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A novel mind-set in primate experimentation:Implications for primate welfare 被引量:1
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作者 Antonella Tramacere Atsushi Iriki 《Animal Models and Experimental Medicine》 CSCD 2021年第4期343-350,共8页
We emphasize the importance of studying the primate brain in cognitive neuroscience and suggest a new mind-set in primate experimentation within the boundaries of animal welfare regulations.Specifically,we list the ad... We emphasize the importance of studying the primate brain in cognitive neuroscience and suggest a new mind-set in primate experimentation within the boundaries of animal welfare regulations.Specifically,we list the advantages of investigating both genes and neural mechanisms and processes in the emergence of behavioral and cognitive functions,and propose the establishment of an open field of primate research.The latter may be conducted by implementing and harmonizing experimental practices with ethical guidelines that regulate(1)management of natural parks with free-moving populations of target nonhuman primates,(2)establishment of indoor-outdoor labs for both system genetics and neuroscience investigations,and(3)hotel space and technologies which remotely collect and dislocate information regarding primates geographically located elsewhere. 展开更多
关键词 animal models cognitive neuroscience natural parks NEUROPSYCHIATRY primate experimentation primate welfare Research Domain Criteria
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Diversified Teaching Methods in Nursing:Using Animal Experimentation to Promote Core Professional Competencies in Basic Nursing Training 被引量:1
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作者 Hui Lin Wei Wang Yin-Jun Ye 《Chinese Nursing Research》 CAS 2015年第4期155-159,共5页
Objective: The aim of this project was to train highly professional and specialized nursing students from medical colleges to adapt to bedside clinical care by exploring and discussing various methods of injection an... Objective: The aim of this project was to train highly professional and specialized nursing students from medical colleges to adapt to bedside clinical care by exploring and discussing various methods of injection and IV infusion in animal experimentation to hone the core professional nursing competencies. Methods: Two classes from the 2012 senior graduating nursing class were randomly selected by a computer to conduct the diversified practical teaching methods based on animal experimentation. A hospital environment was simulated by requiring students to perform different types of injections and practical IV infusion techniques. A comprehensive evaluation of the core professional competencies, as well as other integrated competencies, was conducted to determine the effectiveness of the teaching methods. Results: Two-sampled, pairwise u-tests were performed between the scores of the experimental (nursing class 2) and control (nursing class 1) groups. These findings showed that the overall test scores were significantly higher in the experimental group compared to the control group and that the average P-values for the competencies in various categories were 〈0.01, which indicated statistically significant results. Conclusions: Based on the data from this project, diversified teaching methods for basic nursing training founded on animal experimentation can help nursing students perfect their core professional competencies and improve their overall professional standing. The introduction of animal experimentation requires further verification, and an increased acknowledgement of its benefits through the widespread dissemination of this information. 展开更多
关键词 Core professional competencies Basic nursing experimentation on animals Diversified teaching methods
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Estimation of Minimum Miscibility Pressure for Flue Gas Injection Using Soft Experimentations 被引量:1
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作者 Oluwaseun Oyinloye Naeema Al Darmaki +2 位作者 Mohamed Al Zarooni Fathi Boukadi Hildah Nantongo 《Natural Resources》 2021年第11期363-381,共19页
A new approach is demonstrated in which soft experimentation can be performed for MMP measurements, thus replacing the common practice of slim tube displacement laboratory experiments. Recovery potential from oil rese... A new approach is demonstrated in which soft experimentation can be performed for MMP measurements, thus replacing the common practice of slim tube displacement laboratory experiments. Recovery potential from oil reservoirs by miscible flue gas injection was studied by slim tube and field-scale numerical simulation using two flue gases and seven crude oils sampled at different depths in three candidate reservoirs. The soft experimentations were conducted using Eclipse300<sup>TM</sup>, a three-phase compositional simulator. This study investigates minimum miscibility pressure (MMP), a significant miscible gas injection project screening tool. Successful design of the project is contingent to the accurate determination of the MMP. This study evaluates effects of important factors such as injection pressure, oil component composition, and injection gas composition on the MMP and recovery efficiency for slim tube and field-scale displacements. Two applicable MMP correlations were used for comparison and validation purposes. 展开更多
