Effects of functional strength training on pain, function, and lower extremity biomechanics in patients with patellofemoral pain syndrome: a randomized clinical trial.

Background: Patellofemoral pain syndrome (PFPS) is a common disorder affecting the lower extremity. This study aimed to compare the effects of functional strength training (FST) and standard strength training (SST) in PFPS patients.

Methods: Forty college students (aged 18-30 years) with PFPS and no exercise habits were randomized into FST group (n = 20) and SST group (n = 20).

Study on the law of air leakage in goaf under the influence of double-series coal seam mining.

In order to solve the engineering problem of a large amount of wind leakage in the 8106 comprehensive mining working face of the Carboniferous System under the influence of overlapping mining of two coal seams in Yongdingzhuang Mine, Datong Mining Area, this paper utilizes finite element numerical simulation software to study the wind leakage characteristics of the 8106 working face and the distribution range of the spontaneous combustion "three zones" of the mining area. The results show that, under the condition of external air leakage, the internal pressure of the goaf is greater than the external pressure, the upper pressure is greater than the lower pressure, and the seepage direction is from the top down and from the inside out. Under the condition of no external air leakage, the air leakage source is mainly concentrated in the air inlet lane.

Molecular structure characteristic of coals of different rank.

Context: Understanding the structural characteristics of coal at the molecular level is fundamental for its effective utilization. To explore the molecular structure characteristic, the long-flame coal from Daliuta (DLT), coking coal from Yaoqiao (YQ), and anthracite from Taixi (TX) were investigated using various techniques such as elemental analysis, Fourier transform infrared spectroscopy, solid-state C nuclear magnetic resonance spectroscopy, and X-ray photoelectron spectroscopy. Based on the structural parameters, the coal molecular model was constructed and optimized.

In Situ Construction of a Porous Nanotrap: A Pathway for Catalyst Performance Optimization.

Supported noble metal catalysts have a high catalytic activity and selectivity. However, fast surface reconstruction and sintering of noble metal particles during a high-temperature reaction process pose a major challenge to the stability of the catalysts. In this study, sinter-resistant supported noble metal catalysts were prepared by constructing an oxide nanotrap.

Scale-Consistent and Temporally Ensembled Unsupervised Domain Adaptation for Object Detection.

Unsupervised Domain Adaptation for Object Detection (UDA-OD) aims to adapt a model trained on a labeled source domain to an unlabeled target domain, addressing challenges posed by domain shifts. However, existing methods often face significant challenges, particularly in detecting small objects and over-relying on classification confidence for pseudo-label selection, which often leads to inaccurate bounding box localization. To address these issues, we propose a novel UDA-OD framework that leverages scale consistency (SC) and Temporal Ensemble Pseudo-Label Selection (TEPLS) to enhance cross-domain robustness and detection performance.

The Role of Social Integration in Chronic Disease Prevalences Among the Internal Migrant Populations in China: Evidence from a National Survey.

: China has the world's largest internal migrant population, yet chronic disease prevalence among this group remains largely overlooked. The integration of the internal migrant population into the local society may affect their noncommunicable disease prevalences and become a challenge for the public health system. This study aimed to explore the association between the social integration of China's internal migrant population and the prevalences of chronic diseases, including hypertension and diabetes.

Research on Downhole MTATBOT Positioning and Autonomous Driving Strategies Based on Odometer-Assisted Inertial Measurement.

In response to the current situation of backward automation levels, heavy labor intensities, and high accident rates in the underground coal mine auxiliary transportation system, the mining trackless auxiliary transportation robot (MTATBOT) is presented in this paper. The MTATBOT is specially designed for long-range, space-constrained, and explosion-proof underground coal mine environments. With an onboard perception and autopilot system, the MTATBOT can perform automated and unmanned subterranean material transportation.

Effects of Increasing the Nitrogen-Phosphorus Ratio on the Structure and Function of the Soil Microbial Community in the Yellow River Delta.

Nitrogen (N) deposition from human activities leads to an imbalance in the N and phosphorus (P) ratios of natural ecosystems, which has a series of negative impacts on ecosystems. In this study, we used 16s rRNA sequencing technology to investigate the effect of the N-P supply ratio on the bulk soil (BS) and rhizosphere soil (RS) bacterial community of halophytes in coastal wetlands through manipulated field experiments. The response of soil bacterial communities to changing N and P ratios was influenced by plants.

Research on Stability of Removal Function in Figuring Process of Mandrel of X-Ray-Focusing Mirror with Variable Curvature.

