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Deciphering the Hidden Secrets between the Early Skin Wrinkling & the Metabolic (X) Syndrome with the Possible Reversal of This Process at the Molecular Level
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作者 Dalal Alsaadoun 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第1期45-68,共24页
The aging process is a group of degenerative changes that physiologically occur in most of the people in the elderly. This affects one or more of the human body systems. The treatment of diseases related to the aging ... The aging process is a group of degenerative changes that physiologically occur in most of the people in the elderly. This affects one or more of the human body systems. The treatment of diseases related to the aging process has a huge impact on the economy of all nations. Aging of the skin comes on the top and despite that, the results of the already present lines of treatment are not always satisfactory. This acts as a stimulus for us to dig deeper to discover the root causes of the premature aging of the skin. This was simply caused by the accumulation of repeated minute damage to the internal structure skin. In other words, if the degree of minute damage is more than the capacity of the skin to repair, the repeated micro-damage is presented in the long run as a skin wrinkling. Moreover, the skin acts as a mirror that reflects the internal structures of the human body. Thus, the more degenerative changes in the human body systems, the more the skin could become wrinkled. Our strategy to prevent or at least slow down the aging process of the skin depends on 2 main steps;the 1<sup>st</sup> is to reduce the micro-damage as can as possible, and the 2<sup>nd</sup> is to enhance the capacity of tissue regeneration to be able to reverse the already present damaged skin. As the 2 processes are synchronized with each other, this strategy would be considered the ideal for prevention of skin wrinkling especially premature ones. This not only reverses premature skin wrinkling but also protects it from future wrinklings. This review sharply pointed out the role of the functional collagen of the dermal layer of the skin in the prevention of skin wrinklings. Therefore, it would be the target to study how collagen works in the complex machinery of the dermal layer of the skin. This concept deeply believes that the recovery of dermal collagen has a much better effect than simply ingesting collagen or receiving a topical collagen booster. . 展开更多
关键词 COLLAGEN Skin Wrinkling Glycation Hyper-Insulinemia hidden Obesity Vis-ceral Fat Inflammatory Cytokines
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Fresnel Equations Derived Using a Non-Local Hidden-Variable Particle Theory
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作者 Dirk J. Pons 《Journal of Modern Physics》 2024年第6期950-984,共35页
Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel... Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel equations appear not to exist. Approach: The objective of this work was to derive the basic optical laws from first principles from a particle basis. The particle model used was the Cordus theory, a type of non-local hidden-variable (NLHV) theory that predicts specific substructures to the photon and other particles. Findings: The theory explains the origin of the orthogonal electrostatic and magnetic fields, and re-derives the refraction and reflection laws including Snell’s law and critical angle, and the Fresnel equations for s