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Defence Technology（防务技术） 2024年第3期33卷 66-77页

作者： Tihomir Kovacevic Slavko Mijatov Jelena Grzetic Suzana Cakic Bojana Fidanovski sasa Brzic Military Technical Institute Ministry of DefenceRatka Resanovica 1BelgradeSerbia Faculty of Technology University of NisBulevar osloboCenja 124LeskovacSerbia

Conventional plasticizers deteriorate mechanical and viscoelastic properties of the propellants due to their migration upon aging and long-term storage,which affects reliability and safety properties during *** address this issue,conventional plasticizer,dioctyl adipate(DOA),is replaced by reactive one,castor oil(CO).In addition,three different types of HTPB were used to obtain propellants with designed viscoelastic and mechanical *** CO increased propellants viscosity,without a significant impact on the propellant processability,regardless to the type of ***,mechanical properties were different depending on the type of resin,which were further analyzed by gel permeation chromatography(GPC).Addition of CO formed a denser polymer network and shifted T_(g) to higher values,compared to the compositions with *** tensile strength of CO-containing propellants was lower at +20℃ and +50℃ compared to the reference compositions,while the strain at maximum load and strain at break were significantly increased with pronounced plastic deformation,especially for samples at -30℃.The inclusion of CO in the propellants composition gives more room for adjusting a wide range of mechanical properties.

关键词： HTPB-based composite propellants Castor oil Reactive plasticizer Gel permeation chromatography Sol-gel analysis Mechanical and viscoelastic properties

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激光散射特性的红外瞄准镜基线检测方法

激光杂志 2024年第7期45卷 227-232页

作者：李波莎日娜内蒙古医科大学呼和浩特010110 中国人民解放军32302部队50分队北京101400

为提升武器射击精度,设计激光散射特性的红外瞄准镜基线检测方法。通过固定瞄准镜并利用黑体发射红外激光,在镜子反射后形成红外平行光束,并在瞄准镜视场内生成靶标的像。通过调整瞄准镜分划中心与靶标像中心重合,实现基线检测。采用双... 详细信息

为提升武器射击精度,设计激光散射特性的红外瞄准镜基线检测方法。通过固定瞄准镜并利用黑体发射红外激光,在镜子反射后形成红外平行光束,并在瞄准镜视场内生成靶标的像。通过调整瞄准镜分划中心与靶标像中心重合,实现基线检测。采用双向反射分布函数和基尔霍夫近似理论的驻留相位近似法,分析红外激光的散射特性及波长与散射角对成像精度的影响,从而提高基线检测的精度。实验证明:当入射波长在9.5μm左右时,射击目标粗糙度为8μm时,双站极化散射系数最低,在1.0左右;当散射角在29°左右时,射击目标粗糙度为8μm时,双站极化散射系数最低在0.146左右;校正后目标位置偏差平均为0.01 m。

关键词：激光散射特性红外瞄准镜基线检测反射分布函数基尔霍夫驻留相位近似法

Development of a new Cox model for predicting long-term survival in hepatitis cirrhosis patients underwent transjugular intrahepatic portosystemic shunts

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 491-502页

作者： Yi-Fan Lv Bing Zhu Ming-Ming Meng Yi-Fan Wu Cheng-Bin Dong Yu Zhang Bo-Wen Liu Shao-Li You sa Lv Yong-Ping Yang Fu-Quan Liu Liver Disease Minimally Invasive Diagnosis and Treatment Center Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Liver Vascular Disease Diagnosis and Treatment Center The Fifth Medical Center of Chinese People's Liberation Army General HospitalBeijing 100039China

BACKGRouND Transjugular intrahepatic portosystemic shunt(TIPS)placement is a procedure that can effectively treat complications of portal hypertension,such as variceal bleeding and refractory ***,there have been no specific studies on predicting long-term survival after TIPS *** To establish a model to predict long-term survival in patients with hepatitis cirrhosis after *** A retrospective analysis was conducted on a cohort of 224 patients who un-derwent TIPS *** univariate and multivariate Cox regression analyses,various factors were examined for their ability to predict survival at 6 years after ***,a composite score was formulated,encompassing the indication,shunt reasonability,portal venous pressure gradient(PPG)after TIPS,percentage decrease in portal venous pressure(PVP),indocyanine green retention rate at 15 min(ICGR15)and total bilirubin(Tbil)***,the performance of the newly developed Cox(NDC)model was evaluated in an in-ternal validation cohort and compared with that of a series of existing *** The indication(variceal bleeding or ascites),shunt reasonability(reasonable or unreasonable),ICGR15,post-operative PPG,percentage of PVP decrease and Tbil were found to be independent factors affecting long-term survival after TIPS *** NDC model incorporated these parameters and successfully identified patients at high risk,exhibiting a notably elevated mortality rate following the TIPS procedure,as observed in both the training and validation ***,in terms of predicting the long-term survival rate,the performance of the NDC model was significantly better than that of the other four models[Child-Pugh,model for end-stage liver disease(MELD),MELD-sodium and the Freiburg index of post-TIPS survival].CONCLUSION The NDC model can accurately predict long-term survival after the TIPS procedure in patients with hepatitis cirrhosis,help identify high-risk patients

