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Chinese science Bulletin 2008年第5期53卷 642-651页

作者： sUN jingHua barry j s gale Derryck T Reid Ultrafast Optics Group School of Engineering and Physical Sciences Heriot-Watt University Edinburgh EH14 4AS UK Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The intrinsic synchronization, multi-color outputs and related carrier-envelope phases (CEP) among pulses bring advantages to synchronously pumped femtosecond optical parametric oscillators and the pumping sources for broadband frequency comb generation and ultrashort waveform coherent syn-thesis. In this paper, we discuss our latest research results in this field, which cover the following as-pects: the phase relationship and energy conservation law in an OPO and related experimental verifi-cation; control of the pumping Ti:sapphire femtosecond laser's CEP by self-referencing technology, and its repetition-rate locking by piezoelectric transducer (PZT); CEP locking of the pulses from the OPO by beating the non-phase-matched visible outputs against pump supercontinuum to obtain a driving signal for a fast PZT on the OPO end mirror; the generation of a broadband frequency comb spanning from 400 nm to 2.4 μm with 1.2 kHz bandwidth; and the realization of coherent interference between phase controlled pump pulses and signal second harmonic pulses.

关键词：光学参数振荡器载波包络相同步控制超短光脉冲

Fetal Head Compression: Its Possible Role in Neurologic Injury

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Open journal of Obstetrics and Gynecology 2024年第1期14卷 124-143页

作者： barry s. schifrin Brian j. Koos Wayne R. Cohen Department of Obstetrics and Gynecology The Western University of Health Sciences Pomona USA The David Geffen school of Medicine at UCLA Los Angeles USA The University of Arizona College of Medicine Tucson USA

It is widely assumed that fetal ischemic brain injury during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. severe asphyxia, however, is one of several causes of perinatal neurological injury and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of severe asphyxia. sepsis, direct brain trauma, and drug or toxin exposure account for some cases, while mechanical forces of labor and delivery that increase fetal intracranial pressure sufficiently to impair brain perfusion may also contribute. Because of bony compliance and mobile suture lines, the fetal skull changes shape and redistributes cerebrospinal fluid during labor according to constraints imposed by contractions, and bony and soft tissue elements of the birth canal as the head descends. These accommodations, including the increase in intracranial pressure, are adaptive and necessary for efficient descent of the head while safeguarding cerebral blood flow. Autonomic reflexes mediated through central receptors normally provide ample protection of the brain from the considerable pressure exerted on the skull. On occasion, those forces, which are transmitted intracranially, may overcome the various adaptive anatomical, cardiovascular, metabolic, and neurological mechanisms that maintain cerebral perfusion and oxygen availability, resulting in ischemic brain injury. Accepting the notion of a potentially adverse impact of fetal head compression suggests that avoidance of excessive uterine activity and of relentless pushing without steady progress in descent may offer protection for the fetal brain during parturition. Excessive head compression should be considered in the differential diagnosis of ischemic encephalopathy.

关键词： Fetal Brain Injury Fetal Head Compression Ischemic Encephalopathy Neonatal Encephalopathy

Investigation of HCAR2 antagonists as a potential strategy to modulate bovine leukocytes

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journal of Animal science and Biotechnology 2024年第4期15卷 1567-1577页

作者： Laman K.Mamedova Kirby C.Krogstad Paiton O.McDonald Laxman Pokhrel Duy H.Hua Evan C.Titgemeyer barry j.Bradford Department of Animal science Michigan State UniversityEast LansingMichigan 48824USA Department of Animal sciences and Industry Kansas State UniversityManhattanKS 66506USA Comparative Medicine and Integrative Biology East LansingMI 48824USA Department of Chemistry Kansas State UniversityManhattanKS 66506USA

