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Early evolution of vertebrate photoreception: lessons from lampreys and lungfishes

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Integrative Zoology 2009年第1期4卷 87-98页

作者： Shaun P.collin Sensory Neurobiology Group School of Biomedical SciencesThe University of QueenslandBrisbaneAustralia

Lampreys(Agnatha)and lungfish(Dipnoi)are representatives of the earliest and the intermediate stages in ver-tebrate evolution,respectively,and survived in the Cambrian(approximately 540 mA,lampreys)and Devonian(approximately 400 mA,lungfishes)*** unique phylogenetic position of these two groups presents us with an exciting opportunity to understand life in ancient times and to begin to trace the evolution of vision and photoreception in *** a multidisciplinary approach employing anatomical and molecular techniques,the evolution of photoreception is explored in these extant,living fossils to predict the environmental lighting conditions to which our vertebrate ancestors were *** to expectations,the retinae of the southern hemisphere lamprey(Geotria australis Gray,1851)and the Australian lungfish(Neoceratodus forsteri Krefft,1870)are far from“primitive,”each possessing five types of photoreceptors,many with spectral filters for tuning the *** ultrastructural analysis reveals that all five receptor types in *** are cone-like,whereas *** possesses four cone types and a single type of *** receptor type also contains a different visual pigment(opsin gene);that is,LWS,SWS1,SWS2,RhA and RhB in *** and LWS,SWS1,SWS2,Rh1 and Rh2 in ***,all of which are expressed within the retina and are sensitive to different parts of the electromagnetic spectrum,providing the potential for pentachromatic and tetrachromatic color vision,respectively.

关键词： color vision evolution fishes photoreceptors retina.

Anisotropic modelling of Opalinus Clay behaviour: From triaxial tests to gallery excavation application

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第3期9卷 53-66页

作者： Francois Bertrand Frédéric collin Université de Liège Département ArGEnCo/Géomécanique Allée de la découverte 9 4000 Liège Belgium F.R.I.A Fonds de la Recherche Scientifique e FNRS Brussels Belgium

Deep repository in geological formations is the preferential solution considered in many countries to manage high-level nuclear wastes. In Switzerland, the Opalinus Clay is a candidate host rock. In this context, in situ and laboratory tests are conducted on Opalinus Clay to demonstrate the feasibility of deep disposal in this argillaceous formation. This paper presents a constitutive model able to fit the experimental data obtained from some triaxial tests conducted by Jahns(2013) on cores from borehole Schlattingen SLA-1. The elasto-plastic behaviour of Opalinus Clay is reproduced thanks to a DruckerPrager model, taking into account the anisotropy behaviour of this sedimentary rock. The objective is to employ a single set of parameters representative of the material. In a second version of the model, the stress-dependence of the elastic properties and damage are taken into account. Finally, the parameters calibrated with experimental tests are used to simulate the excavation of a gallery with a second gradient approach.

关键词： Opalinus Clay Schlattingen Constitutive modelling Anisotropy Dilatancy Localisation Tunnel excavation

Application of Kaiser Sepsis Calculator in culture-positive infants with early onset sepsis

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World Journal of Pediatrics 2021年第4期17卷 429-433页

作者： Gretchen Kopec Marc collin Anirudha Das Department of Neonatology University of Illinois College of MedicinePeoria campusPeoriaUSA Department of Neonatology MetroHealth Medical CenterClevelandUSA Department of Neonatology Cleveland Clinic Children’s Hospital9500 Euclid AvenueClevelandOH44195USA

Background Kaiser Sepsis Calculator(KSC)reduces antibiotic use,testing and intravenous infiltrates but there are concerns about the missed early onset sepsis(EOS)*** sought to apply the KSC score for culture-positive infants retrospectively in infants born in the last 10 years in our *** In a retrospective cohort study,the comparison groups were divided into Group A(no antibiotics recommended by KSC)and Group B(antibiotics recommended).Results Overall,17/24(71%)infants would have been started on antibiotics per KSC but 7/24(29%)would *** initial EOS risk was not significantly different between the groups(Group A *** B:0.44 vs.0.76,P=0.41),but the final risk score was(0.33 vs.9.41,P<0.001).In Group A(no antibiotics),3/7 infants became symptomatic between 9 and 42 *** There may be a potential delay in starting antibiotics in infants that are asymptomatic at birth while using KSC.

关键词： Early onset sepsis EOS Kaiser Sepsis Calculator Neonatal sepsis Neonate Newborn Blood culture

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

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

Asia–Gondwana connections indicated by Devonian fishes from Australia:palaeogeographic considerations

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Journal of Palaeogeography 2020年第2期9卷 128-149页

作者： gavin Charles Young Jing Lu Department of Applied Mathematics Research School of PhysicsAustralian National UniversityCanberraAustralia Australian Museum Research Institute SydneyAustralia Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology&PaleoanthropologyChinese Academy of SciencesBeijing 10004China CAS Center for Excellence in Life and Paleoenvironment Beijing 10004China.

