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Holographic Analysis Determines Proton and Neutron Masses from Electron Mass
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作者 T. R. Mongan 《Journal of Modern Physics》 2025年第2期341-346,共6页
The Standard Model of particle physics assumes that fundamental fermions are point particles with zero radius, no spatial dimensions, and infinite matter density. This alternative model treats the nine charged fundame... The Standard Model of particle physics assumes that fundamental fermions are point particles with zero radius, no spatial dimensions, and infinite matter density. This alternative model treats the nine charged fundamental fermions (three leptons and nine quarks) as spheres with non-zero holographic radius. Holographic analysis (based on quantum mechanics, general relativity, thermodynamics, and Shannon information theory) specifies electron mass by five fundamental constants: Planck’s constant ℏ, gravitational constant G, fine structure constant α, cosmological constant Λ, and vacuum energy fraction ΩΛ. Protons and neutrons are composite systems of up and down quarks. Describing forces between quark constituents confined within nucleons as inverse square attractive forces, this alternative model identifies composition factors Cpand Cnto relate proton and neutron masses to electron mass and thus to fundamental constants. An appendix summarizes holographic analyses characterizing astronomical masses at the opposite end of the mass scale for objects in the universe. 展开更多
关键词 Nucleon masses Electron mass Fundamental Constants
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Integrating UAV Photogrammetry and Thermal Infrared Entropy in Evaluating Rock Mass Characteristics
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作者 Xiaohan Zhao Wen Zhang +2 位作者 Junqi Chen Yaoyao Wang Qing Liu 《Journal of Earth Science》 2025年第4期1853-1866,共14页
0 INTRODUCTION Rock masses are inherently discontinuous,with fractures and joints governing their mechanical behavior and stability(Liu et al.,2024;Shang et al.,2018;Lisjak and Grasselli,2014;Scholtès and Donz... 0 INTRODUCTION Rock masses are inherently discontinuous,with fractures and joints governing their mechanical behavior and stability(Liu et al.,2024;Shang et al.,2018;Lisjak and Grasselli,2014;Scholtès and Donzé,2012;Jiang et al.,2009;Pine et al.,2006;Aydan et al.,1989). 展开更多
关键词 thermal infrared entropy rock masses rock mass characteristics UAV photogrammetry FRACTURES joints
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Atomic Mass Engineering of Ultra-High Thermal Conductivity in Large Bandgap Materials:A Case Study with Boron Arsenide
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作者 Tingting Wang Xiaozhe Li +4 位作者 Zhuo Ju Gang Zhang Dengke Ma Wu Li Lifa Zhang 《Chinese Physics Letters》 2025年第7期454-466,共13页
Heat dissipation highly relies on the thermal conductivity(κ)of materials.Materials with large bandgaps and signifcant atomic mass ratios,such as BAs,SiC,andθ-TaN,have attracted considerable attention due to their p... Heat dissipation highly relies on the thermal conductivity(κ)of materials.Materials with large bandgaps and signifcant atomic mass ratios,such as BAs,SiC,andθ-TaN,have attracted considerable attention due to their potential for achieving ultra-highκ,with BAs serving as a particularly representative example due to its unique combination of large bandgap and high thermal conductivity.In this paper,the efects of atomic mass modifcation on phonon bandgap andκare systematically investigated using a BAs model,accounting for both three-and four-phonon scattering processes.A 20%increase inκcan be obtained by substituting B,achieved through widening the phonon bandgap,which suppresses phonon scattering.Notably,the AAOO four-phonon scattering channel is more suppressed than the AAO three-phonon channel,leading to an increased phonon lifetime(τ).For As,κcan also be enhanced by 5%when replaced by lighter atoms,such as^(69)As,primarily due to the increased phonon group velocity(υ).We systematically clarify how atomic-mass-induced bandgap variations afectτ,υ,and thereforeκin wide-bandgap systems.Our work provides a specifc scheme for further improving the ultra-highκof materials with large bandgaps,which possesses great guiding signifcance. 展开更多
关键词 phonon bandgap phonon lifetime phonon scattering thermal conductivity atomic mass modifcation group velocity atomic mass engineering heat dissipation
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Advancements in Laboratory Studies of Layered Rock Masses for Deep Engineering:Insights and Future Perspectives