and p-polarisation. These formulations are identical to those produced by electromagnetic wave theory. Contribution: The work provides a comprehensive derivation and physical explanation of the basic optical laws, which appears not to have previously been shown from a particle basis. Implications: The primary implications are for suggesting routes for the theoretical advancement of fundamental physics. The Cordus NLHV particle theory explains optical phenomena, yet it also explains other physical phenomena including some otherwise only accessible through quantum mechanics (such as the electron spin g-factor) and general relativity (including the Lorentz and relativistic Doppler). It also provides solutions for phenomena of unknown causation, such as asymmetrical baryogenesis, unification of the interactions, and reasons for nuclide stability/instability. Consequently, the implication is that NLHV theories have the potential to represent a deeper physics that may underpin and unify quantum mechanics, general relativity, and wave theory. 展开更多
关键词 Wave-Particle Duality Optical Law Fresnel Equation Non-Local hidden-Variable
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Research and Application of In-seam Seismic Survey Technology for Disaster-causing Potential Geology Anomalous Body in Coal Seam 被引量:6
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作者 TENG Jiwen LI Songying +10 位作者 JIA Mingkui LIAN Jie LIU Honglei LIU Guodong WANG Wei Volker SCHAPE FENG Lei YAO Xiaoshuai WANG Kang YAN Yafen ZHANG Wanpeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期10-26,共17页
In order to effectively detect potential geology anomalous bodies in coal bearing formation,such as coal seam thickness variation,small faults,goafs and collapse columns,and provide scientific guidance for safe and ef... In order to effectively detect potential geology anomalous bodies in coal bearing formation,such as coal seam thickness variation,small faults,goafs and collapse columns,and provide scientific guidance for safe and efficient mining,the SUMMIT-II EX explosion-proof seismic slot wave instrument,produced by German DMT Company,was used to detect the underground channel wave with the help of transmission method,reflection method and transflective method.Region area detection experiment in mining face had been carried out thanks to the advantage of channel wave,such as its great dispersion,abundant geology information,strong anti-interference ability and long-distance detecting.The experimental results showed that:(1)Coal seam thickness variation in extremely unstable coal seam has been quantitatively interpreted with an accuracy of more than 80%generally;(2)The faults,goafs and collapse columns could be detected and predicted accurately;(3)Experimental detection of gas enrichment areas,stress concentration regions and water inrush risk zone has been collated;(4)A research system of disaster-causing geology anomalous body detection by in-seam seismic survey has been built,valuable and innovative achievements have been got.Series of innovation obtained for the first time in this study indicated that it was more effective to detect disaster-causing potential geology anomalies by in-seam seismic survey than by ground seismic survey.It had significant scientific value and application prospect under complex coal seam conditions. 展开更多
关键词 in-seam seismic SURVEY technology(ISS) disaster-causing potential GEOLOGY ANOMALOUS BODY dispersion feature mine geophysical prospecting quantitative interpretation
