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H/V Spectral Ratio Reveals Seismic Response of Base-Isolated Large-Span High-Rise in Beijing
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作者 Zhangdi Xie Cantao Zhuang +2 位作者 Yong Wu Linghui Niu Jianming Zhao 《Structural Durability & Health Monitoring》 2026年第1期341-354,共14页
This study employed tri-component continuous monitoring data from 10 measurement points on both sides of a base isolation layer in the basement of a large-span high-rise building in Beijing,as well as from a free-fiel... This study employed tri-component continuous monitoring data from 10 measurement points on both sides of a base isolation layer in the basement of a large-span high-rise building in Beijing,as well as from a free-field station and roof frame,during a Mw 5.5 magnitude earthquake in Pingyuan,Shandong,in 2023.The H/V spectral ratio method was used to evaluate the structural dynamic response characteristics of the building and analyze the regulatory effect of the base-isolation layer on seismic waves.The results indicate that during the earthquake,the peak frequency of the free-field and the measurement points below the base-isolation layer was stable at 0.17 Hz,whereas the main frequency of the measurement points above the base-isolation layer increased to 0.75–1.18 Hz,which is 4–6 times greater than that of the points below.The amplitude was suppressed by more than 70%,confirming that the base isolation layer effectively isolated the low-frequency energy from the ground and increased the response frequency of the building.When the building was excited by an earthquake,a three-tier frequency gradient was formed throughout the building:“base-isolation layer(0.17 Hz)-main body(1.18 Hz)-roof frame(3.83 Hz)”,which can effectively avoid resonance of the entire building.In addition,the composite base-isolation device changed the dynamic characteristics of the structure.The resonance period was extended from 0.74 s(theoretical value without base isolation)to 5.9 s(calculated value),and the resonance frequency was reduced from 1.35 to 0.17 Hz.This finding indicates that the base-isolation layer can enhance seismic performance by increasing flexibility and damping. 展开更多
关键词 H/V spectral ratio method seismic isolation system seismic response characteristics three-stage frequency gradient energy dissipation mechanism
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Isolated Systolic Hypertension in Geriatrics
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作者 Soumya Erri Terry Oroszi 《International Journal of Clinical Medicine》 2025年第1期29-53,共25页
Hypertension, often called the “silent killer”, is a major risk factor for heart attacks and strokes in the elderly. Its effective management is crucial to prevent damage to the heart, brain, and kidneys. Isolated s... Hypertension, often called the “silent killer”, is a major risk factor for heart attacks and strokes in the elderly. Its effective management is crucial to prevent damage to the heart, brain, and kidneys. Isolated systolic hypertension (ISH) is particularly critical in the elderly population. Cardiovascular risk factors, including pulse pressure and wave velocity, are closely associated with systolic blood pressure and influenced by arterial stiffness and wave reflections. Managing ISH is complex due to the potential negative effects of certain medications and individual variability in treatment response. This paper will address these issues, evaluating antihypertensive drugs, combination therapy, personalized treatment plans, and updated guidelines for managing ISH. 展开更多
关键词 HYPERTENSION Geriatric or Elderly or Adults Types of Hypertension Tests First-Line Treatment DRUGS isolated Systolic Hypertension Other Diseases
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Trends and emerging techniques in isolated power converters
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作者 Lin Cheng Dongfang Pan 《Journal of Semiconductors》 2025年第7期6-9,共4页
