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全国统一大市场背景下中国CPI-PPI背离的传导阻滞机制与市场分割效应研究
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作者 程胜 熊星彤 《江南大学学报(人文社会科学版)》 2025年第6期47-58,共12页
基于2012年以来中国CPI与PPI持续背离的“价格剪刀差”现象,本文通过构建2005-2022年八大宏观价格指数的全产业链价格传递网络,创新性构建多时间尺度分析框架,综合MODWT分解、Vine Copula依赖网络与贝叶斯网络模型,系统解析了价格传导... 基于2012年以来中国CPI与PPI持续背离的“价格剪刀差”现象,本文通过构建2005-2022年八大宏观价格指数的全产业链价格传递网络,创新性构建多时间尺度分析框架,综合MODWT分解、Vine Copula依赖网络与贝叶斯网络模型,系统解析了价格传导的动态机制。研究发现:第一,价格传导呈现显著得多时间尺度非对称性,长期关联性最强,CPI与PPI通过CGPI、RPI双枢纽节点形成双向传导路径,但短期受临时冲击显著弱化;第二,CPI-PPI背离的核心阻滞链为CGPI→PPI→PPIRM,价格信号传递存在超过8个月的系统性时滞,导致上下游价格脱敏,该阻滞进一步延伸至IPI→EPI链加剧了结构性分化;第三,市场分割在长期显著削弱价格网络关联性,尤其在极端分位数下破坏效应加剧,其累积效应通过抑制要素跨区域流动、加剧资源错配传导至价格体系。基于此,本文提出破除CPI-PPI传导链时滞瓶颈、降低市场分割程度、推动全国统一大市场建设等政策建议,通过优化产业链协同机制、消除行政壁垒、强化要素跨区域流动,实现“阻滞疏解→协同强化”的高质量发展路径。 展开更多
关键词 全国统一大市场 价格网络 CPI-ppi背离 市场分割 要素流动
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PEK-PPI/CF耐磨复合材料的制备与性能 被引量:1
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作者 王向地 孙雁宾 +4 位作者 王志超 夏英 王书唯 王志鹏 李晓丹 《大连工业大学学报》 2025年第2期92-97,共6页
以无定形聚芳醚酮(PEK-PPI)为基体树脂,碳纤维(CF)为耐磨填料,采用球磨机粉末共混法和高温模压法制备了PEK-PPI/CF耐磨复合材料,探究了碳纤维长度和含量对PEK-PPI/CF复合材料摩擦磨损性能和力学性能的影响。研究结果表明,碳纤维的引入... 以无定形聚芳醚酮(PEK-PPI)为基体树脂,碳纤维(CF)为耐磨填料,采用球磨机粉末共混法和高温模压法制备了PEK-PPI/CF耐磨复合材料,探究了碳纤维长度和含量对PEK-PPI/CF复合材料摩擦磨损性能和力学性能的影响。研究结果表明,碳纤维的引入有利于转移膜的形成,摩擦系数降低,同时可以有效提升PEK-PPI/CF复合材料的耐磨性能。碳纤维越长、含量越高,PEK-PPI/CF复合材料的体积磨损率越低,耐磨性越好。当碳纤维为50目、质量分数为40%时,复合材料体积磨损率达到最小值5.782×10^(-16),耐磨性较纯PEK-PPI树脂提升两个数量级。碳纤维加入后,复合材料的导热系数明显提高,便于摩擦点附近温度的扩散,有利于降低体积磨损率。 展开更多
关键词 无定形聚芳醚酮 碳纤维 复合材料 耐磨材料
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PPI:供求改善 降幅收窄
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作者 叶芸 《四川省情》 2025年第1期34-35,共2页
随着一系列存量政策和增量政策协同发力,2024年11月PPI同比降幅较上月收窄0.3个百分点,是自2024年6月以来降幅首次收窄。预计2025年PPI价格保持低位运行。受国内工业品市场低迷影响,2024年1—11月四川工业生产者出厂价格(PPI)同比下降2.... 随着一系列存量政策和增量政策协同发力,2024年11月PPI同比降幅较上月收窄0.3个百分点,是自2024年6月以来降幅首次收窄。预计2025年PPI价格保持低位运行。受国内工业品市场低迷影响,2024年1—11月四川工业生产者出厂价格(PPI)同比下降2.0%,降幅比2023年收窄0.4个百分点,其中一季度下降1.8%,二季度下降1.3%,三季度下降2.3%, 10—11月下降3.1%;1—11月四川工业生产者购进价格同比下降2.6%,降幅比2023年收窄0.3个百分点,其中一季度下降3.5%,二季度下降2.3%,三季度下降1.6%,10—11月下降3.4%。 展开更多
关键词 购进价格 低位运行 ppi 工业生产者出厂价格 市场低迷