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Switchable hidden spin polarization and negative Poisson's ratio in two-dimensional antiferroelectric wurtzite crystals
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作者 Zhuang Ma Jingwen Jiang +8 位作者 Gui Wang Peng Zhang Yiling Sun Zhengfang Qian Jiaxin Zheng Wen Xiong Fei Wang Xiuwen Zhang Pu Huang 《Journal of Semiconductors》 EI CAS CSCD 2023年第12期72-80,共9页
Two-dimensional(2D)antiferroelectric materials have raised great research interest over the last decade.Here,we reveal a type of 2D antiferroelectric(AFE)crystal where the AFE polarization direction can be switched by... Two-dimensional(2D)antiferroelectric materials have raised great research interest over the last decade.Here,we reveal a type of 2D antiferroelectric(AFE)crystal where the AFE polarization direction can be switched by a certain degree in the 2D plane.Such 2D functional materials are realized by stacking the exfoliated wurtzite(wz)monolayers with“self-healable”nature,which host strongly coupled ferroelasticity/antiferroelectricity and benign stability.The AFE candidates,i.e.,Zn X and Cd X(X=S,Se,Te),are all semiconductors with direct bandgap atΓpoint,which harbors switchable antiferroelectricity and ferroelasticity with low transition barriers,hidden spin polarization,as well as giant in-plane negative Poisson's ratio(NPR),enabling the co-tunability of hidden spin characteristics and auxetic magnitudes via AFE switching.The 2D AFE wz crystals provide a platform to probe the interplay of 2D antiferroelectricity,ferroelasticity,NPR,and spin effects,shedding new light on the rich physics and device design in wz semiconductors. 展开更多
关键词 wurtzite crystal MULTIFERROICS hidden spin polarization negative Poisson's ratio
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Existence of hidden attractors in nonlinear hydro-turbine governing systems and its stability analysis
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作者 赵鹏翀 卫皓娟 +3 位作者 徐振坤 陈帝伊 许贝贝 王雨萌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期220-228,共9页
This work studies the stability and hidden dynamics of the nonlinear hydro-turbine governing system with an output limiting link,and propose a new six-dimensional system,which exhibits some hidden attractors.The param... This work studies the stability and hidden dynamics of the nonlinear hydro-turbine governing system with an output limiting link,and propose a new six-dimensional system,which exhibits some hidden attractors.The parameter switching algorithm is used to numerically study the dynamic behaviors of the system.Moreover,it is investigated that for some parameters the system with a stable equilibrium point can generate strange hidden attractors.A self-excited attractor with the change of its parameters is also recognized.In addition,numerical simulations are carried out to analyze the dynamic behaviors of the proposed system by using the Lyapunov exponent spectra,Lyapunov dimensions,bifurcation diagrams,phase space orbits,and basins of attraction.Consequently,the findings in this work show that the basins of hidden attractors are tiny for which the standard computational procedure for localization is unavailable.These simulation results are conducive to better understanding of hidden chaotic attractors in higher-dimensional dynamical systems,and are also of great significance in revealing chaotic oscillations such as uncontrolled speed adjustment in the operation of hydropower station due to small changes of initial values. 展开更多