Over the past 30 years, researchers have developed X-ray-focusing telescopes by employing the principle of total reflection in thin metal films. The Wolter-I focusing mirror with variable-curvature surfaces demands high precision. However, there has been limited investigation into the removal mechanisms for variable-curvature X-ray mandrels, which are crucial for achieving the desired surface roughness and form accuracy, especially in reducing mid-spatial frequency (MSF) errors.

Research on the acoustic emission characteristics and instability correlation effect of the dynamic response of waste dump slopes.

Due to the fluidity of the loose medium inside the waste dump slope, the traditional monitoring system cannot fully reflect the misalignment and slip between particles inside the medium, and it is also difficult to capture the precursor information of the slip of the loose accumulation body. To reveal the dynamic evolution process of the slope instability of the waste dump slope, the coupling test system of the slope instability of the waste dump slope was used to carry out the study of the acoustic emission characteristics of the slope instability dynamic response of the dump slope under the action of vibration, and to quantitatively analyse the staged characteristics of the acoustic emission parameter evolution of the dump slope under the action of different vibration frequencies and its instability initiation node. The results show that with the increase of vibration frequency, the damage mode of the slope model gradually changes from sliding of small particles to large-scale landslides, and presents the stage process of "vibration compaction → vibration equilibrium → dynamic instability"; Under the action of low-frequency and high-amplitude, the slope model mainly shows that the tiny particles and the basement gravel slip, which is difficult to capture with the naked eye, while under the action of high-frequency and low-amplitude, the slope surface is damaged in a large area, and the overall model is unstable; The dynamic instability of the waste dump slope is accompanied by obvious acoustic emission activities, and the changes of the characteristic parameters of acoustic emission reveal, to a certain extent, the evolution of the internal state of the slope in the process of dynamic instability of the waste dump slope and its stage characteristics; The amplitude and energy efficiency of acoustic emission in the time domain show obvious fractal characteristics in the dynamic instability of the waste dump slope.

Preliminary study on the explosive performance of coal dust and prospects for engineering applications.

This study aims to evaluate the efficiency and energy release characteristics of different types of coal in pulse detonation engines (PDE) to advance the development of deep coal fluidization detonation technology, achieving more efficient and cleaner coal utilization. Using a custom PDE setup, experiments were conducted with four coal types at mass flow rates from 30 to 120 g/s. High-frequency pressure sensors assessed pressure dynamics and detonation wave propagation, complemented by numerical simulations for accuracy.

Impact of civil war on the land cover in Myanmar.

Exploring the response relationship between civil war, population and land cover change is of great practical significance for social stability in Myanmar. However, the ongoing civil war in Myanmar hinders direct understanding of the situation on the ground, which in turn limits detailed study of the intricate relationship between the dynamics of the civil war and its impact on population and land. Therefore, this paper explores the response relationship between civil war conflict and population and land cover change in Myanmar from 2010 to 2020 from the perspective of remote sensing using the land cover data we produced, the open spatial demographics data, and the armed conflict location and event data project.

Research on the quantitative relationship between stress shadow effect of multiple thick and hard key layers and surface subsidence.

For a long time, the management of surface structures such as villages and rivers affected by underground coal mining has been a popular and difficult issue in coal mining. With the further tightening of environmental protection requirements, it has become challenging for some underground coal mines that lack the conditions for filling and grouting to ensure the recovery of coal resources while controlling surface subsidence. Furthermore, many such common issues have emerged in the Yushen and Binchang mining areas of Shanxi Province, as well as in several other coalfields, severely constraining the development of coal energy and ecological environmental protection.

Non-uniform failure mechanism and stability control of mining roadway under deviatoric stress field.

Based on the elastic-plastic theory, the analytical formula of the second invariant J of deviatoric stress at any point around the circular roadway under the non-uniform stress field is derived. The distribution law of J of surrounding rock under the three-dimensional non-isobaric stress field is studied by theoretical analysis and numerical simulation. Combined with the butterfly failure theory of surrounding rock of roadway, the close relationship between the distribution pattern of J and the distribution pattern of plastic zone is found, and the failure mechanism of surrounding rock is revealed.

Characteristics of low-temperature oxidative heating and gas production in coal storage under forced convection: Influencing factors and mechanisms.

Slow oxidation of coal during storage and transportation poses significant risks, making it essential to identify hot spots and understand the heat generation and gas production patterns in coal stockpiles. This study leverages the advantages of adiabatic oxidation experiments, which account for time effects, to accurately describe the low-temperature oxidation process of coal through warming and gas production dimensions. Additionally, the warming and gas production patterns of three-dimensional coal stockpiles with varying stacking parameters were investigated.