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IMiDs作为PPI稳定剂在蛋白质降解方面的研究进展 被引量:1
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作者 宋冰茹 袁大中 《药物化学》 2025年第1期49-60,共12页
在过去的二十年里,随着IMiD和indisulam等MG降解剂的出现,分子胶(MGs)逐渐引起了制药界的关注。这些分子通过促进靶蛋白和E3连接酶之间的相互作用来降解靶蛋白。此外,MGs作为化学诱导剂,促进同源蛋白和异源蛋白的二聚化形成三元复合物,... 在过去的二十年里,随着IMiD和indisulam等MG降解剂的出现,分子胶(MGs)逐渐引起了制药界的关注。这些分子通过促进靶蛋白和E3连接酶之间的相互作用来降解靶蛋白。此外,MGs作为化学诱导剂,促进同源蛋白和异源蛋白的二聚化形成三元复合物,在调节生物活性方面具有很大的前景。本文重点介绍MGs在药物开发领域的应用,包括蛋白质–蛋白质相互作用(PPI)稳定性和蛋白质降解。我们深入分析了各种MGs的结构以及MGs与各种生物活性分子之间的相互作用,从而为PPI稳定剂和新型降解剂的开发提供了新的视角。Over the past two decades, molecular glues (MGs) have gradually attracted the attention of the pharmaceutical community with the advent of MG degraders such as IMiDs and indisulam. Such molecules degrade the target protein by promoting the interaction between the target protein and E3 ligase. In addition, as a chemical inducer, MGs promote the dimerization of homologous proteins and heterologous proteins to form ternary complexes, which have great prospects in regulating biological activities. This review focuses on the application of MGs in the field of drug development including protein-protein interaction (PPI) stability and protein degradation. We thoroughly analyze the structure of various MGs and the interactions between MGs and various biologically active molecules, thus providing new perspectives for the development of PPI stabilizers and new degraders. 展开更多
关键词 蛋白质–蛋白质相互作用 分子胶 ppi稳定剂 降解剂
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中国CPI与PPI的动态演变特征及时变传导机制研究
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作者 于学霆 《统计与决策》 北大核心 2025年第12期118-123,共6页
文章基于2011年1月至2023年8月中国CPI、PPI的月度数据,借助驱动因素分解、带有异常值调整的不可观测成分随机波动(UCSVO)模型、时变格兰杰因果检验等方法,深入分析了中国CPI与PPI的动态演变特征及时变传导机制。结果显示:中国CPI和PPI... 文章基于2011年1月至2023年8月中国CPI、PPI的月度数据,借助驱动因素分解、带有异常值调整的不可观测成分随机波动(UCSVO)模型、时变格兰杰因果检验等方法,深入分析了中国CPI与PPI的动态演变特征及时变传导机制。结果显示:中国CPI和PPI的动态演变过程和主导因素均不一致,存在趋势性和波动性双背离特征,构成成分的贡献特征也存在差异。在整个样本区间内,CPI与PPI呈现双向传导关系。在考虑时变特征的情形下,CPI与PPI之间的传导关系在不同时间点上差异较大。 展开更多
关键词 CPI ppi 传导机制 时变格兰杰因果检验