关键词 nonlinear hydro-turbine governing systems hidden attractors basin of attraction Lyapunov exponent spectrum
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Reliability and validity of the hidden hunger assessment scale in China-revised for high school students
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作者 Ning Zhang Minao Wang +6 位作者 Yuchen Zhang Huake Cao Yang Yang Yuhang Shi Yang Pei Feixiang Yang Yinan Du 《Global Health Journal》 2023年第2期110-116,共7页
Objective:Hidden hunger remains a severe public health problem that affects millions of people worldwide.In China,challenges related to dietary imbalance and hidden hunger persist.Micronutrient inadequacy deserves mor... Objective:Hidden hunger remains a severe public health problem that affects millions of people worldwide.In China,challenges related to dietary imbalance and hidden hunger persist.Micronutrient inadequacy deserves more attention among adolescents,given its vital role in their growth and development;however,this problem appears to have been largely ignored.High school students,in particular,are often at a high risk of hidden hunger but have limited assessment tools available.Therefore,this study aims to revise the hidden hunger assessment scale for high school students(HHAS-HSS)in China and assess its reliability and validity.Methods:Based on a literature review,expert consultation,pre-experiment,and formal survey,a hidden hunger assessment scale was revised for high school students.The formal survey involved 9336 high school students in 11 of the 16 cities in Anhui Province,China,and 9038 valid questionnaires were collected and included in the analysis.The item analysis,internal consistency reliability,test-retest reliability,content validity,exploratory factor analysis,and confirmatory factor analysis of the HHAS-HSS were examined.Results:The HHAS-HSS included a total of 4 dimensions and 12 items:"vegetables and food diversity"(three items),"fruits and dairy products"(three items),"micronutrient-dense foods"(four items),and"health condition and eating habits"(two items).The results showed a Cronbach's alpha of 0.758,a split-half reliability of 0.829,and a test-retest reliability of o.793,indicating good internal consistency.Using the Bartlett's test and Kaiser-Meyer-Olkin test(KMO)to test the exploratory factor analysis presented a four-factor model of the HHAS-HSS,the KMO0 value was 0.820(P<0.001),which indicated the possibility for factor confirmatory factor analysis.Using the maximum variance rotation method,four factors were obtained,and the cumulative variance explained rate was 57.974%.Confirmatory factor analysis also supported the division of the scale into four dimensions,and the fitting indices were x^(2)=1417.656,x^(2)/df=29.534,goodness-of-fit index=0.974,adjusted goodnessof-fit index=0.958,parsimonious goodness-of-fit index=0.600,normed fit index=0.938,incremental fit index=0.940,Tucker-Lewis index=0.917,comparative fit index=0.939,and root mean square error of approximation=0.056.Except for x^(2)/df,all the indices reached the fitting standard,and the above results showed that the construct validity of the scale reached an acceptable level.Conclusions:The HHAS-HSS has good validity and reliability for Chinese high school students.It is a convenient self-report measure of hidden hunger risk. 展开更多
关键词 hidden hunger Reliability and validity Assessment scale High school student MICRONUTRIENTS
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Application of"Six Thinking Hats"in the Investigation and Improvement of Hidden Dangers in Food Safety
