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A simulation study on spatial and time resolution for a cost-effective positron emission particle tracking system

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Particuology 2024年第5期88卷 312-322页

作者： Josephine Oppotsch Matthias Steinke Miriam Fritsch Fritz-Herbert Heinsius thomas Held nikoline Hilse Viktor Scherer Ulrich Wiedner Ruhr-Universität Bochum Institut für Experimentalphysik I44801 BochumGermany Ruhr-Universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

this work is the second part of a simulation study investigating the processing of densely packed and moving granular assemblies by positron emission particle tracking (PEPt).Since medical positron emission tomography (PEt) scanners commonly used for PEPt are very expensive,a PEt-like detector system based on cost-effective organic plastic scintillator bars is being developed and tested for its *** this context,the spatial resolution of a resting positron source,a source moving on a freely designed model path,and a particle motion given by a discrete element method (DEM) simulation is studied using Monte Carlo simulations and the software toolkit *** not only extended the simulation and reconstruction to a moving source but also significantly improved the spatial resolution compared to previous work by adding oversampling and iteration to the reconstruction ***,in the case of a source following a trajectory developed from DEM simulations,a very good resolution of about 1 mm in all three directions and an average 3D deviation between simulated and reconstructed events of 2.3 mm could be ***,the resolution for realistic particle motion within the generic grate system (which is the test rig for further experimental studies) is well below the smallest particle *** simulation of the dependence of the reconstruction accuracy on tracer particle location revealed a nearly constant efficiency within the entire detector system,which demonstrates that boundary effects can be neglected.

关键词： Positron emission particle tracking Monte Carlo method time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)

A simulation study for a cost-effective PEt-like detector system intended to track particles in granular assemblies

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Particuology 2024年第1期84卷 117-125页

作者： Josephine Oppotsch Antonios Athanassiadis Miriam Fritsch Fritz-Herbert Heinsius thomas Held nikoline Hilse Viktor Scherer Matthias Steinke Ulrich Wiedner Ruhr-Universität Bochum Institut für Experimentalphysik I44801 BochumGermany Ruhr-Universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

Since many industrial applications rely on the processing of densely packed and moving granular ma-terial,obtaining bulk internal information on the particle movement inside the reactors is of great *** information can be delivered by Positron Emission Particle tracking(PEPt).By marking pellets with a positron-emitting radioisotope,the position of these tracer particles can be determined via the time-of-flight differences of the emitted gamma-ray *** current paper proposes a PEt-like detector system based on cost-effective organic plastic scintillators instead of the more common but expensive inorganic *** system is currently under construction and was tested for its resolution and efficiency in this simulation *** Monte Carlo simulations and the software toolkit Geant4,three different geometries(an empty glass box,a generic grate system,and a cubic box of 1 m3 completely filled with pellets)were investigated,leading to a spatial resolution in the millimeter range and an efficiency,defined as the ratio of reconstructed decay locations to simulated decays,of 2.7%,1.4%,and 0.3%.

关键词： Positron emission particle tracking Geant4 Monte Carlo method time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)

Geomorphological responses of rivers to active tectonics along the Karahay?t Fault, Western türkiye

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Journal of Mountain Science 2024年第5期21卷 1464-1474页

作者： Savaş tOPAL Pamukkale University Department of Geological EngineeringKınıklıCampusDenizli 20160Türkiye

Understanding the topography in active tectonic areas and assessing the rates and models of active deformation in the upper crust are primary objectives in tectonic geomorphology studies. the drainage pattern of river systems is highly sensitive to tectonically induced changes, and it often preserves the records of the formation and progression of most tectono-geomorphic processes within its boundaries. therefore, the evolution of landforms is a consequence of the evolution of individual drainage basins in which they are formed. Assessing the rates of tectonic deformation using geomorphic data is a traditionally adopted method to characterize the nature of active faults. Globally, the Digital Elevation Model(DEM) is widely used as a crucial tool to analyze the morphotectonic features of drainage basins. in this study, some geomorphic indices were applied to investigate the impact of tectonism on landscape along the Karahay?t Fault and its associated drainage areas. these geomorphic indices are mountain front sinuosity(Smf values between 1.17-1.52), valley floor width-to-height ratio(Vf values between 0.25-1.46), basin asymmetry factor(AF values between 15-72), drainage basin shape(Bs values between 3.18-6.01), hypsometric integral and curve(Hi values between 0.32-047), channel sinuosity(S values between 1-1.6), normalized steepness index(Ksn values between 1-390) and Chi integral(χ values between 200-4400). the development of drainage areas on the hanging wall and footwall block of the Karahayit Fault differs depending on the uplift. the drainage areas developed on the hanging wall present different patterns depending on the regional uplift caused by the fault. this reveals that the fault contributed significantly to the development of drainage areas and regional uplift in the region. in addition, the maximum earthquake magnitude that may occur in the future on the Karahayit Fault, whose activity is supported by geomorphic indices, is calculated as 6.23. Since an ea