关键词 Empirical Correlation Minimum Miscibility Pressure Slim-Tube Soft experimentation Field-Scale Numerical Simulation Flue Gas Injection
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Educational Press for Remote Experimentation Applied in the Spring to Study Hooke's Law
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作者 Luan Carlos da Silva Casagranrde Vilson Gruber +3 位作者 Roberval Marcelino Yuri Crotti Lucas Boeira Michels Lirio Schaeffer 《Computer Technology and Application》 2015年第1期1-4,共4页
The aim of this study is to report the use of RE (remote experimentation) in an educational press. The authors developed this remote experiment with the objective to study the Hooke's law through the analysis of th... The aim of this study is to report the use of RE (remote experimentation) in an educational press. The authors developed this remote experiment with the objective to study the Hooke's law through the analysis of the coil spring. The remote experiment is available in a website, where the students can manipulate and observe the educational press and confirm Hooke's statements with the output information. In addition, the students will have the opportunity to read in the website about the educational press, the physical law, and the use of the press in industrial processes. This remote experimentation exerts a force in the mechanical spring creating a deformation. In the defined point, the microcomputer will collect the data from the sensors, and it will save this data in the database. After the process execution, a graph with the data will be plotted in the website. The tests confirm that the educational press has informational potential because it returned values consistent with Hooke's law and the experiment presented repetition in all tests realized. 展开更多
关键词 Educational press Hooke's law physical law industrial process remote experimentation.
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Tiêu Equation Experimentation of Understanding by Energy Transfer Quantum Mechanics
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作者 Huu S. Tieu Martin F. Loeffler 《Natural Science》 CAS 2023年第3期91-102,共12页
Background: The Tiêu equation has a ground roots approach to the process of Quantum Biology and goes deeper through the incorporation of Quantum Mechanics. The process can be measured in plant, animal, and human ... Background: The Tiêu equation has a ground roots approach to the process of Quantum Biology and goes deeper through the incorporation of Quantum Mechanics. The process can be measured in plant, animal, and human usage through a variety of experimental or testing forms. Animal studies were conducted for which, in the first day of the study all the animals consistently gained dramatic weight, even as a toxic substance was introduced as described in the introduction of the paper to harm animal subjects which induced weight loss through toxicity. Tests can be made by incorporating blood report results. Human patients were also observed to show improvement to their health as administration of the substance was introduced to the biological mechanism and plants were initially exposed to the substance to observe results. This is consistent with the Tiêu equation which provides that wave function is created as the introduction of the substance to the biological mechanism which supports Quantum Mechanics. The Tiêu equation demonstrates that Quantum Mechanics moves a particle by temperature producing energy thru the blood-brain barrier for example. Methods: The methods for the Tiêu equation incorporate animal studies to include the substance administered through laboratory standards using Good Laboratory Practices under Title 40 C.F.R. § 158. Human patients were treated with the substance by medical professionals who are experts in their field and have knowledge to the response of patients. Plant applications were acquired for observation and guidance of ongoing experiments of animals’ representative for the biologics mechanism. Results: The animal studies along with patient blood testing results have been an impressive line that has followed the Tiêu equation to consistently show improvement in the introduction of the innovation to biologic mechanisms. The mechanism responds to the substance by producing energy to the mechanism with efficient effect. For plant observations, plant organisms responded, and were seen as showing improvement thru visual observation. 展开更多
关键词 Tiêu Equation experimentation of Understanding by Energy Transfer Quantum Mechanics Golden Sunrise Nutraceutical Huu S. TIȆu Schrödinger Equation Quantum Mechanics Life Is Quantum Biology
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Experimentation of a Forced Convection Solar Dryer for Drying Sweet Potatoes at the Higher Institute of Technology of Mamou-Guinea
