Pro,and Energy(0.5 MJ/kg reduction in AMEN of the PC).All diets were formulated to contain similar concentrations of digestible Lys,total sulfur amino acid(TSAA)and *** diets were offered to broiler chickens from 15 to 22 d postehatch in a cage study(Exp.1)to gain digestibility and nutrient utilization data;whereas they were offered from 15 to 35 d post ehatch in a floor-pen study(Exp.2)to gain performance and carcass yield *** removal of supplemented Val,Arg,and Ile resulted in reduction on broiler performance(Phe removal of Val,Arg,Ile,and Glyequi negatively influenced carcass traits(Ph experiments indicate that Val and Arg are co-limiting in wheat-soybean meal diets,but that Ile and Glyequi may potentially limit breast and thigh development.

关键词： Amino acid Broiler chicken Crude protein Low protein diet