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作者 Yan Zhang Kai Meng +6 位作者 Xuanmei Fan Guoqing Chen Xiangsheng Zheng Shaojun Li Tianbin Li Peng Zeng Min Xia 《Journal of Earth Science》 2025年第3期1334-1340,共7页
Layered rock masses represent complex geological formations commonly encountered in the surrounding rock of deep engineering excavations(Hou et al.,2019;Xu et al.,2017;Yang C H et al.,2009;Xian and Tan,1989).These roc... Layered rock masses represent complex geological formations commonly encountered in the surrounding rock of deep engineering excavations(Hou et al.,2019;Xu et al.,2017;Yang C H et al.,2009;Xian and Tan,1989).These rock masses are predominantly composed of sedimentary,para-metamorphic,and volcanic rock types,characterized by a set of prominent,primary bedding structural planes(layers)exhibiting relatively consistent orientations and significant spatial continuity. 展开更多
关键词 surrounding rock rock masses deep engineering laboratory studies geological formations layered rock masses sedimentary rocks deep engineering excavations hou
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Optimizing distribution of multiple tuned mass dampers for building structures with inverse element exchange method
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作者 Peng-Tai Chan 《Earthquake Engineering and Engineering Vibration》 2025年第1期187-199,共13页
Multiple tuned mass dampers(MTMDs)reduce dynamic response with multiple specified frequencies of building structures.Many optimization algorithms for placement design exist,though they rarely conform to code-based ver... Multiple tuned mass dampers(MTMDs)reduce dynamic response with multiple specified frequencies of building structures.Many optimization algorithms for placement design exist,though they rarely conform to code-based verification nor produce high quality solutions without high computational effort and high complexity.This study proposes an inverse element exchange method(IEEM)with multi-level programming and compares it to a single tuned mass damper(STMD)and uniform distribution of multiple tuned mass dampers in the frequency and time domains.A ten-story shear building is used for the numerical case study.The results show that the proposed method can offer improvement over the STMD,uniform distribution of multiple tuned mass dampers,and distribution optimized by genetic algorithms(GA)with regard to minimizing the interstory drift ratio(IDR)in both the frequency and time domains and the time consumption for optimization. 展开更多
关键词 tuned mass damper multiple tuned mass damper optimal damper placement design transfer function
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Impact of regionally transported biomass burning on carbonaceous aerosol characterization,contribution and degradation in Pu'er,Southwest China
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作者 Jianwu Shi Wenjun Rao +8 位作者 Chenyang Zhao Li Deng Xinyu Han Wei Du Jianhong Huang Senlin Tian Ping Ning Jiming Hao Yaoqian Zhong 《Journal of Environmental Sciences》 2025年第12期710-723,共14页
Biomass burning(BB)emits carbonaceous aerosols that significantly influence air quality in Southwest China during spring.To further understand the characteristics of spring BB and its original contribution to organic ... Biomass burning(BB)emits carbonaceous aerosols that significantly influence air quality in Southwest China during spring.To further understand the characteristics of spring BB and its original contribution to organic carbon(OC),daily fine particulate matter(PM_(2.5))samples were collected from March to May 2022 in Pu'er,Southwest China.The concentrations of OC,elemental carbon(EC),levoglucosan(Lev),and potassium from BB(K+BB)during the study period ranged from 5.3 to 31.2μg/m^(3),0.86-13.1μg/m^(3),0.06-0.82μg/m^(3),and 0.05-2.88μg/m^(3),respectively.To eliminate the effects of Lev degradation,this study uses the Aging of Air Mass(AAM)index to correct the atmospheric concentration of Lev and combines Bayesian mixture modeling with a molecular tracer method to assess the original contribution of BB to OC.The results indicated that the AAM index was 0.18±0.05,indicating that the degradation of Lev reached 82%.When considering the degradation of levoglucosan in the atmosphere,the primary source of BB aerosols was crop-straw combustion(71.1%),followed by the combustion of certain hardwoods and softwoods(24.9%)and grasses(4.0%).The original contribution of BB to OC was 62.4%,which was much greater than the contribution when levoglucosan degradation(23.7%)was ignored.The air mass inverse trajectories and Moderate Resolution Imaging Spectroradiometer(MODIS)fire hotspots indicated that the BB plume from Southeast Asia during spring could influence PM_(2.5)long-range transport in remote locations,and the contribution could reach 82%in Southwest China. 展开更多