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作者 Ansoumane Sakouvogui Thierno Amadou Barry +1 位作者 Adama Moussa Sakho Mamby Keita 《World Journal of Engineering and Technology》 2023年第3期536-548,共13页
This study was carried out at the Mamou Higher Institute of Technology during the period from March 10 to April 15, 2022, with the aim of designing and testing a solar dryer with forced convection by drying potatoes. ... This study was carried out at the Mamou Higher Institute of Technology during the period from March 10 to April 15, 2022, with the aim of designing and testing a solar dryer with forced convection by drying potatoes. The dryer was designed using local materials. Its main geometric parameters are: 1) height of the drying chamber (90 cm), 2) length of the drying chamber (50 cm), 3) width of the drying chamber (43 cm), 4) surface of the racks (0.1806 m<sup>2</sup>), 5) surface of the heat accumulator (0.2537 m<sup>2</sup>). The experiment focused on the vacuum test of the dryer for two days and that of the drying of the sweet potato for three days from 8:30 a.m. to 5:30 p.m. The average vacuum test temperature values of the three environments are respectively accumulator (43°C), dryer chamber (41°C) and ambient environment (34°C). Four kilograms (4 kg) of boiled sweet potato were dried. The average temperatures in the accumulator and in the drying chamber during the three days of drying are respectively 33°C and 39°C. The final mass of the dried product is 1.2 kg, with a quantity of water extracted of 2 liters or 63% of the initial mass of the product. The average drying rate is 0.074 kg/h. The drying kinetics showed a decreasing rate in the absence of the heating period and the constant rate period. 展开更多
关键词 experimentation TEMPERATURE ACCUMULATOR Forced Convection Solar Dryer Sweet Potato
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Research and Experimentation for Clay Sedimentation in Aquatic Environment
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作者 Odysseas Kopsidas 《Journal of Environmental Science and Engineering(A)》 2021年第5期174-176,共3页
The clay in the aquatic environment begins to precipitate depending on the saturation level of the solution.The purpose of this work is to monitor this subsidence of the clay and to see its course with photographs.The... The clay in the aquatic environment begins to precipitate depending on the saturation level of the solution.The purpose of this work is to monitor this subsidence of the clay and to see its course with photographs.The photos are then analyzed with the Adobe Photoshop program,so that the students of the 3rd grade of the High School are able to follow the evolution of the precipitation phenomenon through the analysis of the photos and the probability density distribution function of the three pigments(RBG(Red-Blue-Green)in the technology course).The rate of clay settling as shown in the photos requires a prerequisite for the use of soil conditioners in specific clay soils.The students who participated in the workshop had the opportunity to get in touch with the phenomenon of subsidence,the processing of the brightness of the images with the program Adobe Photoshop and the study of soil improvement alternatives. 展开更多
关键词 CLAY SEDIMENTATION EXPERIMENT adobe photoshop soil conditioner
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Design, Fabrication and Experimentation of a Deep Drawing Machine
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作者 Ahmed Ramahi Yahya Saleh 《Journal of Mechanics Engineering and Automation》 2014年第10期804-812,共9页
This paper presents the work implemented in designing, fabricating and operating a model of a cheap hydraulic DDM (deep drawing machine), which is currently utilized in the manufacturing processes lab in the IED (I... This paper presents the work implemented in designing, fabricating and operating a model of a cheap hydraulic DDM (deep drawing machine), which is currently utilized in the manufacturing processes lab in the IED (Industrial Engineering Department) at An-Najah National University. The machine is used to conduct different experiments related to the deep drawing process. This work was implemented in three stages: the first was the design stage, in which all design calculations of the DDM elements were completed based on the specifications of the product (cup) to be drawn; the second was the construction stage, in which the DDM elements were fabricated and assembled at the engineering workshops of the university; the last was the operating and experimentation stage, in which the DDM was tested by conducting different experiments. The experience gained from designing and constructing such a mechanical lab equipment was found to be successful in terms of obtaining practical results that agree with those available in literature, cost-effective relative to the cost of a similar purchased equipment, as well as enhancing students' abilities in understanding the deep drawing process in particular and machine elements design concepts in general. 展开更多
关键词 Deep drawing machine element design die design machine assembly and fabrication experimental investigation of drawforce and draw stroke.
