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Experimental investigation on slip conditions during thread rolling with flat dies

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Friction 2024年第1期12卷 136-143页

作者： Stefan VOLZ peter GROCHE Institute for Production Engineering and Forming Machines Technical University DarmstadtOtto-Berndt Straße 2Darmstadt 64287Germany

The process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process *** this work,an effort is made to closely investigate and understand the process limits caused by excessive slippage of the *** measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process *** differences in slippage were observed,depending on the tribological *** systems with polymer based lubricants showed excessive slippage at low stroke rates,systems using oil or no lubricant endured higher stroke rates before process limits were *** optical measurements revealed three major forms of slippage:successful rolling without slippage,failure due to excessive slippage at process start,and failure due to excessive slippage at around one workpiece rotation.

关键词： rolling incremental forming thread rolling slippage profile rolling

Skeletal muscle as a molecular and cellular biomarker of disease progression in amyotrophic lateral sclerosis:a narrative review

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Neural Regeneration Research 2024年第4期19卷 747-753页

作者： peter H.King Department of Neurology and Center for Neurodegeneration and Experimental Therapeutics The University of Alabama at BirminghamBirminghamALUSA Birmingham Veterans Affairs Medical Center BirminghamALUSA

Amyotrophic lateral sclerosis is a fatal multisystemic neurodegenerative disease with motor neurons being a primary *** progressive weakness is a hallmark feature of amyotrophic lateral sclerosis,there is considerable heterogeneity,including clinical presentation,progression,and the underlying triggers for disease *** on longitudinal studies with families harboring amyotrophic lateral sclerosis-associated gene mutations,it has become apparent that overt disease is preceded by a prodromal phase,possibly in years,where compensatory mechanisms delay symptom *** 85-90%of amyotrophic lateral sclerosis is sporadic,there is a strong need for identifying biomarkers that can detect this prodromal phase as motor neurons have limited capacity for *** Food and Drug Administration-approved therapies work by slowing the degenerative process and are most effective early in the *** muscle,including the neuromuscular junction,manifests abnormalities at the earliest stages of the disease,before motor neuron loss,making it a promising source for identifying biomarkers of the prodromal *** accessibility of muscle through biopsy provides a lens into the distal motor system at earlier stages and in real *** advent of“omics”technology has led to the identification of numerous dysregulated molecules in amyotrophic lateral sclerosis muscle,ranging from coding and non-coding RNAs to proteins and *** technology has opened the door for identifying biomarkers of disease activity and providing insight into disease mechanisms.A major challenge is correlating the myriad of dysregulated molecules with clinical or histological progression and understanding their relevance to presymptomatic phases of *** are two major goals of this *** first is to summarize some of the biomarkers identified in human amyotrophic lateral sclerosis muscle that have a clinicopathological correlation with disease activi

关键词： amyotrophic lateral sclerosis biomarkers clinicopathological correlation disease progression muscle biomarkers neurogenic atrophy neuromuscular junction non-coding RNAs presymptomatic stages skeletal muscle SOD1G93A mouse model

A product version of the Hilton-Milner-Frankl theorem

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Science China Mathematics 2024年第2期67卷 455-474页

作者： peter Frankl Jian Wang Alfréd Rényi Institute of Mathematics Hungarian Academy of SciencesBudapest H-1053Hungary Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| < t, | ∩ {G : G ∈ G}| < t. In the present paper,we determine the maximum product of the sizes of two non-trivial cross t-intersecting families of k-subsets of{1, 2,..., n} for n≥4(t + 2)2k2, k≥5, which is a product version of the Hilton-Milner-Frankl theorem.

关键词： extremal set theory cross t-intersecting family product version non-trivial

A Population Dynamics Approach to the Distribution of Space Debris in Low Earth Orbit

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Communications on Applied Mathematics and Computation 2024年第1期6卷 340-353页

作者： John Jurkiewicz peter Hinow Department of Mathematical Sciences University of Wisconsin-MilwaukeeMilwaukeeWI53201USA

The presence of the debris in the Earth’s orbit poses a significant risk to human activity in outer *** debris population continues to grow due to ground launches,the loss of external parts from space ships,and uncontrollable collisions between objects.A computationally feasible continuum model for the growth of the debris population and its spatial distribution is therefore *** we propose a diffusion-collision model for the evolution of the debris density in the low-Earth orbit and its dependence on the ground-launch *** parametrize this model and test it against data from publicly available object catalogs to examine timescales for the uncontrolled ***,we consider sensible launch policies and cleanup strategies and how they reduce the future risk of collisions with active satellites or space ships.