关键词： Drainage basins Geomorphic indices normalized steepness index(Ksn) Chi integral(χ) Morphotectonic features Karahayıt Fault

Commentary on"Speed and surface steepness affect internal tibial loading during running"

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Journal of Sport and Health Science 2024年第1期13卷 125-126页

作者： Michael Baggaley Arash Khassetarash Faculty of Kinesiology University of CalgaryCalgaryAB T2N 1N4Canada McCaig institute for Bone and Joint Health University of CalgaryCalgaryAB T2N 4Z6Canada

it is a pleasure to write a commentary on the work of *** Rice and colleagues,l who have advanced our understanding of how the mechanical loading environment of the tibia changes as a function of running grade and *** is important that we understand how the tibia is loaded during conditions that an individual is likely to encounter when running as it is these internal loads which we believe are responsible for the development of bone-stress injuries.

关键词： loading injuries likely

the Paris 2024 Olympic and Paralympic Games

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Journal of Sport and Health Science 2024年第6期13卷 717-718页

作者： Walter Herzog Human Performance Laboratory Faculty of KinesiologyUniversity of CalgaryCalgaryAB T2N 1N4Canada

the first modern Olympic Games took place in Athens in *** in those early days of the Olympics only amateur and gentleman athletes were allowed to participate,today Olympic athletes are highly trained professionals often dedicating decades of preparation for the chance to compete in the Olympic *** sharp contrast to these highly trained athletes,the world’s population becomes less physically active on average,resulting in an obesity epidemic with associated metabolic syndrome and increased mortality through non-communicable diseases(e.g.,Collins et al.^(1)).

关键词： Olympic allowed sharp

Long-term monitoring reveals the effect of precipitation and silviculture on nothofagus regeneration in northern Patagonia mixed forests

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Ecological Processes 2024年第02期13卷 103-117页

作者： Georgina Sola Camila Mateo Alejandro Dezzotti Paula Marchelli Hernán Attis Beltrán Renato Sbrancia Luis Chauchard Marcelo González Pe?alba Martín Lara Verónica El Mujtar Consejo nacional de investigaciones Científicas y técnicas (COniCEt ) Asentamiento Universitario San Martín de los Andes (AUSMA-UnCo) instituto de investigaciones Forestales y Agropecuarias Bariloche (iFAB) Instituto Nacional de Tecnología Agropecuaria (INTA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Departamento de Conservación y Manejo Parque Nacional Lanín- Administración de Parques Nacionales (PNL-APN)

Background tree regeneration is a key component of resilience because it promotes post-disturbance recovery of forests. northwestern Patagonia from Argentina is occupied by nothofagus alpina（na）, n. obliqua（no）, and n. dombeyi（nd） forests that grow along an.i.t.nse precipitation gradient, managed throughout shelterwood silvicultural system by technicians of the Lanin natural Reserve. the objective of this study was to evaluate the influence of seeding cuttings over the dynamics of nothofagus mixed forests across landscape（precipitation gradient） based mainly on the composition and abundance of tree regeneration, permanent sampling plots and generalized linear mixed models. in particular, we analysed:（i） the structure of sexual and asexual regeneration during nd > 20 years after harvest（the dynamics of managed forests）, and（ii） the structure of sexual regeneration in primary and managed forests after > 20 years of harvest（the effect of silviculture）.Results nd was the most abundant species in the regeneration of managed forests during all periods in both sites despite its lower contribution to the adult cohort. During the 10–20 years period after harvest, the humid site exhibited higher regeneration density than the mesic site(120,000 and 6000 ind ha-1, respectively), and it decreased afterwards. the number of established regeneration（> 2 m height） was lower for na in the mesic site and for no in the humid site(0 and 57 ind ha-1, respectively). However, in comparison to no, na showed a higher number of sprouted stumps and sprouts per stump, and a higher sprout height in the mesic site. no exhibited higher sprout mortality in the humid site. Finally, the regeneration of primary forests showed lower density and height, and a more balanced composition than that of managed *** the silvicultural effects on the mixed forest regeneration dynamics was strongly influenced by the condition of sites. therefore, management prescriptions should be adj

