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Higgs boson searches at the Tevatron

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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

Lymphoepithelial cysts of the pancreas:a management dilemma

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Hepatobiliary & Pancreatic diseases International 2014年第5期13卷 539-544页

作者： julie Martin Keith j Roberts Maria Sheridan gavin A Falk daniel joyce R Matthew Walsh Andrew M smith Gareth Morris-Stiff departments of Pancreatic Surgery St James's University Hospital departments of Radiology St James's University Hospital department of General Surgery Section of Surgical Oncology/HPB Cleveland Clinic Foundation

Pancreatic lymphoepithelial cysts（LECs） are rare,benign lesions that are typically unexpected post-operative pathological findings. We aimed to review clinical, radiological and pathological features of LECs that may allow their preoperative diagnosis. Histopathology databases of two large pancreatic units were searched to identify LECs and notes reviewed to determine patient demographic details, mode of presentation, investigations, treatment and outcome. Five male and one female patients were identified. Their median age was 60 years. Lesions were identified on computed tomography performed for abdominal pain in two patients, and were incidentally observed in four patients. Five LECs were located in the tail and one in the body of the pancreas, with a median cyst size of 5 cm. Obtaining cyst fluid was difficult and a largely acellular aspirate was yielded. The pre-operative diagnosis was mucinous cystic neoplasm in all patients. This series of patients were treated distal pancreatectomy and splenectomy. A retrospective review of radiological examinations suggested that LECs have a relatively low signal on T2 imaging and a high signal intensity on T1 weighted images. LECs appear more common in elderly males, and are typically incidental, large, unilocular cysts. Close attention to signal intensity on MRI may allow preoperative diagnosis of these lesions.

关键词： lymphoepithelial cyst pancreas

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 d 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

Isoform-and cell-state-specific APOE homeostasis and function

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Neural Regeneration Research 2024年第11期19卷 2456-2466页

作者： Karina Lindner Anne-Claude gavin department of Cell Physiology and Metabolism Faculty of MedicineUniversity of GenevaGenevaSwitzerland diabetes Center Faculty of MedicineUniversity of GenevaGenevaSwitzerland

Apolipoprotein E is the major lipid transporter in the brain and an important player in neuron-astrocyte metabolic *** ensures the survival of neurons under stressful conditions and hyperactivity by nourishing and detoxifying *** E polymorphism,combined with environmental stresses and/or age-related alterations,influences the risk of developing late-onset Alzheimer’s *** this review,we discuss our current knowledge of how apolipoprotein E homeostasis,*** synthesis,secretion,degradation,and lipidation,is affected in Alzheimer’s disease.

关键词： Alzheimer’s disease apolipoprotein E autophagy cholesterol lipid detoxification lipid transport lysosomal failure metabolic impairment triacylglycerol

decentralized Control of Multiagent Navigation Systems

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IEEE/CAA journal of Automatica Sinica 2022年第5期9卷 922-925页

作者： Boyang Zhang Henri P.gavin IEEE department of Civil and Environmental Engineering Duke UniversityDurhamNC 27708 USA

dear editor,In this letter,we introduce a decentralized,nonlinear,discontinuous,and computationally simple control law for large scale multiagent navigation *** control is based on extending Gauss’s principle of least constraint with a dynamic incorporation of inequality constraints,actuator saturation,and actuator *** no individual path planner,each agent executes its motion and generates its control actions by reacting solely to the evolution of its constrained dynamics,which is equivalent to solving a linear matrix equation with a dimension up to around 20 without iteration at each time *** experiments are conducted on hundreds of two-dimensional(2-d)double integrators subjected to path and collision constraints,demonstrating the promise of the proposed method.

关键词： dynamics method constraints

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

Karrikin and Cyanohydrin Smoke Signals Provide Clues to New Endogenous Plant Signaling Compounds

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Molecular Plant 2013年第1期6卷 29-37页

作者： gavin R. Flematti Mark T. Waters Adrian Scaffidi david j. Merritt Emilio L. Ghisalberti' Kingsley W.dixon Steven M. smith School of Chemistry and Biochemistry University of Western Australia Crawley 6009 Western Australia Australia Centre in Plant Energy Biology University of Western Australia Crawley 6009 Western Australia Australia School of Plant Biology University of Western Australia Crawley 6009 Western Australia Australia Kings Park and Botanic Garden Fraser Avenue West Perth 6005 Western Australia Australia

Two new types of signaling compounds have been discovered in wildfire smoke due to their ability to stimulate seed germination. The first discovered were karrikins, which share some structural similarity with the strigol- actone class of plant hormones, and both signal through a common F-box protein. However, karrikins and strigolactones operate through otherwise distinct signaling pathways, each distinguished by a specific a/13 hydrolase protein. Genetic analysis suggests that plants contain endogenous compounds that signal specifically through the karrikin pathway. The other active compounds discovered in smoke are cyanohydrins that release germination-stimulating cyanide upon hydrolysis. Cyanohydrins occur widely in plants and have a role in defense against other organisms, but an additional role in endogenous cyanide signaling should also now be considered.

关键词： fire smoke karrikins strigolactones cyanohydrins cyanide seed germination Arabidopsis thaliana.

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