关键词： Transjugular intrahepatic portosystemic shunt Long-term survival Predictive model

CXCL12/CXCR4轴在HIV感染及艾滋病中医证候中的研究现状

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中国免疫学杂志 2024年第6期40卷 1297-1301页

作者：陈晓宇谢世平张淼刘飒马素娜王娟河南中医药大学郑州450046

机体CXCL12/CXCR4的结构及生物学作用是生理病理功能的基础。HIV-1包膜蛋白与CXCR4结合会促进病毒进入宿主细胞,CXCL12能通过快速内吞作用减少CXCR4的数量抑制HIV的复制及传播。CXCL12/CXCR4轴与炎症、自噬的相互作用在HIV感染中发挥重... 详细信息

机体CXCL12/CXCR4的结构及生物学作用是生理病理功能的基础。HIV-1包膜蛋白与CXCR4结合会促进病毒进入宿主细胞,CXCL12能通过快速内吞作用减少CXCR4的数量抑制HIV的复制及传播。CXCL12/CXCR4轴与炎症、自噬的相互作用在HIV感染中发挥重要作用。研究发现艾滋病不同中医证候的基因表达谱不同,CXCR4在艾滋病肺脾气虚证、气阴两虚证和湿热内蕴证中的表达具有差异,涉及趋化因子信号通路;在艾滋病肺脾气虚证患者外周血中差异基因CXCR4与自噬过程相关,对该证型患者进行中药益艾康胶囊干预,CXCR4表达升高,提示中药益艾康胶囊可以调控自噬相关基因的表达。研究CXCL12/CXCR4在艾滋病中医证候中的作用,有利于更好地发挥中医药的治疗优势,为基因的靶向治疗提供新的方向。

关键词： CXCL12/CXCR4 HIV感染艾滋病中医证候研究现状

Kinetic modeling of high-temperature oxidation of pure Mg

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Journal of magnesium and Alloys 2020年第3期8卷 819-831页

作者： sa ma Fangzhou Xing Na Ta Lijun Zhang State Key Laboratory of Powder Metallurgy Central South UniversityChangshaHunan 410083P.R.China max-Planck-Institut fiir Eisenforschung GmbH Max-Planck-Straβe 140237DusseldorfGermany

A variety of experimental tracer diffusivities of Mg and O in magnesium oxide available in the literature were first *** mobilities including bulk and short-circuit diffusion of Mg and O were then obtained by means of the CALPHAD(Calculation of Phase Diagram)***,the diffusion-controlled kinetic model of oxidation in a gas-MgO-Mg environment was developed based on the moving boundary model and Fick's law,coupling with the modified thermodynamic description of MgO.A mathematical expression for parabolic rate constant kp of the oxide scale was derived for magnesia and correlated with the thermodynamic and diffusion kinetic *** evaluated kp results were in line with the experimental ***,the oxidation process of pure magnesium at 673 K was model-predicted,and the predicted evolution of the oxide thicknesses agreed very well with the experimental *** was indicated that the grain boundaries diffusion of magnesium cations predominated the high temperature oxidation process.

关键词： MgO Diffusion Oxidation Atomic mobility CALPHAD Wagner's model

Non-thermal atmospheric-pressure positive pulsating corona discharge in degradation of textile dye Reactive Blue 19 enhanced by Bi_(2)O_(3) catalyst

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Plasma Science and Technology 2024年第2期26卷 104-113页

作者： Milica PETROVIC Dragan RADIVOJEVIC sasa RANCEV Nena VELINOV Milos KOSTIC Danijela BOJIC Aleksandar BOJIC Department of Chemistry Faculty of Sciences and MathematicsUniversity of NisNis 18000Serbia Department of Physics Faculty of Sciences and MathematicsUniversity of NisNis 18000Serbia

