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An Automatic Fuzzy Clustering Algorithm for Discrete Elements

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Journal of the Operations Research Society of China 2023年第2期11卷 309-325页

作者： Tai Vovan Yen Nguyenhoang Sang Danh college of Natural Science Can Tho UniversityCan Tho cityVietnam Nguyen Trung Truc college Rach Gia cityVietnam

This research proposes a measure called cluster similar index(CSI)to evaluate the similarity of cluster for discrete elements.The CSI is used as a criterion to build the automatic fuzzy clustering algorithm.This algorithm can determine the suitable number of clusters,find the elements in each cluster,give the probability to belong to the clusters of each element,and evaluate the quality of the established clusters at the same time.The proposed algorithm can perform quickly and effectively by the established MATLAB procedure.Several numerical examples illustrate the proposed algorithm and show the advantages in comparing with the existing ones.Finally,applying the proposed algorithm in the image recognition shows potentiality in the reality of this research.

关键词： Cluster analysis Distance Image Similar index

Coupled Numerical Simulation of Electromagnetic and Flow Fields in a Magnetohydrodynamic Induction Pump

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Fluid Dynamics & Materials Processing 2024年第4期20卷 889-899页

作者： He Wang Ying He college of Transportation Ludong UniversityYantai264025China college of Intelligent Manufacturing City College of HuizhouHuizhou516025China

Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh environments.The rate of fluid flow through the pump directly affects the efficiency and stability of the device.To explore the influence of induction pump settings on the related delivery speed,in this study,a numerical model for coupled electromagnetic and flow field effects is introduced and used to simulate liquid metal lithium flow in the induction pump.The effects of current intensity,frequency,coil turns and coil winding size on the velocity of the working fluid are analyzed.It is shown that the first three parameters have a significant impact,while changes in the coil turns have a negligible influence.The maximum increase in working fluid velocity within the pump for the parameter combination investigated in this paper is approximately 618%.As the frequency is increased from 20 to 60 Hz,the maximum increase in the mean flow rate of the working fluid is approximately 241%.These research findings are intended to support the design and optimization of these devices.

关键词： Magnetic fluid multi-physical field coupling induction pump numerical simulation liquid metal conveying

A medium chain fatty acid, 6-hydroxyhexanoic acid (6-HHA), protects against obesity and insulin resistance

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1892-1894页

作者： Sara C.Sebag Meihua Hao Qingwen Qian Chawin Upara Qiong Ding Min Zhu Jeffrey A.Banas Huojun Cao Liu Hong Ling Yang Department of Anatomy and Cell Biology University of Iowa Carver College of MedicineIowa CityIA 52242USA Fraternal Order of Eagles Diabetes Research Center University of Iowa Carver College of MedicineIowa CityIA 52242USA Pappajohn Biomedical Institute University of Iowa Carver College of MedicineIowa CityIA 52242USA Iowa Institute for Oral Health Research University of Iowa College of DentistryIowa CityIA 52242USA

To the Editor,Obesity,one of the most serious health concerns worldwide,exacerbates periodontitis pathogenesis and reduces the effectiveness of treatments1.Conversely,periodontitis-associated inflammation disrupts systemic lipid and glucose homeostasis,the major risk factors for developing obesity-associated pathologies1.Accumulated studies have demonstrated that certain supplemental dietary lipids such as dietary polyunsaturated fatty acids,have beneficial outcomes for diabetic and obese patients.In addition to dietary lipid supply,the oral and gut microbiota produce fatty acids(FAs)which provide the host with essential nutrients and aid in defense against pathogens.Hydroxyhexanoic medium chain FAs(MCFAs;6–12 carbons)are bacterial-derived lipids shown to have anti-inflammatory and insulin sensitization effects in diverse cell types such as hepatocytes2.However,whether and to what extent oral microbiota-produced MCFAs may ameliorate obesity-associated metabolic dysfunction are largely unknown.

关键词： obesity dietary lipids

Investigations on mesa width design for 4H–SiC trench super junction Schottky diodes

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Chinese Physics B 2018年第8期27卷 466-475页

作者：仲雪倩王珏王宝柱王珩宇郭清盛况 college of Electrical Engineering Zhejiang University college of Information and Electrical Engineering Zhejiang University City College

Mesa width （WM） is a key design parameter for SiC super junction （SJ） Schottky diodes （SBD） fabricated by the trench-etching-and-sidewall-implant method. This paper carries out a comprehensive investigation on how the mesa width design determines the device electrical performances and how it affects the degree of performance degradation induced by process variations. It is found that structures designed with narrower mesa widths can tolerant substantially larger charge imbalance for a given BV target, but have poor specific on-resistances. On the contrary, structures with wider mesa widths have superior on-state performances but their breakdown voltages are more sensitive to p-type doping variation. Medium WM structures （-2 p.m） exhibit stronger robustness against the process variation resulting from SiC deep trench etching. Devices with 2-p.m mesa width were fabricated and electrically characterized. The fabricated SiC SJ SBDs have achieved a breakdown voltage of 1350 V with a specific on-resistance as low as 0.98 mΩ2.cm2. The estimated specific drift on- resistance by subtracting substrate resistance is well below the theoretical one-dimensional unipolar limit of SiC material. The robustness of the voltage blocking capability against trench dimension variations has also been experimentally verified for the proposed SiC SJ SBD devices.

