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Integrins and their potential roles in mammalian pregnancy

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Journal of Animal Science and Biotechnology 2024年第1期15卷 1-19页

作者： gregory A.Johnson Robert C.Burghardt Fuller w.Bazer Heew.n Seo Joe w.Cain Department of Veterinary Integrative Biosciences School of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege StationTX 77843‑4459USA Department of Animal Science College of Agriculture and Life SciencesTexas A&M UniversityCollege StationTX 77843‑2471USA

Integrins are a highly complex family of receptors that, w.en expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper w.thin the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins w.re associated w.th the evolution of multicellularity, being essential for the association of cells w.th their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes w.th a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine w.ll, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review.provides a succinct overview.of integrin structure, ligand binding, and signaling follow.d w.th a concise overview.of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, follow.d by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, w.ereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the sc

关键词： Humans Implantation Integrins Pigs Pregnancy Rodents Sheep

Global w.irding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： gregory J.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how.current climatic and biodiversity crises w.ll affect creatures living on land such as ourselves. Perhaps the question is: how.bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible w.rst-case scenario [1].

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A numerical model to simulate the transient frictional viscoelastic sliding contact

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Friction 2024年第2期12卷 319-339页

作者： Dongze w.NG gregory de BOER Anne NEVILLE Ali GHANBARZADEH School of Mechanical Engineering University of LeedsLeeds LS29JTUK

Sliding motion has alw.ys been one of the major concerns w.en it comes to the analysis of viscoelastic contact problems.A new.model simulating the transient sliding contact of smooth viscoelastic surfaces is developed in this *** taking the dry contact friction and the coupling betw.en shear tractions and normal pressure into account,the effect of the early partial slip period,w.ich is often neglected in the study of viscoelastic sliding contact problems,is investigated *** w.th solutions based on the frictionless assumption,the steady-state pressure profile is found to be slightly different under the effect of the partial slip regime,including a low.r peak pressure and the shift of the contacting region in the direction opposite to the sliding ***,the time required for the viscoelastic contact to reach its steady state is delayed ow.ng to the partial slip period preceding the global sliding motion.

关键词： contact mechanics frictional sliding viscoelasticity viscoelastic friction

Trends in oxycodone and oxycodone-containing analgesics administration for back pain in emergency departments in the USA(2007–2018)

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w.rld Journal of Emergency Medicine 2024年第3期15卷 169-174页

作者： Jonathan Chabon Jemer Garrido Deanna Schreiber-gregory Jefferson Drapkin Sergey Motov Department of Emergency Medicine Maimonides Medical CenterBrooklyn 11219USA

BACKGROUND:To describe trends in oxycodone and oxycodone-containing analgesic prescribing for the treatment of back pain among adults in emergency departments(EDs) in the USA from 2007 to ***:Data w.re gathered from the National Hospital Ambulatory Medical Care Survey(NHAMCS) from 2007 to *** study population included individuals of all ages presenting to USA *** NHAMCS reasons for visit and oxycodone drug ID codes w.re used to isolate patients w.th back *** main outcome w.s the proportion of oxycodone and oxycodone-containing analgesics prescribed for back pain in the EDs over the specified time ***:There w.s a relative decrease in the overall administration of oxycodone for back pain in the EDs by 62.3% from 2007(244,000 visits) to 2018(92,000 visits).The proportion of ED patients prescribed w.th oxycodone-containing analgesics for back pain increased among patients aged 45 years and older(from 43.8% to 57.6%),female patients(from 54.5% to 62.0%),black patients(from 22.5% to 30.4%),and Hispanic/Latino patients(from 9.4% to 19.6%).Oxycodone/acetaminophen w.s most prescribed and accounted for 90.2% of all oxycodone-containing analgesics in 2007,w.th a decrease to 68.5% in *** oxycodone w.s the second most prescribed medication,accounting for 6.1% in 2007 and 31.5% in ***:The overall number of oxycodone-containing analgesics decreased significantly from 2007 to ***,that number trended upw.rd in 45-year-old and older,female,black,or Hispanic/Latino patients from 2007 to *** total amount of pure oxycodone increased significantly from 2007 to 2008.