关键词： nothofagus alpina nothofagus obliqua nothofagus dombeyi Basal sprouting Shelterwood silvicultural system Ecological resilience

Valuable Beyond Vulnerable: A Scoping Review on the Contributions of Older Forced Migrants in Post-migration Recovery

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international Journal of Disaster Risk Science 2024年第2期15卷 186-197页

作者： Prince Chiagozie Ekoh Christine A.Walsh Faculty of Social Work University of CalgaryCalgaryAB T2N 1N4Canada Department of Social Work University of NigeriaNsukka 410001Nigeria

During times of crisis, including pandemics, climate change, and forced migration, much of the discourse in ageing research and intervention centers on the vulnerabilities of older adults. Unfortunately, the valuable contributions of older adults to post-disaster recovery and healing are often overlooked and undervalued. Our aim in this scoping review is to shed light on the critical contributions of older forced migrants to post-migration recovery. We set the scene by introducing the two significant global demographic changes of the twenty-first century: forced migration and ageing. We provide a discourse on older forced migrants, ageing in situations of forced migration, and some of the challenges faced by older forced migrants. We then present some of the substantial roles of older forced migrants in post-migration recovery, including building resilience, contributing to culture and language transfer, providing emotional support, offering mentorship and leadership, participating in community building, and fostering social integration. We close by highlighting some of the lessons that can be drawn from understanding the unique roles played by older adults in post-forced migration recovery and the key actions necessary to promote these roles.

关键词： Older displaced persons Older forced migrants Older refugees Post-forced migration recovery

B-cell and antibody responses to SARS-CoV-2:infection,vaccination,and hybrid immunity

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Cellular & Molecular immunology 2024年第2期21卷 144-158页

作者： Dennis Lapuente thomas H.Winkler Matthias tenbusch institut für klinische und molekulare Virologie Universitätsklinikum Erlangen und Friedrich-Alexander-Universität(FAU)Erlangen-NürnbergSchlossgarten 491054 ErlangenGermany Department of Biology Division of GeneticsNikolaus-Fiebiger-Center for Molecular MedicineFriedrich-Alexander-Universität Erlangen-Nürnberg(FAU)ErlangenGermany Medical immunology Campus Erlangen Friedrich-Alexander-Universität(FAU)Erlangen-NürnbergSchlossplatz 191054 ErlangenGermany

the emergence of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)in 2019 prompted scientific,medical,and biotech communities to investigate infection-and vaccine-induced immune responses in the context of this pathogen.B-cell and antibody responses are at the center of these investigations,as neutralizing antibodies(nAbs)are an important correlate of protection(COP)from infection and the primary target of SARS-CoV-2 vaccine *** addition to absolute levels,nAb longevity,neutralization breadth,immunoglobulin isotype and subtype composition,and presence at mucosal sites have become important topics for scien.i.t. and health policy *** recent pandemic was and still is a unique setting in which to study de novo and memory B-cell(MBC)and antibody responses in the dynamic interplay of infection-and vaccine-induced *** also provided an opportunity to explore new vaccine platforms,such as mRnA or adenoviral vector vaccines,in unprecedented cohort *** with the technological advances of recent years,this situation has provided detailed mechanistic insights into the development of B-cell and antibody responses but also revealed some unexpected *** this review,we summarize the key findings of the last 2.5 years regarding infection-and vaccine-induced B-cell immunity,which we believe are of significant value not only in the context of SARS-CoV-2 but also for future vaccination approaches in endemic and pandemic settings.

关键词： SARS-CoV-2 neutralizing antibodies memory responses vaccines igG4

Epitranscriptomic Regulation of nMDA Receptors Rears its Ugly Head in Chemotherapy-induced neuropathic Pain

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neuroscience Bulletin 2024年第8期40卷 1209-1211页

作者： Wing Lam Yu Gerald W.Zamponi Department of Clinical neurosciences Hotchkiss Brain InstituteAlberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryAB T2N 4N1Canada

number of different cancer chemotherapy agents such as cisplatin,oxaliplatin,and paclitaxel can lead to nerve damage,thereby giving rise to neuropathic pain states that present with mechanical and cold allodynia[1].Although these pain conditions often resolve after completion of the chemotherapy,a significant portion of patients exhibit longlasting pain that can persist longer than 12 months with a negative impact on the quality of life of affected individuals[1].

关键词： chemotherapy pain damage