Isolated power converters have emerged as an active research topic in power integrated circuit(IC)design.Reflecting this growing interest,ISSCC 2025 has featured a dedicated session on"Isolated Power and Gate Dri... Isolated power converters have emerged as an active research topic in power integrated circuit(IC)design.Reflecting this growing interest,ISSCC 2025 has featured a dedicated session on"Isolated Power and Gate Drivers".These converters enable safe and reliable power delivery across voltage domains and are widely used in renewable energy,electric vehicles,and telecommunications.Galvanic isolation prevents surge currents and ground loop issues in harsh high-voltage environments.As demand grows for compact,efficient,and high–power-density solutions,fully integrated architectures featuring on-chip transformers are increasingly favored over traditional module-based designs,offering>5 kV isolation with a smaller footprint and lower system cost[1]. 展开更多
关键词 ISSCC ground loop issues isolated power converters power integrated circuit galvanic isolation emerging techniques surge currents renewable energyelectric
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Role of varicocelectomy in infertile patients with clinical varicocele and isolated sperm defects
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作者 Mohamed M.Arafa Ahmad A.Majzoub +6 位作者 Walid A.El Ansari Ahmad H.AlMalki Mohammed Y.Mahdi Kareim M.Khalafalla Khalid J.AlKubaisi Sami S.AlSaid Haitham T.ElBardisi 《Asian Journal of Urology》 2025年第2期267-274,共8页
Objective:This study investigated the outcomes of microsurgical subinguinal varicocelectomy(MSV)on semen and hormonal parameters in cases with isolated sperm defects(oligozoospermia,asthenozoospermia,or teratozoosperm... Objective:This study investigated the outcomes of microsurgical subinguinal varicocelectomy(MSV)on semen and hormonal parameters in cases with isolated sperm defects(oligozoospermia,asthenozoospermia,or teratozoospermia).Methods:A retrospective review of charts of patients who underwent MSV for clinically palpable varicocele between January 1,2011 and January 1,2019 at Hamad Medical Corporation was undertaken.All patients diagnosed with isolated oligozoospermia,asthenozoospermia,or teratozoospermia in the preoperative semen analysis were included.Men with multiple sperm defects,genetic abnormalities,azoospermia,history of genitourinary infection,exposure to chemotherapy or radiotherapy,or prior use of peri-operative fertility treatment were excluded.Data extracted from the electronic medical records included(collected before MSV and up to 6 months postoperatively):demographics(age),clinical data(fertility-related medical history and surgical interventions),family history(consanguinity and infertility),physical examination findings from general and local genital exam(varicocele side and grade),laboratory data such as semen analysis,sperm DNA fragmentation tests,and hormone levels(follicle-stimulating hormone,luteinizing hormone,total testosterone,estradiol,and prolactin),and imaging(scrotal color Doppler ultrasound).Results:A total of 331 patients with isolated sperm defects were included.Postoperatively,83.3%of patients showed an improvement in sperm concentration with a median increase of 7 millions/mL.Postoperatively,76.7%of isolated asthenozoospermic patients showed an improvement in total motility and 66.0%had an improvement in progressive motility with median increases of 15.0%and 7.5%,respectively.Postoperatively,70.0%of the teratozoospermic patients showed an improvement in normal sperm morphology with a median increase of 6%.No changes were observed in other semen or hormone parameters that were examined.Conclusion:MSV is a valid and effective treatment modality for patients with isolated sperm defects that significantly corrects their respective semen abnormality and improves their chances of natural conception. 展开更多
关键词 VARICOCELECTOMY isolateD OLIGOZOOSPERMIA ASTHENOZOOSPERMIA TERATOZOOSPERMIA Fertility
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Influence of isolated footing embedment on the seismic performance of building considering the soil-foundation-structure interaction:An experimental approach
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作者 Vaibhav Mittal Manojit Samanta D.P.Kanungo 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期1194-1212,共19页
