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Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KRUPIN M.R.NURGALIEV A.R.NEMETS I.A.ZEMTSOV S.d.SUNTSOV T.B.MYALTON d.S.SERGEEV N.A.SOLOVEV d.V.SARYchEV d.V.RYjAKOV S.N.TUGARINOV N.N.NAUMENKO National Research Centre“Kurchatov Institute” Moscow 123182Russia Bauman Moscow State Technical University Moscow 105005Russia Institution“Project Center ITER” Moscow 123098Russia jSC“SOLAR” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

Numerical calculation of Z-scan measurements for nonlinear media with large phase shift

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Optoelectronics Letters 2024年第3期20卷 177-182页

作者： M.d.Zidan A.Allahham department of Physics Atomic Energy Commission of SyriaP.O.Box 6091DamascusSyria

We have reported the characteristics of a Z-scan for the poly(azaneylylidene-acylene)(dAZA) polymer, as nonlinear medium with a large nonlinear phase shift using continuous-wave(CW) laser beam. It has been verified that the Fresnel diffraction model is applicable for analyses of Z-scan measurements with dAZA polymer at high laser power. It was found that Z-scan curves with peak-to-valley features appear as the applied light intensity increases in the case of a large nonlinear phase shift. The Z-scan experiments were carried out using a CW laser to verify the theoretical calculations in the case of a large nonlinear phase shift model. Our results show good agreements between the experimental data and the proposed theoretical models.

关键词： nonlinear phase media

Necrotic enteritis and antibiotic-free production of broiler chickens:challenges in testing and using alternative products

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Animal Nutrition 2024年第1期16卷 288-298页

作者： Robert j.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(NE) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, NE is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of NE control. While some of these feed additives have specific activity against the NE pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. Extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative NE treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis Clostridium perfringens Vaccines Feed additive Farm management

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自推进胶囊在小肠中移动时的优化控制

机械工程学报 2024年

作者：廖茂林李智朱佳鹏王泽旭 jOSEPHPáez chávez 北京科技大学机械工程学院北京科技大学井下智能控制研究院德累斯顿工业大学动力学研究中心

在消化道检测领域，传统的管线式内镜常给患者带来极大的心理负担与生理不适，胶囊内镜则因驱动方式和控制复杂等原因而难以对小肠部位开展全面而高效的检测。为此，考虑以双边约束的激振胶囊为研究对象，根据小肠结构的变化分别建立了... 详细信息

在消化道检测领域，传统的管线式内镜常给患者带来极大的心理负担与生理不适，胶囊内镜则因驱动方式和控制复杂等原因而难以对小肠部位开展全面而高效的检测。为此，考虑以双边约束的激振胶囊为研究对象，根据小肠结构的变化分别建立了扩张段和狭窄段的小肠-胶囊耦合动力学模型，并以小肠多变的摩擦环境以及对胶囊的包裹程度不同作为不稳定因素，分析了自推进胶囊的动力学行为规律。基于此，同时以胶囊的移动速度、单位能耗和对小肠壁冲击力作为优化目标，采用(Six-Sigma+NSGA-II+Monte-Carlo)组合优化算法获取胶囊可控移动对应的参数组合区间。最终，结合AdAMS动力学仿真与实验测试验证了当采用优化后的参数组合控制自推进胶囊时，可使其实现低能耗低冲击的定速定向移动。

关键词：小肠胶囊非光滑多目标优化运动控制

On the calibration of a shear stress criterion for rock joints to represent the full stress-strain profile

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journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 379-392页

作者： Akram deiminiat jonathan d.Aubertin Yannic Ethier department of Construction Engineering École de Technologie Supérieure(ÉTS)MontréalCanada

Conventional numerical solutions developed to describe the geomechanical behavior of rock interfaces subjected to differential load emphasize peak and residual shear *** detailed analysis of preand post-peak shear stress-displacement behavior is central to various time-dependent and dynamic rock mechanic problems such as rockbursts and structural instabilities in highly stressed *** complete stress-displacement surface(CSdS)model was developed to describe analytically the pre-and post-peak behavior of rock interfaces under differential *** formulations of the CSdS model required extensive curve-fitting iterations which limited its practical applicability and transparent integration into engineering *** present work proposes modifications to the CSdS model aimed at developing a comprehensive and modern calibration protocol to describe the complete shear stressdisplacement behavior of rock interfaces under differential *** proposed update to the CSdS model incorporates the concept of mobilized shear strength to enhance the post-peak ***’s concepts of joint roughness coefficient(jRC)and joint compressive strength(jCS)are incorporated to facilitate empirical estimations for peak shear stress and normal closure ***/uniaxial compression test and direct shear test results are used to validate the updated model and exemplify the proposed calibration *** results illustrate that the revised model successfully predicts the post-peak and complete axial stressestrain and shear stressedisplacement curves for rock joints.