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High-throughput experimentation and machine learning-promoted synthesis of α-phosphoryloxy ketones via Ru-catalyzed P(O)O–H insertion reactions of sulfoxonium ylides
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作者 An Lin Jingyuan Liu +6 位作者 Yougen Xu Haiting Wu Yating Chen Yan Zhang Lebin Su Xiaodan Zhao Kuangbiao Liao 《Science China Chemistry》 2025年第2期679-686,共8页
Herein,we report a novel and highly efficient method for the synthesis ofα-phosphoryloxy carbonyl compounds via Rucatalyzed P(O)O–H insertion reactions of sulfoxonium ylides and phosphinic acids,with the assistance ... Herein,we report a novel and highly efficient method for the synthesis ofα-phosphoryloxy carbonyl compounds via Rucatalyzed P(O)O–H insertion reactions of sulfoxonium ylides and phosphinic acids,with the assistance of high-throughput experimentation(HTE)and machine learning(ML).A variety of P(O)O−H derivatives,including diarylphosphates,alkyl phosphates,and alkoxyphosphates,are competent candidates to react with sulfoxonium ylides in this transformation,and variousα-phosphoryloxy carbonyls and propylene phosphates are directly constructed.This approach utilizes readily available sulfoxonium ylide as a carbene precursor,and features mild conditions,operational simplicity,and broad functional groups tolerance,and could be used for late-stage functionalization of structurally complex bioactive molecules.Moreover,a conducive exploration of the reaction space is also conducted(756 reactions)and a machine learning model for reaction yield prediction has been developed and applied,showcasing the practical application of this newly workflow(HTE-ML)in the field of synthetic chemistry. 展开更多
关键词 α-phosphoryloxy ketones high-throughput experimentation machine learning P(O)O-H insertion sulfoxonium ylides
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Software Reliability Experimentation and Control 被引量:1
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作者 蔡开元 《Journal of Computer Science & Technology》 SCIE EI CSCD 2006年第5期697-707,共11页
This paper classifies software researches as theoretical researches, experimental researches, and engineering researches, and is mainly concerned with the experimental researches with focus on software reliability exp... This paper classifies software researches as theoretical researches, experimental researches, and engineering researches, and is mainly concerned with the experimental researches with focus on software reliability experimentation and control. The state-of-the-art of experimental or empirical studies is reviewed. A new experimentation methodology is proposed, which is largely theory discovering oriented. Several unexpected results of experimental studies are presented to justify the importance of software reliability experimentation and control. Finally, a few topics that deserve future investigation are identified. 展开更多
关键词 software reliability software experimentation software reliability control adaptive testing
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Right patient approach to experimental stromal cell therapies for gastrointestinal tumors
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作者 Francesca Vescio Silvia Curcio +2 位作者 Isabella Aquila Michele Ammendola Alessandro Pasquale Tarallo 《World Journal of Gastrointestinal Oncology》 2026年第1期282-286,共5页
Experimental therapies targeting immune and stromal cells,such as mast cells,cancer-associated fibroblasts,dendritic cells,and tumor endothelial cells,in the treatment of gastrointestinal solid tumors pose new and com... Experimental therapies targeting immune and stromal cells,such as mast cells,cancer-associated fibroblasts,dendritic cells,and tumor endothelial cells,in the treatment of gastrointestinal solid tumors pose new and complex surgical and medico-legal challenges.These innovative treatments require that informed consent not be limited to simple acceptance of the medical procedure,but instead reflect a true relational and cognitive process grounded in understanding,free choice,and the ability to revoke consent at any time.In particular,it is essential that the patient understands the experimental nature of the therapy,its development stage,potential benefits and risks,as well as the implications for their health and personal dignity.In the case of stromal cell-based treatments,which may exert complex immunomodulatory effects or activate angiogenic pathways that are not yet fully understood,patients must be made fully aware that they are participating in a non-standardized therapy whose outcomes,whether beneficial or harmful,cannot yet be predicted with certainty.This requires particularly careful medical communication,using simple yet scientifically accurate explanations delivered in appropriate language,along with a final verification of the patient’s actual understanding. 展开更多