The present study investigates the influence of embedment depth of isolated footing supporting moment-resisting frame buildings through scaled-down tests.These experiments utilize scaled models representing different ... The present study investigates the influence of embedment depth of isolated footing supporting moment-resisting frame buildings through scaled-down tests.These experiments utilize scaled models representing different building aspect ratios and footing embedment depths.All the model tests are subjected to scaled-down input ground motions of different intensities and magnitudes.These model tests are performed in laminar shear containers through shake table testing.The results obtained for different cases of soil-foundation-structure systems and fixed-base conditions are expressed in terms of natural frequency,peak spectral acceleration,frequency response,lateral deformation,inter-storey drifts,and rocking of the foundation.The analysis reveals that the natural frequency of the coupled system on isolated footings diminishes by 27.52%–58.21%relative to fixed-base conditions,highlighting the significance of accounting for soil-foundation-structure interaction effects.Moreover,a notable increase of 52.97%in the natural frequency of the coupled system is observed as the embedment depth of the footing increases from 0.75 to 6.Additionally,the study demonstrates that the inter-storey drift of the 5-storey building remains well within acceptable limits under dense soil conditions.Consequently,within the parameter range explored in this research,the study concludes that soil-foundation-structure interaction effects are insignificant for low-rise buildings(H≤15 m)supported on isolated footings during seismic events. 展开更多
关键词 Shake table test isolated footing Soil-foundation-structure interaction Laminar shear box EARTHQUAKE
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Multi-objective optimal design of asymmetric base-isolated structures using NSGA-Ⅱ algorithm for improving torsional resistance
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作者 Zhang Jiayu Qi Ai Yang Mianyue 《Earthquake Engineering and Engineering Vibration》 2025年第3期811-825,共15页
Finding an optimal isolator arrangement for asymmetric structures using traditional conceptual design methods that can significantly minimize torsional response while ensuring efficient horizontal seismic isolation is... Finding an optimal isolator arrangement for asymmetric structures using traditional conceptual design methods that can significantly minimize torsional response while ensuring efficient horizontal seismic isolation is cumbersome and inefficient.Thus,this work develops a multi-objective optimization method to enhance the torsional resistance of asymmetric base-isolated structures.The primary objective is to simultaneously minimize the interstory rotation of the superstructure,the rotation of the isolation layer,and the interstory displacement of the superstructure without exceeding the isolator displacement limits.A fast non-dominated sorting genetic algorithm(NSGA-Ⅱ)is employed to satisfy this optimization objective.Subsequently,the isolator arrangement,encompassing both positions and categories,is optimized according to this multi-objective optimization method.Additionally,an optimization design platform is developed to streamline the design operation.This platform integrates the input of optimization parameters,the output of optimization results,the finite element analysis,and the multi-objective optimization method proposed herein.Finally,the application of this multi-objective optimization method and its associated platform are demonstrated on two asymmetric base-isolated structures of varying heights and plan configurations.The results indicate that the optimal isolator arrangement derived from the optimization method can further improve the control over the lateral and torsional responses of asymmetric base-isolated structures compared to conventional conceptual design methods.Notably,the interstory rotation of the optimal base-isolated structure is significantly reduced,constituting only approximately 33.7%of that observed in the original base-isolated structure.The proposed platform facilitates the automatic generation of the optimal design scheme for the isolators of asymmetric base-isolated structures,offering valuable insights and guidance for the burgeoning field of intelligent civil engineering design. 展开更多
