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Oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions via Prufer transformation

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 191-200页

作者： LI Zhi-yu LI Kun CAI Jin-ming QIN jian-fang ZHENG Zhao-wen School of Mathematical Sciences Qufu Normal UniversityQufu 273165China College of Mathematics and Systems Science Guangdong Polytechnic Normal UniversityGuangzhou 510665China

A class of Sturm-Liouville problems with discontinuity is studied in this *** oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are *** main method used in this paper is based on Prufer transformation,which is different from the classical ***,we give two examples to verify our main results.

关键词： Sturm-Liouville problem interface condition oscillatory solution

Functional analysis of the novel mitochondrial tRNA^(Trp)and tRNA^(Ser(AGY))variants associated with type 2 diabetes mellitus

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World Journal of Diabetes 2024年第8期15卷 1753-1763页

作者： Yu ding Xue-Jiao Yu Qin-Xian Guo jian-Hang Leng Central Laboratory Hangzhou First People’s HospitalHangzhou 310006Zhejiang ProvinceChina Clinical Laboratory Quzhou People’s HospitalQuzhou 324000Zhejiang ProvinceChina

BACKGROUND Mutations in mitochondrial tRNA(mt-tRNA)genes that result in mitochondrial dysfunction play important roles in type 2 diabetes mellitus(T2DM).We previously reported a large Chinese pedigree with maternally inherited T2DM that harbors novel mt-tRNA^(Trp)A5514G and tRNA^(Ser(AGY))C12237T variants,however,the effects of these mt-tRNA variants on T2DM progression are largely *** To assess the potential pathogenicity of T2DM-associated m.A5514G and m.C12237T variants at genetic,molecular,and biochemical *** Cytoplasmic hybrid(cybrid)cells carrying both m.A5514G and m.C12237T variants,and healthy control cells without these mitochondrial DNA(mtDNA)variants were generated using trans-mitochondrial *** features,including mt-tRNA steady-state level,levels of adenosine triphosphate(ATP),mitochondrial membrane potential(MMP),reactive oxygen species(ROS),mtDNA copy number,nicotinamide adenine dinucleotide(NAD+)/NADH ratio,enzymatic activities of respiratory chain complexes(RCCs),8-hydroxy-deoxyguanine(8-OhdG),malondialdehyde(MDA),and superoxide dismutase(SOD)were examined in cell lines with and without these mt-tRNA *** Compared with control cells,the m.A5514G variant caused an approximately 35%reduction in the steady-state level of mt-tRNA^(Trp)(P<0.0001);however,the m.C12237T variant did not affect the mt-tRNA^(Ser(AGY))steady-state level(P=0.5849).Biochemical analysis revealed that cells with both m.A5514G and m.C12237T variants exhibited more severe mitochondrial dysfunctions and elevated oxidative stress than control cells:ATP,MMP,NAD+/NADH ratio,enzyme activities of RCCs and SOD levels were markedly decreased in mutant cells(P<0.05 for all measures).By contrast,the levels of ROS,8-OhdG and MDA were significantly increased(P<0.05 for all measures),but mtDNA copy number was not affected by m.A5514G and m.C12237T variants(P=0.5942).CONCLUSION The m.A5514G variant impaired mt-tRNA^(Trp)metabolism,which subsequent

关键词： Type 2 diabetes mellitus Mitochondrial tRNA genes Novel variants Oxidative stress Mitochondrial dysfunctions

Improving mathematical model of burden distribution and correcting chute angle to cope with fluctuation of stock line

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Journal of Iron and Steel Research International 2024年第2期31卷 342-356页

作者： jian-sheng Chen Wen-guo Liu Hao Guo Wang ding Qing-guo Xue Jing-song Wang Hai-bin Zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China MCC Capital Engineering&Research Incorporation Limited Beijing100176China Hunan Valin Xiangtan Iron and Steel Co. Ltd.Xiangtan411101HunanChina

Accurate evaluations of the burden distribution are of critical importance to stabilize the operation of blast *** mathematical model and discrete element method(DEM)are two attractive methods for predicting burden *** on DEM,the initial velocities of the pellet,sinter,and coke were calculated,and the velocity attenuations of the above three particles between the burden and the chute were *** initial velocity and velocity attenuation were applied to a mathematical model for improving the ***,based on the improved model,a scheme for rectifying the chute angles was proposed to address the fluctuation of the stock line and maintain a stable burden *** validity of the scheme was confirmed via a stable burden distribution under different stock *** mathematical model has been successfully applied to evaluate the online burden distribution and cope with the fluctuation of the stock line.

