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basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: Emphasis on fowl and swine

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动物营养学报 2024年第1期16卷 422-428页

作者： Edwin T. Moran michael R. bedford Poultry Science Department Auburn University AL 36830-5416 USA Ab Vista Woodstock Court Blenheim Road Marlborough Wiltshire SN8 4AN UK

Phytin is the Ca 2+ -Mg 2+ -K + salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca 2+ . Even at low gastric pH, phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca 2+ near the enzyme's active site further stabilizes its newly formed structure. Thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide's basic amino acids; coordinating free Ca 2+ , destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca 2+ and other cations re-bind with accessible anions, phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes (e.g. Ca 2+ , Zn 2+ ) which reduces their structural resistance to autolysis and ability as co-factors (e.g. Zn 2+ ) to increase enzyme activity. Goblet cells initially employ Ca 2+ as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca 2+ is progressively displaced by Na + to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer (USWL). Excessive removal of Ca 2+ from mucin by phytic acid increases its fluidity facilit

关键词： Digestive enzyme Calcium Endogenous protein Mucin Phytin

Resident immune responses to spinal cord injury:role of astrocytes and microglia

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Neural Regeneration Research 2024年第8期19卷 1678-1685页

作者： Sydney brockie Cindy Zhou michael G.Fehlings Division of Genetics and Development Krembil Research InstituteUniversity Health NetworkTorontoONCanada Institute of Medical Science University of TorontoTorontoONCanada Division of Neurosurgery and Spine Program Department of SurgeryUniversity of TorontoTorontoONCanada

Spinal cord injury can be traumatic or non-traumatic in origin,with the latter rising in incidence and prevalence with the aging demographics of our *** r,as the global population ages,individuals with co-existent degenerative spinal pathology comprise a growing number of traumatic spinal cord injury cases,especially involving the cervical spinal *** makes recovery and treatment approaches particula rly challenging as age and comorbidities may limit regenerative *** these reasons,it is critical to better understand the complex milieu of spinal cord injury lesion pathobiology and the ensuing inflammatory *** review discusses microglia-specific purinergic and cytokine signaling pathways,as well as microglial modulation of synaptic stability and plasticity after ***,we evaluate the role of astrocytes in neurotransmission and calcium signaling,as well as their border-forming response to neural *** the inflammatory and reparative roles of these cells have eluded our complete understanding and remain key therapeutic targets due to their extensive structural and functional roles in the nervous *** advances have shed light on the roles of glia in neurotransmission and reparative injury responses that will change how interventions are *** key processes and existing knowledge gaps will allow future research to effectively target these cells and harness their regenerative potential.

关键词： astrocytes glial signaling microglia spinal cord injury synaptic transmission

Centennial Analysis of Human Activity Intensity and Associated Historical Events in Heilongjiang River Sino-Russo Watershed

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Chinese Geographical Science 2024年第2期34卷 280-293页

作者： SONG Chaoxue LI Xiaoling HE Hongshi michael SUNDE School of Geographical Sciences Northeast Normal UniversityChangchun 130024China School of Natural Resources University of MissouriColumbia 65211USA

Human activities in a transborder watershed are complex under the influence of domestic policies,international relations,and global *** the forces driving human activity change is important for the development of transborder *** this study,we used global historical land cover data,the hemeroby index model,and synthesized major historical events to analyze how human activity intensity changed in the Heilongjiang River(Amur River in Russia)watershed(HLRW).The results showed that there was a strong spatial heterogeneity in the variation of human activity intensity in the HLRW over the past century(1900-2016).On the Chinese side,the human activity intensity change shifted from the plain areas for agricultural reclamation to the mountainous areas for timber *** the Russian side,human activity intensity changes mostly concentrated along the Trans-Siberian Railway and the baikal-Amur *** variation of human activity intensity tended to respond to regional events while regionalized variation tends to reflect national policy change or broad international *** similarities and differences between China and Russia in policies and positions in international events resulted in synchronous and asynchronous changes in human activity ***,policy shifts were often confined by the natural features of the *** results reveal the historical origins and fundamental connotations of watershed development and contribute to formulating regional management policies that coordinate population,eco-nomic,social,and environmental activities.

