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Nano-scale Reinforcements and Properties of Al-Si-Cu Alloy Processed by High-Pressure Torsion

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1253-1259页

作者： DONG Ying WU Siyuan HE Ziyang LIANG chen chenG Feng HE Zuwei QIAN chenhao School of Mechanical Engineering Jiangnan UniversityWuxi 214122China Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology Wuxi 214122China School of International Studies Renmin University of ChinaBeijing 100872China School of Engineering University of LiverpoolLiverpool L693GHUnited Kingdom

To improve the comprehensive mechanical properties of Al-Si-Cu alloy,it was treated by a high-pressure torsion process,and the effect of the deformation degree on the microstructure and properties of the Al-Si-Cu alloy was *** results show that the reinforcements(β-Si andθ-CuAl_(2)phases)of the Al-Si-Cu alloy are dispersed in theα-Al matrix phase with finer phase size after the *** processed samples exhibit grain sizes in the submicron or even nanometer range,which effectively improves the mechanical properties of the *** hardness and strength of the deformed alloy are both significantly raised to 268 HV and 390.04 MPa by 10 turns HPT process,and the fracture morphology shows that the material gradually transits from brittle to plastic before and after *** elements interdiffusion at the interface between the phases has also been effectively *** addition,it is found that the severe plastic deformation at room temperature induces a ternary eutectic reaction,resulting in the formation of ternary Al+Si+CuAl_(2)eutectic.

关键词： Al-Si-Cu alloy high-pressure torsion nano-scale reinforcements ternary eutectic

Flowering-time regulation by the circadian clock:From Arabidopsis to crops

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The Crop Journal 2024年第1期12卷 17-27页

作者： Mingkang Yang Wenjie Lin Yarou Xu Biyu Xie Baiyin Yu Liang chen Wei Huang State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources College of Life SciencesSouth China Agricultural UniversityGuangzhou 510642GuangdongChina Henry Fok School of Biology&Agriculture Shaoguan UniversityShaoguan 512005GuangdongChina Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms South China Agricultural UniversityGuangzhou 510642GuangdongChina Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642GuangdongChina Guangdong Provincial Key Laboratory of Utilization and Conservation of Food and Medicinal Resources in Northern Region Shaoguan UniversityShaoguan 512005GuangdongChina

Precise timing of flowering in plants is critical for their growth and reproductive *** factor controlling flowering time is the cycle of light and darkness within a day,known as the *** are classified into long-day,short-day,and day-neutral plants based on light requirements for floral *** the molecular mechanisms that govern this differentiation remain incompletely understood,studies have consistently shown that the circadian clock plays a central role in regulating photoperiod response across diverse plant ***,there is a scarcity of reviews describing the regulatory network linking the circadian clock with photoperiodic *** review summarizes that regulatory network,focusing on the distinct roles of clock genes in long-day and short-day *** also discuss the strategies of clock gene mutations contributing to geographic variation in longday and short-day crops.

关键词： Circadian clock Photoperiod Short-day plants Long-day plants

Excessive level of dietary insect protein negatively changed growth metabolomic and transcriptomic profiles of largemouth bass(Micropterus salmoides)

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Animal Nutrition 2024年第2期17卷 397-407页

作者： Hao Sun Wenjing Dong Guanglun He Yong Long Yuanfa He Yongjun chen shimei Lin College of Fisheries Southwest University College of Fisheries Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education) Southwest University State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences

Hermetia illucens(HI) meal is a promising substitute for fish meal(FM) in the feeds of farmed ***, the impacts of dietary HI meal on largemouth bass(LMB) remain unknown. In this study, we formulated three isonitrogenous and isolipid diets with 0%(HI0, control), 20%(HI20) and 40%(HI40) of FM substituted by HI meal. A total of 270 juvenile largemouth bass with an initial body weight of10.02 ± 0.03 g were used(30 fish per tank). After an 80-day feeding trial, the fish fed with the HI40 diet demonstrated decreased growth performance and protein efficiency ratio(PER), and increased liver oxidative indices and lipid accumulation compared to the control(P < 0.05). Transcriptomic analysis revealed the effects of high dietary HI meal on liver gene expression. Consistent with the reduced growth and disturbed liver oxidative status, the upregulated genes were enriched in the biological processes associated with protein catabolism and endoplasmic reticulum(ER) stress; while the downregulated genes were enriched in cellular proliferation, growth, metabolism, immunity and maintenance of tissue homeostasis. Differential metabolites in the liver samples were also identified by untargeted metabolomic assay. The results of joint transcriptomic-metabolomic analyses revealed that the pathways such as one carbon pool by folate, propanoate metabolism and alpha-linolenic acid metabolism were disturbed by high dietary HI meal. In summary, our data revealed the candidate genes, metabolites and biological pathways that account for the adverse effects of high HI meal diet on the growth and health of LMB.

