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Frontiers of physics 2013年第3期8卷 270-284页

作者： gavin j. Davies Imperial College London London SW7 2AZ United Kingdom

This article reviews the Higgs searches at the Tevatron, as presented over the summer of 2012; both standard model （SM） and beyond the standard model （BSM） results are discussed as detailed （arXiv： 1207.0449; phys. Rev. Lett., 2012, 109： 071804; phys. Rev. D, 2012, 85： 032005）. We discuss the combination of searches by the CDF and DO Collaborations for the standard model Higgs boson in the mass range 100-200 GeV/c2 produced in the the gg →H, WH, ZH, tfH, and vector boson fusion production modes, and decaying in the H → bb, H → W＋W-, H → ZZ, H →π＋π-, and H →γγ modes. The data, collected at the Fermilab Tevatron collider in p/5 collisions at √s = 1.96 TeV, correspond to integrated luminosities of up to 10 fb^-1. In the absence of signal, we expect to exclude the regions 100 〈 mH 〈 120 GeV/c2 and 139 〈 mH 〈 184 GeV/c2. We exclude, at the 95% C.L., two regions： 100 〈 mH 〈 103 GeV/c2, and 147 〈 mH 〈 180 GeV/c2. We observe a significant excess of events in the mass range between 115 and 140 GeV/c2. The local significance corresponds to 3.0 standard deviations at mH = 120 GeV/ce; the global significance （incorporating the lookelsewhere effect） for such an excess anywhere in the full mass range investigated is approximately 2.5 standard deviations. Furthermore, we separately combine searches for H→ bb-, H → W＋W- and H →γγ. We find that the excess is concentrated in the H →bb channel, appearing in the searches over a broad range of raN; the maximum local significance of 3.3 standard deviations corresponds to a global significance of approximately 3.1 standard deviations. The observed signal strengths in all channels are consistent with the expectation for a standard model Higgs boson at mH = 125 GeV/c2. The production of neutral Higgs bosons in association with b-quarks can be significantly enhanced in various beyond the standard model scenarios, including Supersymmetry. The recent combination of such searches from the two collaborations is discussed.

关键词： Higgs Tevatron

A review of bridge scour monitoring techniques

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journal of Rock Mechanics and Geotechnical Engineering 2014年第2期6卷 138-149页

作者： L.j.prendergast K.gavin School of Civil.Structural and Environmental Engineering University College Dublin

The high profile failure of the Malahide Viaduct in Dublin, Ireland, which is a part of the EU TEN-T network of critical transport links, was caused by foundation scour. Scour is a common soil-structure interaction problem. In light of current changes in climate, increasing frequency of flooding, coupled with the increasing magnitude of these flood events, will lead to a higher risk of bridge failure. Moni- toring scour is of paramount importance to ensure the continued safe operation of the aging bridge asset network. Most monitoring regimes are based on expensive underwater instrumentation that can often be subjected to damage during times of flooding, when scour risk is at its highest. This paper presents a critical review of existing scour monitoring equipments and methodologies with a particular focus on those using the dynamic response of the structure to indicate the existence and severity of the scour phenomenon affecting the structure. A sensitivity study on a recently developed monitoring method is also undertaken.

关键词： Scour Dynamics Monitoring Instruments Bridge failure

Modeling the dose-response rate/associations between VO2max and self-reported physical Activity Questionnaire in children and adolescents

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journal of Sport and Health Science 2020年第1期9卷 90-95页

作者： Alan M.Nevill Michael j.Duncan gavin Sandercock Faculty of Education Health and WellbeingUniversity of WolverhamptonWalsall CampusWalsallWS13BDUK Faculty of Health and Life Sciences Coventry UniversityCoventryCV15FBUK School of Biological Sciences University of EssexColchesterCO43SQUK

Background'. This study sought to explore the dose—response rate/association between aerobic fitness (VC)2max) and self-reported physical activity(pA) and to assess whether this association varies by sex, age, and weight ***. VO2max was assessed using the 20・m shuttle・run test. pA was assessed using the physical Activity Questionnaire (pAQ) for Adolescents(aged > 11 years, pAQ-A) or for Children (aged pAQ-C). The associations between V02raax and pAQ were analyzed using analysisof covariance (ANCOVA), adopting pAQ and pAQ2 as covariates but allowing the intercepts and slope parameters of pAQ and pAQ2 tovary with the categorical variables sex, age group, and weight ***: ANCOVA identified a curvilinear association between VO2max and pAQ, with positive linear pAQ terms that varied for both sex andweight status but with a negative pAQ2 term of —0.39 (95% confidence interval (CI): —0.57 to —0.21) that was common for all groups in regardto age, sex, and weight status. These curvilinear (inverted U) associations suggest that the benefits of increasing pA (same dose) on VO2max isgreater when children report lower levels of pA compared to children who report higher levels of pA. These dose-response rates were alsosteeper for boys and were steeper for lean children compared to overweight/obese ***'. Health practitioners should be aware that encouraging greater pA (same dose) in inactive and underweight children will result ingreater gains in V02max (response) compared with their active and overweight/obese counterparts.

