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Mechanisms And Influential Factors Of Rock Bursts In Tunneling Roadways Of Extra-Thick Coal Seams, Peng Yujie, Wang Qiang, Cao Anye, Xue Chengchun, Lyu Guowei, Hao Qi, Liu Yaoqi, Bai Xianxi, Li Dong

Coal Geology & Exploration

Objective Rock bursts occur frequently in tunneling roadways of extra-thick coal seams, significantly constraining safe coal mining. Investigating their mechanisms and influential factors is crucial to preventing and controlling such disasters in tunneling roadways of extra-thick coal seams. Methods Focusing on the tunneling roadway of mining face 250107-1 for an extra-thick coal seam within a coal mine in Gansu Province, this study established the discriminant indices for rock burst-induced roadway instability. By simulating the energy distribution patterns of surrounding rocks in the tunneling roadway using the FLAC^3D software, this study revealed the zonal energy characteristics of the surrounding rocks …

A Calculational Model For 3d Fault Complexity Based On Curvature Analysis And Fractal Dimensions, Yan Junsheng, Liu Zaibin, Fan Tao, Yang Hui, Liu Wenming, Du Wengang, An Lin, Liu Chenguang, Wang Xiaohui

Coal Geology & Exploration

Objective and Methods Faults are identified as one of the most threatening geological structural factors among hidden disaster-causing factors in coal mines. However, the 3D quantitative assessment of them remains challenging. Considering that existing quantitative indicators fail to fully reflect fault morphologies and there is a lack of 3D methods, this study proposed a calculational model for 3D fault complexity based on curvature analysis and fractal dimensions. This model improved the morphologies of traditional measurement volumes of fractal dimensions by employing the Delaunay tetrahedralization algorithm, thus effectively reducing the invalid values in calculating the 3D fractal dimensions of faults. Moreover, …

Exploration Of The Impacts Of Cement Sheath On Casing Stress Based On The Arching Effects Of Formations, An Fengchen, Miao Zhibo, Meng Siwei, Wei Ziying, Zhang Xiao, Zeng Jiaming, Wang Xiaohua

Coal Geology & Exploration

Objective With the growth in the demand for natural oil and gas and the technological progress of their production, the oil and gas well depths have been constantly setting new records. The increase in the depth corresponds to sharply increasing in-situ stress, leading to increasingly severe damage to the casing of ultradeep oil and gas wells. To enhance the bearing capacity of the casing under high in-situ stress, high-strength casing with a large wall thickness is typically employed, a measure which has been proved, however, less effective. Methods This study established a finite element model of the casing-cement sheath-formation system …

Commingling Production Of Deep Coal-Measure Gas Through Hydraulic Fracturing: Propagation Patterns Of Induced Fractures And Their Determinants, Chen Hao, Li Guozhang, Qin Yong, Wang Jianguo, Shen Jian, Sun Yuqi, Yuan Erjun, Li Dian

Coal Geology & Exploration

Objective The commingling production of coal-measure gas represents a pivotal approach to enhancing the single-well production of unconventional gas in China. However, coal-measure gas reservoirs exhibit distinctly different material compositions and physical properties, leading to uncertainty of the propagation modes and developmental degrees of fractures in different reservoirs during the hydraulic fracturing of coal-measure gas reservoirs subjected to commingling production. Therefore, effectively coordinating the stimulation of multiple reservoirs for multi-gas commingling production is crucial for minimizing production costs and maximizing production capacity. Methods This study investigated the Linxing block along the northeastern margin of the Ordos Basin as an example …

Application Of D-Insar In Monitoring The Impacts Of Shaft Grouting On Surface And Building Deformations, Liu Hui, Lu Rumeng, Su Lijuan, Cheng Shiguang, Zhang Pengfei, Cheng Hua