关键词： Hermetia illucens Growth Transcriptome Metabolomic effect Micropterus salmoides

局部安全系数引入下岩质边坡稳定性分析极限平衡滑面应力法

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岩石力学与工程学报 2024年第4期43卷 964-985页

作者：邓东平彭一航陈浩宇王翊民中南大学土木工程学院湖南长沙400075

由于广义非线性Hoek-Brown(H-B)强度准则可展现出岩体的复杂剪切破坏行为,因此,其被广泛地应用于岩质边坡稳定性分析。然而,以条块划分与条间力假设模式而建立的传统极限平衡方法不易于直接引入非线性强度准则,使得极限平衡方法在分析... 详细信息

由于广义非线性Hoek-Brown(H-B)强度准则可展现出岩体的复杂剪切破坏行为,因此,其被广泛地应用于岩质边坡稳定性分析。然而,以条块划分与条间力假设模式而建立的传统极限平衡方法不易于直接引入非线性强度准则,使得极限平衡方法在分析岩质边坡稳定性方面存在些许不足。此外,边坡稳定性分析时,以往常将滑面局部安全系数假定为与位置无关的单一变量。事实上,边坡在未达到临界失效状态前,滑面局部安全系数分布存在差异性。为此,应用Taylor级数展开式构建滑面正应力函数,并考虑滑面局部安全系数差异性,建立滑面局部安全系数倒数线性分布特征下滑面剪应力函数。进而,实现滑面应力计算模式与滑面局部安全系数差异分布特征下广义非线性H-B强度准则的融入。随后,引入滑面端部应力约束条件,并依据边坡滑体所满足的整体力学平衡方程,推导出岩质边坡稳定性极限平衡解答。通过算例对比分析,可知本文方法不仅可准确地评估出非线性强度准则下岩质边坡稳定性,而且能够合理地模拟出近坡顶处滑面拉剪应力区、客观地描述出应力集中效应下近坡脚处滑面压剪现象以及有效地判别出滑面局部安全系数差异分布特征。进一步,为了便于指导工程岩质边坡设计与加固,绘制了均质岩石边坡最小安全系数等值曲线图与临界滑面局部安全系数差异分布特征分区图。

关键词：边坡工程广义非线性H-B强度准则岩质边坡稳定性极限平衡滑面应力滑面局部安全系数滑面端部应力约束条件

新型耗能连接正交胶合木剪力墙抗侧力性能试验

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同济大学学报（自然科学版） 2024年第5期52卷 697-706页

作者：陈佳炜熊海贝彭增鑫王瑞明南京林业大学土木工程学院江苏南京210037 同济大学土木工程学院上海200092 联领建筑科技(上海)有限公司上海202172

为研究基于软钢屈服与橡胶剪切变形双重耗能机制新型连接的正交胶合木剪力墙抗侧力性能,考虑顶部竖向荷载、墙体高宽比、耗能连接件可更换性等因素,对6榀2.4m高足尺试件进行了单调及低周往复加载试验,并与普通金属连接正交胶合木墙体进... 详细信息