关键词 asymmetric base-isolated structures isolator arrangement multi-objective optimization NSGA-Ⅱalgorithm optimization design platform
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Establishment of goat infection model of the peste des petits ruminants virus isolated in China for vaccine efficacy evaluation
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作者 Xue Wang Hefeng Chen +14 位作者 Xianfeng Zhang Zhengshuang Wu Shuai Zhang Lei Shuai Lulu Wang Weijie Li Jinliang Wang Wenxing Liu Xijun Wang Zhiyuan Wen Jinying Ge Yuntao Guan Xijun He Weiye Chen Zhigao Bu 《Journal of Integrative Agriculture》 2025年第8期3199-3211,共13页
In 2013,peste des petits ruminants(PPR)re-emerged in China and spread to the majority of provinces across the country.The disease was effectively controlled through a vaccination campaign employing live attenuated vac... In 2013,peste des petits ruminants(PPR)re-emerged in China and spread to the majority of provinces across the country.The disease was effectively controlled through a vaccination campaign employing live attenuated vaccines,although sporadic cases still occurred.However,limited information is currently available regarding the peste des petits ruminants virus(PPRV)endemic in China.Here,a PPRV strain(HLJ/13)was isolated from a field sample in China using Vero cells expressing goat signalling lymphocyte activation molecule.Phylogenetic analysis indicated that HLJ/13 belonged to lineage IV.Subsequent intranasal and subcutaneous inoculation of goats with a dose of 2×10~6 TCID50of HLJ/13 resulted in the development of typical clinical symptoms of PPR,including pyrexia,ocular and nasal discharges,stomatitis,and diarrhea.All infected goats succumbed to the disease by day 8.To gain further insight,viral loading,pathological examination and immunohistochemical analyses were conducted,elucidating the main targets of HLJ/13 as the respiratory system,digestive tract and lymphoid organs.Employing the goat infection model established above,the goat poxvirus-vectored PPR vaccine,which was previously developed and could be used as DIVA(differentiating infected from vaccinated animals)vaccine,provided complete protection against the challenge of HLJ/13.It is important to note that this study represents the first comprehensive report delineating the biology and pathogenicity characterization,and infection model of PPRV isolated in China. 展开更多
关键词 peste des petits ruminants virus Chinese isolate goat infection model vaccine efficacy evaluation
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Effectiveness of biologics for endoscopic healing in patients with isolated proximal small bowel Crohn’s disease
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作者 Zi-Cheng Huang Bi-Yao Wang +8 位作者 Bo Peng Zhong-Cheng Liu Hui-Xian Lin Qing-Fan Yang Jian Tang Kang Chao Miao Li Xiang Gao Qin Guo 《World Journal of Gastroenterology》 2025年第7期39-50,共12页
BACKGROUND Endoscopic healing(EH)is a key therapeutic target in Crohn’s disease(CD).Proximal small bowel(SB)lesions in patients with CD are associated with a significant risk of strictures and bowel resection.Assessi... BACKGROUND Endoscopic healing(EH)is a key therapeutic target in Crohn’s disease(CD).Proximal small bowel(SB)lesions in patients with CD are associated with a significant risk of strictures and bowel resection.Assessing SB in patients with CD is necessary because of its significant therapeutic implications.The advent of biologic therapies,including infliximab,ustekinumab,and vedolizumab,has significantly altered CD treatment.However,data on the efficacy of biologics in achieving EH,specifically in the proximal SB of patients with CD,remain limited.AIM To assess the effectiveness of biologics for EH in patients with jejunal and/or proximal ileal CD.METHODS Between 2017 and 2023,we retrospectively included 110 consecutive patients with isolated proximal SB CD,identified through baseline balloon-assisted enteroscopy.These patients completed 1-year of treatment with infliximab,ustekinumab,or vedolizumab,and underwent a second balloon-assisted enteroscopy at 1 year.Complete EH was defined as a modified Simple Endoscopic Score for CD(SES-CD)of<3,while EH of the jejunum and proximal ileum was defined as a segmental modified SES-CD of 0.RESULTS In total,64 patients were treated with