关键词： Population dynamics Space debris Kessler syndrome Diffusion Low-Earth orbit

Diagnostic tools for fecal incontinence: Scoring systems are the crucial first step

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World Journal of Gastroenterology 2024年第6期30卷 516-522页

作者： peter Liptak Martin Duricek peter Banovcin Clinic of Internal Medicine-Gastroenterology University Hospital in MartinJessenius Faculty of Medicine in MartinComenius UniversityMartin 03601Slovakia

The main aim of this editorial is to comment on the recent article published by Garg et al in the World Journal of Gastroenterology 2023;29:*** original research presents a new scoring system for fecal *** incontinence is a chronic disease with a severe impact on the quality of life of the *** social stigmatization often leads to significant underreporting of the condition even during visits to a specialist and could lead to further misman-agement or non-existent management of the *** important fact is that patients are often unable to describe their condition when not asked precisely defined *** problem is partially resolved by scoring *** scoring systems are commonly used;however,each of them has their *** example,the absence of different kinds of leakage besides flatus and stool could further lead to underscoring the incontinence ***,there has long been a call for a more precise scoring *** correct identification of the presence and severity of fecal incontinence is paramount for further diagnostic approach and for choosing the appropriate therapy *** editorial describes fecal incontinence,its effect on quality of life in general and further evaluates the diagnostic approach with a particular focus on symptom scoring systems and their implications for clinical practice.

关键词： Incontinence Fecal Scoring system Questionary Quality of life

Optimization of product characteristics of porous carbon agglomerates using a design of experiments in fluidized bed agglomeration

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Particuology 2024年第6期89卷 258-269页

作者： Martin Oelofse Robert Rack Marcelle Hilden peter Langguth Department of Pharmaceutical Technology and Biopharmaceutics Johannes Gutenberg UniversityMainzGermany Carbon Advanced Solutions GmbH HeuchelheimGermany

Spraying parameters during particle agglomeration processes can affect the agglomeration kinetics and particle *** study was conducted to better understand the influence of the spraying parameters in a fluidized bed wet agglomeration process,and the influence on the stability characteristics of carbon tablets.A formulation based on fine carbon and peroxide powder,as well as carboxymethyl cellulose as a binder,was used to produce agglomerates in a first production *** in a second production step carbon tablets with a high porosity were molded for the customer goods *** optimization of the compressive strength of these carbon tablets was the goal of the *** agglomerates were produced with a laboratory scale granulator called“ProCell”and were compressed with a five-cavity mechanical *** screening of the agglomeration process parameters and their influence on the agglomerates quality,as well as the performance characteristics of the carbon tablets,were investigated using a multilevel factorial *** experimental runs were done by varying atomized air pressure and feed rate of the *** was determined by the design *** findings of the statistical trials showed that low atomized air pressure and a low feed rate lead to a higher tablet compressive strength.

关键词： Wet agglomeration Fluidized bed Design of experiments Carbon agglomerates and tablets

Chinese Medicine,Acupuncture and Science

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Chinese Medicine and Culture 2024年第1期7卷 77-85页

作者： peter Eckman Private practitioner San Francisco 94131USA

Ever since the introduction of Western biomedicine into China, there has been friction between proponents of this new approach, and proponents of the traditional medical practices that had evolved over thousands of years in China. For the most part, this friction has been couched in the unexamined assumption that Western medicine is based on science, while Chinese medicine is not. This article will examine that assumption, which in this author’s opinion is unjustified and incorrect. Having practiced acupuncture for the past 50 years, after receiving my doctoral degrees in medicine and physiology, my thinking on this topic has also evolved over time. I will begin this article with some historical information that bears on the topic under discussion, followed by my personal ideas about how to resolve the confiicts that have arisen.

关键词： Science Chinese medicine Western medicine Resonance Constitution

When to repair a retinal detachment?

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 607-609页

作者： peter Wiedemann Medical Faculty Leipzig UniversityLeipzig 04103Germany

Rhegmatogenous retinal detachment(RRD)is the most common retinal emergency,threatening visual acuity,with an incidence of 1/10000[1].The number of RRDs is increasing[2-3].I recently had to prepare two expert reports a... 详细信息

关键词： RRD visual reports

Data driving design of high-entropy alloys for lightweight and dynamic applications

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 10-24页

作者： Kaixuan Cui Junwei Qiao peter KLiaw Yong Zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Materials Science and Engineering University of TennesseeKnoxville TN 37996USA

The topic of high-entropy alloys is one of the focus for both physics and materials ***-entropy alloys were usually defined as solid solution alloys,while the solid solution is different from the traditional terminal solid solution,because the solid solution without solvent element is the dominant *** discovery of high-entropy alloys greatly extended the composition space and the possibility of creating unique micro-and nano-level structures,which can meet the demands of lightweight and dynamic *** relationship between the phases and the parameters for the high-entropy alloys is rather *** data driving design can screen the specific high-entropy *** correlation between the composition and properties of highentropy alloys can be discovered by material genetic engineering and data science.

关键词： phase-formation rules materials genetic engineering lightweight high-entropy alloys dynamic properties