Middle Palaeozoic vertebrate fossil occurrences are summarised for Australia, with reference to faunal connections between Asia and East Gondwana, as first indicated by fish distributions of Lower Devonian fossil sites. Major endemic groups discussed are pituriaspid(Australian) and galeaspid(Asian) agnathans, wuttagoonaspids(Australian)and antarctaspid(Antarctic, Australian, Asian) arthrodires, yunnanolepid and sinolepid antiarchs(South China,Indochina terrane, Australia), and early tetrapodomorphs(South China, Australia). More widespread groups that lived in shallow marine environments(lungfishes, buchanosteid arthrodires, antiarch Bothriolepis) also show species groups shared between South China and East Gondwana. Exchange of continental facies fishes(e.g. tristichopterid tetrapodomorphs) may have been interrupted by marine transgression in the Frasnian, but were restored in the late Famennian with the appearance of Grenfellaspis in eastern Australia, the only sinolepid antiarch known from outside Asia. The hypothesis of Gondwana dispersion and Asian accretion, to explain the collage of geological terranes forming modern east and southeast Asia, implies increasing dissimilarity with increasing age, but the SiluroDevonian early vertebrate evidence is inconsistent with this. Previous cladistic analysis of Asian terranes predicted galeaspid agnathans on the Indochina terrane, and their subsequent discovery at Ly Hoa, Vietnam, confirms that Indochina and South China had come together across the Song Ma suture by Middle Devonian time.

关键词： Devonian Palaeogeography Biogeography Vertebrates East Gondwana South China Indochina terrane

Improving health care usage in a very low birth weight population

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World Journal of Pediatrics 2015年第3期11卷 239-244页

作者： Wambui Waruingi Sai Iyer Marc collin Department of Pediatrics Division of NeonatologyCase Western ReserveMetrohealth Medical Center2500 Metrohealth DriveClevelandOH 44109USA Department of Pediatrics Cincinnati Children's Hospital Medical Center3333 Burnett avenueCincinnatiOH 45229USA

Background:Prematurity is the biggest contributor to admissions in the neonatal intensive care unit(NICU).The period following hospital discharge is a vital continuum for the very low birth weight(VLBW)infant The objective of this study was to assess the impact of a unique discharge and follow-up process on the outcomes of VLBW infants leaving the ***:All outpatient health care usage by VLBW infants born in the study year(cases)was retrospectively tracked through 12 months of age.A cohort of healthy newborn infants were matched by birthdate to each VLBW infant(controls)and similarly ***:In this study,there were 85 cases and 85 *** mean gestational age at birth for the cases was 29.1±2.7 weeks with a mean birth weight of 1079±263 *** of the controls was 38.9±13 weeks and 3202±447 *** 90%of both populations had Medicaid *** VLBW infants received care at the Special Care Developmental Follow-Up *** compared with the controls,VLBW infants discharged from the NICU made fewer acute,unscheduled visits to the Emergency Department or Urgent Care Clinic(2.3±2.5 vs.3.7±3.5;P=0.007)despite their high-risk medical and social *** growth pattern showed significant"catch-up"and was similar to the matched controls at the last scheduled visit for each ***:Outcomes including health care utilization in high-risk infants can be improved through meticulous discharge planning and follow-up measures that utilize existing hospital infrastructure to provide affordable comprehensive care.

关键词： health care usage special care clinic very low birth weight

Vision and photoentrainment in fishes: The effects of natural and anthropogenic perturbation

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Integrative Zoology 2015年第1期10卷 15-28页

作者： Shaun P.collin Nathan S.HART School of Animal Biology and the Oceans Institute University of Western AustraliaCrawleyWestern AustraliaAustralia

Vision and photoentrainment in fishes are vital for feeding,avoiding predation,spatial orientation,navigation,social communication and the synchronization of many homeostatic functions such as activity patterns and *** camera-like(image-forming)eyes of fishes are optimized to provide a clear view of their preferred ecological niche,while non-visual photoreceptors provide irradiance detection that mediates circadian photoentrainment,an endogenous time-keeping mechanism(biological clock)to respond to predictable changes in environmental *** and fisheries are under pressure from both natural and anthropogenic perturbation,which in many cases alters the intensity and spectral composition of the light environment on which they depend for their *** review examines the effects of a changing light environment and turbidity on the health of fishes within a developmental and ecological *** the sensory environment of fishes is vital to predicting their responses and,ultimately,their resilience to environmental change and the potential for maintaining sustainable levels of biodiversity.

关键词： circadian rhythms ecology environment photoreception turbidity