关键词： Burden distribution Mathematical model Discrete element method Velocity attenuation Stock line fluctuation

Downregulation of Serum PTEN Expression in Mercury-Exposed Population and PI3K/AKT Pathway-Induced Inflammation

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Biomedical and Environmental Sciences 2024年第4期37卷 354-366页

作者： MEI Peng ding En Min YIN Hao Yang ding Xue Xue WANG Huan WANG jian Feng HAN Lei ZHANG Heng Dong ZHU Bao Li School of Public Health Nanjing Medical UniversityNanjing 210000JiangsuChina Institute of Occupational Disease Prevention Jiangsu Province Center for Disease Prevention and ControlNanjing 21000JiangsuChina Suzhou Center for Disease Prevention and Control Suzhou 215004JiangsuChina Center for Global Health School of Public HealthNanjing Medical UniversityNanjing 210000JiangsuChina

Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological *** Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation. Hg-exposed cell models and PTEN lowexpression models were established in vitro using 293T cells. PTEN gene expression was assessed using qRT-PCR, and Western blotting was used to measure PTEN, AKT, and PI3K protein levels. IL-6 expression was determined by *** Combined findings from gene expression microarray analysis, bioinformatics, and population expansion validation indicated significant downregulation of the PTEN gene in the high-concentration Hg exposure group. In the Hg-exposed cell model(25 and 10 μmol/L), a significant decrease in PTEN expression was observed, accompanied by a significant increase in PI3K, AKT, and IL-6 ***, a low-expression cell model demonstrated that PTEN gene knockdown led to a significant decrease in PTEN protein expression and a substantial increase in PI3K, AKT, and IL-6 *** This is the first study to report that Hg exposure downregulates the PTEN gene, activates the PI3K/AKT regulatory pathway, and increases the expression of inflammatory factors, ultimately resulting in kidney inflammation.

关键词： PTEN Occupational mercury exposure Occupational health PI3K/AKT pathway 293T cell IL-6

Occurrence and prevention of incisional hernia following laparoscopic colorectal surgery

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 1973-1980页

作者： Xi-Wen Wu ding-Quan Yang ming-Wei Wang Yan Jiao The First Operating Room The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Gastrointestinal and Colorectal Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina Ministry of Health Key Laboratory of Radiobiology School of Public Health of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Hepatobiliary and Pancreatic Surgery General Surgery CenterThe First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

Among minimally invasive surgical procedures,colorectal surgery is associated with a notably higher incidence of incisional hernia(IH),ranging from 1.7% to 24.3%.This complication poses a significant burden on the healthcare system annually,necessitating urgent attention from *** a study published in the World Journal of Gastrointestinal Surgery,Fan et al compared the incidence of IH among 1614 patients who underwent laparoscopic colorectal surgery with different extraction site locations and evaluated the risk factors associated with its *** editorial analyzes the current risk factors for IH after laparoscopic colorectal surgery,emphasizing the impact of obesity,surgical site infection,and the choice of incision location on its ***,we summarize the currently available preventive measures for *** the low surgical repair rate and high recurrence rate associated with IH,prevention deserves greater research and attention compared to treatment.

关键词： Incisional hernia Laparoscopy Colorectal surgery Risk factor Prevention

Disposal of zinc extraction residues via iron ore sintering process:an innovative resource utilization

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Journal of Iron and Steel Research International 2024年第7期31卷 1636-1645页

作者： Chun-long Fan Cheng-yi ding Tao Yang Yun-fei Luo Yi-fan Wang Qian Li Hong-ming Long School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina Zhongye Changtian International Engineering Co. Ltd.Changsha 410205HunanChina Key Laboratory of Metallurgical Emission Reduction and Resources Recycling(Ministry of Education) Anhui University of TechnologyMa'anshan 243002AnhuiChina

Zinc extraction residue,a solid waste generated from the treatment of zinc-containing dust in rotary kilns,is commonly stockpiled in steel companies for extended *** poses significant disposal challenges and environmental pollution *** far,research on the treatment of zinc extraction residues has been slow,inadequate,and *** this gap,a novel approach was proposed to effectively treat the zinc extraction residue via the iron ore sintering *** was feasible to add 1 wt.%of zinc extraction residues to the sintering raw *** more adequate mineralization reaction resulted in higher yield and tumbler indexes,despite a slight decrease in sintering *** this may result in a slight decrease in sintering speed,the more complete mineralization reaction leads to improved sintering yield and tumbler ***,the addition of zinc extraction residues reduced the CO and NO_(x) concentrations in the sintering flue ***,the iron ore sintering process provided a viable solution for resource utilization and environmentally friendly treatment of zinc extraction residues.

