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Atmospheric chemistry of trifluorodicarbonyls initiated by Cl atoms:Reactivity trends,mechanism,and acid formation yields

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Journal of Environmental Sciences 2025年第5期151卷 12-25页

作者： pedro l.lugo Vianni g.Straccia Cynthia B.Rivela Mariano A.Teruel María B.Blanco laboratorio Universitario de Química y Contaminación del Aire(l.U.Q.C.A) Instituto de Investigaciones en Fisicoquímica de Córdoba(I.N.F.I.Q.C.)Dpto.de Fisicoquímica.Facultad de Ciencias QuímicasUniversidad Nacional de Córdoba.Ciudad Universitaria5000 CórdobaArgentina Institute for Atmospheric and Environmental Research University of WuppertalDE-42097 WuppertalGermany

Rate coefficients of the gas-phase reactions of Cl atoms with a series of fluorinated diketones(FDKs):CF_(3)C(O)CH_(2)C(O)CH_(3)(TFP),CF_(3)C(O)CH_(2)C(O)CH_(2)CH_(3)(TFH)and CF_(3)C(O)CH_(2)C(O)CH(CH_(3))2(TFMH),have been measured at(298±2)K and under atmospheric *** experiments were performed using the relative-rate method with a gC-FID detection *** different determinations and references used,the following rate coefficients were obtained(in cm3/(molecule·sec)):k_(4)(TFP+Cl)=(1.75±0.21)×10^(−10),k_(5)(TFH+Cl)=(2.05±0.23)×10^(−10),k_(6)(TFMH+Cl)=(2.71±0.34)×10^(−10).Reactivity trends of FDKs were discussed and Free Energy Relationships analysis was *** expression lgkOH=1.68 lgkCl+5.71 was obtained for the reactivity of the studied FDKs together with similar unsaturated VOCs with Cl and OH radicals Additionally,acetic acid(CH_(3)C(O)OH)and trifluoroacetic acid(CF_(3)C(O)OH)were positively identified and quantified as degradation products using in situ FTIR *** to the identified products,atmospheric chemical mechanisms were *** atmospheric implications of the studied reactions were assessed by the estimation of the tropospheric lifetimes of TFP,TFH,and TFMH concerning their reaction with Cl atoms to be 48,41,and 31 hours,*** relatively short residence in the atmosphere of the fluorocarbons studied will have a local/regional impact with restricted *** warming potential(gWP(20 yr))calculated for the studied fluoro diketones were 0.014,0.003 and 0.001 for TFP,TFH and TFMH,respectively with a negligible contribution to the greenhouse effect.

关键词： Fluorinated diketones Kinetics SPME-gC-FID FTIR in situ SAR Free energy relationships

Modeling net-charge fluctuations in heavy-ion collisions at the lHC

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Chinese Physics C 2025年第1期49卷 281-289页

作者： g.O.Ambaryan A.S.Chernyshov g.Kh.Eyyubova V.l.Korotkikh I.P.lokhtin S.V.petrushanko A.M.Snigirev E.E.Zabrodin Physics Department Lomonosov Moscow State UniversityRU-119991 MoscowRussia Skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State UniversityRU-119991 MoscowRussia Bogoliubov laboratory of Theoretical Physics Joint Institute for Nuclear ResearchRU-141980 DubnaRussia Department of Physics University of OsloN-0316 OsloNorway

Analysis of Pb+Pb data for net-charge fluctuations at lHC energies using the HYDJET++model is *** strongly intensive quantities D and Σ were used to remove the effects related to system volume *** employed two versions of HYDJET++for the *** first one is the standard or default version,whereas the second one is a modification that takes into account explicit event-by-event conservation of the electric net-charge of produced *** inclusion of the canonical net-charge conservation in the model allows for better description of the experimental data obtained by the AlICE and CMS Collaborations.A comparison with calculations from other models is also presented.

关键词： relativistic heavy-ion collisions net-charge fluctuations strongly intensive variables canonical charge conservation

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina Hromada Patrick Heimel Markus Kerbl lászlógál Sylvia Nürnberger Barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes C.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller David Hercher Department life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNgCs). However, the use of tNgCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNgC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNgCs and compared the various features of these improved silk^(+) tNgCs with the tubes without holes(silk^(–) tNgCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNgCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNgCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNgCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNgCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Seasonal influence on miRNA expression dynamics of extracellular vesicles in equine follicular fluid

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Journal of Animal Science and Biotechnology 2025年第1期16卷 136-152页