Coal Geology & Exploration

Objective In coal mining engineering, damaged well walls pose a threat to the safety of production facilities and mines. Comprehensively monitoring the impacts of shaft grouting on the deformations of mine surface plants and surface buildings is critical for ensuring the safe production of mines. Methods This study investigated a coal mine in the mining area within northern Anhui Province. Using the 15 scenes of Sentinel-1A image data covering the coal mine and the differential interferometric synthetic aperture radar (D-InSAR) technology, this study comprehensively monitored the subsidence of mine surface plants and surface buildings before and after shaft grouting, obtaining …

Fracture Structure Of The Overburden In The Layered Mining Of Extremely Thick Coal Seams: Developmental Patterns Of Caving Zones And Hydraulically Conductive Fracture Zones And Fracture Characteristics, Zhang Xin, Chen Youkuo, Meng Hailun, Qin Qifa, Cheng Xianggang, Huang Rongjie, Dong Hairui, Sun Wenbin, Qiao Wei

Coal Geology & Exploration

Objective The Zhunnan Coalfield, a coalfield on the southern margin of the Junggar Basin in Xinjiang, boasts abundant coal resources. However, water hazards in mines severely constrain the safe and efficient coal production in the coalfield. Since hydraulically conductive fractures in roofs serve as primary hydraulically conductive channels formed in the mining of the mining face, it is particularly crucial to investigate the developmental patterns of these fractures during the layered mining of extremely thick coal seams. Methods This study explored the (9-15)08 mining face of the Liuhuanggou Coal Mine in Xinjiang. Using ground exploration holes and borehole televiewers, this …

Hydrochemical Characteristics And Component Sources Of Water In Underground Reservoirs In The Daliuta Coal Mine, Zhang Haitao, Jiang Binbin, Zhang Haiqin, Li Peng, Wu Min, Hao Jingwei, Hu Yutian

Coal Geology & Exploration

Objective Underground reservoirs in coal mines are capable of storing and purifying mine water. A deep understanding of the hydrochemical characteristics and formation mechanisms of water in underground reservoirs is identified as an important prerequisite for large-scale development of technologies for mine water treatment. Methods This study investigated the underground reservoirs in the Daliuta Coal Mine within the Shendong area by testing and analyzing their influent and effluent water samples. Using methods such as the ion ratio method, multivariate statistical analyses (e.g., correlation analysis and principal component analysis (PCA)), and the positive matrix factorization (PMF) model, this study delved into …

Microscopic Fracture Characterization And Permeability Evolutionary Patterns Of Granites Under Cyclic Thermal Shock, He Jiangfu, Ren Chengcheng, He Kun, Yu Qihang, Li Xinru, Deng Xu

Coal Geology & Exploration

Objective This study aims to reveal the microscopic damage characteristics and permeability evolutionary patterns of high-temperature granite reservoirs fractured under cyclic thermal shock produced by low-temperature fluids like drilling fluids and circulating heat recovery media in the exploitation process of the enhanced geothermal systems (EGSs). Methods Using experiments on the fracturing characteristics of high-temperature granites under the conditions of varying cooling methods, numbers of thermal shock cycles, and cooling temperatures, this study determined microstructural characteristic parameters such as compressional wave (P-wave) velocity, pore volumetric fraction, and fractal dimension of granites across a temperature range of 25 to 700 ℃ under …

An Integrated Ecosystem Monitoring Technology For Coal Mining Subsidence Areas And Its Application In The Shendong Mining Area, Cheng Yang, Liu Wei, Zhang Na, Li Guanjie, Liu Kai, Zhang Chengye, Li Jun

Coal Geology & Exploration

Background The ecosystem monitoring of arid and semi-arid coal mining subsidence areas acts as a significant prerequisite for regional ecosystem conservation and management, holding critical significance for accelerating green mine construction. Methods Based on the Chinese government's regulatory requirements for mine ecosystems, this study analyzed the difficulties in ecosystem monitoring in the coal mining subsidence area of the Shendong mining area (also referred to as the Shendong coal mining subsidence area). By detailing the integrated coal-rock-water-soil-air-vegetation-carbon monitoring technology system, this study determined the factors, principal methods, and technology roadmap for the integrated ecosystem monitoring in the Shendong coal mining subsidence …