关键词： human activity intensity changes hemeroby index centennial scale Heilongjiang River(Amur River in Russia)watershed China Russia

A Quasi-Linear Relationship between Planetary Outgoing Longwave Radiation and Surface Temperature in a Radiative-Convective-Transportive Climate Model of a Gray Atmosphere

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Advances in Atmospheric Sciences 2024年第1期41卷 8-18页

作者： Jie SUN michael SECOR Ming CAI Xiaoming HU Department of Earth Oceanand Atmospheric ScienceFlorida State UniversityTallahasseeFlorida 32304USA School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Zhuhai 519082China

In this study,we put forward a radiative-convective-transportive energy balance model of a gray atmosphere to examine individual roles of the greenhouse effect of water vapor,vertical convection,and atmospheric poleward energy transport as well as their combined effects for a quasi-linear relationship between the outgoing longwave radiation(OLR)and surface temperature(T_(S)).The greenhouse effect of water vapor enhances the meridional gradient of surface temperature,thereby directly contributing to a quasi-linear OLR-T_(S) *** atmospheric poleward energy transport decreases the meridional gradient of surface *** a result of the poleward energy transport,tropical(high-latitude)atmosphere-surface columns emit less(more)OLR than the solar energy input at their respective locations,causing a substantial reduction of the meridional gradient of the *** combined effect of reducing the meridional gradients of both OLR and surface temperature by the poleward energy transport also contributes to the quasi-linear OLR-T_(S) *** convective energy transport reduces the meridional gradient of surface temperature without affecting the meridional gradient of OLR,thereby suppressing part of the reduction to the increasing rate of OLR with surface temperature by the greenhouse effect of water vapor and poleward energy *** of the nature of the energy balance in the climate system,such a quasi-linear relationship is also a good approximation for the relationship between the annual-mean net downward solar energy flux at the top of the atmosphere and surface temperature.

关键词： outgoing longwave radiation greenhouse effect poleward energy transport

Developing a multi-method approach to identifying e-scooter hazard hotspots

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 667-680页

作者： michael Hardinghaus Simon Nieland Rebekka Oostendorp Jan Weschke German Aerospace Center(DLR)Institute of Transport Research Berlin 12489Germany

In recent years,e-scooters have been introduced in many European *** several places we have witnessed a rapid uptake of this new mode of transport mainly as a result of public sharing schemes.A number of incidents,injuries and even fatalities have given rise to questions regarding the safety of these *** questions are being researched mainly using official crash data and data specifying injuries and hospital *** now,the research has focused on investigating typical injury patterns and estimating risk *** little is known about exactly where conflicts and crashes *** of hazard hotspots is crucial when investigating risk levels and improving safety for all road ***,this paper develops an approach to investigating locations with potentially dangerous interactions within the active mobility system in the city of *** approach consists of explorative expert interviews,an online poll,and quantitative *** the latter we combine three ***,we research crash hotspots using official ***,we use data based on acceleration sensors from cyclists'smartphones to find locations of sudden ***,we use trip data from the operators of escooter sharing *** information gathered is used in a conclusive expert workshop to identify hazard *** show that many of the conflicts with pedestrians are caused by parked ***,e-scooter trips are concentrated in the inner city and along specific *** moving traffic,various data sources are used to identify hotspots at intersections and in areas between *** present research lays the foundation for important further studies to investigate interactions at hotspots in detail by determining nine specific locations in the city of berlin.

关键词： E-scooter Accidents Crashes Active mobility Micromobility Road safety

Multiple sclerosis drug repurposing for neuroregeneration

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Neural Regeneration Research 2024年第3期19卷 507-508页

作者： Peter Göttle michael Dietrich Patrick Küry Department of Neurology Medical FacultyHeinrich-Heine UniversityDüsseldorfGermany

Multiple sclerosis(MS)is an autoimmune disorder of the central nervous system(CNS)and is primarily characterized by immune cell infiltration leading to relapses followed by remission phases and a disease course turning progressive over time with neurodegenerative processes taking over(Amin and Hersh,2023).Of note,beyond relapse-associated worsening early in disease progression independent of relapse activity may arise independently of relapse activity and can occur in all ***-mediated damage of myelin sheaths and the subsequent loss of mature oligodendrocytes are resulting in impaired axonal integrity,neurodegeneration and accounts for irreversible neuronal damage(Kuhlmann et al.,2023).The current landscape of available disease-modifying therapies comprises mainly immunomodulatory drugs that effectively diminish relapses and slow down progression at the onset form of the disease,namely relapsing MS(RMS).In this regard,a number of drugs have been approved as disease-modifying therapies for MS by US Food and Drug Administration and European Medicines Agencies(box 1).