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作者 Peng WAN Zhen ZHAO +3 位作者 Guoyan WEN Yunshuang FU Cuizhi LI Zhiyong LU 《Asian Agricultural Research》 2023年第10期20-22,共3页
With the development of economy,people's living standards are constantly improving,and the requirements for food safety are getting higher and higher.The Food Safety Law stipulates that enterprises should implemen... With the development of economy,people's living standards are constantly improving,and the requirements for food safety are getting higher and higher.The Food Safety Law stipulates that enterprises should implement the main responsibility of food safety,and the investigation and improvement of food safety hazards plays an important role in improving the food safety management level of enterprises and reducing food safety risks.This paper combines the innovative thinking mode of six thinking hats with food safety,discusses the application mode of six thinking hats in food safety investigation and improvement,and hopes to improve food safety level through this way. 展开更多
关键词 Six thinking hats Food safety hidden danger investigation and improvement
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Hidden Hierarchy Based on Cipher-Text Attribute Encryption for IoT Data Privacy in Cloud
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作者 Zaid Abdulsalam Ibrahim Muhammad Ilyas 《Computers, Materials & Continua》 SCIE EI 2023年第7期939-956,共18页
Most research works nowadays deal with real-time Internetof Things (IoT) data. However, with exponential data volume increases,organizations need help storing such humongous amounts of IoT data incloud storage systems... Most research works nowadays deal with real-time Internetof Things (IoT) data. However, with exponential data volume increases,organizations need help storing such humongous amounts of IoT data incloud storage systems. Moreover, such systems create security issues whileefficiently using IoT and Cloud Computing technologies. Ciphertext-Policy Attribute-Based Encryption (CP-ABE) has the potential to make IoT datamore secure and reliable in various cloud storage services. Cloud-assisted IoTssuffer from two privacy issues: access policies (public) and super polynomialdecryption times (attributed mainly to complex access structures). We havedeveloped a CP-ABE scheme in alignment with a Hidden HierarchyCiphertext-Policy Attribute-Based Encryption (HH-CP-ABE) access structure embedded within two policies, i.e., public policy and sensitive policy.In this proposed scheme, information is only revealed when the user’sinformation is satisfactory to the public policy. Furthermore, the proposedscheme applies to resource-constrained devices already contracted tasks totrusted servers (especially encryption/decryption/searching). Implementingthe method and keywords search resulted in higher access policy privacy andincreased security. The new scheme introduces superior storage in comparisonto existing systems (CP-ABE, H-CP-ABE), while also decreasing storage costsin HH-CP-ABE. Furthermore, a reduction in time for key generation canalso be noted.Moreover, the scheme proved secure, even in handling IoT datathreats in the Decisional Bilinear Diffie-Hellman (DBDH) case. 展开更多
关键词 Bilinear Diffie-Hellman(DBDH) Internet of Things(IoT) Ciphertext-Policy Attribute-Based Encryption(CP-ABE) hidden Hierarchy CP-ABE(HH-CP-ABE)
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Hidden Hearing Loss: Causes, Current Knowledge, and Future Directions