关键词 Biomass burning LEVOGLUCOSAN Carbonaceous aerosols Aging of Air mass(AAM) Bayesian mixture modeling
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Fto-dependent Vdac3 m6A Modification Regulates Neuronal Ferroptosis Induced by the Post-ICH Mass Effect and Transferrin 被引量:1
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作者 Zhongmou Xu Haiying Li +6 位作者 Xiang Li Jinxin Lu Chang Cao Lu Peng Lianxin Li John Zhang Gang Chen 《Neuroscience Bulletin》 2025年第6期970-986,共17页
During the hyperacute phase of intracerebral hemorrhage(ICH),the mass effect and blood components mechanically lead to brain damage and neurotoxicity.Our findings revealed that the mass effect and transferrin precipit... During the hyperacute phase of intracerebral hemorrhage(ICH),the mass effect and blood components mechanically lead to brain damage and neurotoxicity.Our findings revealed that the mass effect and transferrin precipitate neuronal oxidative stress and iron uptake,culminating in ferroptosis in neurons.M6A(N6-methyladenosine)modification,the most prevalent mRNA modification,plays a critical role in various cell death pathways.The Fto(fat mass and obesity-associated protein)demethylase has been implicated in numerous signaling pathways of neurological diseases by modulating m6A mRNA levels.Regulation of Fto protein levels in neurons effectively mitigated mass effect-induced neuronal ferroptosis.Applying nanopore direct RNA sequencing,we identified voltage-dependent anion channel 3(Vdac3)as a potential target associated with ferroptosis.Fto influenced neuronal ferroptosis by regulating the m6A methylation of Vdac3 mRNA.These findings elucidate the intricate interplay between Fto,Vdac3,m6A methylation,and ferroptosis in neurons during the hyperacute phase post-ICH and suggest novel therapeutic strategies for ICH. 展开更多
关键词 Intracerebral hemorrhage mass effect TRANSFERRIN Ferroptosis M6A methylation Vdac3
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An Analysis about the Origin and Essence of Mass Based on Particle-Propagating Model and Wave Equations of Scalar Waves 被引量:1
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作者 Jiang Jian-zhong Chen Xi-qi 《Journal of Environmental Science and Engineering(B)》 2025年第2期65-75,共11页
If the singularity of the cosmic Big Bang is taken as the origin of the reference coordinate system,the surrounding vacuum in the initial moments of it would exhibit radially-outward right-handed spiral motion at ligh... If the singularity of the cosmic Big Bang is taken as the origin of the reference coordinate system,the surrounding vacuum in the initial moments of it would exhibit radially-outward right-handed spiral motion at light speed.Based on this spatial motion hypothesis,we derive a unified field equation and a set of Maxwell’s equations for vacuum SWs(Scalar Waves)generating a huge spiral force field that drives the energy to spiral inwardly and distort,leading to the formation of mass.Furthermore,they also uncover that mass is fundamentally an ultimate expression of energy,manifesting as the result of spiral motion of space at light speed.And then,we indirectly validate the theory that coherent light waves’collision generate SWs and subsequently mass through the experiment verifying the Breit-Wheeler process.The establishment of our theory offers a new analytical tool for the exploration of mass origin,the cosmic Big Bang,unified field theories. 展开更多
关键词 QED(Quantum Electrodynamics) SW mass origin unified field theories
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Pulsed dynamic electrolysis enhanced PEMWE hydrogen production:Revealing the effects of pulsed electric fields on protons mass transport and hydrogen bubble escape 被引量:1
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作者 Xuewei Zhang Wei Zhou +13 位作者 Yuming Huang Liang Xie Tonghui Li Huimin Kang Lijie Wang Yang Yu Yani Ding Junfeng Li Jiaxiang Chen Miaoting Sun Shuo Cheng Xiaoxiao Meng Jihui Gao Guangbo Zhao 《Journal of Energy Chemistry》 2025年第1期201-214,共14页
The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for... The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for hydrogen production.Despite remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable obstacle.This impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles detachment.To address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis system.Compared to constant voltage electrolysis(hydrogen production rate:51.6 m L h^(-1),energy consumption:5.37 kWh Nm-^(3)H_(2)),this strategy(hydrogen production rate:66 m L h^(-1),energy consumption:3.83 kWh Nm-^(3)H_(2))increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic(PV)system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 V.The combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis(PDE)dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode surface.As such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport processes.This promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors. 展开更多