In this work,monoclinic Bi_(2)O_(3) was applied for the first time,to the best of our knowledge,as a catalyst in the process of dye degradation by a non-thermal atmospheric-pressure positive pulsating corona *** research focused on the interaction of the plasma-generated species and the catalyst,as well as the role of the catalyst in the degradation *** decomposition of the anthraquinone reactive dye Reactive Blue 19(RB 19) was performed in a selfmade reactor ***_(2)O_(3) was prepared by electrodeposition followed by thermal treatment,and characterized by x-ray diffraction,scanning electron microscopy and energy-dispersive xray *** was observed that the catalyst promoted decomposition of plasma-generated H_(2)O_(2) into ·OH radicals,the principal dye-degrading reagent,which further attacked the dye *** catalyst improved the decolorization rate by 2.5 times,the energy yield by 93.4%and total organic carbon removal by 7.1%.Excitation of the catalyst mostly occurred through strikes by plasma-generated reactive ions and radical species from the air,accelerated by the electric field,as well as by fast electrons with an energy of up to 15 eV generated by the streamers reaching the liquid *** strikes transferred the energy to the catalyst and created the electrons and holes,which further reacted with H_(2)O_(2) and water,producing ·OH *** was indentified as the primary role of the catalyst in this *** reactions followed pseudo first-order *** of H_(2)O_(2) and the dye degradation rate increased with increase in the input *** optimal catalyst dose was 500 mg·dm^(-3).The decolorization rate was a little lower in river water compared with that in deionized water due to the side reactions of ·OH radicals with organic matter and inorganic ions dissolved in the river water.

关键词： corona RB 19 Bi_(2)O_(3) catalyst degradation

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非物质文化遗产保护中习惯规则的价值探析

贵州民族研究 2024年第2期45卷 171-176页

作者：萨矗荣贵中国人民大学法学院北京100872

非物质文化遗产本身蕴含着丰富的习惯规则内容,这些传统的习惯规则在文化传承中发挥着正式规范所无法替代的作用。习惯规则主要通过口头传承的方式得以延续,并由习惯机构依据传统社区和群体的文化价值观执行,旨在保护非物质文化遗产的... 详细信息

非物质文化遗产本身蕴含着丰富的习惯规则内容,这些传统的习惯规则在文化传承中发挥着正式规范所无法替代的作用。习惯规则主要通过口头传承的方式得以延续,并由习惯机构依据传统社区和群体的文化价值观执行,旨在保护非物质文化遗产的社会和文化利益,确保群体内成员享有平等的权利义务。根据传统习惯,非遗是集体所共有的,其使用伦理依赖于习惯规则和群体内部的社会关系。因此习惯规则在保护集体权利方面发挥着重要作用。沿袭多年的习惯规则与非遗所在的地域和群体紧密相连,与现代法治互补并存,共同发挥作用。在非遗保护价值观上,二者的一致性能使它们相互呼应,共同维护非遗的传承与发展。

关键词：习惯规则集体利益合理使用现代价值

从《沈阳百咏》探析光绪初年盛京城人居文化景观

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风景园林 2024年第6期31卷 133-139页

作者：谢淼伊娜王飒沈阳建筑大学建筑与规划学院沈阳建筑大学辽宁省区域建筑学与寒地人居科学重点实验室

【目的】从人居环境学的角度,探究在清末外部变化影响下仍是帝国陪都的盛京城内文化景观和城市空间变化,以填补盛京城清末文化景观研究的不足。【方法】以《沈阳百咏》为依据,运用文本挖掘语义分析、时间地理学分析、历史地理空间分析... 详细信息

【目的】从人居环境学的角度,探究在清末外部变化影响下仍是帝国陪都的盛京城内文化景观和城市空间变化,以填补盛京城清末文化景观研究的不足。【方法】以《沈阳百咏》为依据,运用文本挖掘语义分析、时间地理学分析、历史地理空间分析量化光绪初年盛京城人居文化景观类型和时空信息,探讨文化景观的分布规律,并通过对比清朝前、中、末期城市空间,总结光绪初年盛京城的风貌特点。【结果】将盛京城人居文化景观归纳为“游憩玩赏”“盛京旧制”“市井生活”“信俗集会”4个一级分类及15个二级分类,发现文化景观类型与季节农时有强关联,不同文化景观在地理空间分布上有显著差异,整体上集中于关厢地带,城北景观密度高于城南。通过将《沈阳百咏》中城市空间与清前、中期城市空间对比发现,光绪初年盛京城已成为有满族特色的地方中心性城市。【结论】对《沈阳百咏》的深入挖掘填补了清末盛京城文化景观研究的缺环,为清代盛京城研究提供新思路,同时也为后续通过诗文分析盛京城文化景观格局提供了参考。

关键词：文化景观人居环境学诗词文本挖掘时空结构清代盛京城

Solitary Osteogenic Exostosis of the Femur Revealed by Recurring Acute Distal Thigh Pain: About a Case

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Open Journal of Pediatrics 2024年第4期14卷 719-726页

