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Momentum as Translations at Conformal Infinity

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1522-1540页

作者： richard james petti Jacob Luke Graham Arlington MA USA Newton MA USA

Although General Relativity is the classic example of a physical theory based on differential geometry, the momentum tensor is the only part of the field equation that is not derived from or interpreted with differential geometry. This work extends General Relativity and Einstein-Cartan theory by augmenting the Poincaré group with projective (special) conformal transformations, which are translations at conformal infinity. Momentum becomes a part of the differential geometry of spacetime. The Lie algebra of these transformations is represented by vectorfields on an associated Minkowski fiber space. Variation of projective conformal scalar curvature generates a 2-index tensor that serves as linear momentum in the field equations of General Relativity. The computation yields a constructive realization of Mach’s principle: local inertia is determined by local motion relative to mass at conformal infinity in each fiber. The vectorfields have a cellular structure that is similar to that of turbulent fluids.

关键词： Projective Symmetry Conformal Symmetry Momentum General Relativity Einstein-Cartan Mach’s Principle

Surgical management of the diabetic foot:The current evidence

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World Journal of Orthopedics 2024年第5期15卷 404-417页

作者： richard Henry Randall Roberts Gareth Rhys Davies-Jones james Brock Vaishnav Satheesh Greg AJ Robertson Department of Trauma and Orthopaedics Wrexham Maelor HospitalWrexham LL137TDUnited Kingdom Department of Trauma and Orthopaedics The Robert Jones and Agnes Hunt Orthopaedic HospitalOswestry SY107AGUnited Kingdom

The prevalence of diabetes mellitus and its associated complications,particularly diabetic foot pathologies,poses significant healthcare challenges and economic burdens *** review synthesises current evidence on the surgical management of the diabetic foot,focusing on the interplay between neuropathy,ischemia,and infection that commonly culminates in ulcers,infections,and,in severe cases,*** escalating incidence of diabetes mellitus underscores the urgency for effective management strategies,as diabetic foot complications are a leading cause of hospital admissions among diabetic patients,significantly impacting morbidity and mortality *** review explores the pathophysiological mechanisms underlying diabetic foot complications and further examines diabetic foot ulcers,infections,and skeletal pathologies such as Charcot arthropathy,emphasising the critical role of early diagnosis,comprehensive management strategies,and interdisciplinary care in mitigating adverse *** addressing surgical interventions,this review evaluates conservative surgeries,amputations,and reconstructive procedures,highlighting the importance of tailored approaches based on individual patient profiles and the specific characteristics of foot *** integration of advanced diagnostic tools,novel surgical techniques,and postoperative care,including offloading and infection control,are discussed in the context of optimising healing and preserving limb function.

关键词： Diabetes Diabetic foot Charcot Osteomyelitis Amputation Diabetic foot attack Conservative surgery

CD8+T cell metabolic flexibility elicited by CD28-ARS2 axisdriven alternative splicing of PKM supports antitumor immunity

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Cellular & Molecular Immunology 2024年第3期21卷 260-274页

作者： G.Aaron Holling Colin A.Chavel Anand P.Sharda Mackenzie M.Lieberman Caitlin M.james Shivana M.Lightman Jason H.Tong Guanxi Qiao Tiffany R.Emmons Thejaswini Giridharan Shengqi Hou Andrew M.Intlekofer richard M.Higashi Teresa W.M.Fan Andrew N.Lane Kevin H.Eng Brahm H.Segal Elizabeth A.Repasky Kelvin P.Lee Scott H.Olejniczak Department of Immunology Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA Department of Medicine Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA Human Oncology and Pathogenesis Program Memorial Sloan Kettering Cancer CenterNew YorkNY 10065USA Center for Environmental Systems Biochemistry Department of Toxicology and Cancer Biology and Markey Cancer CenterLexingtonKY 40536USA Department of Cancer Genetics and Genomics Roswell Park Comprehensive Cancer CenterBuffaloNY 14263USA Present address:University of Colorado Boulder BoulderCO 80309USA Present address:Dana Farber Cancer Institute BostonMA 02215USA Present address:Massachusetts Institute of Technology BostonMA 02139USA Present address:Melvin and Bren Simon Comprehensive Cancer Center Indiana University School of MedicineIndianapolisIN 46202USA

Metabolic flexibility has emerged as a critical determinant of CD8+T-cell antitumor activity,yet the mechanisms driving the metabolic flexibility of T cells have not been *** this study,we investigated the influence of the nuclear cap-binding complex(CBC)adaptor protein ARS2 on mature T *** doing so,we discovered a novel signaling axis that endows activated CD8+T cells with flexibility of glucose ***2 upregulation driven by CD28 signaling reinforced splicing factor recruitment to pre-mRNAs and affected approximately one-third of T-cell activation-induced alternative splicing *** these effects,the CD28-ARS2 axis suppressed the expression of the M1 isoform of pyruvate kinase in favor of PKM2,a key determinant of CD8+T-cell glucose utilization,interferon gamma production,and antitumor effector ***,PKM alternative splicing occurred independently of CD28-driven PI3K pathway activation,revealing a novel means by which costimulation reprograms glucose metabolism in CD8+T cells.

