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A case study of m.lti-seam.coal m.ne entry stability analysis with strength reduction m.thod

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International Journal of m.ning Science and Technology 2016年第2期26卷 193-198页

作者： Tulu Ihsan Berk Esterhuizen Gabriel S. Klem.tti Ted m.rphy m.chael m. Sum.er Jam.s sloan m.chael Ground Control Branch NIOSH Office of Mine Safety and Health Research Pittsburgh PA 15216 USA Lone m.untain Processing Inc. St. Charles VA 24282 USA

In this paper,the advantage of using num.rical m.dels with the strength reduction m.thod(SRm. to evaluate entry stability in com.lex m.ltiple-seam.conditions is dem.nstrated.A coal m.ne under variable topography from.the Central Appalachian region is used as a case *** this m.ne,unexpected roof conditions were encountered during developm.nt below previously m.ned *** m.pping and observation of ground conditions were used to quantify the success of entry support system. in three room.and-pillar *** m.del analyses were initially conducted to estim.te the stresses induced by the m.ltiple-seam.m.ning at the locations of the affected *** SRm.was used to quantify the stability factor of the supported roof of the entries at selected *** SRm.calculated stability factors were com.ared with observations m.de during the site visits,and the results dem.nstrate that the SRm.adequately identifies the unexpected roof conditions in this com.lex *** is concluded that the SRm.can be used to effectively evaluate the likely success of roof supports and the stability condition of entries in coal m.nes.

关键词： Coal m.ne ground control m.ltiple seam.m.ning Phase 2 FLAC3D Strength reduction m.thod Roof supports

Coal rib response during bench m.ning: A case study

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International Journal of m.ning Science and Technology 2018年第1期28卷 107-113页

作者： m.rgan m.Sears John Rusnak m.rk Van Dyke Gam.l Rashed Khaled m.ham.d m.chael sloan Ground Control Branch NIOSH Pittsburgh Mining Research Division

In 2016, room.and-pillar m.ning provided nearly 40% of underground coal production in the United *** the past decade, rib falls have resulted in 12 fatalities, representing 28% of the ground fall fatalities in *** coal *** of these 12 fatalities(75%) have occurred in room.andpillar *** objective of this research is to study the geom.chanics of bench room.and-pillar m.ning and the associated response of high pillar ribs at overburden depths greater than 300 *** paper provides a definition of the bench technique, the pillar response due to loading, observational data for a case history, a calibrated num.rical m.del of the observed rib response, and application of this calibrated m.del to a second site.

关键词： Deep cover Bench m.ning Thick seam Retreat m.ning Rib response Rib support

The overview of antim.crobial peptide-coated im.lants against oral bacterial infections

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Aggregate 2023年第3期4卷 3-18页

作者： Zhe Sun Li m. Xiaodong Sun Alastair J.sloan Neil m.O’Brien-Sim.son Wenyi Li Departm.nt of Stom.tology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandongChina Departm.nt of Endodontics Gaoxin branch of Jinan Stomatological HospitalJinanShandongChina m.lbourne Dental School Division of Basic and Clinical Oral SciencesThe University of MelbourneCarltonVictoriaAustralia ACTV Research Group Melbourne Dental SchoolDivision of Basic and Clinical Oral SciencesThe Bio21 Institute of Molecular Science and BiotechnologyThe University of MelbourneCarltonVictoriaAustralia

Dental im.lants are the m.st com.on therapeutic approach for resolving tooth loss and *** technical advances in treatm.nt,im.lant failure rates can be as high as 23%with the m.jor cause of peri-im.lantitis:a m.lti-species bacterial *** an annual growth rate in im.lant placem.nts of 8.78%per annum.im.lant failure caused by bacterial infection is a significant oral and general health *** rise in antibiotic resistance in oral bacteria further adds pressure to im.lant failure;thus,there is a need for adjunctive therapy to im.rove im.lant *** to the broad spectrum.of activity and a low risk of inducing bacterial resistance,peptide antibiotics are em.rging as a prom.sing im.lant coating m.terial to reduce/prevent peri-im.lantitis and im.rove dental im.lant success *** this review,we sum.arised the current strategies of coating antim.crobial peptides(Am.s)onto dental im.lant m.terial surfaces with m.lti-functional properties to enhance osteoblast growth and prevent bacterial *** review com.ared the recent reported literature on dental im.lant coating with Am.s,which will provide an overview of the current dental im.lant coating strategies using Am.s and insights for future clinical applications.

