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Refinement of the Proposed Gamma-Ray Burst Time Delay Model

International Journal of Astronomy and Astrophysics 2024年第2期14卷 120-147页

作者： Godson Fortune Abbey Joseph Simfukwe Prospery christopher Simpemba Saul Paul Phiri Alok Srivastava Golden Gadzirayi Nyambuya Department of Physic School of Mathematics and Natural Sciences The Copperbelt University Kitwe Republic of Zambia Fundamental Theoretical and Research Group Department of Applied Physics Faculty of Applied Sciences National University of Science & Technology Bulawayo Republic of Zimbabwe

This paper is the second instalment in our study of the observed time delay in the arrival times of radio photons emanating from Gamma Ray Bursts (GRBs). The mundane assumption in contemporary physics as to the cause of these pondersome time delays is that they are a result of the photon being endowed with a non-zero mass. While we do not rule out the possibility of a non-zero mass for the photon, our working assumption is that the major cause of these time delays may very well be that these photons are travelling in a rarefied cosmic plasma in which the medium’s electrons interact with the electric component of the Photon, thus generating tiny currents that lead to dispersion, hence, a frequency-dependent speed of Light (FDSL). In the present instalment, we “improve” on the model presented in the first instalment by dropping the assumption that the resultant pairs of these radio photons leave the shock front simultaneously. The new assumption of a non-simultaneous— albeit systematic—emission of these photon pairs allows us to obtain a much more convincing and stronger correlation in the time delay. This new correlation allows us to build a unified model for the four GRBs in our sample using a relative distance correction mechanism. The new unified model allows us to obtain as our most significant result a value for the frequency equivalence of the interstellar medium (ISM)’s conductance ν* ~ 1.500 ± 0.009 Hzand also an independent distance measure to the GRBs where we obtain for our four GRB samples an average distance of: ~69.40 ± 0.10, 40.00 ± 0.00, 58.40 ± 0.40, and 86.00 ± 1.00 Mpc, for GRB 030329, 980425, 000418 and 021004 respectively.

关键词： Gamma-Ray Bursts (GRB) Photon Mass Plasma Time Delay Fireball Model

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青藏高原腹地发现最早细石叶技术遗址

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中国科学：地球科学 2024年第5期54卷 1588-1601页

作者：靳英帅张晓凌王社江葛俊逸何伟达娃谭韵瑶杨紫衣 christopher MORGAN 高星中国科学院脊椎动物演化与人类起源重点实验室中国科学院古脊椎动物与古人类研究所北京100044 中国科学院大学北京100049 西藏自治区文物保护研究所拉萨850000 那曲市文化和旅游局那曲852000 University of Nevada Reno 87557USA

细石叶技术产品是青藏高原发现最丰富的史前人类文化遗物,代表了早期人类在高原的大规模迁徙.然而,经过系统发掘、具有可靠年代数据的细石叶技术遗址在青藏高原发现较少,高原腹地更为缺乏,这对理解细石叶技术人群在高原大规模迁徙扩散... 详细信息

细石叶技术产品是青藏高原发现最丰富的史前人类文化遗物,代表了早期人类在高原的大规模迁徙.然而,经过系统发掘、具有可靠年代数据的细石叶技术遗址在青藏高原发现较少,高原腹地更为缺乏,这对理解细石叶技术人群在高原大规模迁徙扩散的时间和过程带来了诸多障碍.本文研究报道了青藏高原腹地海拔4600m处新发现的细石叶技术遗址——尼阿底遗址第3地点.技术-类型学分析结果显示,尼阿底遗址第3地点细石叶的生产主要包括楔形石核和半锥形石核两种技术,与旧石器时代晚期中国华北地区的细石叶技术特征接近.光释光测年(OSL)和碳十四测年(^(14)C)的结果表明,尼阿底遗址第3地点的年代为11000~10000a BP.尼阿底遗址第3地点作为目前青藏高原腹地发现的最早的细石叶技术遗址,为了解拥有细石叶技术的狩猎采集者到达高原腹地的时间及其可能的扩散路线提供了重要信息.另外,通过对整个高原细石叶技术发展的分析,结合分子生物学的成果对比显示,细石叶技术人群迁移进入高原可能与人类对高原的长期占领以及现代藏族人的形成有密切联系.