作者： Thierno saïdou Barry Mohamed Lamine sadou sacko Balla Keita Sory Sidimé Moussa Condé Daniel Agbo-Panzo Pediatric Surgery Department Donka National Hospital (HND) of the University Hospital of Conakry Gamal Abdel Nasser University of Conakry (UGANC) of Guinea Conakry Guinea Orthopedic and Trauma Surgery Department Donka National Hospital (HND) of the Conakry University Hospital Conakry Guinea

Introduction: Solitary exostoses are the most common benign tumors of the fertile metaphyses of the long bones of children. Their radiological diagnosis of metaphyseal bone growth must be confirmed on pathological examination. These tumors can remain asymptomatic for a long time and reveal themselves during a particularly vascular complication. The objective of this study was to describe the epidemiological, diagnostic, therapeutic and evolutionary aspects of these tumors. Patient and Observation: We report the case of a 15-year-old adolescent girl, with no particular pathological history, received in the pediatric surgery department of the Donka National Hospital (HND) of the Conakry University Hospital for recurrent acute painful swelling of the lower third of the left thigh in an afebrile context accompanied by lameness and stopping school for a few days (2 - 3 days). The symptoms appear to have evolved over the past 3 years and after physical activities. It regresses with rest, analgesics and non-steroidal anti-inflammatory drugs. The notion of trauma and sickle cell disease was not reported in the patient's clinical history. It is the persistence of the symptomatology which motivates the said consultation. On palpation, a small hard mass is noted at the expense of the internal metaphysis of the left distal femur. Deep palpation of this area causes a tingling sensation and during rapid mobilization of the knee. The remainder of the orthopedic examination was unremarkable. Standard x-ray of the femur shows a bony growth with a pointed tip from the distal metaphysis of the left femur. On surgical exploration, we noted a wedge-shaped exostosis oriented towards the vastus medialis muscle. Histological examination of the surgical specimen confirms osteogenic exostosis. There is no recurrence after 2 years. Conclusion: The distal femoral metaphysis is the most common location of solitary osteochondromas in children. Their definitive diagnosis requires the histology of

关键词： Osteogenic Exostosis Osteochondromas Fertile Long Bone Metaphyses Child

Local Criteria Used by Farmers to Evaluate the Agronomic Performance and the Fertilizing Capacity of Cowpea Varieties: Diversity, Variability and Proximal Relation with Agronomic Measurements in Contrasted sahelian Locations

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Agricultural Sciences 2024年第1期15卷 114-131页

作者： Nouhou salifou Jangorzo Abdoul-Aziz saïdou Abou-Soufianou sadda Abdoulaye Moussa mamoudou Hassane Bil-Assanou Issoufou Département des Sciences du Sol et Télédétection Université Dan Dicko Dankoulodo de Maradi Maradi Niger. Unité Mixte de Recherche “Diversité et Adaptation des Plantes” (UMR DAP) Université Dan Dicko Dankoulodo de Maradi Maradi Niger Centre Imaan de Support en Recherche Transdisciplinaire (Imaan Research) Niamey Niger Institut de Recherche pour le Développement Niamey Niger Université Boubacar BA de Tillabéri Tillabéri Niger Département des Sciences et Techniques de Productions Végétales Université Dan Dicko Dankoulodo de Maradi Maradi Niger

When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific criteria they individually use to attribute a score are not well described. The objectives of this work were to: 1) identify and describe exhaustively the local criteria used by farmers to measure the agronomic performance of cowpea;2) assess the variability and statistical structure of these farmer criteria across local contexts;3) and analyze the association between these farmer criteria and the classical agronomic measurement. To achieve these objectives, an augmented block design was implemented across fifteen locations in the regions of maradi, Dosso and Tillabéri, representing a diversity of local contexts. From a set of 36 cowpea varieties, fifteen varieties were sown per location, including five varieties (controls) common to all locations. In each location, two replicates were sown in randomized Fisher’s blocks. After agronomic measurement and participatory evaluation (scoring of varieties by farmers), a group survey (focus group) was conducted in each location to identify the criteria considered by farmers to found their discretional scoring of varieties during the participatory evaluation. The analysis of the data identified, across locations, thirteen criteria defined by farmers to characterize the agronomic performance of cowpea. Some of these criteria were different according to location. Farmers ranked the three varieties with the best performance for each agronomical trait (Top 3 varieties). A comparison of the farmer ranking with the ranking based on agronomic measurements revealed similarity and complementary between both methods. This study highlighted the importance of considering both local and scientific knowledge in local varietal evaluations.

关键词： Agronomic Performance Participatory Research Cowpea Farmers’ Criteria