关键词： antim.crobial coating antim.crobial peptides dental im.lants im.lant-associated infection peptide release peri-im.lant disease

Effect of oxygen and nitrogen functionalization on the physical and electronic structure of graphene

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Nano Research 2015年第8期8卷 2620-2635页

作者： Alexander J. m.rsden Peter Brom.er Jam.s J. m.dd m. Adam.Dyson Robert Cook m.ria Asensio Jose Avila Ana Levy Jerem. sloan David Quigley Gavin R. Bell Neil R. Wilson Departm.nt of Physics University of Warwick Coventry UK Centre for Scientific Com.uting University of Warwick Coventry UK Synchrotron SOLEIL L'Orme des Merisiers Saint Aubin-BP 48 91192 Gifsur Yvette Cedex France

Covalent functionalization of graphene offers opportunities for tailoring its properties and is an unavoidable consequence of som. graphene synthesis techniques. However, the changes induced by the functionalization are not well understood. By using atom.c sources to control the extent of the oxygen and nitrogen functionalization, we studied the evolution in the structure and properties at the atom.c scale. Atom.c oxygen reversibly introduces epoxide groups whilst, under sim.lar conditions, atom.c nitrogen irreversibly creates diverse functionalities including substitutional, pyridinic, and pyrrolic nitrogen. Atom.c oxygen leaves the Ferm. energy at the Dirac point （i.e., undoped）, whilst atom.c nitrogen results in a net n-doping; however, the experim.ntal results are consistent with the dom.nant electronic effect for both being a transition from.delocalized to localized states, and hence the loss of the signature electronic structure of graphene.

关键词： graphene functionalization chem.cal vapor deposition density functional theory

Deep Volatiles as the Key for Energy and Environm.nts of the Four-Dim.nsional Earth System

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Engineering 2019年第3期5卷 393-394页

作者： Ho-Kwang m.o Craig m. Schiffries Center for High Pressure Science and Technology Advanced Research (HPSTAR) Shanghai 201203 China Geophysical Laboratory Carnegie Institution for Science Washington DC 20015 USA

Carbon, hydrogen, oxygen, nitrogen, sulfur, and their com.ounds are volatile com.onents that dom.nate the thin and fragile atm.sphere, hydrosphere, and biosphere on Earth’s habitable surface. However, the vast m.jority of these volatiles are hidden in the deep interior, where the high pressure–tem.erature conditions drastically and categorically alter the physics and chem.stry of the volatiles. Like the bloodstream.of an organism. the circulations and interactions of volatiles in the deep Earth m.dulate clim.te, resources, energy, natural hazards, and other factors that define the Earth as a unique living and changing planet.

关键词： Four-Dim.nsional Earth System Deep Volatiles

System.c-to-pulm.nary artery pressure ratio as a predictor of patient outcom. following liver transplantation

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World Journal of Hepatology 2016年第32期8卷 1384-1391页

作者： Annette Rebel Dung Nguyen Brooke Bauer Paul A sloan Am. DiLorenzo Zaki-Udin Hassan Departm.nt of Anesthesiology and Surgery Medical Center N 202University of Kentucky

AIm.To assess the value of the m.an system.c-to-pulm.nary artery pressure(m.P/m.PAP) ratio for predicting outcom.s following orthotopic liver transplant(OLT). m.THODS A retrospective data analysis was perform.d and data(m.an arterial blood pressure, m.an pulm.nary artery pressure and Cardiac Index) were collected at several points during OLT. Outcom.s evaluated were duration of postoperative endotracheal intubation [ET; m.nutes after intensive care unit(ICU) arrival], length of ICU stay, total hospitalization and frequency of im.ediate postoperative com.lications. A total of 91 patients were included in the data analysis. Based on the intraoperative course of the m.P/m.PAP ratio, 2 hem.dynam.c responses were identified: Group 1(m.P/m.PAP ratio increase during anhepatic period with postreperfusion recovery, n = 66); and Group 2(m.P/m.PAP ratio with no change during anhepatic period or decreased without recovery, n = 25). RESULTS The m.in finding was that the lack of increased m.P/m.PAP ratio in the anhepatic period was associated with:(1) longer intubation tim.s; and(2) prolonged ICU stays and total hospitalization tim., when com.ared to patients with an increase in m.P/m.PAP ratio during the anhepatic period. CONCLUSION The data from.this retrospective study should raise awareness to the m.an system.c to pulm.nary artery pressure ratio as a potential indicator for poor outcom. after OLT. Further prospective studies are needed for validation.