关键词：青藏高原腹地尼阿底遗址第3地点细石叶技术早全新世高海拔适应

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Using Linear and Non-Linear Techniques to Characterize Gait Coordination Patterns of Two Individuals with NGLY1 Deficiency

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Case Reports in Clinical Medicine 2024年第9期13卷 391-409页

作者： Charles S. Layne Dacia Martinez Diaz christopher A. Malaya Brock Futrell Christian Alfaro Hannah E. Gustafson Bernhard Suter Department of Health and Human Performance University of Houston Houston TX USA Center for Neuromotor and Biomechanics Research University of Houston Houston TX USA Center for Neuro Engineering and Cognitive Science University of Houston Houston TX USA Research Center Parker University Dallas TX USA Blue Bird Circle Rett Center Texas Childrens Hospital Houston TX USA Baylor College of Medicine Houston TX USA

Individuals with NGLY1 Deficiency, an inherited autosomal recessive disorder, exhibit hyperkinetic movements including athetoid, myoclonic, dysmetric, and dystonic movements impacting both upper and lower limb motion. This report provides the first set of laboratory-based measures characterizing the gait patterns of two individuals with NGLY1 Deficiency, using both linear and non-linear measures, during treadmill walking, and compares them to neurotypical controls. Lower limb kinematics were obtained with a camera-based motion analysis system and bilateral time normalized lower limb joint time series waveforms were developed. Linear measures of joint range of motion, stride times and peak angular velocity were obtained, and confidence intervals were used to determine if there were differences between the patients and control. Correlations between participant and control mean joint waveforms were calculated and used to evaluate the similarities between patients and controls. Non-linear measures included: joint angle-angle diagrams, phase-portrait areas, and continuous relative phase (CRP) measures. These measures were used to assess joint coordination and control features of the lower limb motion. Participants displayed high correlations with their control counterparts for the hip and knee joint waveforms, but joint motion was restricted. Peak angular velocities were also significantly less than those of the controls. Both angle-angle and phase-portrait areas were less than the controls although the general shapes of those diagrams were similar to those of the controls. The NGLY1 Deficient participants’ CRP measures displayed disrupted coordination patterns with the knee-ankle patterns displaying more disruption than the hip-knee measures. Overall, the participants displayed a functional walking pattern that differed in many quantitative ways from those of the neurotypical controls. Using both linear and non-linear measures to characterize gait provides a more compre

关键词： NGLY1 Gait Disability Kinematics Angle-Angle Diagrams Phase Portraits

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Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique

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World Journal of Nuclear Science and Technology 2024年第2期14卷 97-106页

作者： Alassane Traore Anna Ndiaye christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye Ababacar Sadikhe Ndao Département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal Département de Chimie Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal Tandetron Laboratory IBA Group iThemba LABS Cape Town South Africa Africa Rice Center St. Louis Senegal

Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species.

关键词： PIXE 2D Mapping Rice Concentration Elemental Analysis

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Assessing the Efficacy of Wheat-Soybean Based Intercropping System at Different Plant Densities in Bambili, Cameroon

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American Journal of Plant Sciences 2024年第4期15卷 235-251页

作者： Lendzemo E. Tatah Jeazet K. Teitiogo Oben Tom Tabi Tange D. Achiri Njualem D. Khumbah Chi christopher Tamu Department of Crop Production Technology College of Technology University of Bamenda Bambili Cameroon Department of Agronomic and Applied Molecular Sciences Faculty of Agriculture and Veterinary Medicine University of Buea Buea Cameroon School of Tropical Agriculture and Natural Resource Catholic University of Cameroon Bamenda Cameroon Department of Agricultural and Environmental Engineering College of Technology University of Bamenda Bambili Cameroon