关键词 Experimental therapies SURGERY Non-standardized treatment Gastrointestinal tumor Informed consent
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On the application of high-throughput experimentation and data-driven approaches in metallic glasses 被引量:6
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作者 Weijie Xie Weihua Wang Yanhui Liu 《Materials Genome Engineering Advances》 2023年第1期58-67,共10页
Materials genome engineering(MGE)has been successfully applied in various fields,resulting in a series of novel materials with excellent performance.Significant progress has been made in high-throughput simulation,exp... Materials genome engineering(MGE)has been successfully applied in various fields,resulting in a series of novel materials with excellent performance.Significant progress has been made in high-throughput simulation,experimentation,and data-driven techniques,enabling the effective prediction,rapid synthesis,and characterization of many classes of materials.In this brief review,we introduce the achievements made in the field of metallic glasses(MGs)using MGE,in particular high-throughput experimentation and data-driven approaches.High-throughput experiments help to efficiently synthesize and characterize many materials in a short period of time,enabling the construction of high-quality material databases for data-driven methods.Paired with machine learning,potential alloys of desired properties may be revealed and predicted.Along with the progress in computational power and algorithms of machine learning,the complex composition-structure-properties relationship is hopefully established,which in turn help efficient and precise prediction of new MGs. 展开更多
关键词 DATA-DRIVEN high-throughput experiment high-throughput simulation machine learning materials genome engineering metallic glasses
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Experimentation on Leader-Following Formation for Fixed-Wing UAVs
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作者 Tongyan Wu Yimin Deng +2 位作者 Dukun Xu Baitao Zhu Xuanhe Xiang 《Guidance, Navigation and Control》 2024年第2期194-200,共7页
Fixed-wing unmanned aerial vehicles(UAVs)are a primary focus of current UAV research.Challenges arise in theirflight due to high speed and complex maneuverability.This paper explores the coordinated turn guidance law ... Fixed-wing unmanned aerial vehicles(UAVs)are a primary focus of current UAV research.Challenges arise in theirflight due to high speed and complex maneuverability.This paper explores the coordinated turn guidance law for fixed-wing UAVs and validates an experimental leader-follower formation platform inflight.Results demonstrate the effectiveness of the proposed algorithm and platform in enabling actual leader-follower formationflights for fixed-wing UAVs. 展开更多
关键词 Fixed-wing unmanned aerial vehicles guidance law flight experiment leaderfollower formation
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Mechanisms of Baishao(Radix Paeoniae Alba)and Gancao(Radix Glycyrrhizae)on major depressive disorder:network pharmacology and in vivo validation
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作者 PEI Ke LI Yong +1 位作者 LIN Zhe LYU Guangfu 《Journal of Traditional Chinese Medicine》 2025年第5期1067-1077,共11页
OBJECTIVE:To elucidate the potential molecular mechanisms of Baishao(Radix Paeoniae Alba)(APR)and Gancao(Radix Glycyrrhizae)(GR)in the treatment of major depressive disorder(MDD).METHODS:Based on the network pharmacol... OBJECTIVE:To elucidate the potential molecular mechanisms of Baishao(Radix Paeoniae Alba)(APR)and Gancao(Radix Glycyrrhizae)(GR)in the treatment of major depressive disorder(MDD).METHODS:Based on the network pharmacology strategy,the therapeutic targets of APR-GR for MDD are predicted,differentially expressed genes from the Integrated Gene Expression database for MDD patients.Topological networks are constructed,Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways are enriched,their pharmacological potential molecular mechanisms are discussed,and molecular docking analysis is performed to further motivate compositional and target interactions.Finally,the CUMS mouse model is used for validation.RESULTS:Based on the pharmacological network analysis,17 candidate genes were identified,including muscarinic acetylcholine receptor M1(CHRM1),muscarinic acetylcholine receptor M2(CHRM2),β2-adrenergic receptor(ADRB2),adrenergicα1A receptor(ADRA1A)and 5-hydroxytryptamine transfer protein(SLC6A4),etc.which are primarily involved in reactive oxygen species metabolism,neural response,oxidative stress response and other biological processes.Further analysis revealed that these targets are closely related to Ca^(2+),cyclic adenosine monophosphate,etc.,and exhibit optimal binding sites after molecular docking.Finally,in vivo experiments were performed and it was found that APR-GR significantly improved depression-like behavior and hippocampal impairment in mouse models,increasing brain levels of 5-hydroxytryptamine,dopamine and norepinephrine and decreasing serum levels of corticotropin releasing hormone,corticosterone and adreno cortico tropic hormone,while upregulating the expression of CHRM1,CHRM2 and ADRA1A in the hippocampus and downregulating the expression of SLC6A4 and ADRB2.CNCLUSION:This research sheds light on the potential molecular mechanism of APR-GR to improve MDD. 展开更多