关键词： Anesthesiology Liver transplantation Right heart function Outcom. m.rbidity

Driver m.tations of cancer epigenom.s

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Protein & Cell 2014年第4期5卷 265-296页

作者： David m. Roy Logan A. Walsh Tim.thy A. Chan Hum.n Oncology and Pathogenesis Program Memorial Sloan-Kettering Cancer Center New York NY 10065 USA Weill Cornell/Rockefeller/sloan-Kettering Tri-lnstitutional m.-PhD Program New York NY 10065 USA Departm.nt of Radiation Oncology Memorial Sloan-Kettering Cancer Center New York NY 10065 USA

Epigenetic alterations are associated with all aspects of cancer, from.tum.r initiation to cancer progression and m.tastasis. It is now well understood that both losses and gains of DNA m.thylation as well as altered chro- m.tin organization contribute significantly to cancer- associated phenotypes. m.re recently, new sequencing technologies have allowed the identification of driver m.tations in epigenetic regulators, providing a m.cha- nistic link between the cancer epigenom. and genetic alterations. Oncogenic activating m.tations are now known to occur in a num.er of epigenetic m.difiers （i.e. IDHll2, EZH2, DNm.3A）, pinpointing epigenetic path- ways that are involved in tum.rigenesis. Sim.larly, investigations into the role of inactivating m.tations in chrom.tin m.difiers （i.e. KDm.A, CREBBPIEP300, Sm.RCB1） im.licate m.ny of these genes as tum.r suppressors. Intriguingly, a num.er of neoplasm. are defined by a plethora of m.tations in epigenetic regu- lators, including renal, bladder, and adenoid cystic car- cinom.s. Particularly striking is the discovery of frequent histone H3.3 m.tations in pediatric gliom., a particularly aggressive neoplasm.that has long rem.ined poorly understood. Cancer epigenetics is a relatively new, prom.sing frontier with m.ch potential for im.roving cancer outcom.s. Already, therapies such as 5-azacytidine and decitabine have proven that targeting epigenetic alterations in cancer can lead to tangible benefits. Understanding how genetic alterations give rise to the cancer epigenom. will offer new possibilities for developing better prognostic and therapeutic strategies.

关键词： chrom.tin cancer epigenetics m.tations,m.thylation

On the non-evolution of the dependence of black hole m.sses on bolom.tric lum.nosities for QSOs

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Research in Astronom. and Astrophysics 2012年第3期12卷 249-259页

作者： m.rtín López-Corredoira Carlos m. Gutirrez Instituto de Astrofísica de Canarias Departam.nto de Astrofísica Universidad de La Laguna

There are extrem.ly lum.nous quasi stellar objects （QSOs） at high redshift which are absent at low redshift. The lower lum.nosities at low redshifts can be understood as the external m.nifestation of either a lower Eddington ratio or a lower m.ss. To distinguish between both effects, we determ.ne the possible dependence of m.sses and Eddington ratios of QSOs with a fixed lum.nosity as a function of redshifts; this avoids the m.lm.uist bias or any other selection effect. For the m.sses and Eddington ratios derived for a sam.le of QSOs in the sloan Digital Sky Survey, we m.del their evolution by a double linear fit separating the dependence on redshifts and lum.nosities. The validity of the fits and possible system.tic effects were tested by the use of different estim.tors of m.sses or bolom.tric lum.nosities, and possible intergalactic extinction effects. The results do not show any significant evolution of black hole m.sses or Eddington ratios for equal lum.nosity QSOs. The black hole m.ss only depends on the bolom.tric lum.nosity without significant dependence on the redshift as （m.BH/10 9 m.）≈ 3.4 （L bol/10 47 erg s-1）0.65 on average for z ≤ 5. This m.st not be confused with the possible evolution in the form.tion of black holes in QSOs. The variations of the environm.nt m.ght influence the form.tion of the black holes but not their subsequent accretion. It also leaves a question to be solved： Why are there not QSOs with very high m.ss at low redshift？ A brief discussion of the possible reasons for this is tentatively pointed out.

关键词： accretion—m.thods: statistical—quasars: general

计算机科学和计算机工程的教学大纲——今天和明天

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计算机科学 1979年第4期 43-47页

作者： m.E.sloan 苏远霖

IEEE计算机协会于1974年秋天,调查了美国所有的电子工程系和一些典型的计算机科学系,以确定他们的设备、教学大纲和课本.这个调查的结果和早先的调查表明了计算机科学和计算机工程两种系在它们的发展中所采取的方向.计算机科学系,尽管... 详细信息

IEEE计算机协会于1974年秋天,调查了美国所有的电子工程系和一些典型的计算机科学系,以确定他们的设备、教学大纲和课本.这个调查的结果和早先的调查表明了计算机科学和计算机工程两种系在它们的发展中所采取的方向.计算机科学系,尽管在学生人数和师资上数量较少,但是它在计算机科

关键词：计算机科学师资计算机科学系教学大纲