Background Dairy cows experiencing ketosis after calving suffer greater disease incidence and are at greater risk of leaving the herd. In vitro administration of beta-hydroxybutyric acid(BHBA;the primary blood ketone) has inhibitory effects on the function of bovine leukocytes. BHBA is a ligand of HCAR2 and the activation of these receptors promotes an anti-inflammatory response which may be related with immunosuppression observed in transition dairy cattle. The objective of this study was to identify and test antagonists for HCAR2 in bovine immune cells cultured with *** We observed expression of HCAR2 at the protein level within lymphocytes, monocytes, and granulocytes. The proportion of cells expressing HCAR2 tended to be greater in mid-lactation compared to early lactation cows;the increase was a result of increased proportion of T and B cells expressing HCAR2. stimulation of HCAR2 with niacin or BHBA promoted Ca^(2+) mobilization in neutrophils and mononuclear cells. Mononuclear cells treated with BHBA had diminished intracellular Ca^(2+) responses when HCAR2 was knocked down by si RNA silencing, indicating Ca^(2+) mobilization was mediated by HCAR2 signaling. Two candidate antagonists for HCAR2, synthesized from niacin(NA-1 and NA-5), were tested;monocytes and neutrophils pre-treated with NA-1 and NA-5 had reduced Ca^(2+) mobilization after incubation with BHBA. Furthermore, NA-5 but not NA-1 prevented BHBA-associated reductions in cyclic *** We demonstrated that HCAR2 is present on bovine leukocytes and has greater expression later in lactation. We confirmed that BHBA and niacin derived HCAR2 antagonists alter bovine leukocyte activity. Our results demonstrate that both BHBA and niacin affect bovine leukocyte Ca^(2+) mobilization in a HCAR2-dependent manner.

关键词： Flow cytometry GPR109A HM74A Ketosis

Predicting an Athlete’s Physiological and Haematological Response to Live High-Train High Altitude Training Using a Hypoxic sensitivity Test

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journal of science in sport and Exercise 2022年第4期4卷 371-385页

作者： Gareth Turner Kate L.spilsbury David j.Green barry W.Fudge jamie s.M.Pringle Alan j.Richardson Neil s.Maxwell Environmental Extreme Laboratory University of BrightonEastbourneUK English Institute of sport Bisham AbbeyUK Queensland Academy of sport BrisbaneAustralia English Institute of sport LoughboroughUK Aspire Academy DohaQatar University of Birmingham BirminghamUK

Purpose Elite endurance runners frequently utilise live high-train high(LHTH)altitude training to improve endurance per-formance at sea level(sL).Individual variability in response to the hypoxic exposure have resulted in contradictory *** the present case study,changes in total haemoglobin mass(tHbmass)and physiological capacity,in response to 4-weeks of LHTH were *** tested if a hypoxic sensitivity test(HsT)could predict altitude-induced adaptations to *** Fifteen elite athletes were selected to complete 4-weeks of LHTH(~2400 m).Athletes visited the laboratory for preliminary testing(PRE),to determine lactate threshold(LT),lactate turn point(LTP),maximal oxygen uptake VO_(2max)and *** LHTH,athletes completed daily physiological measures[arterial oxygen saturation(spO2)and body mass]and subjective wellbeing *** was repeated,for those who completed the full camp,post-LHTH(POsT).Additionally,athletes completed the HsT prior to *** A difference(Ps found from PRE to POsT in average tHbmass(1.8%±3.4%),VO_(2max)(2.7%±3.4%),LT(6.1%±4.6%)and LTP(5.4%±3.8%),after 4-weeks *** revealed a decrease in oxygen saturation at rest(Δsp_(r))and higher hypoxic ventilatory response at rest(HVRr)predicted individual changes *** hypoxic cardiac response at rest(HCRr)and higher HVRr predicted individual changes VO_(2max).Conclusion Four weeks of LHTH at~2400 m increased tHbmass and enhanced physiological capacity in elite endurance *** was no observed relationship between these changes and baseline characteristics,pre-LHTH serum ferritin levels,or reported incidents of musculoskeletal injury or *** HsT did however,estimate changes in tHbmass and VO_(2max).HsT prior to LHTH could allow coaches and practitioners to better inform the acclimatisation strategies and train-ing load application of endurance runners at altitude.