关键词： Full shear profile Post-peak shear behavior Rock joint joint roughness coefficient(jRC) Axial stress-strain curve

Evaluation of the Reproduction Parameters of “Lohmann Brown” Strain chickens Fed with Cajanus cajan Leaf Meal in the Republic of Congo

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Open journal of Animal Sciences 2024年第3期14卷 234-248页

作者： Richard Missoko Mabeki Alexis jonas Ognika dora chérita Ekou Nathalie Myreille Ockoyi Parisse Akouango Laboratory of Animal Production and Biodiversity National School of Agronomy and Forestry Marien Ngouabi University Brazzaville Republic of the Congo department of Animal Production and Health Marien Ngouabi University Brazzaville Republic of the Congo

The objective of this study was to evaluate the reproductive parameters of “Lohmann Brown” strain chickens fed on Cajanus cajan leaves and to assess the viability of the chicks after hatching. 40 hens of the “Lohmann Brown” strain fed on Cajanus cajan leaf flour laid 219 eggs divided into four batches depending on the rate of incorporation of Cajanus cajan leaf flour in the rations (0%, 5%, 10% and 15%) were trained and introduced into the incubator. Results: the incubator indicates a hatching temperature of 38˚C to 37.2˚C and relative humidity of 60% to 70%. Hatching performance shows that: The 15% batch recorded the highest fertility rate 86.95% compared to 26.88% of the control batch. The CC 15% batch recorded the highest hatching rate 36.87. The lowest rate (17.18%) was recorded in the control batch (CC 0%). The highest embryonic mortality rate was recorded in the CC 15% batch. The lowest rate in the CC 10% batch. Concerning unfertilized eggs, the highest rate is 72.20% (CC 0%), and the lowest are (12.03%;57.42% and 66.66%) recorded in CC batches. 15%, CC 5% and CC 10% respectively. For the shell mortality rate, the highest is 18.58% recorded in the CC 15% batch. The lowest shell mortality rate is 2.07%, obtained in the control batch (CC 0%);the dust mortality rate was 0% for all chicks. The study seems to indicate that the incorporation of Cajanus cajan leaf meal up to 15% into the reproduction type ration in hens does not cause any harmful effects on the reproduction performance of laying hens.

关键词： Egg Incubation Hatching Fertility Mortality Viability

Connecting cellular mechanisms and extracellular vesicle cargo in traumatic brain injury

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Neural Regeneration Research 2024年第10期19卷 2119-2131页

作者： Nikita Ollen-Bittle Austyn d.Roseborough Wenxuan Wang jeng-liang d.Wu Shawn N.Whitehead department of Anatomy and Cell Biology Western UniversityLondonONCanada Schulich School of Medicine and dentistry Western UniversityLondonONCanada deparment of Clinical Neurological Sciences Western UniversityLondonONCanada

Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial activation and neuroinflammation, edema, ischemia, vascular injury, energy failure, and peripheral immune cell infiltration. The timing of these events post injury has been linked to injury severity and functional outcome. Extracellular vesicles are membrane bound secretory vesicles that contain markers and cargo pertaining to their cell of origin and can cross the blood-brain barrier. These qualities make extracellular vesicles intriguing candidates for a liquid biopsy into the pathophysiologic changes occurring at the cellular level post traumatic brain injury. Herein, we review the most commonly reported cargo changes in extracellular vesicles from clinical traumatic brain injury samples. We then use knowledge from animal and in vitro models to help infer what these changes may indicate regrading cellular responses post traumatic brain injury. Future research should prioritize labeling extracellular vesicles with markers for distinct cell types across a range of timepoints post traumatic brain injury.