关键词 depressive disorder MAJOR animal experimentation molecular docking simulation network pharmacology Baishao(Radix Paeoniae Alba) Gancao(Radix Glycyrrhizae)
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Elucidating the process mechanism in Mg-to-Al friction stir lap welding enhanced by ultrasonic vibration 被引量:3
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作者 Ming Zhai Lei Shi ChuanSong Wu 《Journal of Magnesium and Alloys》 2025年第1期338-355,共18页
The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further impr... The composite structures/components made by friction stir lap welding(FSLW)of Mg alloy sheet and Al alloy sheet are of wide application potentials in the manufacturing sector of transportation vehicles.To further improve the joint quality,the ultrasonic vibration(UV)is exerted in FSLW,and the UV enhanced FSLW(UVeFSLW)was developed for making Mg-to-Al dissimilar joints.The numerical analysis and experimental investigation were combined to study the process mechanism in Mg/Al UVeFSLW.An equation related to the temperature and strain rate was derived to calculate the grain size at different locations of the weld nugget zone,and the effect of grain size distribution on the threshold thermal stress was included,so that the prediction accuracy of flow stress was further improved.With such modified constitutive equation,the numerical simulation was conducted to compare the heat generation,temperature profiles and material flow behaviors in Mg/Al UVeFSLW/FSLW processes.It was found that the exerted UV decreased the temperature at two checking points on the tool/workpiece interface from 707/671 K in FSLW to 689/660 K in UVeFSLW,which suppressed the IMCs thickness at Mg-Al interface from 1.7μm in FSLW to 1.1μm in UVeFSLW.The exerted UV increased the horizontal materials flow ability,and decreased the upward flow ability,which resulted in the increase of effective sheet thickness/effective lap width from 2.01/3.70 mm in FSLW to 2.04/4.84 mm in UVeFSLW.Therefore,the ultrasonic vibration improved the tensile shear strength of Mg-to-Al lap joints by 18%. 展开更多
关键词 Friction stir lap welding Mg-to-Al dissimilar alloys Ultrasonic vibration Numerical simulation Experimental investigation
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Effects of straw incorporation on biological nitrogen fixation under continuous and intermittent flooding irrigation in a rice cropping system 被引量:2
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作者 Yanhui ZHANG Jing WANG +7 位作者 Qi LIU Haihou WANG Tianlong HU Hui WANG Zhe CHEN Liangzuo SHU Elrys S.AHMED Zubin XIE 《Pedosphere》 2025年第2期364-372,共9页
Both straw incorporation and irrigation practices affect biological nitrogen(N)fixation(BNF),but it is still unclear how straw incorporation impacts BNF under continuous(CFI)or intermittent(IFI)flooding irrigation in ... Both straw incorporation and irrigation practices affect biological nitrogen(N)fixation(BNF),but it is still unclear how straw incorporation impacts BNF under continuous(CFI)or intermittent(IFI)flooding irrigation in a rice cropping system.A15N2-labeling chamber system was placed in a rice field to evaluate BNF with straw incorporation under CFI or IFI for 90 d.The nif H(gene encoding the nitrogenase reductase subunit)DNA and c DNA in soil were amplified using real-time quantitative polymerase chain reaction,and high-throughput sequencing was applied to the nif H gene.The total fixed N in the straw incorporation treatment was 14.3 kg ha^(-1)under CFI,being 116%higher than that under IFI(6.62 kg ha^(-1)).Straw incorporation and CFI showed significant interactive effects on the total fixed N and abundances of nif H DNA and c DNA.The increase in BNF was mainly due to the increase in the abundances of heterotrophic diazotrophs such as Desulfovibrio,Azonexus,and Azotobacter.These results indicated that straw incorporation stimulated BNF under CFI relative to IFI,which might ultimately lead to a rapid enhancement of soil fertility. 展开更多
关键词 heterotrophic diazotrophs irrigation practices 15N2-labeling experiment nifH cDNA nifH DNA soil fertility water management
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Isoproterenol mechanisms in inducing myocardial fibrosis and its application as an experimental model for the evaluation of therapeutic potential of phytochemicals and pharmaceuticals 被引量:1