关键词： silicon carbide super junction Schottky diode trench etching

An Effective Runge-Kutta Optimizer Based on Adaptive Population Size and Search Step Size

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Computers, Materials & Continua 2023年第9期76卷 3443-3464页

作者： Ala Kana Imtiaz Ahmad Department of Computer Engineering College of Engineering and PetroleumKuwait UniversityKuwait CityKuwait

A newly proposed competent population-based optimization algorithm called RUN,which uses the principle of slope variations calculated by applying the Runge Kutta method as the key search mechanism,has gained wider interest in solving optimization problems.However,in high-dimensional problems,the search capabilities,convergence speed,and runtime of RUN deteriorate.This work aims at filling this gap by proposing an improved variant of the RUN algorithm called the Adaptive-RUN.Population size plays a vital role in both runtime efficiency and optimization effectiveness of metaheuristic algorithms.Unlike the original RUN where population size is fixed throughout the search process,Adaptive-RUN automatically adjusts population size according to two population size adaptation techniques,which are linear staircase reduction and iterative halving,during the search process to achieve a good balance between exploration and exploitation characteristics.In addition,the proposed methodology employs an adaptive search step size technique to determine a better solution in the early stages of evolution to improve the solution quality,fitness,and convergence speed of the original RUN.Adaptive-RUN performance is analyzed over 23 IEEE CEC-2017 benchmark functions for two cases,where the first one applies linear staircase reduction with adaptive search step size(LSRUN),and the second one applies iterative halving with adaptive search step size(HRUN),with the original RUN.To promote green computing,the carbon footprint metric is included in the performance evaluation in addition to runtime and fitness.Simulation results based on the Friedman andWilcoxon tests revealed that Adaptive-RUN can produce high-quality solutions with lower runtime and carbon footprint values as compared to the original RUN and three recent metaheuristics.Therefore,with its higher computation efficiency,Adaptive-RUN is a much more favorable choice as compared to RUN in time stringent applications.

关键词： Optimization Runge Kutta(RUN) metaheuristic algorithm exploration exploitation population size adaptation adaptive search step size

Loading calcium fluorescent probes into protoplasts to detect calcium in the flesh tissue cells of Malus domestica

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Horticulture Research 2020年第1期7卷 1561-1571页

作者： Lina Qiu Yongzhang Wang Haiyong Qu college of Horticulture Qingdao Agricultural UniversityQingdao CityChina

Cytosolic Ca^(2+)plays a key role in signal transduction in plants.Calcium imaging is the most common approach to studying dynamic changes in the cytoplasmic Ca^(2+)content.Here,we used mature‘Fuji’apples(Malus pumila Mill.)to obtain viable protoplasts from flesh tissue cells by enzymatic hydrolysis;then,three small-molecule fluorescent probes(fluo-8/AM,fluo-4/AM,and rhod-2/AM)were loaded into the protoplasts.All three Ca^(2+)fluorescent probes successfully entered the cytoplasm but did not enter the vacuole.Both the Ca^(2+)chelator(EGTA)and Ca^(2+)channel blocker(La3+)reduced the fluorescence intensity in the cytoplasm.The calcium ionophore A23187 increased the fluorescence intensity in the cytoplasm at 5μmol/L but decreased it at 50μmol/L.Additionally,A23187 reversed the fluorescence intensity in the cytoplasm,which was decreased by La3+.Ionomycin is also a calcium ionophore that can increase the fluorescence intensity of calcium in the cytoplasm.These results suggest that small-molecule Ca^(2+)fluorescent probes can be used to detect changes in cytosolic calcium levels in the cells of fruit flesh tissue.In addition,the optimum concentration of fluo-8/AM was determined to be 5μmol/L.This was the first time that protoplasts have been isolated from apple flesh tissue cells and small-molecule fluorescent probes have been used to detect calcium in the cytoplasm of flesh tissue cells.This study provides a new method to study calcium signal transduction in fruit flesh tissue.