关键词： Oxycodone Back pain Emergency department

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一颗自由进动的磁星

科学通报 2024年第25期69卷 3675-3677页

作者：高勇 gregory Desvignes 邵立晶 Max Planck Institute for Gravitational Physics (Albert Einstein Institute) Max Planck Institute for Radio Astronomy 北京大学科维理天文与天体物理研究所中国科学院国家天文台

磁星是一类具有强磁场和长自转周期的年轻中子星.这些天体极其致密,半径约为12 km,但质量却可达太阳的1～2倍.在已知的30颗磁星中,只有少数会偶尔产生射电辐射.磁星转动时,射电束像灯塔一样扫过天空,天文学家正是从这些规律的脉冲信号...

磁星是一类具有强磁场和长自转周期的年轻中子星.这些天体极其致密,半径约为12 km,但质量却可达太阳的1～2倍.在已知的30颗磁星中,只有少数会偶尔产生射电辐射.磁星转动时,射电束像灯塔一样扫过天空,天文学家正是从这些规律的脉冲信号中探索中子星的奥秘. 2018年末,磁星XTE J1810-197在经历了X射线爆发后再次产生射电辐射,结束了其长达十年的射电静默期.通过长时间、高频次的监测,我们在射电偏振信号中发现射电束相对于地球的倾角发生了显著变化,并且这种变化在几个月内逐渐消失[1].我们认为这种变化是由磁星的自由进动引起的,并提出了衰减的进动模型来解释这一观测现象.这一发现不仅帮助我们更深入地理解了磁星的内部结构和辐射几何,而且很可能排除了自由进动作为重复快速射电暴起源的理论模型.

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High Temperature Iron Ethylene Polymerization Catalysts Bearing N,N,N'-2-(1-(2,4-Dibenzhydryl-6-fluorophenylimino)ethyl)-6-(1-(arylphenylimino)ethyl)pyridines

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Chinese Journal of Polymer Science 2024年第2期42卷 188-201,I0007页

作者： Chantsalnyam Bariashir Qiu-Yue Zhang Bayasgalan Ulambayar gregory A.Solan Tong-Ling Liang w.n-Hua Sun Institute of Chemistry and Chemical Technology Mongolian Academy of SciencesUlaanbaatar13330Mongolia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Chemistry University of LeicesterUniversity RoadLeicesterLE17RHUK State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

The N,N,N'-ferrous chloride complexes,[2-{CMeN(2,4-(CHPh)_(2)-6-FC_(6)H_(2))}-6-(CMeNAr)C_(5)H_(3)N]FeCl_(2)(Ar=2,6-Me_(2)C_(6)H_(3) Fe1,2,6-Et_(2)C_(6)H_(3)Fe2,2,6-^(i)Pr_(2)C_(6)H_(3) Fe3,2,4,6-Me_(3)C_(6)H_(2) Fe4 and 2,6-Et_(2)-4-MeC_(6)H_(2) Fe5),each possessing one N-2,4-dibenzhydryl-6-fluorophenyl group,w.re readily synthesized from their respective unsymmetrical bis(imino)pyridines,*** identification of Fe2 highlighted the variation in the steric properties provided by the dissimilar N-aryl *** pre-treatment w.th either MAO or MMAO,complexes Fe1-Fe5 all displayed,at an operating temperature of 80℃,high activities for ethylene polymerization w.th levels falling in the order:Fe4> Fe1> Fe5> Fe2> ***,Fe4/MAO displayed the highest activity of 1.94×10^(7) g_(PE)·mol_(Fe)^(-1)·h^(-1) of the study w.th only a modest loss in performance at 90℃.Generally,the resulting polyethylenes w.re highly linear(T_(m) range:122-132℃),narrow.y disperse and of low.molecular w.ight(M_(w. range:6.73-46.04kg·mol^(-1)),w.th the most sterically hindered Fe3 forming the highest molecular w.ight polymer of the ***-group analysis by ^(1)H-and ^(13)CNMR spectroscopy revealed saturated alkyl(n-propyl and i-propyl) and unsaturated vinyl chain ends indicative of the role of both β-H elimination and chain transfer to aluminum as termination *** comparison w.th previou sly reported iron precatalysts w.th similar tridentate ligand skeletons,it is evident that the introduction of a large benzhydryl group in combination w.th a fluorine as the ortho-substituents of one N-aryl group has the effect of enhancing thermal stability of the iron polymerization catalyst w.ilst maintaining appreciable polymer molecular w.ight.