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作者 Alexandra Jalkh 《International Journal of Otolaryngology and Head & Neck Surgery》 2023年第3期107-123,共17页
Introduction: Hidden hearing loss (HHL) is a type of auditory disorder that affects the auditory neural processing and hearing sensitivity in subjects with normal hearing thresholds. Unlike central auditory processing... Introduction: Hidden hearing loss (HHL) is a type of auditory disorder that affects the auditory neural processing and hearing sensitivity in subjects with normal hearing thresholds. Unlike central auditory processing disorders, HHL happens when the cochlea (the peripheral auditory organ) is affected. There are several known risk factors to HHL which includes noise exposure, ototoxic drugs, and peripheral neuropathies, and age. Recent studies have shed light on this type of hearing loss, its etiology, prevalence, and how it can affect the auditory acuity in humans. Methods: This paper covers the current research regarding HHL, its causes, the different mechanisms involved in this disorder, and the diagnosis and potential treatments related to it. We will delve deeply into different researches concerning HHL. 4 articles from 285 were selected focusing on normal hearing individuals with bad speech intelligibility were discussed in this paper. In addition, articles discussing the effects of noise exposure on hearing impaired individuals were not considered as this study solely aims to focus on normal hearing sensitivity individuals with HHL, resulting in 4 articles from 285. Results: Numerous literatures over the decades have suggested that HHL is due to the degeneration of cochlear ribbon synapses, or hair cells synapses without hair cell damage. Their association with HHL was noted several times through this study, whether we were studying the effect of noise exposure, of age, or of ototoxicity. In all cases, no significant hair cell damage was observed, and normal thresholds were recovered. However, a decline in the amplitude of Auditory Brainstem Response (ABR) peak I from auditory nerve (AN) responses in noise exposed subjects and a decline in compound action potential (CAP) was measured when certain drugs were applied to the round window of Guinea pigs. Conclusion: Most studies, have proven that cochlear synaptophysin is the major contributor to noise induced, age, and ototoxic related HHL. There are several audiometric tests that were used to help identify HHL including Puretone audiometry in background noise, ABR, CAP, Distortion Product Otoacoustic Emission (DPOAE). 展开更多
关键词 hidden Hearing Loss Speech Testing Speech Intelligibility Noise Induced Hearing Loss OTOTOXICITY Schwan’s Cells Ablation
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隐性关联关系与审计费用——基于供应链工商大数据的研究 被引量:1
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作者 黄世忠 叶钦华 陈雪颖 《审计研究》 北大核心 2024年第2期73-86,共14页
近年来,上市公司将其供应链商业关系隐藏化以规避信息披露要求的趋势越来越明显,不利于投资者评估和判断上市公司的交易性质和盈利能力。本文从审计师角度出发,以2010-2021年度我国A股上市公司为研究对象,基于供应链工商大数据度量隐性... 近年来,上市公司将其供应链商业关系隐藏化以规避信息披露要求的趋势越来越明显,不利于投资者评估和判断上市公司的交易性质和盈利能力。本文从审计师角度出发,以2010-2021年度我国A股上市公司为研究对象,基于供应链工商大数据度量隐性关联关系,分析隐性关联关系与审计费用之间的关系,结果发现上市公司与重要交易对象之间存在隐性关联关系提高了审计费用,一系列稳健性检验结果保持一致。在渠道检验中,研究发现隐性关联关系通过影响审计师投入,进一步影响审计费用。在分组检验中,研究发现隐性关联关系对审计费用的影响在高市场化进程地区、低信息透明度的公司以及当上市公司为事务所重要客户时更为显著。本文研究为审计师如何判断隐性关联关系问题提供了经验数据。 展开更多
关键词 隐性关联关系 审计费用 信息披露 审计投入 风险补偿
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虚拟社区激励措施对用户知识贡献倾向的影响机理研究
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作者 张红超 王茜 容哲 《管理学报》 北大核心 2024年第3期427-434,444,共9页