Identifying The Lithologies And Thicknesses Of Coal Seam Roofs And Floors Based On Multiparameter Logging Of Boreholes, Li Zhe, Gao Baobin, Lei Wenjie, Li Donghui, Li Zixin

Coal Geology & Exploration

Background In the process of coal mining, effective exploration methods for stratigraphic characteristics are crucial to underground operations. The reason is that the accurate stratigraphic characteristics of coal seams, along with the surrounding rocks of coal seam roofs and floors, facilitate the treatment of gas in coal seams, thereby ensuring safe and efficient coal mining. Methods Based on the multiparameter logging of boreholes crossing strata in a bottom drainage roadway, this study highlighted the lowstand, upgoing borehole trajectories, as well as the variations in parameters including natural gamma rays, spontaneous potential, and resistivity. By comprehensive comparison of the trajectories, video-derived …

Spatiotemporal Response Characteristics Of Transient Electromagnetic Field In Water-Bearing Goaves And Their Applications, Song Guilei, Gong Xufei, Yang Fuqiang, Cui Jianting, Li Zhanling, Liu Lina

Coal Geology & Exploration

Objective and Methods This study aims to enhance the accuracy of the mine transient electromagnetic method (MTEM) in of imaging of water-bearing goaves. Based on the geological conditions of the Gaojialiang Coal Mine, this study simulated the spatiotemporal response characteristics of the induced magnetic field in the water-bearing goaf model under varying stratigraphic spacings using finite element software COMSOL. Accordingly, this study analyzed the distribution patterns of the induced magnetic field on the apparent resistivity pseudosections and the plots of the differentials of longitudinal apparent conductivity. Using the results, the water-bearing conditions of goaves in the Ordos Gaojialiang Coal Mine …

Biomimetic Technologies For Drill Rods: Advances In Research And Development Trends, Wang Chuanliu, Ju Pei

Coal Geology & Exploration

Significance Drill rods are recognized as core tools in drilling engineering, and their performance exerts a significant influence on drilling efficiency and safety. Over recent years, applying biomimetic technologies to drill rod design has gradually emerged as a hot research topic. By imitating the remarkable structures, morphologies, and material properties of living organisms in nature, biomimetic technologies provide entirely new philosophies and approaches for the innovative design of drill rods. Advances This study summarizes the advances in research on biomimetic technologies for drill rods in terms of the biomimetic design of structures, morphologies, and materials. Regarding the biomimetic design of …

Non-Plus Ultra Ideologies In Multilingual Teacher Education Research: Towards Real Inclusion, David Martinez-Prieto, Xiaodi Zhou

Bilingual and Literacy Studies Faculty Publications

In this duo autoethnography, we reflect on the ideologies prevailing in the United States regarding the use of English as the de facto academic language. In a parallel manner, we analyze the ideologies embedded in the rejection of academic variations in other languages (i.e., Spanish and Mandarin). We collected data from 2016 to 2023 in physical and digital spaces while interacting with U.S. academia. To analyze our experiences, we used a framework that combined critical literacies and language ideologies. We found the rejection of non-English academic domains related to structural and epistemological ideologies present in some U.S. institutions and among …

Less Is More: Evaluating The Benefits Of Minimally Invasive Spinal Surgery, Ali Ahmed Mohamed, Rakan Alshaibi, Steven Faragalla, Garrett Flynn, Asad Khan, Emma Sargent, Youssef Mohamed, Camberly Moriconi, Cooper Williams, Zev Karve, Daniel Colome, Phillip Mitchell Johansen, Brandon Lucke-Wold

Student Publications

This review aims to explore the evolution, techniques, and outcomes of minimally invasive spine surgery (MISS) within the field of neurosurgery. We sought to address the increasing burden of spine degeneration in a rapidly aging population and the need for optimizing surgical management. This review explores various techniques in MISS, drawing upon evidence from retrospective studies, case series, systematic reviews, and technological advancements in neurosurgical spine treatment. Various approaches, including endonasal cervical, transoral cervical, transcervical, mini-open/percutaneous, tubular, and endoscopic techniques, provide alternatives for current approaches to a range of spinal pathologies. The main findings of this review highlight potential advantages …