关键词： Altitude training Runners Endurance Haemoglobin mass Performance Hypoxic sensitivity

The Global Boundary stratotype section and Point （GssP） for the base of the Cenomanian stage, Mont Risou, Hautes-Alpes, France

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Episodes 2004年第1期27卷 21-32页

作者： W.j.Kennedy A.s.gale j.A.Lees M.Caron OxfordUniversityMuseumofNaturalHistory ParksRoadOxfordOXI3PWU.K. DepartmentofPalaeontology TheNaturalHistoryMuseumCromwellRoadLondonSW75BPU.K.andSchoolofEarthandEnvironmentalSciencesUniversityofGreenwichChathamMaritimeCampusChathamKentME44AWU.K. ResearchschoolofGeologicalandGeophysicalsciences BirkbeckCollegeandUniversityCollegeLondonGowerStreetLondonWCIE6BTU.K. InstitutdeGeologie UniversitedeFribourgCH-1700FribourgSwitzerland.

Following the unanimous recommendation of the International Commission on stratigraphy, the Global boundary stratotype section and Point (GssP) for the base of the Cenomanian stage is defined at a level 36 metres below the top of the Marnes Bleues Formation, a level that corresponds to the the first appearance of the planktonic foraminiferan Rotalipora globotruncanoides sigal, 1948, on the south side of Mont Risou, east of Rosans, Haute-Alpes, France, where it can be placed in the context of a series of secondary marker levels based on nannofossils, planktonic foraminifera, ammonites,and an ornate δ^13C curve.

关键词：地层学地层分界线层型地质构造

Changes in otolaryngology application requirements and match outcomes:Are we doing any better?

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World journal of Otorhinolaryngology-Head and Neck surgery 2023年第2期9卷 144-152页

作者： Emma De Ravin Ariel s.Frost Neal R.Godse Amber D.shaffer Noel jabbour barry M.schaitkin jason Newman Leila j.Mady Department of Otorhinolaryngology-Head and Neck surgery University of Pennsylvania Health SystemPhiladelphiaPennsylvaniaUSA Head and Neck Institute Cleveland ClinicClevelandOhioUSA Division of Pediatric Otolaryngology Children's Hospital of Pittsburgh of UPMCPittsburghPennsylvaniaUSA Department of Otolaryngology University of Pittsburgh Medical CenterPittsburghPennsylvaniaUSA Department of Otolaryngology-Head and Necksurgery Medical Universityof South CarolinaCharlestonSouth CarolinaUSA MUsC Hollings Cancer Center CharlestonSouthCarolinaUSA Department of Otolaryngology-Head and Neck surgery Thomas Jefferson UniversityPhiladelphiaPennsylvaniaUSA Cancer Risk and Control Program of Excellence Sidney Kimmel Cancer CenterPhiladelphiaPennsylvaniaUSA

Objectives:Otolaryngology-specific requirements were piloted to minimize applicant and program *** investigated the impact of introducing and then removing these requirements on Match ***:2014-2021 National Resident Matching Program?data were *** primary outcome was the impact of Otolaryngology Resident Talent Assessment(ORTA;prematch 2017,postmatch 2019)and Program-specific Paragraph(PsP;implemented 2016,optional 2018)on applicant numbers and match *** survey analysis assessed candidate perceptions of PsP/***:Applicant numbers declined significantly during PsP/ORTA(18.9%;p=0.001).With the optional PsP and postmatch ORTA,applicant numbers increased significantly(39.0%;p=0.002).Examined individually,mandatory PsP was associated with a significant decline in applicants(p=0.007),whereas postmatch ORTA was associated with significant increases in applicants(p=0.010).ORTA and PsP negatively impacted the decision to apply to otolaryngology in 59.8%and 51.3%of applicants,***,match rate success improved significantly from 74.8%to 91.2%during PsP/ORTA(p=0.014),followed by a significant decline to 73.1%after PsP was made optional and ORTA moved to postmatch(p=0.002).Conclusions:ORTA and PsP correlated with decreased applicant numbers and increased match rate *** programs seek ways to remove barriers to applying to otolaryngology,the potential consequences of an increasing pool of unmatched candidates must also be considered.