关键词： Zinc extraction residue Iron ore sintering Co-processing Waste utilization Gas pollutant reduction

Solidification crack characteristics and sensitivity of peritectic steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1668-1679页

作者： Ya-qiang Li jian-hua Liu Zi-ming Wang Ying-ying Li Yang He Xiao-wei Li Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Hebei Special Vehicle Modification Technology Innovation Center Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou 213164JiangsuChina

The characteristics and sensitivity of solidification cracks in peritectic steels were investigated using directional solidifi-cation *** cracks were observed in both hypoperitectic steels(12CrlMoV,15CrMo)and hyper-peritectic steel(20CrMo)during solidification at growth velocities of 15,50,and 80 pm/*** the dendritic boundaries,sulphide precipitates were found,promoting crack *** on the statistical analysis of interdendritic cracks in peritectic steels,the area ratio(RA)of interdendritic cracks in a directional solidification structure was proposed to evaluate the crack sensitivity of peritectic ***,the crack sensitivities of peritectic steels(12CrlMoV,15CrMo,and 20CrMo)were tested,evaluated,and compared with the surface crack rates of three types of steels produced from a steel *** results demonstrated that RA was in good agreement with that of the steel plant,and the crack sensitivity of 12CrlMoV steel was the strongest,followed by that of 15CrMo and 20CrMo ***,RA can be used to evaluate the crack sensitivity of peritectic steel.

关键词： Peritectic steel-Directional solidification Growth velocity Dendritic structure Solidification crack Crack sensitivity

Prevalence of vegetation browning in China’s drylands under climate change

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Geography and Sustainability 2024年第3期5卷 405-414页

作者： Li Fu Guolong Zhang jianping Huang ming Peng Lei ding Dongliang Han Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China

Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even ***,detailed analyses about greening reversal or increased browning of vegetation remain *** this study,we utilized the normalized difference vegetation index(NDVI)as an indicator of vegetation to investigate the trends of vegetation greening and browning(monotonic,interruption,and reversal)through the breaks for the additive season and trend(BFAST)method across China’s drylands from 1982 to *** also reveals the impacts of ecological restoration programs(ERPs)and climate change on these vegetation *** find that the vegetation displays an obvious pattern of east-greening and west-browning in China’s *** trends mainly exhibits monotonic greening(29.8%)and greening with setback(36.8%),whereas browning shows a greening to browning reversal(19.2%).The increase rate of greening to browning reversal is 0.0342/yr,which is apparently greater than that of greening with setback,0.0078/*** research highlights that,under the background of widespread vegetation greening,vegetation browning is pro-gressively increasing due to the effects of climate ***,the ERPs have significantly increased vegetation coverage,with the increase rate in 2000-2022 being twice as much as that of 1982-1999 in reveg-etation *** browning in southwestern Qingzang Plateau is primarily driven by adverse climatic factors and anthropogenic disturbances,which offset the efforts of ERPs.

关键词： China’s drylands Ecological restoration programs Climate change Greening to browning reversal BFAST

Male reproductive function before and after the adjustment of the COVID-19 prevention policy:a multicenter study in China

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Asian Journal of Andrology 2024年第3期26卷 308-314页

作者： jian-Zheng Li Han Wu Li Wang Yun-Shan Wang Feng Kong Long-Qiao Cao ming Liang Xiong Wang ming-Zhen Yuan Shandong Provincial Hospital Affiliated to Shandong First Medical University Jinan 250000China Institute of Women Children and Reproductive HealthShandong UniversityJinan 250012China Engineering Laboratory of Urinary Organ and Functional Reconstruction of Shandong Province Jinan 250000China The First People’sHospital of Jining Jining 272000China Department of Reproductive Medicine The Second Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan 250000China Reproductive Medicine Center Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantai 264000China

At the end of 2022,the adjustment of the coronavirus disease 2019(COVID-19)pandemic control policy in China resulted in alarge-scale increase in public *** compare the fertility parameters of male patients before and after the adjustments ofthe COVID-19 pandemic control policy in China,we collected data on patients’medical histories and laboratory examinations ontheir first visits between June 2022 and March 2023 in five different *** were divided into five groups according tothe timeline of the policy *** data we collected from male patients included semen quality and serum reproductivehormone levels,and intergroup comparisons were made using the Mann–Whitney U and Chi-square *** total,16784 casesunderwent regular semen analysis,11180 had sperm morphology assessments,and 7200 had reproductive hormone *** showed declining trends in semen volume,sperm motility,and the progressive sperm motility rate after the policy *** comparison revealed an initial decrease and gradual recovery in progressive motility *** morphology analysisshowed increased neck and tail abnormalities after the policy *** significant change in hormone levels was *** the adjustment of the COVID-19 prevention policy in China,a decline in sperm motility and morphology was *** trend may gradually recover over 2 *** the policy adjustment,reproductive hormone levels were relatively stablethroughout,except for an increase in luteinizing hormone(LH).These changes in semen parameters suggest that the policyadjustment had a short-to medium-term impact on male reproductive function.

关键词： COVID-19 multicenter study reproduction SARS-CoV-2 semen analysis