关键词： Aerobic fitness Curvilinear association Sex Slope parameters Weight status

Cyclooxygenase-2 plays a central role in the genesis of pancreatitis and associated lung injury

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Hepatobiliary & pancreatic Diseases International 2005年第1期4卷 126-129页

作者： gavin O'Brien Conor j Shields Desmond C Winter john p Dillon Department Of Academic Surgery Cork University Hospital and National University of Ireland Cork Ireland William O Kirwan and H. Paul RedmondCork Ireland

BACKGROUND: The exact mechanism by which cyclooxy- genase-2 (COX-2) promotes inflammation in pancreatitis in obscure. This study was undertaken to investigate the role of COX-2 inhibition in an animal model of pancreati- tis , a disease process characterized by a systemic inflamma- tory response and ensuing neutrophil-mediated lung injury. METHODS: pancreatitis was induced in 24 Sprague-Daw- ley rats by intraperitoneal injection of 20% L-arginine (500 mg/100 g body weight). The animals were randomized into 3 groups (8 rats in each group); controls and rats with pancreatitis intravenously resuscitated with either normal saline (0.9% NaCl 3 ml/kg) at 24 and 48 hours or COX-2 inhibitor (parecoxib 1 mg/kg). pancreatic and lung inju- ries were assessed histologically. Lung injury was assessed utilizing wet;dry ratio and myeloperoxidase activity to in- dicate pulmonary neutrophil infiltration. A Western blot was used to determine COX-2 protein expression in pancrea- tic tissue. RESULTS: The animals treated with COX-2 inhibitors dis- played significantly less pancreatic and lung injuries than their normal saline counterparts. Histological pancreatic and lung injury scores were significantly reduced (p p. Lung wet: dry ratios were sig- nificantly improved and pulmonary neutrophil infiltration was attenuated in the COX-2 group (pprotein expression. CONCLUSION: This study shows, for the first time in a rat model, that adjuvant COX-2 inhibition significandy attenu- ates the severity of both pancreatitis and its associated sys- temic inflammatory response and end-organ injury.

关键词： cyclooxygenase-2 pancreatitis genesis lung injury

三维炭纤维预型体上烷烃气的催化炭沉积(英文)

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新型炭材料 2009年第3期24卷 251-259页

作者： Matthew j Thornton gavin S Walker School of Mechanical Materials and Manufacturing EngineeringUniversity of NottinghamUniversity ParkNottingham

研究了承载镍催化剂的三维(3D)炭纤维预型体,在含氢或无氢条件下,乙烷和合成天然气在其上面化学气相沉积形成的炭沉积率和碳纳米构结物。观察了炭沉积所获石墨纳米纤维、碳纳米管和石墨碳壳,得知沉积碳的纳米结构取决于沉积温度和碳源... 详细信息

研究了承载镍催化剂的三维(3D)炭纤维预型体,在含氢或无氢条件下,乙烷和合成天然气在其上面化学气相沉积形成的炭沉积率和碳纳米构结物。观察了炭沉积所获石墨纳米纤维、碳纳米管和石墨碳壳,得知沉积碳的纳米结构取决于沉积温度和碳源气组成。在650℃～800℃温间,总沉积时程直至12h,研究了烃类碳源气在氢气平衡下,从体积分数100%到20%变化情况。经Ni(NO3)2-6H2O甲醇溶液浸渍的3D炭纤维预型体在炭沉积前因溶液分解可还原出Ni。采用质量变化测定法、热谱-质谱分析仪、SEM、TEM和XRD对样品进行表征。结果表明:纤维状炭与囊包炭的比率随氢气含量的增加而增加,随反应温度的增高而减少。出乎意料的是,氢气的添加并不延长催化剂的寿命。该工艺过程对炭/炭复合材料的制备展示出良好的潜力。

关键词：催化生长炭炭纤维烷烃气浸渍显微镜方法

The emergence of pandemic influenza viruses

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protein & Cell 2010年第1期1卷 9-13页