关键词 Water electrolysis Hydrogen production Pulsed dynamic electrolysis Proton exchange membrane water electrolysis mass transport
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Fat mass and obesity-associated protein in mesenchymal stem cells inhibits osteoclastogenesis via lnc NORAD/miR-4284 axis in ankylosing spondylitis 被引量:1
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作者 Wen-Jie Liu Jia-Xin Wang +9 位作者 Quan-Feng Li Yun-Hui Zhang Peng-Fei Ji Jia-Hao Jin Yi-Bin Zhang Zi-Hao Yuan Pei Feng Yan-Feng Wu Hui-Yong Shen Peng Wang 《World Journal of Stem Cells》 2025年第3期28-43,共16页
BACKGROUND Ankylosing spondylitis(AS)is recognized as a long-term inflammatory disorder that leads to inflammation in the spine and joints,alongside abnormal bone growth.In previous studies,we reported that mesenchyma... BACKGROUND Ankylosing spondylitis(AS)is recognized as a long-term inflammatory disorder that leads to inflammation in the spine and joints,alongside abnormal bone growth.In previous studies,we reported that mesenchymal stem cells(MSCs)derived from individuals with AS demonstrated a remarkable inhibition in the formation of osteoclasts compared to those obtained from healthy donors.The mechanism through which MSCs from AS patients achieve this inhibition remains unclear.AIM To investigate the potential underlying mechanism by which MSCs from individuals with ankylosing spondylitis(AS-MSCs)inhibit osteoclastogenesis.METHODS We analysed fat mass and obesity-associated(FTO)protein levels in AS-MSCs and MSCs from healthy donors and investigated the effects and mechanism by which FTO in MSCs inhibits osteoclastogenesis by coculturing and measuring the levels of tartrate-resistant acid phosphatase,nuclear factor of activated T cells 1 and cathepsin K.RESULTS We found that FTO,an enzyme responsible for removing methyl groups from RNA,was more abundantly expressed in MSCs from AS patients than in those from healthy donors.Reducing FTO levels was shown to diminish the capacity of MSCs to inhibit osteoclast development.Further experimental results revealed that FTO affects the stability of the long non-coding RNA activated by DNA damage(NORAD)by altering its N6-methyladenosine methylation status.Deactivating NORAD in MSCs significantly increased osteoclast formation by affecting miR-4284,which could regulate the MSC-mediated inhibition of osteoclastogenesis reported in our previous research.CONCLUSION This study revealed elevated FTO levels in AS-MSCs and found that FTO regulated the ability of AS-MSCs to inhibit osteoclast formation through the long noncoding RNA NORAD/miR-4284 axis. 展开更多
关键词 Ankylosing spondylitis Mesenchymal stem cells OSTEOCLASTOGENESIS Fat mass and obesity-associated protein Non-coding RNA activated by DNA damage
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A dopant-assisted iodide-adduct chemical ionization time-of-flight mass spectrometer based on VUV lamp photoionization for atmospheric low-molecular-weight organic acids analysis 被引量:1
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作者 Yonglei Zhang Ruidong Liu +3 位作者 Mei Li Yingzhe Guo Jichuang Kong Keyong Hou 《Journal of Environmental Sciences》 2025年第3期500-511,共12页
Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry.In iodine-adduct chemical ionizationmass spectrometry(CIMS),the low utilization efficiency of meth... Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry.In iodine-adduct chemical ionizationmass spectrometry(CIMS),the low utilization efficiency of methyl iodide and humidity interference are two major issues of the vacuum ultraviolet(VUV)lamp initiated CIMS for on-line gaseous formic and acetic acids analysis.In this work,we present a new CIMS based on VUV lamp,and the ion-molecular reactor is separated into photoionization and chemical ionization zones by a reducer electrode.Acetone was added to the photoionization zone,and the VUV photoionization acetone provided low-energy electrons for methyl iodide to generate I−,and the addition of acetone reduced the amount of methyl iodide by 2/3.In the chemical ionization zone,a headspace vial containing ultrapure water was added for humidity calibration,and the vial changes the sensitivity as a function of humidity from ambiguity to well linear correlation(R2>0.95).With humidity calibration,the CIMS can quantitatively measure formic and acetic acids in the humidity range of 0%-88%RH.In this mode,limits of detection of 10 and 50 pptv are obtained for formic and acetic acids,respectively.And the relative standard deviation(RSD)of quantitation stability for 6 days were less than 10.5%.This CIMS was successfully used to determine the formic and acetic acids in the underground parking and ambient environment of the Shandong University campus(Qingdao,China).In addition,we developed a simple model based formic acid concentration to assess vehicular emissions. 展开更多