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作者 Lujain Bader Eddin Mohamed Fizur Nagoor Meeran +2 位作者 Niraj Kumar Jha Samer NGoyal Shreesh Ojha 《Animal Models and Experimental Medicine》 2025年第1期67-91,共25页
Cardiac injury initiates repair mechanisms and results in cardiac remodeling and fi-brosis,which appears to be a leading cause of cardiovascular diseases.Cardiac fi-brosis is characterized by the accumulation of extra... Cardiac injury initiates repair mechanisms and results in cardiac remodeling and fi-brosis,which appears to be a leading cause of cardiovascular diseases.Cardiac fi-brosis is characterized by the accumulation of extracellular matrix proteins,mainly collagen in the cardiac interstitium.Many experimental studies have demonstrated that fibrotic injury in the heart is reversible;therefore,it is vital to understand differ-ent molecular mechanisms that are involved in the initiation,progression,and resolu-tion of cardiac fibrosis to enable the development of antifibrotic agents.Of the many experimental models,one of the recent models that has gained renewed interest is isoproterenol(ISP)-induced cardiac fibrosis.ISP is a synthetic catecholamine,sympa-thomimetic,and nonselectiveβ-adrenergic receptor agonist.The overstimulated and sustained activation ofβ-adrenergic receptors has been reported to induce biochemi-cal and physiological alterations and ultimately result in cardiac remodeling.ISP has been used for decades to induce acute myocardial infarction.However,the use of low doses and chronic administration of ISP have been shown to induce cardiac fibrosis;this practice has increased in recent years.Intraperitoneal or subcutaneous ISP has been widely used in preclinical studies to induce cardiac remodeling manifested by fibrosis and hypertrophy.The induced oxidative stress with subsequent perturbations in cellular signaling cascades through triggering the release of free radicals is consid-ered the initiating mechanism of myocardial fibrosis.ISP is consistently used to induce fibrosis in laboratory animals and in cardiomyocytes isolated from animals.In recent years,numerous phytochemicals and synthetic molecules have been evaluated in ISP-induced cardiac fibrosis.The present review exclusively provides a comprehensive summary of the pathological biochemical,histological,and molecular mechanisms of ISP in inducing cardiac fibrosis and hypertrophy.It also summarizes the application of this experimental model in the therapeutic evaluation of natural as well as syn-thetic compounds to demonstrate their potential in mitigating myocardial fibrosis and hypertrophy. 展开更多
关键词 cardiac fibrosis CATECHOLAMINES experimental models ISOPROTERENOL myocardial fibrosis PHYTOCHEMICALS β-adrenergic receptors
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Influence of ground fissures on metro shield tunnels:Large-scale experiment and numerical analysis 被引量:1
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作者 Yuxuan Gou Qiangbing Huang +2 位作者 Nina Liu Dongping Chen Jianbing Peng 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1356-1377,共22页
The recent upsurge in metro construction emphasizes the necessity of understanding the mechanical performance of metro shield tunnel subjected to the influence of ground fissures.In this study,a largescale experiment,... The recent upsurge in metro construction emphasizes the necessity of understanding the mechanical performance of metro shield tunnel subjected to the influence of ground fissures.In this study,a largescale experiment,in combination with numerical simulation,was conducted to investigate the influence of ground fissures on a metro shield tunnel.The results indicate that the lining contact pressure at the vault increases in the hanging wall while decreases in the footwall,resulting in a two-dimensional stress state of vertical shear and axial tension-compression,and simultaneous vertical dislocation and axial tilt for the segments around the ground fissure.In addition,the damage to curved bolts includes tensile yield,flexural yield,and shear twist,leading to obvious concrete lining damage,particularly at the vault,arch bottom,and hance,indicating that the joints in these positions are weak areas.The shield tunnel orthogonal to the ground fissure ultimately experiences shear failure,suggesting that the maximum actual dislocation of ground fissure that the structure can withstand is approximately 20 cm,and five segment rings in the hanging wall and six segment rings in the footwall also need to be reinforced.This study could provide a reference for metro design in ground fissure sites. 展开更多
关键词 Shield tunnel Ground fissure Large-scale experiment Mechanical performance Failure mode
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Roof deformation of the Beishan Rock Carvings with negative Poisson's ratio anchor support under varied precipitation conditions 被引量:1