关键词： academic success internship and residency medical students otolaryngology surveys and questionnaires

Plant-frugivore interactions in an intact tropical forest in north-east Thailand

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Integrative Zoology 2011年第3期6卷 195-212页

作者： Wangworn sANKAMETHAWEE Andrew j.PIERCE George A.gale Britta Denise HARDEsTY Conservation Ecology Program School of Bioresources and TechnologyKing Mongkut’s University of Technology ThonburiBangkok Thailand Walai Rukhavej Botanical Research Institute Mahasarakham UniversityMahasarakhamThailand CsIRO Ecosystem sciences AthertonQueenslandAustralia

Fleshy-fruited plants in tropical forests largely rely on vertebrate frugivores to disperse their *** this plant-animal interaction is typically considered a diffuse mutualism,it is fundamental as it provides the template on which tropical forest communities are *** applied a mutualistic network approach to investigate the relationship between small-fruited fleshy plant species and the fruit-eating bird community in an intact evergreen forest in north-east Thailand.A minimum of 53 bird species consumed fruits of 136 plant ***-avian frugivore networks were highly asymmetrical,with observed networks filling 30%of all potential *** some of the missing links in the present study might be due to undersampling,forbidden links can be attributed to size constraints,accessibility and phenological uncoupling,and although the majority of missing links were unknown(58.2%),many were probably due to a given bird species being either rare or only a very occasional fruit *** most common frugivores were bulbuls,barbets and fairy-bluebirds,which were responsible for the majority of fruit removal from small fleshy fruited species in our *** birds seemed to be a minor component of the plant-frugivore networks,accounting for only 3%of feeding visits to fruiting trees;they filled 2%of the overall potential *** majority of interactions were generalized unspecific;however,saurauia roxburghii *** to be dependent on flowerpeckers for dispersal,while Thick-billed Pigeons were only seen to eat figs.

关键词： avian frugivore nestedness plant-frugivore networks seed dispersal tropical forest

Multi-Institutional Us Experience of the Occlutech AFR Device in Congenital and Acquired Heart Disease

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Congenital Heart Disease 2022年第1期17卷 107-116页

作者： barry O’Callaghan jenny Zablah joseph Vettukattil Daniel Levi Morris salem Allison Cabalka jason Anderson Makram Ebeid Ryan Alexy Gareth j.Morgan The Heart Institute Children’s Hospital ColoradoAuroraUSA Pediatric Cardiology Helen DeVos Children’s HospitalGrand RapidsUSA Pediatric Cardiology UCLA HealthMattel Children’s HospitalLos AngelesUSA Pediatric Cardiology UCLA Medical CentreLos AngelesUSA Pediatric Cardiology Mayo ClinicRochesterUSA Pediatric Cardiology University of Mississippi Medical CenterJacksonUSA Pediatric Cardiology Riley Hospital for Children at Indiana University HealthIndianapolisUSA

Objectives:To detail the Us multi-institutional experience with the Occlutech©(Occlutech International AB,Helsingborg,sweden)atrial flow regulator(AFR)in children and adults with acquired or congenital heart ***:The creation of a long-term atrial communication is desirable in several cardiovascular disease phenotypes,most notably pulmonary arterial hypertension,disorders of increased left ventricular filling and increased cavopulmonary pressures in patients with a Fontan type ***:Patients were identified for inclusion from the AFR device manufacturer *** was collected using a RedCap database following IRB approval.8 weeks of follow up data was sought for each patient based on available *** was analyzed and summarized using ***:We report the experience of 6 Us centers in the implantation of AFR devices in 15 patients,across a wide age range,with different disease phenotypes and a variety of *** was technically successful in all patients and improvement was noted in both clinical and hemodynamic *** were no immediate or intermediate term complications reported.3 patients died remote from *** deaths were not felt to be related to the AFR device or related procedural ***:Compassionate use of the AFR device in children and adults with congenital&acquired heart disease is technically feasible and produces beneficial short term hemodynamic and symptomatic *** uptake of this technique and treatment at specialist centers has the potential to provide significant benefits to a variety of complex patients with currently limited treatment options and indeterminate prognosis.