infliximab,28 with ustekinumab,and 18 with vedolizumab.The complete EH rate at 1 year was 20.9%(23/110),with 29.6%(19/64)for infliximab,10.7%(3/28)for ustekinumab,and 5.5%(1/18)for vedolizumab.The median modified SES-CD significantly decreased compared to baseline[5(2-8)vs 8(6-9),P<0.001].The jejunal and proximal ileal EH rates at 1 year were 30.8%(12/39)and 15.5%(16/103),respectively.Multiple logistic regression analysis showed that stricturing or penetrating disease[odds ratio(OR)=0.261,95%CI:0.087-0.778,P=0.016],prior exposure to biologics(OR=0.080,95%CI:0.010-0.674,P=0.020),and moderate-tosevere endoscopic disease(OR=0.277,95%CI:0.093-0.829,P=0.022)were associated with a lower likelihood of achieving EH at 1 year.CONCLUSION Only 20.9%of patients with isolated proximal SB CD achieved complete EH after 1 year of biologic therapy. 展开更多
关键词 Crohn’s disease isolated proximal small bowel disease Endoscopic healing BIOLOGICS Balloon-assisted enteroscopy
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Sequence stratigraphy analysis and lithofacies paleogeography reconstruction of isolated platform in a rift lake basin:Implications for deepwater hydrocarbon exploration in the subsalt of Santos Basin,Brazil
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作者 HUANG Jixin WANG Hongjun +7 位作者 XU Fang YANG Mengying ZHAO Junfeng LI Peijia LI Chenqing LIU Zeqiang XIONG Ying TAN Xiucheng 《Petroleum Exploration and Development》 2025年第4期982-1000,共19页
By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pat... By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pattern of fault-bounded isolated platforms in rift lake basins,reveal the control mechanisms of shoal-body development and reservoir formation,and reconstruct the evolutionary history of lithofacies paleogeography.The following results are obtained.(1)Three tertiary sequences(SQ1-SQ3)are identified in the Lower Cretaceous Itapema-Barra Velha of the M block.During the depositional period of SQ1,the rift basement faults controlled the stratigraphic distribution pattern of thick on both sides and thin in the middle.The strata overlapped to uplift in the early stage.During the depositional period of SQ2-SQ3,the synsedimentary faults controlled the paleogeomorphic reworking process with subsidence in the northwest and uplifting in the northeast,accompanied with the relative fall of lake level.(2)The Lower Cretaceous in the M block was deposited in a littoral-shallow lake,with the lithofacies paleogeographic pattern transiting from the inner clastic shoals and outer shelly shoals in SQ1 to the alternation of mounds and shoals in SQ2-SQ3.(3)Under the joint control of relative lake-level fluctuation,synsedimentary faults and volcanic activity,the shelly shoals in SQ1 tend to accumulated vertically in the raised area,and the mound-shoal complex in SQ2-SQ3 tends to migrate laterally towards the slope-break belt due to the reduction of accommodation space.(4)The evolution pattern of high-energy mounds and shoals,which were vertically accumulated in the early stage and laterally migrated in the later stage,controlled the transformation of high-quality reservoirs from“centralized”to“ring shaped”distribution.The research findings clarify the sedimentary patterns of mounds and shoals and the distribution of favorable reservoirs in the fault-controlled lacustrine isolated platform,providing support for the deepwater hydrocarbon exploration in the subsalt carbonate rocks in the Santos Basin. 展开更多
关键词 lacustrine carbonate fault-bounded isolated platform sedimentary pattern sequence lithofacies paleogeography Cretaceous Itapema-Barra Velha Santos Basin
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Environmentally Friendly Tannic Acid-Furfuryl Alcohol-Soybean Isolate/Casein Composite Foams Reinforced with Wood Fibers
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作者 Jinxing Li Mustafa Zor +3 位作者 Xiaojian Zhou Guanben Du Denis Rodrigue Xiaodong(Alice)Wang 《Journal of Renewable Materials》 2025年第2期329-347,共19页