关键词： Immunometabolism mRNA splicing CD8 T cells ARS2 PKM2

Design of soft magnetic materials

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npj Computational Materials 2022年第1期8卷 17-26页

作者： Ananya Renuka Balakrishna richard D.james Aerospace and Mechanical Engineering University of Southern CaliforniaLos AngelesCA90089USA Aerospace and Engineering Mechanics University of MinnesotaMinneapolisMN55455USA

We present a strategy for the design of ferromagnetic materials with exceptionally low magnetic hysteresis,quantified by *** this strategy,we use a micromagnetic algorithm that we have developed in previous research and which has been validated by its success in solving the“Permalloy Problem”—the well-known difficulty of predicting the composition 78.5%Ni of the lowest coercivity in the Fe–Ni system—and by the insight it provides into the“Coercivity Paradox”of ***,the design strategy predicts that cubic materials with large saturation magnetization ms and large magnetocrystalline anisotropy constant κ_(1) will have low coercivity on the order of that of Permalloy,as long as the magnetostriction constantsλ_(100),λ_(111)are tuned to special *** explicit prediction for a cubic material with low coercivity is the dimensionless number(c_(11)−c_(12))λ_(100)^(2)/(2_(κ_(1)))=81 for〈100〉easy *** results would seem to have broad potential application,especially to magnetic materials of interest in energy research.

关键词： magnetic cubic exceptional

Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)

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Nuclear Science and Techniques 2024年第8期35卷 142-152页

作者： Yin‑Ji Chen Hao Zhang Li‑Yong Zhang Jian‑Jun He richard james deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue Li Jian‑Guo Wang Long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang Luo‑Huan Wang Zi‑Ming Li Lu‑Yang Song Liang‑Ting Sun Qi Wu Jia‑Qing Li Bao‑Qun Cui Li‑Hua Chen Rui‑Gang Ma Er‑Tao Li Gang Lian Yao‑De Sheng Zhi‑Hong Li Bing Guo Wei‑Ping Liu Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Department of Physics and Astronomy The Joint Institute for Nuclear AstrophysicsUniversity of Notre DameNotre DameIN 46556USA School of Physics and Astronomy Monash UniversityClaytonVIC 3800Australia Facility for Rare Isotope Beams Michigan State UniversityEast LansingMI 48824USA Institute of Nuclear and Particle Physics and Department of Physics and Astronomy Ohio UniversityAthensOH 45701USA Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China China Institute of Atomic Energy Beijing 102413China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China College of Science Southern University of Science and TechnologyShenzhen 518055China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Key Laboratory of Nuclear Physics and Ion‑Beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China School of Mathematics and Physics Handan UniversityHandan 056005China

Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in *** one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest ***,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium *** performed a direct measurement of this break-out reaction at the China Jinping underground *** measurement was performed down to the low-energy limit of E_(c.m.)=186 keV in the center-of-mass *** key resonance was observed at 225.2 keV for the first *** a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRE *** is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously *** break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars.

关键词： Nuclear astrophysics First stars Abundance of calcium Reaction cross section Reaction rate China Jinping underground laboratory(CJPL) JUNA

Seismic performance of steel MRF building with nonlinear viscous dampers

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 254-271页

作者： Baiping DONG james M. RICLES richard SAUSE ATLSS Engineering Research Center Department of Civil and Environmental Engineering Lehigh University Bethlehem PA 18015 USA

This paper presents an experimental study of the seismic response of a 0.6-scale three-story seismicresistant building structure consisting of a moment resisting frame （MRF） with reduced beam sections （RBS）, and a frame with nonlinear viscous dampers and associated bracing （called the DBF）. The emphasis is on assessing the seismic performance for the design basis earthquake （DBE） and maximum considered earthquake （MCE）. Three MRF designs were studied, with the MRF designed for 100%, 75%, and 60%, respectively, of the required base shear design strength determined according to ASCE 7-10. The DBF with nonlinear viscous dampers was designed to control the lateral drift demands. Earthquake simulations using ensembles of DBE and MCE ground motions were conducted using the real-time hybrid simulation method. The results show the drift demand and damage that occurs in the MRF under seismic loading. Overall, the results show that a high level of seismic performance can be achieved under DBE and MCE ground motions, even for a building structure designed for as little as 60% of the base shear design strength required by ASCE 7-10 for a structure without dampers.