为研究基于软钢屈服与橡胶剪切变形双重耗能机制新型连接的正交胶合木剪力墙抗侧力性能,考虑顶部竖向荷载、墙体高宽比、耗能连接件可更换性等因素,对6榀2.4m高足尺试件进行了单调及低周往复加载试验,并与普通金属连接正交胶合木墙体进行对比试验,获取并分析了剪力墙的破坏过程、力学性能参数及各项因素对抗侧力性能的影响规律。结果表明:新型耗能连接正交胶合木剪力墙在侧向力下的损伤主要集中在耗能连接的软钢耗能段屈服断裂与耗能橡胶脱胶破坏,墙体板材与自攻螺钉未见损伤;增大顶部竖向荷载可有效提升墙体的抗侧力性能,而增大高宽比主要可增加墙体的变形能力与延性;与普通金属连接墙体相比,耗能连接墙体的最大承载力相近,但延性提升26%,耗能能力提升38%,最大层间位移角可达1/23,且在原位替换耗能连接修复的墙体与原墙体的抗侧力性能相近,表明新型耗能连接正交胶合木剪力墙具有较好抗震性能,可实现强震后连接可更换、结构可修复的设计目标。

关键词：正交胶合木剪力墙结构新型耗能连接抗侧力性能破坏模式

A survey of ictal physical examination during VEEG monitoring in a tertiary epilepsy center

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Acta Epileptologica 2024年第2期7卷 130-136页

作者： Yinping Li Xiaoying Hu Shufang Zhang Jiani chen Department of Neurology West China School of NursingSichuan University/West China HospitalSichuan UniversityChengdu 610041China Department of Neurology West China HospitalSichuan UniversityNo.37 Guoxue RoadChengdu 610041China

Background Ictal examination based on video-based electroencephalography(EEG)is crucial for locating and lat-eralizing *** this study,we aimed to evaluate the quality of ictal examination in the Comprehensive Epilepsy Center of West China Hospital,Sichuan University,in order to provide information for quality improvement in daily clinical *** Video recordings of 100 patients with epilepsy were retrospectively *** performance of the ictal examination was independently reviewed by two epileptologists using an ictal examination *** In this retrospective analysis,589 seizure episodes from 100 patients with epilepsy were *** ages of the patients ranged from 3 to 77 years,with a mean age of 25.8±12.8 *** the 589 seizure episodes,a majority(93.7%)were focal *** 226(38.4%)seizures,the medical staff arrived at the *** them,153(153/226,64.7%)seizure episodes,the medical staff arrival at the bedside within 30 s of onset,and 120(120/226,53.1%)seizures were tested by the medical *** compliance rates for"safety"and"visibility"reached 80%or higher while"naming","retelling",and“memory testing”only reach less than 3%.Conclusions Our survey identified the main problems in ictal *** is challenging to complete a standard-ized examination for new trainees at Epilepsy Monitoring *** strengthening training in ictal examination and understanding of semiology may improve patients’examination ***,further study of the implemen-tation of training is necessary.

关键词： Epilepsy Ictal examination Video EEG

Structural basis for polyuridine tract recognition by SARS-CoV-2 Nsp15

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Protein & Cell 2024年第7期15卷 547-552页

作者： Fumiaki Ito Hanjing Yang Z.Hong Zhou Xiaojiang S.chen Molecular and Computational Biology Department of Biological SciencesUniversity of Southern CaliforniaLos AngelesCA 90089United States Department of Microbiology Immunology and Molecular GeneticsUniversity of CaliforniaLos AngelesCA 90095United States California NanoSystems Institute University of CaliforniaLos AngelesCA90095United States Genetic Molecular and Cellular Biology ProgramKeck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90089United States Norris Comprehensive Cancer Center University of Southern CaliforniaLos AngelesCA 90089United States Center of Excellence in NanoBiophysics University of Southern CaliforniaLos AngelesCA 90089United States

Dear Editor,Coronaviruses have evolved a wide array of tactics to evade host antiviral *** host cells detect invading foreign nucleic acids including viral genome and viral replication intermediates,they activate interferon(IFN)signaling via cytoplasmic pattern recognition receptors(Kang et al.,2002;Kato et al.,2006).Remarkable stealth activities exhibited by coronaviruses are facilitated by a series of non-structural proteins(Nsps),such as Nsp15(Deng and Baker,2018;Deng et al.,2019;Hackbart et al.,2020),which is a uridine-specific endoribonuclease that mediates evasion of host detection of viral double-stranded RNA(dsRNA)(Bhardwaj et al.,2004;Deng et al.,2017;Frazier et al.,2021;Ivanov et al.,2004).Nsp15 targets a polyuridine[poly(U)]tract on the coronavirus negative strand RNA(Hackbart et al.,2020).Nsp15 limits the abundance and length of poly(U)within the negative strand RNA 5ʹ-extension by trimming down the initially synthesized poly(U)lead sequence to the optimal length that can suppress dsRNA formation but still serves as a template for poly(A)tail of the positive strand genome of the coronaviruses(Hofmann and Brian,1991).