In this study,two series of foams based on tannic acid(TA),furfuryl alcohol(FA),soybean protein isolate(SPI),and casein(CA),namely TA–FA–SPI(TS series)and TA–FA–CA(TC series)were developed,and their properties wer... In this study,two series of foams based on tannic acid(TA),furfuryl alcohol(FA),soybean protein isolate(SPI),and casein(CA),namely TA–FA–SPI(TS series)and TA–FA–CA(TC series)were developed,and their properties were enhanced by adding poplar fibers(WF).From the samples produced,a complete set of characterization was performed including possible crosslinking reactions,morphology,mechanical properties,flame retardancy,thermal insulation and thermal stability.Fourier-transform infrared spectroscopy(FTIR)revealed possible covalent crosslinking among the components and hydrogen bonding between WF and the matrix.Viscosity results indicated that lower prepolymer viscosity led to lower apparent density,while WF addition reduced even more the density.Mechanical tests showed that the maximum compressive strengths were good,while WF improved the compressive strength by up to 56%.Scanning electron microscopy(SEM)showed uniform cell structures,but small open pores were observed.Two-dimensional(2D)CT scan images confirmed the good compatibility between WF and the matrix,with low anisotropy in the material.Friability tests indicated that WF decreased the pulverization ratio of the materials by up to 42%.Thermogravimetric analysis(TGA)showed good thermal stability of the materials up to 328°C.Vertical burning tests showed that the materials were self-extinguishing without residue(dripping).The lowest thermal conductivity was 0.04 W/m·K.These results suggest that these novel formaldehyde-free,high biomass content(95%–96%)foams and composite foams have high potential to replace traditional phenolic foams(PF)in applications such as construction,transportation,packaging,and thermal insulation. 展开更多
关键词 Foam composite tannic acid soybean isolate protein CASEIN poplar fiber compressive strength flame retardancy thermal insulation
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Comparative analysis between genotypes of adenovirus isolates from hospitalized children with acute respiratory tract infections and clinical manifestations in Wuhan,China,from June 2022 to September 2023
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作者 Chunchen Wu Yanfang Zhang +9 位作者 Ao Liang Xiaoxue Wu Yaqi Zhu Zhaoxuan Huang Jun Wang Yali Deng Lixian Pan Anbang Wang Fei Deng Jianbo Xia 《Virologica Sinica》 2025年第1期50-60,共11页
Acute respiratory tract infections(ARTIs)are among the leading causes of morbidity and mortality in children worldwide.Human adenovirus(HAdV)infections are estimated to account for at least 5%of pediatric ARTIs.The ci... Acute respiratory tract infections(ARTIs)are among the leading causes of morbidity and mortality in children worldwide.Human adenovirus(HAdV)infections are estimated to account for at least 5%of pediatric ARTIs.The circulated genotypes of HAdV and the correlation between genotype and clinical manifestations in Wuhan,China,before and after the complete relaxation of nonpharmaceutical interventions against severe acute respiratory syndrome coronavirus 2,remain unknown.Here,101 HAdV strains were isolated from throat swab samples collected from hospitalized children with ARTIs who tested positive for HAdV nucleic acid.Of these,sixty-six strains from 2022 to twenty-three strains from 2023 were successfully genotyped and subjected to phylogenetic analysis based on the hexon,penton base,and fiber genes.Six genotypes,B3,C1,C2,C5,C104,and C108 were identified.HAdV-B3(84.85%)was the most prevalent type in 2022,while HAdV-C(86.96%),including C1,C2,C108,and C104,was the most prevalent in 2023.These strains were phylogenetically related to strains from Japan,China,and the United States in recent years.When comparing clinical characteristics,pediatric patients infected with B3,C1,C2,C5,C104,or C108 exhibited similar clinical manifestations,primarily fever and cough,but varying interleukin(IL)-10 levels.In conclusion,from June 2022 to September 2023,the circulated genotypes of HAdV in Wuhan included B3,C1,C2,C108,C5,and C104.The endemic pattern of HAdV in Wuhan,China,shifted from species B as the dominant type in 2022 to species C in 2023. 展开更多
关键词 Acute respiratory tract infection (ARTIs) Human adenovirus(HAdV) Viral isolates GENOTYPES Clinical characteristics PNEUMONIA
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Transcatheter aortic valve replacement for older patients with isolated aortic regurgitation
