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超临界二氧化碳在螺杆挤出过程中塑化混合酯发射药的研究:在线流变仪设计与实验测量

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火炸药学报 2024年第2期47卷 188-196,I0004页

作者：顾晗应三九胡启鹏汪超南京理工大学化学与化工学院江苏南京210094 教育部特种能源材料重点实验室江苏南京210094

为了改善混合酯发射药的加工流动性,在其挤出过程中注入超临界二氧化碳(SC-CO_(2))作为增塑剂;为了更好地研究塑化过程,设计制造了一个在线狭缝流变仪用来测量混合酯发射药的剪切黏度和流变参数。流动曲线表明,混合酯发射药和SC-CO_(2)... 详细信息

为了改善混合酯发射药的加工流动性,在其挤出过程中注入超临界二氧化碳(SC-CO_(2))作为增塑剂;为了更好地研究塑化过程,设计制造了一个在线狭缝流变仪用来测量混合酯发射药的剪切黏度和流变参数。流动曲线表明,混合酯发射药和SC-CO_(2)/发射药混合物都是非牛顿假塑性流体,幂律模型可以用来描述SC-CO_(2)/发射药混合物的流变行为。实验研究了剪切黏度随加工温度和增塑剂含量的变化规律,结果显示较高的加工温度有利于降低剪切黏度。在注入SC-CO_(2)后,黏流活化能降低了约20 kJ/mol。SC-CO_(2)被证明是一种有效的增塑剂,可以显著改善混合酯发射药的流动性。并且随着SC-CO_(2)含量的增加,挤出过程中的流动性会更好,但增塑剂含量的不断增加并不能无限制地提升塑化效果。

关键词：物理化学混合酯发射药超临界二氧化碳流变仪塑化增塑剂

基于北斗导航系统的三频载波相位高精度时间长距离传递方法研究

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南京理工大学学报 2024年第3期48卷 293-299页

作者：彭恒范城城北京航天长城卫星导航科技有限公司北京100032 中国科学院微小卫星创新研究院上海201210 上海微小卫星工程中心上海201210 中国科学院卫星数字化技术重点实验室上海201210

全球导航卫星系统(GNSS)是高精度时间长距离传递技术重要应用手段。针对高精度时间长距离传递受限于全球定位系统(GPS)载波信号组合的问题,该文提出一种基于北斗导航系统(BDS)的三频载波相位高精度时间长距离传递方法。分别对BDS不同载... 详细信息

全球导航卫星系统(GNSS)是高精度时间长距离传递技术重要应用手段。针对高精度时间长距离传递受限于全球定位系统(GPS)载波信号组合的问题,该文提出一种基于北斗导航系统(BDS)的三频载波相位高精度时间长距离传递方法。分别对BDS不同载波信号B1、B2、B3进行两两组合,通过二次叠加无电离层,消弱各种全链路误差影响,验证了B12和B13组合时间传递精度最低,B13和B23组合时间传递精度最高,3种组合的时间传递均方根(RMS)误差差异不超过0.03 ns。与国际精密钟差产品比较,结果表明在2600 km的时间链上,基于BDS的三频载波相位的时间传递均方根误差小于0.244 ns,基于BDS的三频载波相位长距离时间传递可以实现亚纳秒级,可为全球导航卫星系统应用提供技术支撑。

关键词：北斗导航系统精密时间三频信号载波相位长距离

Metformin:A promising clinical therapeutical approach for BPH treatment via inhibiting dysregulated steroid hormones-induced prostatic epithelial cells proliferation

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Journal of Pharmaceutical Analysis 2024年第1期14卷 52-68页

作者： Tingting Yang Jiayu Yuan Yuting peng Jiale Pang Zhen Qiu Shangxiu Chen Yuhan Huang Zhenzhou Jiang Yilin fan Junjie Liu Tao Wang Xueyan Zhou Sitong Qian Jinfang Song Yi Xu Qian Lu Xiaoxing Yin Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy Xuzhou Medical UniversityXuzhouJiangsu221004China Department of Pharmacy Affiliated Lianyungang Hospital of Xuzhou Medical UniversityLianyungangJiangsu222061China Department of Pharmacy The Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu221006China New Drug Screening Center Jiangsu Center for Pharmacodynamics Research and EvaluationChina Pharmaceutical UniversityNanjing210009China School of Life Sciences University of EssexEssex CO43SQUnited Kingdom Department of Urology The Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu221006China Department of Pharmacy Affiliated Hospital of Jiangnan UniversityWuxiJiangsu214000China

The occurrence of benign prostate hyperplasia(BPH)was related to disrupted sex steroid hormones,and metformin(Met)had a clinical response to sex steroid hormone-related gynaecological ***,whether Met exerts an antiproliferative effect on BPH via sex steroid hormones remains ***,our clinical study showed that along with prostatic epithelial cell(PEC)proliferation,sex steroid hormones were dysregulated in the serum and prostate of BPH *** the major contributor to dysregulated sex steroid hormones,elevated dihydrotestosterone(DHT)had a significant positive relationship with the clinical characteristics of BPH *** of adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)by Met restored dysregulated sex steroid hormone homeostasis and exerted antiproliferative effects against DHT-induced proliferation by inhibiting the formation of androgen receptor(AR)-mediated Yes-associated protein(YAP1)-TEA domain transcription factor(TEAD4)***’s anti-proliferative effects were blocked by AMPK inhibitor or YAP1 overexpression in DHT-cultured BPH-1 *** findings indicated that Met would be a promising clinical therapeutic approach for BPH by inhibiting dysregulated steroid hormone-induced PEC proliferation.