关键词 Formic acid Acetic acid Vacuum ultraviolet(VUV)lamp photoionization(PI) Chemical ionization(CI) Time-of-flight mass spectrometry (TOFMS) Trace gases measurement
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Anterior mediastinal masses and thymic cysts
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作者 ÖnerÖzdemir 《World Journal of Clinical Cases》 SCIE 2025年第4期1-7,共7页
Cystic lesions of the anterior mediastinum in children suggest a well-known group of benign lesions that are comparatively frequent.Thymic cysts(TCs)are mostly positioned in the anterior mediastinum and some patients ... Cystic lesions of the anterior mediastinum in children suggest a well-known group of benign lesions that are comparatively frequent.Thymic cysts(TCs)are mostly positioned in the anterior mediastinum and some patients in the neck.Benign TCs classified as congenital intra-thoracic mesothelial cysts are commonly asymptomatic and have slight clinical significance.Multilocular TC,which can mimic another anterior mediastinal cystic tumor and is seen in adults,is more clinically important.It is a sporadic mediastinal lesion thought to arise in the course of acquired inflammation.Congenital mediastinal cysts represent 3%-6%of all mediastinal tumors and 10%-18%of radiologically reported mediastinal masses.Mediastinal TCs are uncommon and it is hard to know their true incidence.About 60%of cases with mediastinal TCs are asymptomatic,and the remainder of patients complains of nonspecific symptoms(e.g.,chest pain,dyspnea,or cough).The literature suggests that most cysts are benign,but an indefinite percentage may have a neoplastic process and result in significant compressive symptoms over time.Clinical symptoms of TCs vary depending on the location.In addition,frequent symptoms at the appearance of enlarged benign thymic and mediastinal cysts generally contain compressive symptoms(e.g.,respiratory distress,thymic pain,and symptoms related to Horner syndrome,hoarseness,dysphonia,dyspnea,orthopnea,wheezing,and fever).Many TCs have cystic density and a neat border and are simple to diagnose with radiological imaging.However,some TCs are hard to identify before surgery and may be misidentified as thymomas depending on their site and computed tomography results.Excision by thoracotomy,median sternotomy,or video-assisted techniques is essential for conclusive diagnosis,management,and abolition of relapse of anterior mediastinal masses and TCs.Histopathologic examination may be required after surgery.Considering the extent of the mass and the preliminary inability to make a definitive diagnosis,en bloc excision of the cyst was thought to be preferred to circumvent likely complications(e.g.,perforation,spillage of the contents,or incomplete excision). 展开更多
关键词 Mediastinal mass Thymic cyst Malignant tumor CYSTS THYMOMA Computer tomography
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Testing Validity of the Isobaric Multiplet Mass Equation in T=3 Isospin Septet
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作者 LIU Junhao HUA Xiang ZHAO Xi 《原子核物理评论》 北大核心 2025年第2期218-222,共5页
The validity of the isobaric multiplet mass equation(IMME)is of foundamental importance due to the basic concept of isospin.Recently,a serious breakdown was found in the A=54,T=3,isospin septet,the largest isospin sys... The validity of the isobaric multiplet mass equation(IMME)is of foundamental importance due to the basic concept of isospin.Recently,a serious breakdown was found in the A=54,T=3,isospin septet,the largest isospin system where the validity of IMME have been tested up to now.Inspired by this work,I revist the mass of some isobaric analogue states with the help of recent results from advanced mass measurement experiment.It is found that the IMME holds well in A=50 and 46 isospin septet and the coefficients of IMME also follow the systematic trends.Mass excess value for^(50)Ni and^(46)Fe,is predicted to be-3932(20)keV and 898(67)keV,respectively. 展开更多
关键词 ISOSPIN IMME nuclear mass βdecay proton drip-line
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It’s Not Always What You Think It Is—A Case of a Thumb Mass Found to Be a Schwannoma
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作者 Harin B. Parikh Deeti J. Pithadia +1 位作者 Bonnie L. Balzer Stuart H. Kuschner 《Open Journal of Orthopedics》 2025年第2期102-109,共8页