关键词： reversed probes hydrolysis

Down in the Dump:The Abject in Alice Notley’s Culture of One

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Journal of Foreign Languages and Cultures 2019年第1期3卷 127-137页

作者： Laura Hinton The city college of New York

Alice Notley’s Culture of On e(2011)is a“poet’s novel”about a woman who lives in the dump of a U.S.Southwest desert town.The female character who“inhabits”the dump-and this poet’s novel-is both metonym for and guide into the lost representation of“the abject,”a concept developed by Julia Kristeva as a psychic state of horror and response to that which lies outside culturally“normalized”subjects and objects,and our“desire for meaning.”Utilizing her dump refuse for its materials,the main character,Marie,creates her own“culture of one,”standing as figure for the artist/writer plunging not“meaning”but meaninglessness and its abject association with death,which is prefigured as the unclean,the improper,rejected body parts,deviant“non-existent”personae-and,ultimately,Marie’s figural status as marginal inhabitant/“culture remaker”/older woman/multi-media“poet”artist.Without traditional conventions of novelistic character development,plot,and visual description,Notley’s“poet’s novel”formally engages in what Viktor Shkolvsky,in his well-known essay“Art as Technique,”terms“defamiliarization”or“strangeness”(“ostranenie,”in Russian),including those principles he cites of“deceleration”and“deviation of the norm.”Notley’s work twists the binary logic implied in Shkolvsky’s“deviation”versus“norm”further by revealing abjection’s“strangeness”in the poet’s novel itself as form,”a text that is always becoming its own site of the linguistic abject,never codifying identity,or the interpreted known.

关键词： Alice Notley the poet’s novel prose poem the abject Kristevan theory.

Sensitivity and specificity of hearing tests for screening hearing loss in older adults

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Journal of Otology 2023年第1期18卷 1-6页

作者： Hsin-Chen Ting Yung-Yao Huang PSA Charitable Foundation New Taipei CityTaiwanChina Department of Audiology and Speech-Language Pathology MacKay Medical CollegeNew Taipei CityTaiwanChina

Objectives: The study aimed to determine the most appropriate hearing screening test to identify disabling hearing loss for adults aged 65 years or older.Methods: This study included 577 older adults. Four hearing screening tests were considered in the study, including the Hearing Handicap Inventory for Elderly Screening(HHIE-s), three single question tests, the whisper test, and the finger rub test. The sensitivity and specificity of these tests referenced to the hearing threshold of disabling hearing loss were estimated.Results: Among all tests, only the single self-perception question(0.7064 for sensitivity;0.7225 for specificity) and whisper test(0.7833 for sensitivity;0.7708 for specificity) could obtain both sensitivity and specificity higher than 70% for adults aged ≥65 years.Conclusion: Overall, we suggest using the whisper test to identify disabling hearing loss(>40 dB HL at the better ear) for adults aged 65 years or older. However, if the conditions do not permit, the single selfperception question is also acceptable. Moreover, HHIE-s might not be a good test to detect disabling hearing loss for adults aged 80 years or older.

关键词： Sensitivity and specificity Hearing screening Questionnaire Whisper test Finger rub test

Self-Reported Hair Loss Following COVID-19: An Observational Study

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International Journal of Dermatology and Venereology 2023年第1期6卷 29-34页

作者： Abdulmajeed Alajlan Rema Aldihan Lyan Almana Rahaf Althnayan Hadeel Awartani Sami Alsuwaidan Department of Dermatology College of MedicineKing Saud UniversityMedical CityRiyadh 12372Saudi Arabia college of Medicine King Saud UniversityMedical CityRiyadh 12372Saudi Arabia

Objective: COVID-19 has been significantly associated with both psychosocial stress and physiologic stress, both of which are known to trigger telogen effluvium. This study was performed to estimate the prevalence of hair loss among patients with COVID-19 and to determine the correlation of the severity of COVID-19 with the severity of hair loss.Methods: Data were collected through a self-administered electronic questionnaire that was distributed among social media platforms. Participants were invited to complete the survey using a convenience sampling technique. A multiple response dichotomies analysis and chi-square test of independence were used to analyze data.Results: Among 420 participants who reported a positive PCR result of SARS-CoV-2, 77.6% reported hair loss after COVID-19 development. Notably, the onset of hair loss was within 3 weeks of COVID-19 development in 29% of participants. Most of the participants reported that the duration of hair loss was up to 6 months, and hair regrowth was noticed within 1 year after COVID-19 development. Patients who were admitted to the hospital, who experienced respiratory difficulties, who had lost weight due to COVID-19, and who experienced symptoms for longer than 10 days were significantly more prone to experience severe hair loss following COVID-19 (P < 0.001).Conclusion: This study demonstrated a high frequency of self-reported hair loss after the development of COVID-19. Interestingly, even patients with mild COVID-19 symptoms were significantly more prone to experience moderate hair loss. Unique to COVID-19 infection, the onset of hair loss following the development of COVID-19 was within 3 weeks in one-third of the participants.

关键词： telogen effluvium COVID-19 SARS-CoV-2 hair loss