关键词： Congenital heart disease pulmonary hypertension left atrial hypertension single ventricle palliation diastolic heart failure

Histone Acetylation, VERNALIZATION INsENsITIVE 3, FLOWERING LOCUs C, and the Vernalization Response

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Molecular Plant 2009年第4期2卷 724-737页

作者： Donna M. Bond Elizabeth s. Dennis barry j. Pogson E. jean Finnegan CsIRO Plant Industry Canberra Australia ARC Centre of Excellence in Plant Energy Biology School of Biochemistry and Molecular Biology Australian National University Canberra Australia

The quantitative induction of VIN3 by low temperatures is required for PRC2 repression of FLC and promotion of flowering （vernalization） in Arabidopsis. Histone acetylation, a chromatin modification commonly associated with gene transcription, increased on VIN3 chromatin in two spatially and temporally distinct phases in response to low temperatures. During short-term cold exposure, histone H3 acetylation at the transcription start site rapidly increased, implying that it is required for VlN3 induction. subsequent changes in histone H3 and H4 acetylation occurred following continued VIN3 transcription during prolonged cold exposure. Members of the sAGA-like transcriptional adaptor complex, including the histone acetyltransferase GCNs, which induces expression of the cold acclimation pathway genes, do not regulate VlN3 induction during cold exposure, indicating that the cold acclimation pathway and the cold-induction of VlN3 are regulated by different transcriptional mechanisms. Mutations in the other 11 histone acetyltransferase genes did not affect VlN3 induction. However, nicotinamide, a histone deacetyiase inhibitor, induced VIN3 and altered histone acetylation at the VIN3 locus. VIN3 induction was proportional to the length of nicotinamide treatment, which was associated with an early-flowering phenotype and repression of FLC. However, unlike vernalization, the repression of FLC was independent of VIN3 activity. Nicotinamide treatment did not cause a change in the expression of any genes in the autonomous pathway or members of the PRC2 complex, the well characterized repressors of FLC. Our data suggest that FLC is repressed via a novel pathway involving the sIR2 class of histone deacetylases.

关键词： Cold acclimation histone acetyltransferase histone deacetylase sIR2 nicotinamide.

A new academic impact metric for evaluating geographic simulation models

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International journal of Digital Earth 2022年第1期15卷 1855-1880页

作者： Kai Xu Min Chen Albert j.Kettner C.Michael Barton barry F.W.Croke Anthony j.jakeman Daniel P.Ames Hsiao-Hsuan Wang susan M.Cuddy songshan Yue Yongning Wen Fengyuan Zhang Yixuan Zhang Guonian Lü Key Laboratory of Virtual Geographic Environment (Ministry of Education of PRC) Nanjing Normal UniversityNanjingJiangsuPeople’s Republic of China jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application NanjingJiangsuPeople’s Republic of China state Key Laboratory Cultivation Base of Geographical Environment Evolution(jiangsu Province) NanjingJiangsuPeople’s Republic of China Community surface Dynamics Modelling system (CsDMs) Institute of Arctic and Alpine Research (INSTAAR)University of ColoradoBoulderCOUSA school of Human Evolution and social Change Arizona State UniversityTempeAZUSA school of Complex Adaptive systems Arizona State UniversityTempeAZUSA Institute for Water Futures Fenner School of Environment and SocietyAustralian National UniversityCanberraAustralia Mathematical sciences Institute The Australian National UniversityCanberraAustralia Department of Civil and Construction Engineering Brigham Young UniversityProvoUTUSA Ecological systems Laboratory Department of Ecology and Conservation BiologyTexas A&M UniversityCollege StationTXUSA CsIRO Land and Water CanberraAustralia

Geographic simulation models can be used to explore and better understand the geographical environment. Recent advances in geographic and socio-environmental research have led to a dramatic increase in the number of models used for this purpose. some model repositories provide opportunities for users to explore and apply models,but few provide a general evaluation method for assessing the applicability and recognition of models. In this study,an academic impact evaluation method for models is proposed. Five indices are designed based on their pertinence. The analytical hierarchy process is used to calculate the index weights,and the academic impacts of models are quantified with the weighted sum method. The time range is controlled to evaluate the life-term and annual academic impacts of the models. some models that met the evaluation criteria from different domains are then evaluated. The results show that the academic impact of a model can be quantified with the proposed method,and the major research areas that models impact are identified.

关键词： Geographic simulation model academic impact analytic hierarchy process model impact evaluation