关键词： axonal injury biomarkers blood-brain barrier chronic traumatic encephalopathy extracellular vesicles glial activation neuroinflammation traumatic brain injury

Academic Stress Assessment Using Virtual Reality as an Educational Tool in Spine Surgery

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Open journal of Modern Neurosurgery 2024年第2期14卷 114-123页

作者： diana chávez Lizárraga jesús Alberto Pérez Contreras Fernando Alvarado Gómez Evelyn Quintero Medina Emmanuel Cantú chávez Iván Ulises Sámano López Ana Sofía Peña Blesa department of Neurosurgery ángeles Pedregal Ciudad de México México department of Traumatology and Orthopedics Hospital Santa Fe Bogotá Colombia

Introduction: The evaluation of academic stress in medical students and residents is a topic of significant interest, given the considerable challenges they face during their learning process with traditional teaching methods. The use of technologies like virtual reality presents an opportunity to enhance their skills through simulations and training. The main objective of this study is to qualitatively assess the stress levels experienced by medical students and residents by integrating virtual reality into their current learning methods, aiming to improve their ability to manage stressors in their practice. Material and Methods: A questionnaire was conducted with 12 medical students and 12 Traumatology and orthopedics residents. The purpose of the questionnaire was to evaluate the levels of academic stress using the SISCO inventory. The stress levels were calculated by transforming average values into percentages, and the following criteria were assigned: 0 to 33% for Mild Stress, 34 to 66% for Moderate Stress, and 67 to 100% for deep Stress. Then, a virtual reality class focused on spine surgery was provided. Both medical students and residents were trained using the Non Nocere SharpSurgeon software platform and Oculus Quest 2 virtual reality glasses. At the end of the session, a second questionnaire related to the practice with virtual reality was conducted with the same evaluation criteria and a comparative analysis was carried out. Results: 12 undergraduate students from Hospital Angeles Mexico, CdMX and 12 traumatology and orthopedics residents at Hospital Santa Fe, Bogota were evaluated. The students in CdMX reported an average qualitative stress of 28.50% during habitual practices, which decreased to an average of 14.67% after virtual reality practice. Residents in Bogotá experienced an average qualitative stress of 30.50% with their current learning methods but this reduced to an average of 13.92% after using virtual reality. These findings indicate that t

关键词： Virtual Reality Academic Stress Learning Strategies Spine Surgery Training

Laboratory evaluation of toxicity of selected insecticides against egg and larval stages of cotton pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae)

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journal of Cotton Research 2024年第1期7卷 15-28页

作者： BUSNOOR Abhishek V. WAdASKAR R.M. FANd Babasaheb B. TAMBE V.j. PILLAI T. MAHULE d.j. NAGRARE V.S. PRASAd Y.G. Entomology Section College of Agriculture(Dr.Panjabrao Deshmukh Krishi Vidyapeeth)Nagpur 440001MaharashtraIndia Indian Council of Agricultural Research-Central Institute for Cotton Research Nagpur 441108MaharashtraIndia

Background The cryptic nature of pink bollworm Pectinophora gossypiella(Saunders)larvae enables its reduced vul-nerability to insecticidal ***,the development of resistance against Bacillus thuringiensis(Bt)toxins posed a serious threat to transgenic cotton *** necessitated determining the critical timing of spray applications on the control *** study assessed the influence of egg age(freshly laid ***-day-old)and the loca-tion of larvae(directly exposed to the insecticide residues on the boll rind *** inside the bolls)on insecticide control *** The results revealed a significant decrease in the ovicidal activity of tested insecticides with an increase in the age of eggs from one day old to three days old(paired t-test,Pdirectly exposed to the insec-ticide residues on the boll rind were more susceptible(>80%mortality)than the larvae exposed after they had bur-rowed inside the bolls(d insecticides on developmental biology were more pronounced in the experiment on pre-larval release insecticide treatment compared with insecticide treatment given post-larval release and entry inside the *** Egg age influences the insecticide susceptibility,as does the larval location,directly exposed vs bur-rowed inside the *** eggs and the larvae that had burrowed inside the green bolls of cotton were relatively less susceptible to the insecticide *** toxic effects of insecticides on egg and larval stages were primar-ily *** findings are significant for devising a comprehensive strategy for pink bollworm management on a sustainable basis.

关键词： Bioefficacy Cotton Insecticides Pink bollworm Pectinophora gossypiella Timings of spray