关键词： Metformin Benign prostatic hyperplasia Sex steroid hormones homeostasis Proliferation DHT YAP1-TEAD4 heterodimer

Gibbon vocal communication provides insights into the origin and evolution of human music and language

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Zoological Research(Diversity and Conservation) 2024年第2期1卷 130-132页

作者： Zi-Di Wang Hai-Gang Ma peng-Fei fan School of Life Sciences Sun Yat-Sen UniversityGuangzhouGuangdong 510275China

Humans across cultures convey feelings and thoughts through *** its ubiquity,the origins and evolution of music remain *** evidence has traced the history of music back at least 40000 years ago based on prehistoric bone flutes(Fitch,2006).Comparative studies have also explored earlier histories by identifying common musical features between animals and humans(Fitch,2006).For example,songbirds exhibit categorical rhythms similar to human music(Roeske et al.,2020),and humans can recognize emotional arousal in signals across all classes of terrestrial vertebrates(Filippi et al.,2017).These findings,while surprising,align with the longstanding human perception of animal signals as music(Gray et al.,2001).The universality of music and its features intensifies the fundamental question posed by Darwin(1871):how has a behavior that is energetically costly and seemingly non-adaptive evolved to become so widespread?This question can be further divided into two sub-questions(Savage et al.,2021):(1)how do musical features contribute to the production or expressive power of music(i.e.,mechanisms),and(2)how does music benefit performers in terms of survival,reproductions,or other aspects(i.e.,functions).

关键词： communication origin evolution

Nanodiamond:a promising metal-free nanoscale material in photocatalysis and electrocatalysis

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Rare Metals 2024年第8期43卷 3501-3552页

作者： Xiao-Wu Gao Zi-Wei Zhao Yang He Sai-Fei fan Ke-Ran Jiao Si-Yu Lou Xin-Yue Han peng-Fei Song Rong Cai Zhun Hu Zhong-Jie Jiang Yong-Jie Wang Jia-Qi Zhu Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems School of ScienceHarbin Institute of Technology National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology School of Advanced Technology Xi'an Jiaotong-Liverpool University Department of Biosciences Rice University Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi'an Jiaotong University Guangzhou Key Laboratory for Surface Chemistry of Energy Materials New Energy Research Institute & Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of Technology

Benefiting from its surface-rich functional groups,eco-friendliness,impressive electrochemical properties,excellent light absorption,structural tunability at the atomic/morphological level,and ultra-high stability under harsh conditions,nanodiamond has emerged as a promising carbon-based non-metallic material in the field of energy conversion such as electrocatalysis and ***,nanodiamond,as a new generation of green catalysts,can overcome the poisoning of catalysts by complex pollutants in advanced oxidation processes,thus effectively removing organic matter from water,which is unparalleled in reducing the cost of water purification and avoiding secondary cross-contamination of water by traditional heavy metal-based ***,we review the research and development of nanodiamonds as major electrocatalysts and photocatalysts for energy conversion and for air/water treatment for environmental *** relevant properties,trimming strategy,mechanistic understanding,and design principles of nanodiamond as a catalyst are described,as well as the challenges and prospects of this emerging field.

关键词： Carbon materials Nanodiamond Electrocatalysis Photocatalysis Energy conversion Pollutant treatment

FMSA:a meta-learning framework-based fast model stealing attack technique against intelligent network intrusion detection systems

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Cybersecurity 2024年第1期7卷 110-121页

作者： Kaisheng fan Weizhe Zhang Guangrui Liu Hui He School of Cyberspace Science Harbin Institute of TechnologyHarbin 150001China Department of New Networks Peng Cheng LaboratoryShenzhen 518055GuangdongChina

Intrusion detection systems are increasingly using machine *** machine learning has shown excellent performance in identifying malicious traffic,it may increase the risk of privacy *** paper focuses on imple-menting a model stealing attack on intrusion detection *** model stealing attacks are hard to imple-ment in practical network environments,as they either need private data of the victim dataset or frequent access to the victim *** this paper,we propose a novel solution called Fast Model Stealing Attack(FMSA)to address the problem in the field of model stealing *** also highlight the risks of using ML-NIDS in network ***,meta-learning frameworks are introduced into the model stealing algorithm to clone the victim model in a black-box ***,the number of accesses to the target model is used as an optimization term,resulting in minimal queries to achieve model ***,adversarial training is used to simulate the data distribution of the target model and achieve the recovery of privacy *** experiments on multiple public datasets,compared to existing state-of-the-art algorithms,FMSA reduces the number of accesses to the target model and improves the accuracy of the clone model on the test dataset to 88.9%and the similarity with the target model to 90.1%.We can demonstrate the successful execution of model stealing attacks on the ML-NIDS system even with protective measures in place to limit the number of anomalous queries.