作者： Jean M.Feugang Ahmed gad Nico g.Menjivar ghassan M.Ishak Samuel gebremedhn Melba O.gastal Notsile H.Dlamini Radek Prochazka Eduardo l.gastal Dawit Tesfaye Department of Animal and Dairy Sciences Mississippi State UniversityMississippi StateMS 39762USA Animal Reproduction and Biotechnology laboratory(ARBl) Department of Biomedical SciencesCollege of Veterinary Medicine and Biomedical SciencesColorado State UniversityFort CollinsCO 80523USA Department of Animal Production Faculty of AgricultureCairo UniversityGiza 12613Egypt Department of Surgery and Obstetrics College of Veterinary MedicineUniversity of BaghdadBaghdad 10011Iraq Animal Science School of Agricultural SciencesSouthern Illinois UniversityCarbondaleIL 62901USA J.R.Simplot Company KunaID 83634USA Institute of Animal Physiology and genetics Czech Academy of SciencesLiběchov 27721Czech Republic

Background Ovarian follicular fluid(FF)is a dynamic environment that changes with the seasons,affecting follicle development,ovulation,and oocyte *** in the follicles release tiny particles called extracellular vesicles(EVs)containing vital regulatory molecules,such as microRNAs(miRNAs).These miRNAs are pivotal in facilitating commu-nication within the follicles through diverse signaling and information transfer ***-coupled miRNA signaling is implicated to be associated with ovarian function,follicle and oocyte growth and response to various environmen-tal ***,we investigated how seasonal variations directly influence the ovulatory and anovulatory states of ovarian follicles and how are they associated with follicular fluid EV-coupled miRNA dynamics in *** Ultrasonographic monitoring and follicular fluid aspiration of preovulatory follicles in horses during the ano-vulatory(spring:non-breeding)and ovulatory(spring,summer,and fall:breeding)seasons and subsequent EV isola-tion and miRNA profiling identified significant variation in EV-miRNA cargo *** identified 97 miRNAs with dif-ferential expression among the groups and specific clusters of miRNAs involved in the spring transition(miR-149,-200b,-206,-221,-328,and-615)and peak breeding period(including miR-143,-192,-451,-302b,-100,and let-7c).Bioinformatic analyses showed enrichments in various biological functions,e.g.,transcription factor activity,transcrip-tion and transcription regulation,nucleic acid binding,sequence-specific DNA binding,p53 signaling,and post-trans-lational *** analyses revealed distinct sets of significantly up-and down-regulated miRNAs associ-ated with spring anovulatory(Cluster 1)and summer ovulation–the peak breeding season(Clusters 4 and 6).Conclusions The findings from the current study shed light on the dynamics of FF-EV-coupled miRNAs in relation to equine ovulatory and anovulatory seasons,and their roles in understanding the

关键词： Extracellular vesicle Follicle growth Follicular fluid Horse Mare Ovulation Pre-ovulation Seasonal breeding

Pro-resolving lipid mediator reduces amyloid-β42–induced gene expression in human monocyte–derived microglia

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Neural Regeneration Research 2025年第3期20卷 873-886页

作者： Ying Wang Xiang Zhang Henrik Biverstål Nicolas gBazan Shuai Tan Nailin li Makiko Ohshima Marianne Schultzberg Xiaofei li Department of Neurobiology Care Sciences&SocietyDivision of NeurogeriatricsKarolinska InstitutetStockholmSweden Department of Neurology Neuroscience CenterThe First Hospital of Jilin UniversityChangchunJilin ProvinceChina Department of Physiology and Pharmacology Karolinska InstitutetStockholmSweden Department of Biosciences and Nutrition Karolinska InstitutetHuddingeSweden Neuroscience Center of Excellence Louisiana State UniversityNew OrleansLAUSA Department of Medicine SolnaClinical Pharmacology GroupKarolinska University HospitalStockholmSweden

Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment of Alzheimer's disease to prevent/stop inflammation and combat disease pathology. Therefore, it is important to clarify whether they counteract the expression of genes and proteins induced by amyloid-β. With this objective, we analyzed the relevance of human monocyte–derived microglia for in vitro modeling of neuroinflammation and its resolution in the context of Alzheimer's disease and investigated the pro-resolving bioactivity of maresin 1 on amyloid-β42–induced Alzheimer's disease–like inflammation. Analysis of RNA-sequencing data and secreted proteins in supernatants from the monocyte-derived microglia showed that the monocyte-derived microglia resembled Alzheimer's disease–like neuroinflammation in human brain microglia after incubation with amyloid-β42. Maresin 1 restored homeostasis by down-regulating inflammatory pathway related gene expression induced by amyloid-β42 in monocyte-derived microglia, protection of maresin 1 against the effects of amyloid-β42 is mediated by a re-balancing of inflammatory transcriptional networks in which modulation of gene transcription in the nuclear factor-kappa B pathway plays a major part. We pinpointed molecular targets that are associated with both neuroinflammation in Alzheimer's disease and therapeutic targets by maresin 1. In conclusion, monocyte-derived microglia represent a relevant in vitro microglial model for studies on Alzheimer's disease-like inflammation and drug response for individual patients. Maresin 1 ameliorates amyloid-β42–induced changes in several genes of importance in Alzheimer's disease, highlighting its potential as a therapeutic target for Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β maresin microglia monocyte neuroinflammation resolution RNA-sequencing specialized pro-resolving lipid mediator