Soft tissue tumors in the hand have a broad differential diagnosis. Included in the list of differential diagnoses for these tumors are Schwannomas, which are benign tumors within the peripheral nervous system [1]. Sc... Soft tissue tumors in the hand have a broad differential diagnosis. Included in the list of differential diagnoses for these tumors are Schwannomas, which are benign tumors within the peripheral nervous system [1]. Schwannomas are uncommon within the upper extremity, and they are exceedingly rare within the hand and wrist [1]. We describe a case of an 80-year-old female presented with a soft tissue mass within her right thumb. She underwent excisional biopsy of the mass, and pathology showed features consistent with schwannoma. She had resolution of her symptoms thereafter. We discuss the differential diagnosis for soft-tissue tumors in this location. When assessing patients with soft tissue tumors of the hand and wrist, it is important for the treating provider to maintain a broad differential diagnosis in order to facilitate appropriate management of these lesions. 展开更多
关键词 massES TUMORS SCHWANNOMA THUMB Upper Extremity
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Design and Optimization of Terracotta Tube-Based Direct Evaporative Cooling Exchanger: An Analytical Approach to Heat and Mass Transfer
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作者 Windnigda Zoungrana Makinta Boukar +2 位作者 Ousmane Coulibaly Guy Christian Tubreoumya Antoine Bere 《Open Journal of Applied Sciences》 2025年第1期352-373,共22页
This study develops an analytical model to evaluate the cooling performance of a porous terracotta tubular direct evaporative heat and mass exchanger. By combining energy and mass balance equations with heat and mass ... This study develops an analytical model to evaluate the cooling performance of a porous terracotta tubular direct evaporative heat and mass exchanger. By combining energy and mass balance equations with heat and mass transfer coefficients and air psychrometric correlations, the model provides insights into the impact of design and operational parameters on the exchanger cooling performance. Validated against an established numerical model, it accurately simulates cooling behavior with a Root Mean Square Deviation of 0.43 - 1.18˚C under varying inlet air conditions. The results show that tube geometry, including equivalent diameter, flatness ratio, and length significantly influences cooling outcomes. Smaller diameters enhance wet-bulb effectiveness but reduce cooling capacity, while increased flatness and length improve both. For example, extending the flatness ratio of a 15 mm diameter, 0.6 m long tube from 1 (circular) to 4 raises the exchange surface area from 0.028 to 0.037 m2, increasing wet-bulb effectiveness from 60% to 71%. Recommended diameters range from 5 mm for tubes under 0.5 m to 1 cm for tubes 0.5 to 1 m in length. Optimal air velocities depend on tube length: 1 m/s for tubes under 0.8 m, 1.5 m/s for lengths of 0.8 to 1.2 m, and up to 2 m/s for longer tubes. This model offers a practical alternative to complex numerical and CFD methods, with potential applications in cooling tower optimization for thermal and nuclear power plants and geothermal heat exchangers. 展开更多
关键词 Analytical Modeling Porous Terracotta Tube Direct Evaporative Cooling Heat and mass Exchanger Performance Optimization
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Seismic performance evaluation of mass timber buildings equipped with resilient and conventional friction devices
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作者 Ashkan Hashemi Rajnil Lal 《Resilient Cities and Structures》 2025年第2期103-115,共13页
The application of mass timber elements in different structures has gained publicity over the last few years,pri-marily due to climate change adaptation policies and net zero carbon targets.Timber is a renewable const... The application of mass timber elements in different structures has gained publicity over the last few years,pri-marily due to climate change adaptation policies and net zero carbon targets.Timber is a renewable construction material that can outperform other building materials regarding environmental impact.However,when used in seismically active regions,its application has been limited due to the uncertainties on their seismic behaviour in respect with different design standards and limited ductility in conventional connections.Conventional timber connections typically suffer from stiffness and strength degradation under cyclic loads.Their repairability is also low due to permanent damage in the fasteners and the associated crushing in the wood fibres.The