Mechanistic Insights Into Plant Community Responses To Environmental Variables: Genome Size, Cellular Nutrient Investments, And Metabolic Tradeoffs, Erika Hersch-Green, Philip A. Fay, Hailee B. Hass, Nicholas G. Smith

Michigan Tech Publications

Affecting biodiversity, plants with larger genome sizes (GS) may be restricted in nutrient-poor conditions. This pattern has been attributed to their greater cellular nitrogen (N) and phosphorus (P) investments and hypothesized nutrient–investment tradeoffs between cell synthesis and physiological attributes associated with growth. However, the influence of GS on cell size and functioning may also contribute to GS-dependent growth responses to nutrients. To test whether and how GS is associated with cellular nutrient, stomata, and/or physiological attributes, we examined > 500 forbs and grasses from seven grassland sites conducting a long-term N and P fertilization experiment. Larger GS plants had increased cellular …

Impact Of American Thyroid Association's Revised Cancer Management Guidelines On Thyroid Cancer Incidence Trends: A Retrospective Cohort Study, 2000-2020, Vignesh K Nagesh

Faculty, Staff and Student Publications

Background: The past four decades have seen a steady increase in thyroid cancer in the United States (US). This study investigated the impact of the American Thyroid Association (ATA)'s revised cancer management guidelines on thyroid cancer incidence trends and how the trends varied by socioeconomic, histologic, geographic, and racial and ethnic characteristics from 2000 to 2020.

Methods: We used data from the Surveillance, Epidemiology, and End Results (SEER) database to identify thyroid cancer cases diagnosed among US patients between 2000 and 2020. We employed joinpoint regression software to fit, assess, and compare thyroid cancer incidence trends over time stratified by …

Artificial Intelligence In Fetal And Pediatric Echocardiography, Pei-Ni Jone

Faculty, Staff and Students Publications

Echocardiography is the main modality in diagnosing acquired and congenital heart disease (CHD) in fetal and pediatric patients. However, operator variability, complex image interpretation, and lack of experienced sonographers and cardiologists in certain regions are the main limitations existing in fetal and pediatric echocardiography. Advances in artificial intelligence (AI), including machine learning (ML) and deep learning (DL), offer significant potential to overcome these challenges by automating image acquisition, image segmentation, CHD detection, and measurements. Despite these promising advancements, challenges such as small number of datasets, algorithm transparency, physician comfort with AI, and accessibility must be addressed to fully integrate AI …

Multiparametric Cardiovascular Magnetic Resonance Is Associated With Outcomes In Pediatric Heart Transplant Recipients, Christina Laternser, Michael Markl, Cynthia K Rigsby, Joshua D Robinson, Nazia Husain

Faculty, Staff and Students Publications

BACKGROUND: Multiparametric cardiovascular magnetic resonance (CMR) has an emerging role in non-invasive surveillance of pediatric heart transplant recipients (PHTR). Higher myocardial T2, higher extracellular volume fraction (ECV), and late gadolinium enhancement (LGE) have been associated with adverse clinical outcomes in adult heart transplant recipients. The purpose of this study was to investigate the prognostic value of CMR-derived T1 and T2 mapping, ECV, and LGE for clinical outcomes in PHTR.

METHODS: We performed a single-center, retrospective chart review of consecutive, gadolinium-enhanced CMR studies in PHTR over a 7.5-year period, excluding follow-up studies. Standard CMR ventricular volume and function analysis, T1 mapping …

End-To-End Autonomous Quadcopter Using Reinforcement Learning, Mohamed Marwan Chawa

Theses and Dissertations

This thesis investigates the potential of Reinforcement Learning (RL) for achieving robust and adaptable quadcopter control, focusing on trajectory and attitude stabilization. We compare state-of-the-art RL algorithms, specifically Proximal Policy Optimization (PPO), against traditional Proportional-Integral-Derivative (PID) controllers across three tasks: hovering, slow trajectory following, and fast trajectory following. To enhance realism, we employ a modified PyFlyt simulation environment with a high-fidelity Crazyflie 2.x model, accounting for motor dynamics, noise, wind disturbances, and aerodynamic drag.