关键词： seismic response steel MRF nonlinear viscous damper design basis earthquake real-time hybrid simulation

Porphyria cutanea tarda as a complication of therapy for chronic hepatitis C

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World Journal of Gastroenterology 2008年第38期14卷 5913-5915页

作者： james Azim Heather McCurdy richard H Moseley Division of Gastroenterology Department of Internal Medicine Department of Veterans Affairs Medical Center and University of Michigan School of Medicine Ann ArborMichigan United States

There is a strong association between porphyria cutanea tarda (PCT) and chronic viral hepatitis C. Therapy for chronic viral hepatitis C may improve PCT. However, there are only a few reports of the de novo development of PCT during therapy for chronic viral hepatitis C. We describe the development of PCT in a 56-year-old patient with chronic viral hepatitis C after 12 wk of peginterferon/ribavirin therapy. In addition, the patient was homozygous for the H63D hereditary hemochromatosis gene (HFE ) mutation. The association of PCT with chronic viral hepatitis C and the possible role of hepatic iron overload and ribavirin-induced hemolytic anemia in the development of PCT during therapy for chronic viral hepatitis C are discussed.

关键词： Porphyria Hepatitis C virus Ribavirin Pegylated interferon Hemochromatosis

A Cilia-inspired Closed-loop Sensor-actuator Array

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Journal of Bionic Engineering 2018年第3期15卷 526-532页

作者： james G. H. Whiting richard Mayne Chris Melhuish Andrew Adamatzky Unconventional Computing Centre and Bristol Robotics Laboratory University of the West of England Bristol UK

Cilia are finger-like cell-surface organelles that are used by certain varieties of aquatic unicellular organisms for motility, sensing and obj ect manipulation. Initiated by internal generators and external mechanical and chemical stimuli, coordinated undulations of cilia lead to the motion of a fluid surrounding the organism. This motion transports micro-particles towards an oral cavity and provides motile force. Inspired by the emergent properties of cilia possessed by the pond organism P. caudatum, we propose a novel smart surface with closed-loop control using sensor-actuators pairings that can manipulate objects. Each vibrating motor actuator is controlled by a localised microcontroller which utilises proximity sensor information to initiate actuation. The circuit boards are designed to be plug-and-play and are infinitely up-scalable and reconfigurable. The smart surface is capable of moving objects at a speed of 7.2 millimetres per second in forward or reverse direction. Further development of this platform will include more anatomically similar biomimetic cilia and control.

关键词： bioinspiration artificial cilia object manipulation sorting platforms

Intracellular Transport of Plant Viruses： Finding the Door out of the Cell

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Molecular Plant 2011年第5期4卷 813-831页

作者： james E. Schoelz Phillip A. Harries richard S. Nelson Division of Plant Sciences University of Missouri Columbia MO 65211 USA Department of Biology Pittsburg State University Pittsburg KS 66762 USA Plant Biology Division The Samuel Roberts Noble Foundation Inc. Ardmore OK 73401 USA

Plant viruses are a class of plant pathogens that specialize in movement from cell to cell. As part of their arsenal for infection of plants, every virus encodes a movement protein （MP）, a protein dedicated to enlarging the pore size of plasmodesmata （PD） and actively transporting the viral nucleic acid into the adjacent cell. As our knowledge of intercellular transport has increased, it has become apparent that viruses must also use an active mechanism to target the virus from their site of replication within the cell to the PD. Just as viruses are too large to fit through an unmodified plasmodesma, they are also too large to be freely diffused through the cytoplasm of the cell. Evidence has accumulated now for the involvement of other categories of viral proteins in intracellular movement in addition to the MP, including viral proteins originally associated with replication or gene expression. In this review, we will discuss the strategies that viruses use for intracellular movement from the replication site to the PD, in particular focusing on the role of host membranes for intracellular transport and the coordinated interactions between virus proteins within cells that are necessary for successful virus spread.

关键词： Macromolecular trafficking membrane biology membrane proteins movement proteins plasmodesmata plant-virus interactions.