use of friction connections can be an efficient way to mitigate these issues.They offer many advantages as they are economical and yet provide a high level of reliable and continuous energy dissipation.In recent years,a new generation of friction connections has been developed that can provide self-centring behaviour(i.e.,the ability of the structure to return to its original position at the end of an earthquake).However,how these connections perform compared to a mass timber system with conventional timber connections is still unknown.Several studies in the literature have suggested that these connections can enhance the performance of mass timber structures.However,the seismic performance of such systems specifically in terms of base shear,response drifts and response accelerations-has not been thoroughly investigated.This paper examines various design aspects of conventional friction connections and self-centring friction connections,providing insights into their differences concerning key seismic performance indicators.It compares the seismic performance of mass timber buildings equipped with both solutions,highlighting their advantages and limitations and drawing conclusions based on the results.The key findings are that friction connections can provides a superior seismic performance for timber structures.However,that may need to be combined with a parallel system avoid residual displacements. 展开更多
关键词 mass timber RESILIENCE DAMPERS FRICTION Energy dissipation
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Mass spectrometry for non-destructive detection of the average diameter of micro copper wires
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作者 Rui Su Xiaowei Fang +5 位作者 Peng Zeng Yong Qian Xuanzhu Li Huiyu Xing Jiamei Lin Jiaquan Xu 《Chinese Chemical Letters》 2025年第10期474-477,共4页
The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or... The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or damage has always been a technical concern for production enterprises.Herein,a novel approach was developed for nondestructive detection of the average diameter at any given segment of a long copper wire by assessing the adsorption capacity of arginine on its surface.The amount of adsorbent on the surface of the copper wire exhibits a positive correlation with the area,which can be detected by extractive electrospray ionization mass spectrometry(EESI-MS)after online elution with ammonia.The experimental results demonstrated that the analysis can be completed within 15 min,with a good linear relationship between copper wires with different diameters and the adsorption capacity of arginine.The linear correlation coefficient R2was 0.995,the relative standard deviation was 1.10%-2.81%,and the detection limit reached 2.5μm(length of segment=4 cm),showing potential applications for facile measurement of the average diameter of various metal wires. 展开更多
关键词 Measurement of diameter mass spectrometry Non-destructive detection Copper wire Average diameter Measurement of diameter mass spectrometry Non-destructive detection Copper wire Average diameter
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Association of Body Mass Index with All-Cause Mortality and Cause-Specific Mortality in Rural China:10-Year Follow-up of a Population-Based Multicenter Prospective Study
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作者 Juanjuan Huang Yuanzhi Di +29 位作者 Lingyu Shen Jianguo Liang Jiang Du Xuefang Cao Weitao Duan Aiwei He Jun Liang Limei Zhu Zisen Liu Fang Liu Shumin Yang Zuhui Xu Cheng Chen Bin Zhang Jiaoxia Yan Yanchun Liang Rong Liu Tao Zhu Hongzhi Li Fei Shen Boxuan Feng Yijun He Zihan Li Yaqi Zhao Tonglei Guo Liqiong Bai Wei Lu Qi Jin Lei Gao Henan Xin 《Biomedical and Environmental Sciences》 2025年第10期1179-1193,共15页
Objective This study aimed to explore the association between body mass index(BMI)and mortality based on the 10-year population-based multicenter prospective study.Methods A general population-based multicenter prospe... Objective This study aimed to explore the association between body mass index(BMI)and mortality based on the 10-year population-based multicenter prospective study.Methods A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023.Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality.Stratified analyses were performed based on the individual characteristics of the participants.Results Overall,19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died.The underweight(<18.5 kg/m^(2))presented an increase in all-cause mortality(adjusted hazards ratio[aHR]=2.00,95%confidence interval[CI]:1.66–2.41),while overweight(≥24.0 to<28.0 kg/m^(2))and obesity(≥28.0 kg/m^(2))presented a decrease with an aHR of 0.61(95%CI:0.52–0.73)and 0.51(95%CI:0.37–0.70),respectively.Overweight(aHR=0.76,95%CI:0.67–0.86)and mild obesity(aHR=0.72,95%CI:0.59–0.87)had a positive impact on mortality in people older than 60 years.All-2 cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m(aHR=0.95,95%CI:0.92–0.98)and increased slightly above that value,indicating a U-shaped association.The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses.Conclusion This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years.Therefore,it is essential to consider age differences when formulating health and weight management strategies. 展开更多