关键词： p15 interferon template

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基于宽度自编码网络的单分类集成算法

信号处理 2024年第4期40卷 776-788页

作者：施一帆陈宇昂曾焕强杨楷翔华侨大学工学院福建泉州362021 华南理工大学计算机科学与工程学院广东广州510006 计算机软件新技术国家重点实验室江苏南京210023

异常检测是模式识别领域的经典研究,然而在极端类别不平衡场景下,异常样本匮乏,训练数据仅包含正常样本,传统异常检测方法难以适用。因此,单分类算法逐渐受到关注,它只使用目标类样本构建决策边界,实现对非目标类样本的识别。目前单分... 详细信息

异常检测是模式识别领域的经典研究,然而在极端类别不平衡场景下,异常样本匮乏,训练数据仅包含正常样本,传统异常检测方法难以适用。因此,单分类算法逐渐受到关注,它只使用目标类样本构建决策边界,实现对非目标类样本的识别。目前单分类算法已经取得了显著进展,然而也存在一些局限性:(1)原始特征空间容易受噪声特征干扰;(2)单模型的单分类算法难以从多个特征空间学习更全面的决策边界;(3)缺少对先前模型的欠拟合样本进行针对性学习。为了解决这些问题,本文提出了基于宽度自编码网络的单分类集成算法(Ensemble One-class Classification Based on BLS-Autoencoder,EOC-BLSAE)。首先,本文设计了一种单分类宽度自编码网络模型(One-class BLS-Autoencoder,OC-BLSAE),它能高效学习原始特征空间到重构特征空间的非线性映射关系,利用重构误差构建决策边界;接着,本文设计了单分类Boosting策略,通过最小化全局重构损失,迭代学习欠拟合样本,从而多角度构建OC-BLSAE模型,并自适应评估模型的可靠性;最终,加权集成多个OC-BLSAE模型,有效提升整体算法准确性和鲁棒性。在实验中,本文在16个不同规模的单分类任务上进行参数实验、对比实验和消融实验,结果表明所提算法参数选择较为灵活,算法各模块能够相互协同,有效提升单分类任务的准确性和鲁棒性,整体性能超过前沿单分类方法。

关键词：单分类异常检测宽度学习系统集成学习

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青海磨石沟地区锰矿地质特征及成因探讨

西北地质 2024年第2期57卷 135-145页

作者：彭涛才永吉张国鹏陈健青海省有色第一地质勘查院青海西宁810000 青海省隐伏矿勘查重点实验室青海西宁810000

青海磨石沟锰矿是近年来东昆仑南坡地区新发现的台盆相沉积型碳酸锰矿,主要赋存于中新元古界万宝沟群碳酸盐岩组顶部。含锰岩系及锰矿体具有厚度大、延伸稳定、岩性组合简单及整体品位偏低但储量较大的特点,是青海省内少数具有良好前景... 详细信息

青海磨石沟锰矿是近年来东昆仑南坡地区新发现的台盆相沉积型碳酸锰矿,主要赋存于中新元古界万宝沟群碳酸盐岩组顶部。含锰岩系及锰矿体具有厚度大、延伸稳定、岩性组合简单及整体品位偏低但储量较大的特点,是青海省内少数具有良好前景的锰矿勘查基地之一。根据磨石沟锰矿区的最新勘查成果,从成矿地质背景、矿区地质特征、厚大的白云岩–碳质板岩含锰岩系、层状密集分布的锰矿体、矿石质量特征及主–微量元素特征等方面推断矿床成因与热水沉积关系密切,初步探究磨石沟地区热水沉积锰矿的成矿模式。通过综合分析,初步评价磨石沟锰矿区的找矿潜力,为类似沉积型锰矿勘查提供找矿借鉴。

关键词：青海沉积型碳酸锰矿地质特征矿床成因成矿模式找矿潜力