基于SOR理论和隐马尔科夫模型,采用马蜂窝旅游虚拟社区用户知识贡献行为数据和激励数据,探讨外在激励如何通过用户知识贡献倾向影响其知识贡献行为。研究表明:依据构建的隐马尔科夫模型,挖掘用户具有沉默、参与、积极3种隐含的知识贡献... 基于SOR理论和隐马尔科夫模型,采用马蜂窝旅游虚拟社区用户知识贡献行为数据和激励数据,探讨外在激励如何通过用户知识贡献倾向影响其知识贡献行为。研究表明:依据构建的隐马尔科夫模型,挖掘用户具有沉默、参与、积极3种隐含的知识贡献倾向;同一知识贡献倾向下,用户首次回答问题时间越早、旅游经验越丰富、累计贡献数量越多,用户知识贡献数量就越多;物质激励、精神激励以及二者联合激励与用户动态变化知识贡献倾向匹配,才能取得正向的激励作用。 展开更多
关键词 知识贡献倾向 激励措施 隐含倾向 隐马尔科夫模型
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一种非常规“暗链”的清除探索
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作者 邓卫红 刘伟跃 《科技资讯》 2024年第11期55-58,共4页
网页被植入暗链是企事业网站、教育类网站上常见的攻击行为,攻击手法变化多样,往往不容易被轻易检测出来。笔者遇到了一种非常规的暗链,它并没有在网页中直接植入隐蔽的链接代码,并且该暗链无法在电脑端访问,只能在手机端打开。通过分... 网页被植入暗链是企事业网站、教育类网站上常见的攻击行为,攻击手法变化多样,往往不容易被轻易检测出来。笔者遇到了一种非常规的暗链,它并没有在网页中直接植入隐蔽的链接代码,并且该暗链无法在电脑端访问,只能在手机端打开。通过分析攻击路径、木马特点、IIS日志、暗链来源等一系列的排查和探索,终于找到了暗链实现挂网的操作流程并对其进行了清除。 展开更多
关键词 暗链 攻击路径 木马检测 服务器
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隐性听力损失中医病机及防治研究进展
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作者 曲中源 石磊 +1 位作者 冷辉 孙海波 《中华中医药学刊》 CAS 北大核心 2024年第2期46-50,共5页
隐性听力损失是以纯音听阈正常,噪声背景下言语识别能力降低为主要症状的疾病,噪声暴露、药物损伤、年龄老化是主要的致病危险因素,其发病隐匿,容易忽视,危险因素持续暴露可造成不可逆听力损伤,目前临床多无有效的治疗方法,以早期预防... 隐性听力损失是以纯音听阈正常,噪声背景下言语识别能力降低为主要症状的疾病,噪声暴露、药物损伤、年龄老化是主要的致病危险因素,其发病隐匿,容易忽视,危险因素持续暴露可造成不可逆听力损伤,目前临床多无有效的治疗方法,以早期预防为主。根据隐性听力损失的致病因素及发病机制,探讨隐性听力损失的中医病机,认为脾虚湿滞、清窍蒙蔽、肾元不足、邪聚耳窍为致病的内在因素,毒邪犯耳、内毒留滞、毒瘀经络为病理机制,并对近年来隐性听力损失的预防与治疗研究概况做一总结,为中医药治疗隐性听力损失研究提供理论依据和临床经验。 展开更多
关键词 隐性听力损失 病机 中医疗法 研究进展
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北京延庆泥石流隐患分布规律及演化趋势研究
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作者 王瑞军 王帅东 +3 位作者 孙永彬 王诜 张春雷 王永军 《世界核地质科学》 CAS 2024年第3期623-632,共10页
泥石流是一种具有强烈破坏性的山区突发性地质灾害现象,是北京山区较严重、危害性较大的地质灾害类型之一。北京延庆泥石流灾害的研究主要针对局部或单流域泥石流沟,区域性的泥石流隐患特征、分布规律以及演化特征等研究工作极少。以北... 泥石流是一种具有强烈破坏性的山区突发性地质灾害现象,是北京山区较严重、危害性较大的地质灾害类型之一。北京延庆泥石流灾害的研究主要针对局部或单流域泥石流沟,区域性的泥石流隐患特征、分布规律以及演化特征等研究工作极少。以北京延庆泥石流隐患为研究对象,旨在为延庆山区泥石流灾害预警预报和防灾减灾提供理论依据。通过收集延庆泥石流隐患相关文献资料,实际调查泥石流隐患发育特征,系统分析延庆泥石流灾害的孕灾背景情况,梳理自然地理、地质背景及人类活动之间的内在联系,查明泥石流隐患的沟域和物源特征,研究泥石流隐患所在流域的地貌形态、地形坡度、降雨条件及地层岩性的分布特征,探究泥石流、水石流和发育期、衰退期泥石流隐患的物源分布规律,查清泥石流隐患的物源转化过程,掌握延庆主要处于发育期和衰退期的泥石流隐患演化趋势。研究结果表明:延庆泥石流隐患属于暴雨型-沟谷型-支沟群发型泥石流,泥石流规模大小与流域地形地貌、松散堆积物累积、动态变化以及暴雨情况相关,研究成果可为泥石流调查研究、预测预报和监测预警提供科学依据和技术参考。 展开更多
关键词 泥石流 分布规律 地质灾害 延庆
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延长氨甲环酸使用时间有助于减少老年股骨转子间骨折围术期隐性失血
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作者 赵燕 吴凡 +4 位作者 李红 万盛钰 何瑾 朱宾仁 江从兵 《中国组织工程研究》 CAS 北大核心 2024年第36期5858-5864,共7页
背景:股骨转子间骨折好发于老年人,手术后会出现大量的隐性失血,减少隐性失血可以降低并发症和住院时间。目的:评估延长氨甲环酸的使用时间对股骨近端防旋髓内钉治疗转子间骨折围术期隐性失血的影响。方法:选择2022年1月至2023年5月自... 背景:股骨转子间骨折好发于老年人,手术后会出现大量的隐性失血,减少隐性失血可以降低并发症和住院时间。目的:评估延长氨甲环酸的使用时间对股骨近端防旋髓内钉治疗转子间骨折围术期隐性失血的影响。方法:选择2022年1月至2023年5月自贡市第四人民医院经急诊收治入院的老年股骨转子间骨折患者共62例,均在牵引床上闭合牵引复位后置入股骨近端防旋髓内钉治疗。根据氨甲环酸的使用时间分为2组,对照组38例在切开皮肤前15-30 min给予氨甲环酸1 g静脉滴注,3 h后追加1 g;试验组24例在对照组的基础上,术后第1天再追加氨甲环酸1 g静脉滴注每12 h一次。术前、术后当天、术后第1,3,5天均复查血常规,统计血红蛋白量和红细胞压积,理论总失血量采用Gross方程计算,同时记录两组患者并发症发生情况。结果与结论:①通过统计学分析,两组患者术中显性出血量相差较小,差异无显著性意义(P>0.05);②试验组围术期血红蛋白下降量、总失血量、隐性失血量低于对照组,差异有显著性意义(P<0.05);③试验组术后第3天的血红蛋白值、术后第1,3天的红细胞压积值高于对照组,差异有显著性意义(P<0.05);④两组术后血红蛋白和血小板计数呈下降趋势,第3天的血红蛋白值为最低值,术后第1天的血小板值为最低值,然后开始回升;⑤两组患者术后并发症发生率相比差异无显著性意义(P>0.05);⑥结果表明,术后延迟氨甲环酸的使用时间,可能有助于减少股骨近端防旋髓内钉治疗股骨转子间骨折的隐性失血量,并不会增加并发症风险。 展开更多
关键词 氨甲环酸 股骨转子间骨折 股骨近端防旋髓内钉 隐性失血 血红蛋白 血小板计数
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基于震源机制和地震定位研究2022年山西古交M_(L)4.1地震的发震构造
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作者 董春丽 张广伟 +3 位作者 李欣蔚 王跃杰 丁大业 宫卓宏 《地震地质》 EI CSCD 北大核心 2024年第2期414-432,共19页