Wheat is one of the most important cereals in the world, serving as a staple for millions globally. In the wake of the geopolitical crisis between Russia and Ukraine, it has become incumbent for many countries to invest in wheat production. Improving cropping systems for wheat production is paramount. Intercropping cereals with legumes has tremendous advantages. Therefore, this study was designed to optimize wheat production by intercropping it with soybean at different densities. Between March and August 2023, a randomized complete block design trial was conducted in Bambili, North West of Cameroon with treatments T1 (wheat monocrop at 200,000 plants ha−1), T2 (soybean monocrop at 250,000 plants ha−1), T3 (200,000 wheat and 125,000 soybean ha−1), T4 (100,000 wheat and 250,000 soybean ha−1), T5 (200,000 wheat and 250,000 soybean ha−1) and T6 (100,000 wheat and 125,000 soybean ha−1). Results revealed that growth parameters of wheat were not significantly influenced by monocrop or intercrop. The yield of wheat was significantly higher in the monocrop than the intercrop treatments, with slight variation amongst the intercrop treatments. Soybean yield was higher in the monocrop than in the intercrop, with no variations amongst the intercrop treatments. Only the land equivalence ratio (LER) for T5 was greater than 1.0. The competitive ratio for T5 was 0.54 for wheat and 1.90 for soybean, comparatively lower than the other monocrop treatments. Intercropping wheat and soybean at 200,000:250,000 ratio is recommended.

关键词： Competitive Ration Land Equivalence Ration Intercrop Soybean Wheat

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克里斯多夫·勒·布伦:真相即感知

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青年视觉 2024年第3期 148-159页

作者： dawenwen christopher Le Brun(图) 里森画廊(图) 不详

日前,英国艺术家克里斯多夫,勒:布伦(christopher Le Brun)在里森画廊北京空间举办了全新个展「月相」。作为英国当代著名的画家、版画家和雕塑家,克里斯多夫,勒:布伦以其独特的艺术风格和深刻的哲学思考,赢得了国际艺术界的认可。VISIO... 详细信息

日前,英国艺术家克里斯多夫,勒:布伦(christopher Le Brun)在里森画廊北京空间举办了全新个展「月相」。作为英国当代著名的画家、版画家和雕塑家,克里斯多夫,勒:布伦以其独特的艺术风格和深刻的哲学思考,赢得了国际艺术界的认可。VISION也借助此次展览的机会,对克里斯多夫·勒·布伦进行了专访。

关键词：布伦雕塑家艺术风格哲学思考

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地表-地下过程耦合的数值水文模型综述

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中国科学：地球科学 2024年第5期54卷 1484-1505页

作者：舒乐乐陈昊孟宪红常燕胡立堂王文科束龙仓俞烜 christopher DUFFY 姚莹莹郑东海中国科学院西北生态环境资源研究院冰冻圈科学与冻土工程重点实验室兰州730000 北京师范大学水科学研究院北京100875 长安大学水利与环境学院西安710054 河海大学水文水资源学院南京210098 中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室南京210008 Pennsylvania State University State CollegePA 16801USA 西安交通大学地球环境科学系西安710054 中国科学院青藏高原研究所北京100101

水文模型是利用数学公式对水文循环过程的描述,是理解自然界水的时空运动和分布规律的重要工具;它不仅可以利用观测数据来验证理论的可靠性与适宜性,还能预测水文变量未来趋势,实现理解自然与预测自然的目的.随着计算方法的快速发展、... 详细信息

水文模型是利用数学公式对水文循环过程的描述,是理解自然界水的时空运动和分布规律的重要工具;它不仅可以利用观测数据来验证理论的可靠性与适宜性,还能预测水文变量未来趋势,实现理解自然与预测自然的目的.随着计算方法的快速发展、观测与试验手段的持续更新,目前基于物理过程的地表-地下过程耦合的数值水文模型快速发展.这种模型以微观尺度的守恒原理和物理公式为基础,利用数值方法将地表和地下水流进行耦合计算,从而模拟流域尺度水文响应过程.由于其物理过程明确、时空分辨率高且利于学科耦合,数值水文模型已成为水文模型发展的前沿和主流方向之一.本文阐述了地表-地下过程耦合数值水文模型的理论基础,从模型框架、数值求解方法、空间表达和耦合算法等方面对比和分析了当前主流数值水文模型,同时与传统水文模型比较,厘清了数值水文模型的优劣势,探讨了未来数值水文模型发展的方向.