关键词 Body mass index Mortality OVERWEIGHT Prospective study UNDERWEIGHT
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Mass Produced Flexible Aramid Electrodes Via Delamination of Layered Aerogels for Cut-to-Fit Wearable Zinc–Air Batteries Encased in Aramid Protection
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作者 Seung Hee Park Sin Yeong Jang Sung Hoon Ahn 《Energy & Environmental Materials》 2025年第1期92-105,共14页
This study introduces a cut-to-fit methodology for customizing bulk aramid aerogels into form factors suitable for wearable energy storage.Owing to strong intercomponent bonds within aramid-based building blocks,it is... This study introduces a cut-to-fit methodology for customizing bulk aramid aerogels into form factors suitable for wearable energy storage.Owing to strong intercomponent bonds within aramid-based building blocks,it is possible to delaminate layered bulk aerogel into flexible and thinner sheets,enabling efficient mass production.This process allows for precise customization of aerogel dimensions,shape,and elasticity,ensuring high resilience to deformation along with excellent thermal and impact resistance.Incorporation of conductive carbon nanotubes on the surface significantly enhances electrical conductivity and multi-catalytic activity while retaining the inherent advantages of aramids.These advancements facilitate the use of flexible and conductive electrodes as air cathodes in solid-state zinc–air batteries(ZABs),which demonstrate superior cyclic performance and lifecycles exceeding 160 h.Furthermore,aramid-based packaging provides superior protection for pouch-type ZABs,ensuring a consistent power supply even in severe conditions.These batteries are capable of withstanding structural deformations and absorbing physical and thermal shocks,such as impacts and exposure to fire.Moreover,the innovative reassembly of custom-cut single-pouch cells into battery modules allows for enhanced power output,tailored to wearable applications.This highlights the potential of the technology for a wide array of wearable devices requiring dependable energy sources in demanding environments. 展开更多
关键词 aramid nanofibers layer-structured mass production solid-state batteries super-elasticity
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Mass spectral database-based methodologies for the annotation and discovery of natural products
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作者 Fengyao Yang Zeyuan Liang +4 位作者 Haoran Zhao Jiayi Zheng Lifang Liu Huipeng Song Guizhong Xin 《Chinese Journal of Natural Medicines》 2025年第4期410-420,共11页
Natural products(NPs)have long held a significant position in various fields such as medicine,food,agriculture,and materials.The chemical space covered by NPs is extensive but often underexplored.Therefore,high-throug... Natural products(NPs)have long held a significant position in various fields such as medicine,food,agriculture,and materials.The chemical space covered by NPs is extensive but often underexplored.Therefore,high-throughput and efficient methodologies for the annotation and discovery of NPs are desired to address the complexity and diversity of NP-based systems.Mass spectrometry(MS)has emerged as a powerful platform for the annotation and discovery of NPs.MS databases provide vital support for the structural characterization of NPs by integrating extensive mass spectral data and sample information.Additionally,the released annotation methodologies,based on a variety of informatics tools,continuously improve the ability to annotate the structure and properties of compounds.This review examines the current mainstream databases and annotation methodologies,focusing on their advantages and limitations.Prospects for future technological advancements are then discussed in terms of novel applications and research objectives.Through a systematic overview,this review aims to provide valuable insights and a reference for MS-based NPs annotation,thereby promoting the discovery of novel natural entities. 展开更多
关键词 mass spectrometry Natural products ANNOTATION DATABASES
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