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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

Cell-cell interactions and communication dynamics in lung fibrosis

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Chinese Medical journal Pulmonary and Critical Care Medicine 2024年第2期2卷 63-71页

作者： Ting Xie jiurong Liang barry stripp Paul W.Noble Division of Pulmonary and Critical Care Medicine Department of MedicineWomen’s Guild Lung InstituteCedars-Sinai Medical CenterLos AngelesCA 90048USA

Cell-cell interactions are essential components of coordinated cell function in lung *** diseases involve altered cell-cell interactions and communication between different cell types,as well as between subsets of cells of the same *** identification and understanding of intercellular signaling in lung fibrosis offer insights into the molecular mechanisms underlying these interactions and their implications in the development and progression of lung fibrosis.A comprehensive cell atlas of the human lung,established with the facilita-tion of single-cell RNA transcriptomic analysis,has enabled the inference of intercellular communications using ligand-receptor *** this review,we provide a comprehensive overview of the modified cell-cell commu-nications in lung *** highlight the intricate interactions among the major cell types within the lung and their contributions to *** insights presented in this review will contribute to a better understand-ing of the molecular mechanisms underlying lung fibrosis and may guide future research efforts in developing targeted therapies for this debilitating disease.

关键词： Cell–cell interaction Lung fibrosis Lung homeostasis Targeted therapies

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

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

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.

Escherichia coli-host macrophage interactions in the pathogenesis of inflammatory bowel disease

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World journal of Gastroenterology 2014年第27期20卷 8751-8763页

作者： Ahmed Tawfik Paul K Flanagan barry j Campbell Department of Gastroenterology Institute of Translational Medicine University of Liverpool

Multiple studies have demonstrated alterations in the intestinal microbial community (termed the microbiome) in Crohn’s disease (CD) and several lines of evidence suggest these changes may have a significant role in disease pathogenesis. In active and quiescent disease, both the faecal and mucosa-associated microbiome are discordant with matched controls with reduced biodiversity, changes in dominant organisms and increased temporal variation described. Mucosa-associated adherent, invasive Escherichia coli (E. coli) (AIEC), pro-inflammatory and resistant to killing by mucosal macrophages, appear to be particularly important. AIEC possess several virulence factors which may confer pathogenic potential in CD. Type-1 pili (FimH) allow adherence to intestinal cells via cell-surface carcinoembryonic antigen-related cell adhesion molecules and possession of long polar fimbrae promotes translocation across the intestinal mucosa via microfold (M)-cells of the follicle-associated epithelium. Resistance to stress genes (htrA, dsbA and hfq) and tolerance of an acidic pH may contribute to survival within the phagolysosomal environment. Here we review the current understanding of the role of mucosa-associated E. coli in Crohn’s pathogenesis, the role of the innate immune system, factors which may contribute to prolonged bacterial survival and therapeutic strategies to target intracellular E. coli.

关键词： Crohn's disease Inflammatory bowel disease Escherichia coli Intra-macrophage survival and replication Phagolysosome Autophagy

Road induced edge effects on a forest bird community in tropical Asia

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Avian Research 2018年第2期9卷 123-135页

作者： Daphawan Khamcha Richard T.Corlett Larkin A.Powell Tommaso savini Antony j.Lynam George A.gale Conservation Ecology Program School of Bioresources and Technology King Mongkut’s University of Technology Thonburi Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences school of Natural Resources University of Nebraska-Lincoln Wildlife Conservation society Global Conservation Program

Background: Edge effects cause changes in bird community richness, abundance, and/or distribution within a landscape, but the avian guilds most influenced can vary among regions. Although southeast Asia has the highest rates of deforestation and projected species loss, and is currently undergoing an explosive growth in road infrastructure, there have been few studies of the effects of forest edges on avian communities in this ***: We examined avian community structure in a dry evergreen forest in northeastern Thailand adjacent to a five-lane highway. We evaluated the richness and abundance of birds in 11 guilds at 24 survey points on three parallel transects perpendicular to the edge. At each point, 10-min surveys were conducted during February-August 2014 and March-August 2015. Vegetation measurements were conducted at 16 of the bird survey points and ambient noise was measured at all 24 survey ***: We found a strongly negative response to the forest edge for bark-gleaning, sallying, terrestrial, and understory insectivores and a weakly negative response for arboreal frugivore-insectivores, foliage gleaning insectivores, and raptors. Densities of trees and the percentage canopy cover were higher in the interior, and the ambient noise was lower. In contrast, arboreal nectarivore-insectivores responded positively to the forest edge, where there was a higher vegetation cover in the ground layer, a lower tree density, and a higher level of ambient ***: Planners should avoid road development in forests of high conservation value to reduce impacts on biodiversity. Where avoidance is impossible, a number of potential mitigation methods are available, but more detailed assessments of these are needed before they are applied in this region.

关键词： Road edge Avian guilds Dry evergreen forest Thailand

A preliminary study of sperm identification in microdissection testicular sperm extraction samples with deep convolutional neural networks

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Asian journal of Andrology 2021年第2期23卷 135-139页

作者： Daniel j Wu Odgerel Badamjav Vikrant V Reddy Michael Eisenberg barry Behr Department of Computer science Stanford UniversityStanfordCA 94305USA Department of Urology University of Utah HealthSalt Lake CityUT 84108USA Department of Obstetrics and Gynecology Stanford Children’s HealthStanfordCA 94305USA Department of Urology Stanford University School of MedicineStanfordCA 94305USA

sperm identification and selection is an essential task when processing human testicular samples for in vitro *** and identifying sperm cell(s)in human testicular biopsy samples is labor intensive and time *** developed a new computer-aided sperm analysis(CAsA)system,which utilizes deep learning for near human-level performance on testicular sperm extraction(TEsE),trained on a custom *** system automates the identification of sperm in testicular biopsy samples.A dataset of 702 de-identified images from testicular biopsy samples of 30 patients was *** image was normalized and passed through glare filters and diffraction *** data were split 80%,10%,and 10%into training,validation,and test sets,***,a deep object detection network,composed of a feature extraction network and object detection network,was trained on this *** model was benchmarked against embryologists’performance on the detection *** deep learning CAsA system achieved a mean average precision(mAP)of 0.741,with an average recall(AR)of 0.376 on our *** proposed method can work in real time;its speed is effectively limited only by the imaging speed of the *** results indicate that deep learning-based technologies can improve the efficiency of finding sperm in testicular biopsy samples.

关键词： artificial intelligence computer vision male infertility microdissection testicular sperm extraction sperm