关键词：数值水文模型地表-地下过程耦合数值方法水文模型

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Quantifying Kinematic Tremor in an NGLY1-Deficient Individual: A Case Study

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Case Reports in Clinical Medicine 2024年第1期13卷 25-36页

作者： Brock Futrell christopher Alexander Malaya Dacia Martinez Diaz Christian Alfaro Hannah Elizabeth Gustafson Subhalakshmi Chandrasekaran Rhea Mohan Phatak Bernhard Suter Charles Shannon Layne Department of Health and Human Performance University of Houston Houston USA Center for Neuromotor and Biomechanics Research University of Houston Houston USA Department of Computer Science and Engineering Texas A&M University College Station USA Blue Bird Circle Rett Center Texas Children’s Hospital Houston USA Baylor College of Medicine Houston USA Center for NeuroEngineering and Cognitive Science University of Houston Houston USA

NGLY1 Deficiency is an autosomal recessive congenital disorder that has been identified in less than 100 individuals. Most individuals with NGLY1 Deficiency display hyperkinetic movement disorders, including choreiform, athetoid, dystonic myoclonic, dyskinetic, and dysmetric movements. Developing a consistent and concise consensus on the classification and evaluation of tremors is essential to forward the research and treatment of tremors. It has also been reported that some individuals with NGLY1 Deficiency demonstrate tremor, but such tremor has never been formally investigated. The primary objective of this study is to determine if an individual with NGLY1 Deficiency demonstrates an identifiable tremor during a series of arm movements and, if so, describe the frequency and power characteristics of that tremor. Arm movement kinematics were obtained using a 16-camera Vicon system, and time series trajectory waveforms for three planes of a marker placed on the hand were developed. Custom MATLAB scripts were utilized to compute Fast Fourier Transformations of the data within the identified waveform segments. A mean frequency of 2.30 Hz (SD = 1.05) with a mean power of 5.02 |P1(f)| (SD = 4.63) suggests that our participant’s kinematic data did display a persistent tremor in both hands across all tasks and movement planes. Analyses of the reaching hand and the non-reaching hand suggest the participant displayed an action tremor in both postural and intention (kinetic) tremors. Future directions should include assessing additional individuals with NGLY1 Deficiency to determine if the tremor is a distinguishable disorder behavior. Additionally, evaluating other anatomical sites, such as the elbow, head, and lower limbs, would provide further insights into the characteristics of this tremor.

关键词： Tremor NGLY Fast Fourier Transformation Reaching Hyperkinetic Movement

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Comment on: Effect of intubation in patients with functional epiphora after endoscopic dacryocystorhinostomy

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1576-1576页

作者： Mansooreh Jamshidian-Tehrani Hossein Ghahvehchian christopher J Compton Jeremy D Clark Nicole L West Mohsen Bahmani Kashkouli Department of Ophthalmology Eye Research CenterThe Five Senses Health InstituteRassoul Akram HospitalIran University of Medical SciencesTehran ***Iran Department of Ophthalmology and Visual Sciences University of Louisville School of MedicineLouisville 40202KentuckyUSA

Dear Editor,We read with interest the article by Han et al[1]in which they retrospectively assessed the effect of bicanalicular intubation for functional epiphora after a failed endoscopic dacryocystorhinostomy(DCR).They confirmed the post-DCR“functional obstruction”based on fluorescein dye disappearance(FDDT)and irrigation test[1].

关键词： intubation assessed endoscopic

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Protecting miners from coal bursts during development above historic mine workings in Harlan County,KY

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International Journal of Mining Science and Technology 2021年第1期31卷 111-116页

作者： christopher Mark Mine Safety and Health Administration PittsburghPA 15236USA

In order to reach a large,untapped reserve of high-quality coal,D8 Cloverlick Mine proposed to mine a corridor nearly 600 m deep beneath the Benham Spur of Black Mountain,Kentucky’s highest peak.D8 Cloverlick Mine was extracting the Owl seam,but the corridor’s route lay approximately 20 m above century-old mine workings in the C–(Darby)*** to the concern,three serious coal bursts had recently occurred in nearby Owl seam *** of the old workings seemed to indicate that the underlying C–seam had been fully ***,two of the coal bursts had occurred above areas where the C–Seam was also shown as mined *** Safety and Health Administration(MSHA)Technical Support therefore investigated the records of past mining to better understand the old mine *** conditions observed in current Owl seam workings were also compared with the maps of the old C–seam *** study concluded that the presence of hazardous underlying remnants could not be ruled *** mitigate the burst risk,D8 Cloverlick Mine adopted a strategy of stress probe drilling.A self-propelled coal drill was used to auger 11.5-m-long,small diameter holes in advance of *** each hole was drilled,the cuttings were measured to detect the presence of highly stressed *** the crossing was successfully completed without incident.

关键词： Coal bursts Underground mining Room-and-pillar Destressing

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