关键词： Iron catalyst Ethylene polymerization Linear polyethylene Fluoride effect Thermal stability

PETG:Applications in Modern Medicine

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Engineered Regeneration 2024年第1期5卷 45-55页

作者： Catherine Yan Corinne Kleiner Aaron Tabigue Veer Shah gregory Sacks Darshi Shah Vincent DeStefano Renaissance School of Medicine at Stony Brook University Stony BrookNYUSA Department of Biology Niagara UniversityLewistonNYUSA Stony Brook University Stony BrookNYUSA Department of Mechanical and Industrial Engineering Northeastern UniversityBostonMAUSA

Polyethylene terephthalate glycol,PETG,is a miscible,transparent thermoplastic know. to have strong tensile properties,high ductility,as w.ll as resistance to heat and chemical *** may be manufactured in several w.ys,most notably 3D printing *** such,PETG has emerged as a viable biomaterial for a variety of medical applications such as tissue engineering,dentistry,optometry,vascular health,cardiology,orthopedics,neurology,gynecology,and *** also serves a valuable role in biomedical research and engineering by offering improvements in cell studies,drug carriers,and anti-bacterial *** medical research and innovation utilizing PETG w.ll better characterize its value as an inexpensive and versatile biomaterial.

关键词： Polyethylene terephthalate glycol Tissue Engineering 3D Printing Clinical Applications Biomedical Research

Applying Earth Observation Technologies to Economic Consequence Modeling:A Case Study of COVID‑19 in Los Angeles County,California

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International Journal of Disaster Risk Science 2024年第1期15卷 18-31页

作者： Fynnw.n Prager Marina T.Mendoza Charles K.Huyck Adam Rose Paul Amyx gregory Yetman Kristy F.Tiampo California State University Dominguez HillsCarsonCA 90747USA ImageCat Inc.Long BeachCA 90802USA University of Southern California Los AngelesCA 90015USA CIESIN–Center for International Earth Science Information Netw.rk Columbia UniversityPalisadesNY 10964USA Cooperative Institute for Research in Environmental Sciences(CIRES) University of Colorado BoulderBoulderCO 80309USA

Earth observation(EO) technologies,such as very high-resolution optical satellite data available from Maxar,can enhance economic consequence modeling of disasters by capturing the fine-grained and real-time behavioral responses of businesses and the *** investigated this unique approach to economic consequence modeling to determine w.ether crow.-sourced interpretations of EO data can be used to illuminate key economic behavioral responses that could be used for computable general equilibrium modeling of supply chain repercussions and resilience *** applied our methodology to the COVID-19 pandemic experience in Los Angeles County,California as a case *** also proposed a dynamic adjustment approach to account for the changing character of EO through longer-term disasters in the economic modeling *** found that despite limitations,EO data can increase sectoral and temporal resolution,w.ich leads to significant differences from other data sources in terms of direct and total impact *** findings from this analytical approach have important implications for economic consequence modeling of disasters,as w.ll as providing useful information to policymakers and emergency managers,w.ose goal is to reduce disaster costs and to improve economic resilience.

关键词： Computable general equilibrium models COVID-19 Disaster economic impacts Earth observation Economic consequence analysis Los Angeles County

A functional tacrolimus-releasing nerve w.ap for enhancing nerve regeneration follow.ng surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn J.w.So Konstantin Feinberg Marina Manoraj Jenny Cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa Gordon gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration follow.ng surgical nerve repair is slow.and often incomplete,resulting in poor functional recovery w.ich sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outw.igh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,w.th suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery w.th minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve w.ap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the w.ap degrades w.thin 120 days into biocompatible *** released from the nerve w.ap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models w.ile off-target systemic drug exposure is reduced by 80%compared w.th systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve w.ap tacrolimus