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Premature axon-oligodendrocyte interaction contributes to stalling of experimental axon regeneration after injury to the white matter

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Neural Regeneration Research 2024年第3期19卷 469-470页

作者： Ephraim f.Trakhtenberg Department of Neuroscience University of Connecticut School of MedicineFarmingtonCTUSA

studies from nearly 3 decades ago suggested that,in the central nervous system(CNs),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been found to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,semaphorins)(Yiu and He,2006;silver et al.,2014).After white matter injury in the adult CNs,myelin debris from damaged axons and dead oligodendrocytes accumulates in the forming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of axonal *** development,CNs axons reach their postsynaptic targets and stop growing before oligodendrocytes appear and myelinate them(foran and Peterson,1992;Dangata et al.,1996).Therefore,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons from promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the CNs(Colello and schwab,1994).

关键词： thereby white injury

An unexpected cellular fountain of youth:platelets provide factors rejuvenating brain functions

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signal Transduction and Targeted Therapy 2024年第1期9卷 16-18页

作者： Harald f.Langer Department of Cardiology AngiologyHaemostaseology and Medical Intensive CareUniversity Medical Centre MannheimMedical Faculty MannheimHeidelberg UniversityMannheimGermany German Centre for Cardiovascular Research(DZHK) Partner Site Heidelberg/MannheimMannheimGermany European Center for Angioscience Medical Faculty MannheimHeidelberg UniversityMannheimGermany Cardiovascular systems biology Medical Clinic IUniversity Heart Center LübeckLübeckGermany

In a recent manuscript published in Nature,schroer et *** that platelets and in particular platelet derived Pf-4(CXCL4)are a novel factor,which can rejuvenate the mammalian neuronal system.1 These findings have the potential to trigger an entire new field of research opening new platelet-derived candidate effector molecules for supporting regeneration.

关键词： supporting platelets finding

Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on si(111) substrates

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Journal of semiconductors 2024年第9期45卷 28-35页

作者： Leonarde N.Rodrigues Wesley f.Inoch Marcos L.f.Gomes Odilon D.D.Couto Jr. Bráulio s.Archanjo sukarno O.ferreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

Modelling the unexpected dynamics of COVID-19 in Manaus,Brazil

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Infectious Disease Modelling 2024年第2期9卷 557-568页

作者： Daihai He Yael Artzy-Randrup salihu s.Musa Tiago Gräf felipe Naveca Lewi stone Department of Applied Mathematics Hong Kong Polytechnic UniversityHong Kong SARChina Department of Theoretical and Computational Ecology IBEDUniversity of AmsterdamAmsterdamNetherlands Department of Genomics and Computational Biology University of Massachusetts Chan Medical SchoolWorcesterMA01605USA Department of Mathematics Aliko Dangote University of Science and TechnologyKanoNigeria Instituto Gonçalo Moniz FiocruzSalvadorBahiaBrazil Instituto Leônidas e Maria Deane FiocruzManausBrazil Mathematical sciences School of ScienceRMIT UniversityMelbourneAustralia Biomathematics Unit School of ZoologyFaculty of Life SciencesTel Aviv UniversityTel AvivIsrael

In late March 2020,sARs-CoV-2 arrived in Manaus,Brazil,and rapidly developed into a large-scale epidemic that collapsed the local health system and resulted in extreme death *** key studies reported that∼76%of residents of Manaus were infected(attack rate AR≃76%)by October 2020,suggesting protective herd immunity had been *** this,an unexpected second wave of COVID-19 struck again in November and proved to be larger than the first,creating a catastrophe for the unprepared *** has been suggested that this could be possible if the second wave was driven by ***,it is widely reported that reinfections were at a low rate(before the emergence of Omicron),and reinfections tend to be ***,we use novel methods to model the epidemic from mortality data without considering reinfection-caused deaths and evaluate the impact of interventions to explain why the second wave *** method fits a“flexible”reproductive numberR_(0)(t)that changes over the epidemic,and it is demonstrated that the method can successfully reconstruct R_(0)(t)from simulated *** Manaus,the method finds AR≃34%by October 2020 for the first wave,which is far less than required for herd immunity yet in-line with seroprevalence *** work is complemented by a two-strain *** genomic data,the model estimates transmissibility of the new P.1 virus lineage as 1.9 times higher than that of the ***,an age class model variant that considers the high mortality rates of older adults show very similar *** models thus provide a reasonable explanation for the two-wave dynamics in Manaus without the need to rely on large reinfection rates,which until now have only been found in negligible to moderate numbers in recent surveillance efforts.