关键词： AI security Model stealing attack Network intrusion detection Meta learning

qGW11a/OsCAT8,encoding an amino acid permease,negatively regulates grain size and weight in rice

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The Crop Journal 2024年第4期12卷 1150-1158页

作者： peng Gao Feifan Chen Haitang Liu Shijun fan Jierui Zeng Xue Diao Yang Liu Wencheng Song Shifu Wang Jing Li Xiaobo Zhu Bin Tu Weilan Chen Ting Li Yuping Wang Bingtian Ma Shigui Li Hua Yuan peng Qin State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Rice Research InstituteSichuan Agricultural UniversityChengdu 611130SichuanChina

Grain size is a key factor influencing grain weight in *** this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to its donor parent *** investigation identified two quantitative trait loci(QTL)on chromosome 11,designated qGW11a and qGW11b,which contribute to 1000-grain weight with an additive ***_Os11g05690,encoding the amino acid permease OsCAT8,is the target gene of *** of OsCAT8 resulted in decreased grain weight,while OsCAT8 knockout mutants exhibited increased grain *** 287-bp located within the OsCAT8 promoter region of 93-11 negatively regulates its activity,which is subsequently correlated with an increase in grain size and *** results suggest that OsCAT8 functions as a negative regulator of grain size and grain weight in rice.

关键词： Rice Grain size Grain weight QTL OsCAT8

Dipeptidyl peptidase-4 inhibitors and the risk of infection: A systematic review and meta-analysis of cardiovascular outcome trials

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World Journal of Diabetes 2024年第5期15卷 1011-1020页

作者： Na Yang Li-Yun He peng Liu Zi-Yi Li Yu-Cheng Yang fan Ping Ling-Ling Xu Wei Li Hua-Bing Zhang Yu-Xiu Li Department of Endocrinology Key Laboratory of Endocrinology of National Health CommissionPeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Endocrinology The First Affiliated Hospitaland College of Clinical Medicine of Henan University of Science and TechnologyLuoyang 471000Henan ProvinceChina

BACKGROUND Since adverse events during treatment affect adherence and subsequent glycemic control,understanding the safety profile of oral anti-diabetic drugs is imperative for type 2 diabetes mellitus(T2DM)*** To evaluate the risk of infection in patients with T2DM treated with dipeptidyl-peptidase 4(DPP-4)*** Electronic databases were *** selection criteria included randomized controlled trials focused on cardiovascular *** these studies,the effects of DPP-4 inhibitors were directly compared to those of either other active anti-diabetic treatments or *** trials involving 53616 patients were deemed *** calculated aggregate relative risks employing both random-effects and fixed-effects approaches,contingent upon the *** The application of DPP-4 inhibitors showed no significant link to the overall infection risk[0.98(0.95,1.02)]or the risk of serious infections[0.96(0.85,1.08)],additionally,no significant associations were found with opportunistic infections[0.69(0.46,1.04)],site-specific infections[respiratory infection 0.99(0.96,1.03),urinary tract infections 1.02(0.95,1.10),abdominal and gastrointestinal infections 1.02(0.83,1.25),skin structure and soft tissue infections 0.81(0.60,1.09),bone infections 0.96(0.68,1.36),and bloodstream infections 0.97(0.80,1.18)].CONCLUSION This meta-analysis of data from cardiovascular outcome trials revealed no heightened infection risk in patients undergoing DPP-4 inhibitor therapy compared to control cohorts.

关键词： T2DM drugs treatment

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硬磁软材料的磁致变形数值研究

复合材料学报 2024年第7期41卷 3831-3838页

作者：彭帆刘易函马维力长安大学理学院西安710064 长安大学材料科学与工程学院 710064

光滑有限元基于光滑应变技术,在进行数值积分时避免使用等参变换,在模拟软材料大变形问题具有一定的优势。建立了基于光滑应变技术的硬磁软材料大变形模拟的数值格式,给出了数值格式中所需要的应力张量和本构张量。采用该数值格式研究... 详细信息

光滑有限元基于光滑应变技术,在进行数值积分时避免使用等参变换,在模拟软材料大变形问题具有一定的优势。建立了基于光滑应变技术的硬磁软材料大变形模拟的数值格式,给出了数值格式中所需要的应力张量和本构张量。采用该数值格式研究了不同长高比下的硬磁软材料梁在外部磁场激励下的弯曲特性,得到的磁载荷-位移曲线和试验结果进行了对比;模拟了含有不同残余磁场方向分布的硬磁软材料结构在外磁场作用下的形态演化过程,计算的最终变形形态与试验结果进行比较。计算结果表明:采用该数值格式得到的结果与试验结果吻合较好;在不受约束的前提下,硬磁软材料内部残余磁场方向突变处变形较大。研究结果可为由硬磁软材料组成的软体机器人和智能柔性结构的力学分析与变形调控设计提供参考。

关键词：硬磁软材料光滑应变技术磁致变形有限元磁活性聚合物

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