2022年2月20日山西太原古交市发生了M_(L)4.1地震,古交及周边县市震感强烈。此次地震的震中位于历史地震相对稀少、煤矿资源丰富的吕梁隆起区,其发震断裂尚不明确。为了更好地认识这次地震的发震构造,文中利用山西省测震台网的近震波形... 2022年2月20日山西太原古交市发生了M_(L)4.1地震,古交及周边县市震感强烈。此次地震的震中位于历史地震相对稀少、煤矿资源丰富的吕梁隆起区,其发震断裂尚不明确。为了更好地认识这次地震的发震构造,文中利用山西省测震台网的近震波形资料反演了地震的震源机制解,并获得最佳矩心深度。反演结果显示,古交地震是一次左旋走滑型地震事件,矩震级为M_(W)3.96,最佳双力偶解为:节面Ⅰ,走向90°、倾角86°、滑动角-19°;节面Ⅱ,走向182°、倾角70°、滑动角-175°;最佳矩心深度为3km,属于极浅源地震。地震序列重定位结果显示震中的优势展布方向近EW,与区域内断层基本为NE走向的分布格局差异显著。利用聚类分析方法得到古交地震的发震断层面中心解,结果显示断层的走向为91°,倾角为70°。另外,古交地震序列的应力降显著偏小,低于同区域背景地震至少1个数量级。结合实地调研的矿区生产情况和区域地质构造,认为古交地震序列的发震机制可能与震源区附近的煤田开采活动有关,开采活动致使局部应力改变,从而导致先存隐伏断层活化,进而触发此次地震。 展开更多
关键词 古交地震 震源机制解 隐伏断层 gCAP方法 地震应力降
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小尺度山区地质灾害隐患的无人机精细化识别方法与实践
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作者 黄海峰 张瑞 +6 位作者 周红 易武 薛蓉花 董志鸿 柳青 邓永煌 张国栋 《测绘通报》 CSCD 北大核心 2024年第1期6-11,共6页
本文针对小空间尺度范围内以滑坡、崩塌为主的山区地质灾害,提出了一套基于小型无人机摄影测量的精细化隐患识别方法。首先,针对工作区开展至少两期无人机摄影测量作业,经处理后得到实景三维模型、数字正射影像(DOM)、数字表面模型(DSM... 本文针对小空间尺度范围内以滑坡、崩塌为主的山区地质灾害,提出了一套基于小型无人机摄影测量的精细化隐患识别方法。首先,针对工作区开展至少两期无人机摄影测量作业,经处理后得到实景三维模型、数字正射影像(DOM)、数字表面模型(DSM)等精细化成果;其次,以两期DOM与DSM变化检测为主实现灾害体识别;然后,基于灾害体共性特征建立典型识别标志,并依此采用三维实景目视解译为主方法实现孕灾体识别;最后,通过地面核查确认或排除隐患。将该套方法应用到三峡库首秭归泄滩河左岸顺向斜坡区域,共识别出10处不同类型隐患,证明了方法的可行性。 展开更多
关键词 山区地质灾害 隐患识别 孕灾特征 无人机 变化检测
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基于GRA-ISM-HMM的广州市肉及肉制品安全风险评估
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作者 张维蔚 陈坤才 +2 位作者 张玉华 陈燕珊 黄德演 《现代食品科技》 CAS 北大核心 2024年第4期312-320,共9页
该研究旨在利用广州食品安全风险监测2015年至2020年针对肉及肉制品样本的检测数据,构建肉及肉制品的安全风险评估模型,从而了解广州市该段时间内肉及肉制品的食品安全风险及其时变特点。该研究采取灰色关联分析方法和解释结构模型建立... 该研究旨在利用广州食品安全风险监测2015年至2020年针对肉及肉制品样本的检测数据,构建肉及肉制品的安全风险评估模型,从而了解广州市该段时间内肉及肉制品的食品安全风险及其时变特点。该研究采取灰色关联分析方法和解释结构模型建立风险指数,并基于该指标值作为隐马尔可夫模型的观测值探讨观测背后的隐含风险状态。分析结果显示,2015~2020年所有样本综合风险指数结果都在[0,0.45]之间,总体风险都较小,其中2019年风险最高;将风险指数进行等级划分,显示2015~2020年风险等级为[1,2,2,2,3,1];通过HMM分析得到这六年的隐藏风险等级为[0,1,1,1,2,0],与观测风险结果一致,且HMM预测2021年风险等级为1,即表明广州肉及肉制品风险往良好态势发展。最后,进行风险差异原因分析,发现各肉制品分类之间有差异,其中腊肠、鸡肉和腊肉的风险指数较高于其他种类,而2019年增加腊肠和腊肉的检测是风险增加的一个原因。总体来说,广州肉及肉制品风险较小,但依旧需要监督改善。 展开更多
关键词 肉及肉制品 风险评估 灰色关联分析 解释结构模型 隐马尔夫模型
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“隐变量理论”是特设性假说吗——兼论“可检验性”标准
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作者 张卫 马晓天 《长沙理工大学学报(社会科学版)》 2024年第2期26-32,共7页
从EPR佯谬理论的提出到贝尔不等式的实验检验,“隐变量理论”实现了从形而上学之争到可检验的科学理论的转变。“隐变量理论”的历史嬗变表明,假说的“可检验性”并非一成不变,而是随着历史条件的改变而发生变化。这意味着把“可检验性... 从EPR佯谬理论的提出到贝尔不等式的实验检验,“隐变量理论”实现了从形而上学之争到可检验的科学理论的转变。“隐变量理论”的历史嬗变表明,假说的“可检验性”并非一成不变,而是随着历史条件的改变而发生变化。这意味着把“可检验性”当成一个纯粹的分析性概念是有问题的,“可检验性”也是一个兼具分析性和综合性的范畴。为了使“可检验性”标准能够更好地解释真实的科学历史,需要摆脱传统的分析性理解,以一种历史的眼光重新理解“可检验性”。 展开更多
关键词 可检验性 隐变量理论 形而上学
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基于隐结构模型结合关联规则研究冠心病稳定型心绞痛中医证候特征
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作者 王雪 张明雪 《辽宁中医杂志》 CAS 北大核心 2024年第4期1-6,I0001,共7页
目的探讨冠心病稳定型心绞痛中医证候的分布及特征,为今后冠心病稳定型心绞痛的辨证论治提供客观可靠的依据。方法计算机检索中国期刊全文数据库(CNKI)、万方(WanFang)、维普(VIP)等数据库内自建库以来至2022年1月的名老中医治疗冠心病... 目的探讨冠心病稳定型心绞痛中医证候的分布及特征,为今后冠心病稳定型心绞痛的辨证论治提供客观可靠的依据。方法计算机检索中国期刊全文数据库(CNKI)、万方(WanFang)、维普(VIP)等数据库内自建库以来至2022年1月的名老中医治疗冠心病稳定型心绞痛的医案及临床经验,采用孔明灯Lantern5.0软件,应用爬山法(LTM-EAST)算法建立症状隐结构模型并进行综合聚类分析;采用SPSS Modeler 15.1软件,用Apriori算法,对中医证素进行关联规则分析并绘制复杂网络图。结果①纳入的206例医案共涉及24个中医证候,其中频次较高(>5%)的分别为心血瘀阻证、痰瘀互结证、气滞血瘀证、痰湿阻滞证、气虚血瘀证、心阳虚证、气阴两虚证。②将共计121个症状作为显变量,应用LTM-EAST算法构建结构模型,得出30个隐变量,对得出的30个隐变量进行综合聚类,共得出9个综合聚类模型即9个中医证候,分别为气滞血瘀证、心血瘀阻证、气虚血瘀证、心阳虚证、气阴两虚证、痰瘀互结证、痰湿内阻证、痰热内闭证、心肾阳虚证。③对24个中医证候提取的17个证素进行关联规则分析,推导出7个中医证候,分别为心血瘀阻证、心阳虚衰证、痰瘀互结证、气阴两虚证、阳虚血瘀证、气虚血瘀证、气滞血瘀证。结论综合归纳,最终得出6个中医常见证候,分别为:气滞血瘀证、心血瘀阻证、气虚血瘀证、心阳虚证、气阴两虚证、痰瘀互结证。 展开更多
关键词 隐结构模型 关联规则 冠心病稳定型心绞痛 中医证候
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