The challenge of operating a quadcopter can be divided into two distinct parts: planning a flight path and actually following that path. Our focus is on …

Conceptualizing Self-Reported Adverse Childhood Experiences: From Epidemiologic Exposure To Psychometric Latent Variable, Marianna D. Lanoue, Richard W. Hass

College of Population Health Faculty Papers

In this paper, we apply a measurement science perspective to explore both the epidemiologic and psychometric frameworks for the conceptualization, operationalization and assessment of self-reported adverse childhood experiences (srACEs). The epidemiologic paradigm suggests that srACEs are 'exposures', while the psychometric paradigm views responses on srACEs instrumentation as 'indicators'. It is the central premise of this paper that srACEs cannot be both exposures and indicators of scales. We review issues of reliability and validity from both perspectives, examine the degree of agreement between objective and subjective reports of childhood maltreatment and the implications of poor agreement, and conclude that the for …

High Peripheral T Cell Diversity Is Associated With Lower Risk Of Toxicity And Superior Response To Dual Immune Checkpoint Inhibitor Therapy In Patients With Metastatic Nsclc, Mehmet Altan, Ruoxing Li, Ziyi Li, Runzhe Chen, Ajay Sheshadri, Latasha Little, Jefferson Sinson, Natalie Vokes, Saumil Gandhi, Mara B Antonoff, Stephen G Swisher, Greg Lizee, Alexandre Reuben, John V Heymach, Jianjun Zhang

Faculty, Staff and Student Publications

INTRODUCTION: Despite significant successes, immune checkpoint blockade fails to achieve clinical responses in a significant proportion of patients, predictive markers for responses are imperfect and immune-related adverse events (irAEs) are unpredictable. We used T-cell receptor (TCR) sequencing to systematically analyze prospectively collected patient blood samples from a randomized clinical trial of dual immune checkpoint inhibitor therapy to evaluate changes in the T-cell repertoire and their association with response and irAEs.

METHODS: Patients with immunotherapy-naïve metastatic non-small cell lung cancer (NSCLC) were treated with ipilimumab and nivolumab according to trial protocol (LONESTAR, NCT03391869). Blood samples were systematically obtained at baseline (n=107), …

Diagnosis And Treatment Of Crop Inflammation Of Rough-Legged Buzzard (Buteo Lagopus) In Daqing Wildlife Nature Reserve, Heilongjiang Province, China, Wang Zheng, Ding Ruxin, Ge Yansong, Xu Enshuang, Zheng Jiasan

The Thai Journal of Veterinary Medicine

This article describes a Rough-legged Buzzard (Buteo lagopus) from the Wildlife Nature Reserve in Daqing, China. According to the staff of Daqing Wildlife Nature Reserve, the Rough-legged Buzzard was found to have impaired flight ability, depression, and loss of aggression, but its feathers were full and there were no obvious external injuries, so it was sent to the Wildlife Rehabilitation Center of the Teaching Animal Hospital of Heilongjiang Bayi Agricultural University for treatment. After the vet conducted X-ray and blood tests, he diagnosed the bird with a foreign body in the crop and crop inflammation. He finally treated …

Hematology, Blood Biochemistry And Cytochemical Characteristics Of Blood Cells Of Captive Aldabra Giant Tortoise (Aldabrachelys Gigantea) In Thailand, Thanida Haetrakul, Nitiwadee Keschumras, Sirawich Srisiri, Narinthip Chaiyanont, Nisama Wongnitipat, Phatcharaporn Phuasombatcharoen, Praewa Sirichitr, Nantarika Chansue