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作者 JoséC González Ignacio J.Amat 《Journal of Geriatric Cardiology》 2025年第7期611-614,共4页
Aortic regurgitation(AR)poses distinct challenges in interventional cardiology,necessitating novel approaches for treatment.This editorial examined the evolving landscape of transcatheter aortic valve replacement(TAVR... Aortic regurgitation(AR)poses distinct challenges in interventional cardiology,necessitating novel approaches for treatment.This editorial examined the evolving landscape of transcatheter aortic valve replacement(TAVR)as an alternative therapeutic strategy for AR,particularly in patients deemed high risk for surgery.We explored the anatomical and patho-physiological disparities between AR and aortic stenosis(AS)and elucidates the technical nuances of TAVR procedures in AR pa-tients,emphasizing the need for precise prosthesis positioning and considerations for excessive stroke volume.Additionally,we discussed the safety and efficacy of TAVR compared to SAVR in AR management,drawing insights from recent case series and registry data.Notably,dedicated TAVR devices tailored for AR,such as the J-Valve and JenaValve,demonstrate promising out-comes in reducing residual AR and ensuring procedural success.Conversely,“off-label”TAVR devices,including balloon-ex-pandable and self-expandable platforms,offer feasible alternatives-particularly for large aortic annuli-with favorable device suc-cess rates and low residual AR rates.We highlighted the need for further research,including randomized trials,to delineate the definitive role of TAVR in AR treatment and to address remaining questions regarding device selection and long-term outcomes.In conclusion,TAVR emerges as a viable option for patients with AR,particularly those facing high surgical risks or frailty,with ongoing investigations poised to refine its position in the therapeutic armamentarium. 展开更多
关键词 aortic regurgitation ar poses prosthesis positioning therapeutic strategy isolated aortic regurgitation transcatheter aortic valve replacement transcatheter aortic valve replacement tavr technical nuances residual aortic regurgitation
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全户内变电站装配式钢框架部分隔震结构体系振动台试验
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作者 郭小农 陈劭臻 +2 位作者 罗金辉 方瑜 吴祖咸 《同济大学学报(自然科学版)》 北大核心 2026年第2期182-191,263,共11页
针对既有非隔震全户内变电站中楼面设备加速度超限的问题,提出在楼板与设备之间增设隔震支座的部分隔震改造策略。基于此,设计并开展了全户内变电站装配式钢框架结构的振动台试验,包括基底固定体系(FBS)、基底隔震体系(BIS)以及部分隔... 针对既有非隔震全户内变电站中楼面设备加速度超限的问题,提出在楼板与设备之间增设隔震支座的部分隔震改造策略。基于此,设计并开展了全户内变电站装配式钢框架结构的振动台试验,包括基底固定体系(FBS)、基底隔震体系(BIS)以及部分隔震体系(PIS)。其中,根据所采用隔震支座的类型,BIS又分为天然橡胶支座(BIS-LNR)和铅芯橡胶支座(BIS-LR)2种型式。试验结果表明,FBS的最大设备加速度达到1.42g,远超限值0.6g,而BIS-LNR、BIS-LR和PIS分别将设备加速度平均降低了87%、69%和77%。在结构响应方面,BIS的最大层间位移角仅为FBS的38%;PIS与FBS相近,两者最大层间位移角均远小于限值1/50。因此,将既有非隔震全户内变电站改造为PIS,能实现结构与设备响应的双重控制目标。 展开更多
关键词 部分隔震 基底隔震 钢框架结构 振动台试验
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猪血凝性脑脊髓炎病毒河南株的分离鉴定
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作者 郭爽 康静静 +4 位作者 罗琴 于瑞 樊明明 李秀青 吴玉臣 《畜牧与兽医》 北大核心 2026年第3期75-81,共7页
为了明确河南地区猪场中猪凝性脑脊髓炎病毒(porcine hemagglutinating encephalomyelitis virus,PHEV)流毒株的物学特性,采集河南省信阳市某猪场的患病仔猪样本,进行病毒分离、细胞培养,电镜检测、病毒半数感染剂量(TCID50)测定、动物... 为了明确河南地区猪场中猪凝性脑脊髓炎病毒(porcine hemagglutinating encephalomyelitis virus,PHEV)流毒株的物学特性,采集河南省信阳市某猪场的患病仔猪样本,进行病毒分离、细胞培养,电镜检测、病毒半数感染剂量(TCID50)测定、动物试验以及病毒M、N基因的扩增和序列分析。结果:将分离获得的病毒接种于PK-15细胞后,可诱导明显的细胞病变效应,电镜负染可观察到星状近似球形的病毒粒子,并呈现典型帽子结构;攻毒后小鼠表现神经症状,脑组织病理学检查呈现病毒性脑炎特征,病变组织经PCR鉴定后,出现与PHEV目标片段大小一致的条带;N、M基因遗传进化树分析显示与JT06-China以及比利时的PHEV-VW572亲缘关系较近,属于流行毒株,未见明显变异。本研究结果可为河南猪场猪血凝性脑脊髓炎的防控提供理论依据。 展开更多
关键词 河南 猪血凝性脑脊髓炎病毒 病毒分离 变异毒株
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云南地区血清7型猪胸膜肺炎放线杆菌的分离鉴定及生物学特性分析
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作者 李富祥 宋建领 李占鸿 《中国畜牧兽医》 北大核心 2026年第1期499-508,共10页
【目的】研究云南地区猪源胸膜肺炎放线杆菌的生物学特性。【方法】从云南红河州某猪场患呼吸道疾病猪肺脏中分离细菌,采用生化试验、16S rDNA序列分析和PCR扩增鉴定分离菌,并分析分离菌的血清型、致病性、药物敏感性和耐药基因等生物... 【目的】研究云南地区猪源胸膜肺炎放线杆菌的生物学特性。【方法】从云南红河州某猪场患呼吸道疾病猪肺脏中分离细菌,采用生化试验、16S rDNA序列分析和PCR扩增鉴定分离菌,并分析分离菌的血清型、致病性、药物敏感性和耐药基因等生物学特性。【结果】从病猪肺脏样品中分离到1株革兰阴性小球杆菌,将其编号为YN240724。生化鉴定结果显示,分离菌分解葡萄糖、果糖、蔗糖、木糖和甘露醇产酸,氧化酶、尿素酶及硝酸盐还原试验呈阳性,其生化特性与胸膜肺炎放线杆菌(Actinobacillus pleuropneumoniae)参考株相同。16S rDNA基因序列分析结果显示,分离菌与胸膜肺炎放线杆菌模式菌株ATCC 27088T和其他胸膜肺炎放线杆菌参考株间的16S rDNA序列相似性分别为100%和99.6%~100%;分离菌株与全部胸膜肺炎放线杆菌参考株形成同一个进化分支;基于上述特征分离菌YN24074被鉴定为胸膜肺炎放线杆菌。血清型鉴定结果显示,该分离菌为胸膜肺炎放线杆菌血清7型。耐药基因检测结果显示,分离菌携带β-内酰胺内耐药基因blaCIT和blaTEM以及四环素类耐药基因tetM。药敏试验结果显示,分离菌对氨基糖苷类(庆大霉素和阿米卡星)、喹诺酮类(氧氟沙星)、酰胺醇类(氟苯尼考)、四环素类(四环素)、磺胺类(磺胺甲噁唑)以及头孢类(头孢噻肟和头孢呋辛)敏感,对青霉素类(青霉素、氨苄西林和哌拉西林)以及糖肽类(万古霉素)耐药。致病性试验结果显示,分离菌对小鼠的半数致死量(LD_(50))为7.5×10^(4)CFU,致病性较强。【结论】本研究从云南地区分离获得1株猪源血清7型胸膜肺炎放线杆菌,其携带耐药基因blaCIT、blaTEM及tetM,对多种抗菌药物表现耐药,致病性较强。试验结果可为云南地区猪场猪传染性胸膜肺炎的治疗和免疫防控提供重要参考。 展开更多