关键词： Modelling COVID-19 Reproduction number Herd immunity Reinfection

Assessment of CO_(2)storage prospect based on physical properties of Rio Bonito formation rock units

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Energy Geoscience 2024年第1期5卷 321-330页

作者： Richardson M.Abraham-A stephanie san Martín Cañas Isabella f.s.Miranda Colombo C.G.Tassinari Institute of Energy and Environment(IEE) University of São Paulo(USP)Brazil Research Centre for Greenhouse Gas Innovation(RCGI) University of Sãao Paulo(USP)Brazil

The physical properties of the rock units associated with the Rio Bonito formation are presented in this study with the focus on modelling reservoir quality based on petrophysics-derived parameters to evaluate CO_(2)storage *** involves the modelling of the reservoir depths,thicknesses,flow zone indicators(fZI),and effective permeability(Keff)and presenting the CO_(2)storage efficiency factors peculiar to the rock units of the study *** results presented by this study for the stated objectives are not quite common in the *** values range from 200 mD to higher than 2000 mD,and fZI values are generally above 1.0 mm and up to 13.0 mm within the portions covered by the drilled *** sandstone units recorded are up to 20 m thick in some *** Keff and fZI models indicate the sandstone reservoirs as permeable units to support the injection and circulation of CO_(2)within the potential reservoir units of the Rio Bonio formation across são Paulo *** from some points in the southeastern part of the study location,where the Rio Bonito are delineated at depths less than 800 m(minimum CO_(2)storage depth based on best practices),other portions are deeper,ranging from 950 m to 3500 ***-bedded layers will affect the integrity of the rocks as CO_(2)storage tanks or reservoir seals/traps/overburden within the *** bed thicknesses are up to 20 m in some ***,hybrid CO_(2)reservoir units are feasible,especially in portions where thin siltstone layers are sandwiched between sandstone units to provide considerable thicknesses based on CO_(2)storage *** current study shows that useable areas considering reservoir thickness,depth,and other physical qualities will significantly control the CO_(2)storage efficiency of the study *** studies featuring a detailed geophysical exploration of the site to confirm the availability and saturations of preexisting fluid(hydrocarbon and water)are encouraged

关键词： Rio Bonito Effective permeability fluid transmissibility CO_(2)storage prospect Reservoir quality Overburden integrity flow zones

feeding ecology and interactions with mammal hosts in a symbiotic genus of birds(Buphagus spp.)in Namibia

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Avian Research 2024年第3期15卷 336-344页

作者： Michael s.Lukubwe Daniel Velarde-Garcéz fernando sequeira susana Lopes Adrian J.f.K.Craig Vanessa A.Mata Department of Zoology and Entomology Rhodes UniversityMakhandaSouth Africa Department of Wildlife Management and Tourism studies University of NamibiaKatima Mulilo CampusNamibia Departamento de Biologia Faculdade de CiênciasUniversidade do PortoPortoPortugal CIBIO Centro de Investigação em Biodiversidade e Recursos GenéticosInBIO Laboratório AssociadoCampus de VairãoVairãoPortugal BIOPOLIs Program in Genomics Biodiversity and Land PlanningCIBIOCampus de VairãoVairãoPortugal