作者： Yi Guan Dhanasekaran Vijaykrishna justin Bahl Huachen Zhu jia Wang gavin j.D.Smith State Key Laboratory of Emerging Infectious Diseases Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong SARChina

pandemic influenza has posed an increasing threat to public health worldwide in the last *** the 20th century,three human pandemic influenza outbreaks occurred in 1918,1957 and 1968,causing significant mortality.A number of hypotheses have been proposed for the emergence and development of pandemic viruses,including direct introduction into humans from an avian origin and reassortment between avian and previously circulating human viruses,either directly in humans or via an intermediate mammalian ***,the evolutionary history of the pandemic viruses has been controversial,largely due to the lack of background genetic information and rigorous phylogenetic *** pandemic that emerged in early April 2009 in North America provides a unique opportunity to investigate its emergence and development both in human and animal *** genetic analyses of data accumulated through long-term influenza surveillance provided insights into the emergence of this novel pandemic *** this review,we summarise the recent literature that describes the evolutionary pathway of the pandemic *** also discuss the implications of these findings on the early detection and control of future pandemics.

关键词： pandemic influenza influenza virus pandemics control

phosphate Glass Fibre Composites for Bone Repair

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journal of Bionic Engineering 2009年第4期6卷 318-323页

作者： Andrew j.parsons Ifty Ahmed papia Haque Ben Fitzpatrick Muhammad I.K.Niazi gavin S.Walker Chris D.Rudd Division of Materials Mechanics & StructuresFaculty of EngineeringUniversity of NottinghamNottingham NG7 2RDUK

We investigate high-modulus degradable materials intended to replace metals in biomedical *** are typically composites comprising a polylactide(pLA)matrix reinforced with phosphate glass fibres,which provide reinforcement similar to E-glass but are entirely degradable in water to produce,principally,calcium *** have made composites using a variety of fibre architectures,from non-woven random mats to unidirectional fibre *** properties in the region of 30 Gpa modulus and 350 Mpa strength have been achieved-directly comparable to quoted values for human cortical *** collaboration with other groups we have begun to consider the development of foamed systems with structures mimicking cancellous bone and this has shown significant *** fibres in these foamed structures provide improved creep resistance and reinforcement of the pore *** date the materials have exhibited excellent cellular responses in vitro and further studies are due to include consideration of the surface character of the materials and the influence of this on cell interaction, both with the composites and the glass fibres themselves,which show promise as a standalone porous scaffold.

关键词： biocomposites phosphate glass pLA porous bone repair

Maintenance of Species Differences in Closely Related Tetraploid parasitic Euphrasia (Orobanchaceae) on an Isolated Island

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plant Communications 2020年第6期1卷 85-99页

作者： Hannes Becher Max R.Brown gavin powell Chris Metherell Nick j.Riddifordand Alex D.Twyford University of Edinburgh School of Biological SciencesInstitute of Evolutionary BiologyCharlotte Auerbach RoadEdinburgh EH93FLUK Royal Botanic Garden Edinburgh 20A Inverleith RowEdinburgh EH35LRUK Botanical Society of Britain and Ireland 4 High Firs CrescentHarpendenHertfordshire AL51NAUK Schoolton Fair IsleShetland ZE29JUUK

polyploidy is pervasive in angiosperm evolution and plays important roles in adaptation and ***,polyploid groups are understudied due to complex sequence homology,challenging genome assembly,and taxonomic ***,we study adaptive divergence in taxonomically complex eyebrights(Euphrasia),where recent divergence,phenotypic plasticity,and hybridization blur species *** focus on three closely related tetraploid species with contrasting ecological preferences that are sympatric on Fair Isle,a small isolated island in the British *** a common garden experiment,we show a genetic component to the morphological differences present between these *** wholegenome sequencing and a novel k-mer approach we call“Tetmer”,we demonstrate that the species are of allopolyploid origin,with a sub-genome divergence of approximately 5%.Using2 million SNps,we show sub-genome homology across species,with a very low sequence divergence characteristic of recent *** genetic variation is broadly structured by species,with clear divergence of Fair Isle heathland Euphrasia micrantha,while grassland Euphrasia arctica and coastal Euphrasia foulaensis are more closely ***,we show that tetraploid Euphrasia is a system of allopolyploids of postglacial species divergence,where adaptation to novel environments may be conferred by old variants rearranged into new genetic lineages.

关键词： incipient speciation k-mer spectrum allopolyploidy tetraploid divergence with gene flow taxonomic complexity

Surrealism, science fiction and comics

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Surrealism, science fiction and comics