关键词： drugs impaired irreversible

Geometric Programming for Nonlinear Satellite buffer Networks With Time Delays under L_(1)-Gain Performance

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 554-556页

作者： Yukang Cui Yihui Huang michael V.basin Zongze Wu College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China Shenzhen University Shenzhen 518060China Peng Cheng Laboratory Shenzhen 518060China Robotics Institute Ningbo University of TechnologyNingbo 315211China Autonomous University of Nuevo Leon Nuevo Leon 66455Mexico

Dear Editor,This letter concerns the parameter tuning problem for nonlinear satellite buffer networks with communication delays, aiming to optimize their stability properties under L_(1)-gain. We first model the satellite buffer networks by a nonlinear time-delay positive system and propose a novel characterization under which the nonlinear system is asymptotically stable with a prescribed L_(1)-induced performance.

关键词： nonlinear system prescribed

bMPRⅡ^(+)neural precursor cells isolated and characterized from organotypic neurospheres:an in vitro model of human fetal spinal cord development

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Neural Regeneration Research 2024年第2期19卷 447-457页

作者： michael W.Weible II michael D.Lovelace Hamish D.Mundell Tsz Wai Rosita Pang Tailoi Chan-Ling bosch Institute Discipline of Anatomy and Histology(F13)University of SydneySydneyNSWAustralia School of Environment and Science Griffith UniversityNathanQLDAustralia Discipline of Medicine Nepean Clinical SchoolFaculty of Medicine and HealthUniversity of SydneyKingswoodNSWAustralia New South Wales brain Tissue Resource Centre School of Medical SciencesFaculty of Medicine and HealthUniversity of SydneyCharles Perkins Centre(D17)SydneyNSWAustralia

Roof plate secretion of bone morphogenetic proteins(bMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well ***-ⅡbMP receptor(bMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching bMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is *** was undertaken on intact second-trimester human fetal spinal cord using antibodies to bMPRⅡand leukemia inhibitory factor(LIF).Regions of highest bMPRⅡ^(+)immunofluorescence localized to sensory *** and meningeal-associated bMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,CD34/*** immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/CD118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,*** neurospheres were characterized by bMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent *** cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage ***-activated cell sorting-sorted bMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in *** is the first isolation of bMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal *** data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterize

关键词： bMPRⅡ bone morphogenetic protein histotypic human spinal cord development leukemia inhibitory factor neurosphere organotypic reaggregate sensory columns

Low-thermal-budget electrically active thick polysilicon for CMOS-First MEMS-last integration

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Microsystems & Nanoengineering 2024年第3期10卷 395-407页

作者： Aron michael Ian Yao-Hsiang Chuang Chee Yee Kwok Kazuo Omaki UNSW SydneyNSW 2052Australia

Low-thermal-budget,electrically active,and thick polysilicon films are necessary for building a microelectromechanical system(MEMS)on top of a complementary metal oxide semiconductor(CMOS).However,the formation of these polysilicon films is a challenge in this ***,for the first time,the development of in situ phosphorus-doped silicon films deposited under ultrahigh-vacuum conditions(~10^(−9)Torr)using electron-beam evaporation(UHVEE)is *** process results in electrically active,fully crystallized,low-stress,smooth,and thick polysilicon films with low thermal *** crystallographic,mechanical,and electrical properties of phosphorus-doped UHVEE polysilicon films are *** films are compared with intrinsic and boron-doped UHVEE silicon *** spectroscopy,X-ray diffraction(XRD),transmission electron microscopy(TEM)and atomic force microscopy(AFM)are used for crystallographic and surface morphological *** curvature,cantilever deflection profile and resonance frequency measurements are employed to study the mechanical properties of the ***,resistivity measurements are conducted to investigate the electrical properties of the *** vertical,high-aspectratio micromachining of UHVEE polysilicon has been developed.A comb-drive structure is designed,simulated,fabricated,and characterized as an actuator and inertial sensor comprising 20-μm-thick in situ phosphorus-doped UHVEE films at a temperature less than 500℃.The results demonstrate for the first time that UHVEE polysilicon uniquely allows the realization of mechanically and electrically functional MEMS devices with low thermal budgets.

关键词： budget thick thermal