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作者 YANG Peixi TAO Zhigang +1 位作者 YANG Xiaojie LI Xiaodan 《Journal of Mountain Science》 2025年第8期3078-3091,共14页
Beishan Rock Carvings in Chongqing,a renowned cultural heritage site in China,flourished during the Tang and Song dynasties and are often referred to as the“Stone Carving Art Museum of the Tang and Song Dynasties.”C... Beishan Rock Carvings in Chongqing,a renowned cultural heritage site in China,flourished during the Tang and Song dynasties and are often referred to as the“Stone Carving Art Museum of the Tang and Song Dynasties.”Cave 168 is a key component of the Beishan Rock Carvings.At present,several through-going cracks have developed in the roof of Cave 168,severely compromising the structural stability of the grotto.The early internal steel plate supports have suffered severe corrosion and can no longer provide effective reinforcement.In addition,the presence of steel columns obstructs visitor access and negatively affects the viewing experience.A new reinforcement method is urgently needed.Therefore,studying the deformation patterns of the structure is of critical importance.This study analyzes the stratigraphic parameters and fracture distribution of Cave 168,considering key influencing factors such as rainfall,self-weight,and the overlying Quaternary soil.On-site monitoring and physical model experiments were conducted to evaluate the changes in roof crack width and displacement before and after reinforcement with negative Poisson's ratio(NPR)anchor cables.The results reveal that the roof of Cave 168 contains several through-going cracks and numerous microcracks,which serve as infiltration channels for surface water.These accelerate the softening of the mudstone and pose a significant threat to the cave's structural safety.During the experiment,the main change in the crack exhibited a“semi-archshaped”propagation pattern.In the first ten minutes,as the rock transitioned from dry to moist conditions,a slight crack closure was observed.As rainfall continued,crack propagation accelerated.After rainfall ceased,crack width remained stable over a short period.Under NPR anchor support,the influence of rainfall on roof settlement was effectively mitigated,ensuring the safety and stability of the roof.The NPR anchors successfully limited the roof settlement to within 0.3 mm and provided effective control over both total and differential settlement.These findings offer valuable insights into the application of NPR anchor cables in the conservation of grotto heritage structures. 展开更多
关键词 Grotto stability Physical model experiment RAINFALL NPR anchor(cable) On-site monitoring
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Influences of maximum principal stress direction and cross-section shape on tunnel stability 被引量:1
20
作者 Xuefeng Si Zilong Zhang +4 位作者 Xibing Li Guansheng Yi Yong Luo Lihai Tan Kaifeng Han 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2159-2180,共22页
To investigate the effects of the maximum principal stress direction(θ)and cross-section shape on the failure characteristics of sandstone,true-triaxial compression experiments were conducted using cubic samples with... To investigate the effects of the maximum principal stress direction(θ)and cross-section shape on the failure characteristics of sandstone,true-triaxial compression experiments were conducted using cubic samples with rectangular,circular,and D-shaped holes.Asθincreases from 0°to 60°in the rectangular hole,the left failure location shifts from the left corner to the left sidewall,the left corner,and then the floor,while the right failure location shifts from the right corner to the right sidewall,right roof corner,and then the roof.Furthermore,the initial failure vertical stress first decreases and then increases.In comparison,the failure severity in the rectangular hole decreases for variousθvalues as 30°>45°>60°>0°.With increasingθ,the fractal dimension(D)of rock slices first increases and then decreases.For the rectangular and D-shaped holes,whenθ=0°,30°,and 90°,D for the rectangular hole is less than that of the D-shaped hole.Whenθ=45°and 60°,D for the rectangular hole is greater than that of the D-shaped hole.Theoretical analysis indicates that the stress concentration at the rectangular and D-shaped corners is greater than the other areas.The failure location rotates with the rotation ofθ,and the failure occurs on the side with a high concentration of compressive stress,while the side with the tensile and compressive stresses remains relatively stable.Therefore,the fundamental reason for the rotation of failure location is the rotation of stress concentration,and the external influencing factor is the rotation ofθ. 展开更多
关键词 Maximum principal stress direction Cross-section shape True-triaxial experiment Failure characteristics Fractal dimension Theoretical analysis
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