As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic *** to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the type of symbiotic relationship can be *** addition to providing a cleaning service to the host by removing ticks,oxpeckers frequently feed on blood,mucus,and saliva,inflicting potential damage on the ***,we used DNA metabarcoding on faecal samples to analyze the taxonomic composition of the trophic interactions of the Yellow-billed Oxpecker(Buphagus africanus)and Red-billed Oxpecker(***)in northeastern *** contrast to conventional methods,DNA metabarcoding allows for a detailed identification of dietary resources encompassing both mammal hosts and consumed arthropods within the same *** this information,we examined differences in the diet composition between oxpecker species and localities,as well as the co-occurrence between host and arthropod *** findings revealed that oxpeckers predominantly source their diet from mammals,ticks,and flies;however,ticks and flies rarely co-occur in the diet of an *** observed variability among individuals in their feeding ecology,which is strongly correlated with locality and,to a lesser extent,with the mammal *** noted a high degree of mobility between hosts within relatively short periods,with 32%of the samples showing traces of at least two mammal *** study illustrates the dynamic foraging behavior of these specialized symbiotic birds,shedding light on their potential role in pest control services and disease transmission.

关键词： Commensalism Diet DNA metabarcoding Oxpeckers Parasitism Trophic ecology

The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 711-724页

作者： f.JAZINI DORCHEH M.GHAssEMI fuel Cells and Nano systems(fCNs)Laboratory Department of Mechanical EngineeringK.N.Toosi University of TechnologyTehran 19697Iran

In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological *** numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the *** this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation *** the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load *** particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous *** is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation.

关键词： surface acoustic wave microfluidics numerical simulation particle tracing acoustic streaming

Antimicrobial,antibiofilm,angiogenesis,anti-inflammatory,and wound healing activities of zinc nanoparticles green synthesized using ferula macrecolea extract

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Asian Pacific Journal of Tropical Biomedicine 2024年第6期14卷 259-268页

作者： sultan f.Alnomasy Department of Medical Laboratories sciences College of Applied Medical SciencesShaqra UniversityAl-Quwayiyah 19257Saudi Arabia

Objective:To assess the antimicrobial,antibiofilm,anti-inflammatory,angiogenic,and wound healing activities of zinc nanoparticles(ZNPs)green synthesized using ferula macrecolea ***:The green synthesis was conducted using the precipitation ***,the minimum inhibitory concentration(MIC),minimum bactericidal concentration(MBC),and minimum biofilm inhibition concentration 50%(MBIC50)of ZNPs against staphylococcus aureus(***)and Pseudomonas aeruginosa(***)were *** effects of ZNPs on the gene expressions of staphylococcus spp.[intracellular adhesion A(icaA)and D(icaD)]and ***(rhlI and rhlR)were investigated using quantitative real-time *** addition,the effects of ZNPs on wound healing,angiogenesis,and anti-inflammatory markers were ***:The green-synthesized ZNPs demonstrated significant antimicrobial efficacy against *** and *** biofilm formation in *** and *** was also inhibited by ZNPs with MBIC50 values of 3.30μg/mL and 2.08μg/mL,***,ZNPs downregulated the expression of biofilm-related genes icaA,icaD,rhlI,and rhlR in the tested *** also demonstrated promising in vitro wound healing effects by promoting fibroblast cell proliferation and wound closure in a dose-dependent manner.A significant increase in the expression of HLA-G5 and VEGf-A genes as well as a marked decrease in the expression of Nf-κB,IL-1β,and TNf-αgenes were observed in cells treated with ZNPs compared to the control group(Psions:ZNPs display promising antibacterial effects against *** and *** and wound-healing effects by inhibiting biofilm formation,inducing angiogenesis,and reducing ***,further studies must be conducted to specify the accurate mechanisms of action and toxicity of ZNPs.

关键词： Wound healing Antibacterial Angiogenesis Nanomedicine ferula macrecolea Inflammation

Langmuir-schaefer film Investigation and Density functional Theory Band Gap Calculations of Calix[n]arene-Para-Aminobenzoic Acid for Drug Nanosensor Application

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Journal of Wuhan University of Technology(Materials science) 2024年第5期39卷 1311-1318页

作者： WONG Yeong Yi f L supian A Radzwan M Musa N f N Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DfT).Using the Langmuir-schaefer(Ls)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:*** of the Ls films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),fourier-transform infrared spectroscopy(fTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNs).The band gap reduction obtained in the DfT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory Langmuir-schaefer PABA sensor