关键词 胸膜肺炎放线杆菌 分离鉴定 血清型 致病性
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新疆地区奶牛乳腺炎肺炎克雷伯菌的分离鉴定与耐药性分析
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作者 蔡扩军 徐敏 +2 位作者 孙鹏亮 夏利宁 赵红琼 《畜牧兽医学报》 北大核心 2026年第1期464-475,共12页
旨在了解新疆地区奶牛乳腺炎肺炎克雷伯菌的流行情况与耐药特性。本研究从新疆奶牛集约化养殖集中的9个地区采集15个规模奶牛养殖场奶牛2083份临床乳腺炎和隐性乳腺炎奶样,对样品中的肺炎克雷伯菌进行分离培养、革兰染色,并采用PCR及16S... 旨在了解新疆地区奶牛乳腺炎肺炎克雷伯菌的流行情况与耐药特性。本研究从新疆奶牛集约化养殖集中的9个地区采集15个规模奶牛养殖场奶牛2083份临床乳腺炎和隐性乳腺炎奶样,对样品中的肺炎克雷伯菌进行分离培养、革兰染色,并采用PCR及16S rRNA测序进行鉴定,对分离菌株采用微量肉汤稀释法检测耐药情况。结果表明,从奶样中分离出266株肺炎克雷伯菌,分离率为12.8%(266/2083),临床乳腺炎和隐性乳腺炎奶样肺炎克雷伯菌分离率无显著差异(P>0.05)。采用微量肉汤稀释法测定266个分离株对16种抗菌药物的敏感性及产超广谱β-内酰胺酶(ESBLs)情况,结果显示分离株对四环素、头孢噻呋、头孢吡肟、头孢噻肟和头孢唑林的耐药率较高(23.7%~41.0%)。16.9%(45/266)的分离株为多重耐药菌,6.4%(17/266)的分离株产ESBLs。结果提示,新疆15家规模化奶牛场乳腺炎肺炎克雷伯菌平均分离率在全国处于相对较低水平。分离株对四环素和头孢类抗菌药物具有较强的耐药性,本研究为掌握奶牛乳腺炎肺炎克雷伯菌的流行特征及指导临床用药提供了依据。 展开更多
关键词 奶牛乳腺炎 肺炎克雷伯菌 分离鉴定 耐药特性
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山羊伪结核棒状杆菌的分离与鉴定
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作者 陈曦 姜悦才 +6 位作者 刘明杰 李登亮 李少飞 曹启航 戚宇旭 刘军 马文涛 《动物医学进展》 北大核心 2026年第2期132-136,共5页
为探究某羊场羊颈部、腹股沟出现明显脓肿的病因,通过临床检查与ELISA血清抗体检测分离鉴定病原菌,并通过山羊回归试验验证其致病性。结果显示,分离得到一株有β溶血现象的伪结核棒状杆菌(Corynebacterium pseudotuberculosis,CP),其CP... 为探究某羊场羊颈部、腹股沟出现明显脓肿的病因,通过临床检查与ELISA血清抗体检测分离鉴定病原菌,并通过山羊回归试验验证其致病性。结果显示,分离得到一株有β溶血现象的伪结核棒状杆菌(Corynebacterium pseudotuberculosis,CP),其CP特异性16S rDNA基因、pLd基因与CP标准株序列同源性分别为100%和98%。该分离株在山羊回归试验中,能诱发典型脓肿病变,且从病变组织中重新分离鉴定出该菌株,最终确定引起该羊场羊只脓肿发生的病因为CP感染。 展开更多
关键词 干酪性淋巴结炎 伪结核棒状杆菌 pLd基因 山羊 分离鉴定
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基于缩比设计的弹性安装设备冲击响应影响规律分析
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作者 陈攀 魏强 +1 位作者 陈威 刘志忠 《舰船科学技术》 北大核心 2026年第2期46-51,共6页
针对舰船设备在水下爆炸冲击下的安全性问题,通过1∶3缩比模型数值模拟,探究实际加工和安装等偏差对设备基础冲击响应的影响规律。建立实尺度与缩比模型,分析质心偏移、隔振器数量、刚度及阻尼变化对缩比模型基础垂向加速度、速度、位... 针对舰船设备在水下爆炸冲击下的安全性问题,通过1∶3缩比模型数值模拟,探究实际加工和安装等偏差对设备基础冲击响应的影响规律。建立实尺度与缩比模型,分析质心偏移、隔振器数量、刚度及阻尼变化对缩比模型基础垂向加速度、速度、位移的影响。研究表明设备质心偏移、隔振器数量及刚度变化(±20%)对基础加速度峰值影响小于5%,速度与位移的影响可忽略;隔振器阻尼变化(±20%)导致加速度峰值差异达11%,需重点关注。研究结果阐明了舰船设备缩比模型简化规律,为舰船缩比模型设计及抗冲击性能评估提供借鉴作用。 展开更多
关键词 水下爆炸 缩比模型 弹性安装设备 冲击响应 隔振器参数
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江苏葫芦科作物上西瓜银斑驳病毒的侵染与分子鉴定
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作者 杨柳 孙枫 +2 位作者 高晓晓 任春梅 季英华 《江苏农业学报》 北大核心 2026年第1期41-50,共10页
西瓜银斑驳病毒(Watermelon silver mottle virus,WSMoV)是正番茄斑萎病毒属(Orthotospovirus)的重要成员,由蓟马传播,可侵染葫芦科、茄科等多种作物。为明确江苏蔬菜作物上WSMoV的侵染情况、分子特征及传播来源,本研究于2023-2024年在... 西瓜银斑驳病毒(Watermelon silver mottle virus,WSMoV)是正番茄斑萎病毒属(Orthotospovirus)的重要成员,由蓟马传播,可侵染葫芦科、茄科等多种作物。为明确江苏蔬菜作物上WSMoV的侵染情况、分子特征及传播来源,本研究于2023-2024年在江苏省主要蔬菜产区采集218份疑似WSMoV感染的葫芦科作物样品,采用RT-PCR、克隆测序等技术进行病原鉴定,并将鉴定得到的WSMoV与美国国家生物信息中心数据库登录的WSMoV氨基酸序列和碱基序列进行相似性分析和系统进化树构建,分析江苏WSMoV的可能传播来源。结果表明,来自南京市江宁区、南通市海门区、徐州市贾汪区的10份黄瓜样品检测到WSMoV侵染,样品带毒率为4.59%。江苏3个地区WSMoV分离物N基因差异较大,相似度仅为91.91%。其中,徐州市贾汪区分离物(登录号PV177960)和南通市海门区分离物(登录号PV177961)序列一致,与分离物WSMoV-SJZ(登录号PQ073372)的相似度较高,并在系统进化树中聚为同一分支;而南京市江宁区分离物(登录号PV177962)与分离物THBC(登录号PQ310671)和分离物HNTG(OQ715365)相似度较高,并在系统进化树中聚为同一分支,说明感染江苏黄瓜的WSMoV可能来源于不同的地区。本研究首次报道了WSMoV在江苏蔬菜作物上的发生状况,对该病毒的传播、流行及防治策略制定具有重要意义。 展开更多
关键词 西瓜银斑驳病毒 发生 分布 分子鉴定 江苏分离物 系统进化分析
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应用于地铁的隔振屏障措施研究
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作者 徐平 杨延峰 +2 位作者 岳帅 刘向明 韩月旺 《地震工程学报》 北大核心 2026年第3期501-511,共11页
以邻近7层建筑的郑州某地铁线路为工程背景,采用有限元软件ABAQUS建立车辆-轨道-隧道-土体-建筑的三维数值模型,通过对比分析数值模拟和现场实测的振动数据,验证数值模型的准确性和假定条件设立的合理性。研究针对传统空沟和混凝土连续... 以邻近7层建筑的郑州某地铁线路为工程背景,采用有限元软件ABAQUS建立车辆-轨道-隧道-土体-建筑的三维数值模型,通过对比分析数值模拟和现场实测的振动数据,验证数值模型的准确性和假定条件设立的合理性。研究针对传统空沟和混凝土连续墙,分析屏障厚度和深度对隔振效果的影响,并结合两者的隔振优势,提出混凝土空心墙和刚柔结合混凝土墙两种新型屏障,对四类屏障的隔振性能进行对比分析。结果表明:四类屏障的隔振效果均随深度增大而提高,且受屏障厚度的影响不明显;考虑工程造价和隔振效果,四类屏障深度可取至隧道底埋深;混凝土空心墙隔振效果比混凝土地连续墙提高0.8 dB,增幅较小;刚柔结合混凝土墙隔振效果比混凝土地连续墙提高2.7 dB,增幅较大,整体隔振效果与空沟接近;综合考虑地铁隧道埋深、空沟维护成本和耐久性、四类屏障的隔振效果及影响因素,建议采用刚柔结合混凝土墙对邻近地铁线路的建筑进行隔振防护。研究成果可为国内地铁的振动评价和隔振减振设计提供依据。 展开更多
关键词 地铁 振动信号 空沟 混凝土连续墙 新型隔振屏障 隔振效果
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