The Thai Journal of Veterinary Medicine

Aldabra giant tortoises (Aldabrachelys gigantea), well-known pet tortoises worldwide, were classified as Appendix II by The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). This study aims to investigate the hematological, blood biochemical, and cytochemical characteristics of blood cells in healthy Aldabra giant tortoises in captivity. Blood samples were collected from the dorsal tail vein of 12 tortoises (6 males and 6 females) during May and October 2022. The hematological values showed no statistically significant differences between male and female tortoises. However, in female tortoises, calcium and phosphorus levels were significantly higher than …

The Effects Of Propofol On Doppler Echocardiographic Values Of The Aorta, Main Pulmonary Artery, And Mitral E Wave In New Zealand White Rabbits, Mehmet Alper Çetinkaya, Mahir Kaya

The Thai Journal of Veterinary Medicine

The aim of this study was to determine the effects of propofol on acceleration time (AT), ejection time (ET), AT / ET ratio obtained from the aorta (Ao) and main pulmonary artery (MPA) and Doppler echocardiographic values of mitral E wave (E) in New Zealand white rabbits. Echocardiographic evaluation was performed in 40 conscious rabbits and repeated after propofol administration. The baseline mean values were 0.028±0.006 second (s) for Ao-AT, 0.116±0.017 s for Ao-ET, 0.24±0.036 for Ao-AT / ET, 0.05±0.01 s for MPA- AT, 0.137±0.018 s for MPA-ET, 0.38±0.037 s for MPA-AT/ET, 84.13±18.26 cm/s for E peak velocity, 3.06±1.38 mmHg …

Electoral College Subversion, The Vice President & The Federal Writ Of Mandamus, Benjamin Sevart

Tennessee Journal of Law and Policy

No abstract provided.

Front Matter Fall 2024

Tennessee Journal of Law and Policy

No abstract provided.

Impacto De La Pandemia De La Covid-19 En Las Familias De Los Jóvenes Universitarios De Las Poblaciones Rurales Mayas Del Estado De Yucatán, Jorge Atocha Pacheco Castro

Journal of Maya Heritage

Abstract. This study examines the impacts of the COVID-19 pandemic on the families of university students from rural Maya communities in Yucatán, Mexico. Utilizing an anthropological framework, the research highlights the interplay of structural vulnerabilities and cultural resilience. It explores how families navigated economic challenges, social interactions, and cultural practices amid the crisis. Key findings include the reliance on traditional subsistence practices such as small-scale agriculture and backyard farming, which provided a safety net during economic downturns. Socially, rural families reported lower stress levels and stronger communal bonds compared to their urban counterparts, owing to expansive living spaces and outdoor …

Mr. Joe Reed

African American Funeral Programs

Handwritten Announcement.

Indeterminate Stepper User Interface For Complex Data Entry Tasks, Neha Karve, Ramprasad Sedouram, Yun Theng Kwok

Defensive Publications Series

In many contexts, users are required to fill in forms to provide their information. When a large amount of data is to be entered, the forms can be complex, multi-step data entry tasks. It is difficult for users to determine their overall progress through such a form as well as portions of the form that are still incomplete. This disclosure describes a user interface that divides the data entry task into multiple sections. Each section is configurable and includes a small, manageable set of steps. Progress in each section is indicated visually via a section-specific progress bar. Overall progress is …

Health Literacy On Physical Therapy Among Senior Citizens With Physical Disability And Community Health Workers, Kriza G. Ganotisi, Faye Angelene J. Barangay, Andrew A. Galang, Wina Frances Q. Lazaro, Christopher U. Rivera, Ryan Dean T. Sucgang

Philippine Journal of Physical Therapy

Introduction. This study was conducted to determine the health literacy on physical therapy (PT) among senior citizens with physical disability and community health workers (CHWs). Specifically, it identified the sociodemographic profile of the CHWs and senior citizens with physical disability, their extent of health literacy on PT as to prose, document and numeracy and how health policies, availability of PT programs, and available equipment and facilities for the rendition of PT services affect their health literacy.

Methods. This study employed a descriptive research design. The respondents of the study involved 18 CHWs and 29 senior citizens. It was conducted in …