Non-existence of Shimura curves of Mumford type generically in the non-hyperelliptic locus

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Science China Mathematics 2025年

作者： Xin lü Shengli Tan Kang Zuo School of Mathematical Sciences Key Laboratory of Mathematics and Engineering Applications(Ministry of Education) Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal University School of Mathematics and Statistics Wuhan University Institut für Mathematik Universit?t Mainz

We show that there does not exist any Shimura curve with a strictly maximal Higgs field generically in the Torelli locus of non-hyperelliptic curves of genus g≥4. In particular, Shimura curves of Mumford type are not...

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lessons learned from requirements gathering for virtual reality simulators

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Virtual Reality & Intelligent Hardware 2021年第5期3卷 407-422页

作者： Vivian gÓMEZ Kelly peÑARANDA Pablo FIgUEROA Department of Systems and Computing Engineering Universidad de Los AndesBogotá7620001Colombia

Background This paper shows how current collaborative virtual environments(VEs)such as Mozilla Hubs and AltspaceVR can aid in the task of requirements gathering in VR for simulation and *** We performed a qualitative study on our use of these technologies in the requirements gathering of two *** Our results show that requirements gathering in virtual reality has an impact on the process of requirements *** report advantages and shortcomings that will be of interest to future *** example,we found that VR sessions for requirements gathering in current VEs could benefit from better pointers and better sound *** Current VEs are useful for the requirements gathering task in the development of VR simulators and VR training environments.

关键词： Human computer interaction Virtual environment Requirements gathering globally dispersed teams VR simulators and training

The effect of adsorbent textural and functional properties on model naphthenic acid adsorption

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Journal of Environmental Sciences 2025年第2期148卷 27-37页

作者： Tyler M.Roy Elmira Nazari Oliver K.l.Strong Paul R.pede Andrew J.Vreugdenhil Material Science Department of ChemistryTrent University1600 West BankPeterboroughOntario K9L 0G2Canada Carbonix 690 Mountain RdSuite 200Fort William First NationOntario P7J 1G8Canada

Naphthenic acids,NAs,are a major contaminant of concern and a focus of much research around remediation of oil sand process affected waters,*** activated carbon adsorbents are an attractive option given their low cost of fabrication and implementation.A deeper evaluation of the effect NA structural differences have on uptake affinity is *** we provide an in-depth exploration of NA adsorption including many more model NA species than have been assessed previously with evaluation of adsorption kinetics and isotherms at the relevant alkaline pH of OSPW using several different carbon adsorbents with pH buffering to simulate the behaviour of real *** for the NA varied considerably regardless of the activated carbon used,ranging from 350 mg/g to near zero highlighting recalcitrant *** equilibrium data was explored to identify structural features of these species and key physiochemical properties that influence *** found that certainNAwill be resistant to adsorptionwhen hydrophobic adsorbents are *** isotherm modelling helped explore interactions occurring at the interface between NA and adsorbent *** identified the importance of NA hydrophobicity for activated carbon *** is also presented that indicates favorable hydrogen bonding between certain NA and surface site hydroxyl groups,demonstrating the importance of adsorbent surface functionality for NA *** research highlights the challenges associated with removing NAs from OSPW through adsorption and also identifies howadsorbent surface chemistry modification can be used to increase the removal efficiency of recalcitrant NA species.

关键词： Adsorption Activated carbon Model naphthenic acids Isotherm modelling

Modeling slow deformation of polygonal particles using DEM

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Particuology 2008年第6期6卷 506-514页

作者： Andrés A. pea pedro g. lind Hans J. Herrmann Institute for Computational Physics Universitt Stuttgart Computational Physics IfB HIF E12 ETH Hnggerberg CH-8093 Zrich Switzerland Departamento de Física Universidade Federal do Ceará

We introduce two improvements in the numerical scheme to simulate collision and slow shearing of irregular particles. First, we propose an alternative approach based on simple relations to compute the frictional contact forces. The approach improves efficiency and accuracy of the Discrete Element Method （DEM） when modeling the dynamics of the granular packing. We determine the proper upper limit for the integration step in the standard numerical scheme using a wide range of material parameters. To this end, we study the kinetic energy decay in a stress controlled test between two particles. Second, we show that the usual way of defining the contact plane between two polygonal particles is, in general, not unique which leads to discontinuities in the direction of the contact plane while particles move. To solve this drawback, we introduce an accurate definition for the contact plane based on the shape of the overlap area between touching particles, which evolves continuously in time.

关键词： granular media Discrete element method Slow deformation Contact forces