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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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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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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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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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旋覆代赭汤合小陷胸汤加减联合PPIs降阶梯撤药对非糜烂性反流病的效果
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作者 张安 《中国医学创新》 2025年第5期118-122,共5页
目的:探究旋覆代赭汤合小陷胸汤加减联合质子泵抑制剂(PPIs)降阶梯撤药治疗非糜烂性反流病(NERD)的效果。方法:选择2021年1月-2024年1月在清华大学第一附属医院治疗的NERD患者80例,根据随机数字表法分为两组,均40例,对照组采用PPIs降阶... 目的:探究旋覆代赭汤合小陷胸汤加减联合质子泵抑制剂(PPIs)降阶梯撤药治疗非糜烂性反流病(NERD)的效果。方法:选择2021年1月-2024年1月在清华大学第一附属医院治疗的NERD患者80例,根据随机数字表法分为两组,均40例,对照组采用PPIs降阶梯撤药治疗,试验组采用旋覆代赭汤合小陷胸汤加减联合PPIs降阶梯撤药治疗,两组在治疗12周后评价治疗效果,对比两组临床疗效、病情状况、胃肠自主神经功能、血清指标、生活质量。结果:试验组总有效率高于对照组(P<0.05)。治疗后,试验组反流性疾病问卷(RDQ)各项评分、胃肠自主神经功能低频功率(LF)值均高于对照组,胃肠自主神经功能高频功率(HF)值、5-羟色胺(5-HT)、血管活性肠肽(VIP)、胃食管反流病问卷(GerdQ)均低于对照组,差异均有统计学意义(P<0.05)。结论:NERD患者接受旋覆代赭汤合小陷胸汤加减联合PPIs降阶梯撤药治疗,效果显著,可改善胃肠自主神经功能及胃肠动力,提高生活质量。 展开更多
关键词 旋覆代赭汤合小陷胸汤加减 质子泵抑制剂 降阶梯撤药 非糜烂性反流病
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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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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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基础隔震结构抗连续倒塌机制试验研究
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作者 包超 田佳岐 +3 位作者 张宇航 马肖彤 杜永峰 杨秋宁 《工程科学与技术》 北大核心 2026年第1期181-191,共11页
隔震结构特殊的构造形式,使得现有抗震结构连续倒塌研究成果无法完全适用。为了研究基础隔震结构抗连续倒塌性能及其参数的影响规律,对3个1/3缩尺钢筋混凝土基础隔震子结构(普通橡胶隔震支座的子结构构件S1、铅芯橡胶隔震支座的子结构构... 隔震结构特殊的构造形式,使得现有抗震结构连续倒塌研究成果无法完全适用。为了研究基础隔震结构抗连续倒塌性能及其参数的影响规律,对3个1/3缩尺钢筋混凝土基础隔震子结构(普通橡胶隔震支座的子结构构件S1、铅芯橡胶隔震支座的子结构构件S2,以及带有翼缘板的基础隔震子结构构件S3)分别开展非线性静力推覆试验研究,对比分析了试件的受力状态与破坏模式。结果表明:3个试件的破坏主要发生在弯矩较大区域,即中柱附近,而边柱节点均未出现裂缝;基础隔震结构试件的侧向约束作用较弱,难以形成悬链线机制,其抗力机制主要分为梁机制和复合机制两个阶段;基础隔震结构其转角位移与水平位移使得中柱梁端形成塑性铰的子结构具备转动的变形能力,从而延缓框架梁端塑性铰的失效,提高结构的抗连续倒塌性能;楼板拉结作用可以提升基础隔震抗连续倒塌能力;隔震层水平刚度的提高对基础隔震结构的抗连续倒塌剩余能力影响不大。 展开更多
关键词 基础隔震结构 连续倒塌 倒塌抗力 pushdown分析方法 失效模式
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