Effect of Oxygen Concentration on Volatile Precipitation and Critical Ignition Point.

The purpose of this study was to investigate the impact of the oxygen concentration on the ignition of bituminous coal. Different oxygen concentrations and temperatures were used in the large-scale oxidation experiments to collect oxidized coals, which were then extracted with chloroform. And compare the critical ignition temperature of different mass samples.

Synergic Cellulose Nanofiber/Tourmaline Nanoparticle-Assembled Layered Piezoelectric Cryogels for High-Performance Airborne Particulate Filtration.

Here, hybrid stimuli-responsive (exhibiting pyroelectricity and piezoelectricity) porous cryogels are engineered by embedding tourmaline nanoparticles (TNs) in a cellulose nanofiber (CNF) skeleton to generate high-performance CNF-TN-based airborne particulate matter (PM) filters. First, single-layer hybrid cryogels with varying TN contents (0-5% w v) are assembled, and the design principles for multilayered filters are established based on a novel sequential pre-freezing and freeze-drying technique. As observed, the embedded TNs transformed the CNF network into a more homogeneous, isotropic, and firm structure, thus improving the structural integrity and thermal stability of the assembled cryogels while maintaining their ultrahigh porosity and low density.

An investigation into the zoning of ecosystem sensitivity control areas in Mentougou District (Beijing, China).

To achieve a more precise delineation of ecosystem sensitivity control areas, this study examines the Mentougou District in Beijing and introduces the Ecosystem Sensitivity Control Area Classification Method (ESCACM). This novel approach combines single-factor sensitivity analysis, multi-factor comprehensive sensitivity assessments, and strategies for zoning based on various ecological scenarios. The study categorizes the region into three specific zones: first-level management and control areas, second-level management and control areas, and non-management and control areas.

A cost-effective Ca-doped LiZrCl halide solid electrolyte for all-solid-state lithium batteries.

A cost-effective Ca-substituted LiZrCl solid electrolyte (SE) was fabricated by the mechanochemical method, exhibiting high Li conductivity, a wide electrochemical window and excellent compatibility with 4 V-class cathodes. The assembled all-solid-state battery with LiCoO achieves a high cycling performance for 150 cycles at 1C with a high-capacity retention of 83.1%.

Enhanced path tracking control of hydraulic support pushing mechanism via adaptive sliding mode technique in coal mine backfill operations.

The hydraulic support pushing mechanism is the primary equipment utilized in coal mine backfill operations, playing a crucial role in enhancing filling efficiency, ensuring a stable filling body, and managing gob safety. This paper focuses on analyzing the dynamic model and the interrelationship of the hydraulic cylinder, which serves as the power source for the pushing mechanism. To address the intricate coupling effects arising from the hydraulic cylinders and the displacement-force induced by the shared pump, this study employs feedforward compensation for decoupling analysis.

An Investigation of Extended-Dimension Embedded CKF-SLAM Based on the Akaike Information Criterion.

Simultaneous localization and mapping (SLAM) faces significant challenges due to high computational costs, low accuracy, and instability, which are particularly problematic because SLAM systems often operate in real-time environments where timely and precise state estimation is crucial. High computational costs can lead to delays, low accuracy can result in incorrect mapping and localization, and instability can make the entire system unreliable, especially in dynamic or complex environments. As the state-space dimension increases, the filtering error of the standard cubature Kalman filter (CKF) grows, leading to difficulties in multiplicative noise propagation and instability in state estimation results.

Cognitive Response of Underground Car Driver Observed by Brain EEG Signals.

In auxiliary transportation within mines, accurately assessing the cognitive and response states of drivers is vital for ensuring safety and operational efficiency. This study investigates the effects of various vehicle interaction stimuli on the electroencephalography (EEG) signals of mine transport vehicle drivers, analyzing the cognitive and response states of drivers under different conditions to evaluate their impact on safety performance. Through experimental design, we simulate multiple scenarios encountered in real operations, including interactions with dynamic and static vehicles, personnel, and warning signs.

Intelligent Identification and Prediction of Roof Deterioration Areas Based on Measurements While Drilling.

During roadway excavation, the presence of roof deterioration zones, such as layered spaces and weak interlayers, significantly affects the stability of the surrounding rock. To achieve timely and effective support for roadways, it is essential to utilize drilling measurement signals obtained during the construction of anchorage holes for the identification and prediction of these deterioration zones. This study systematically investigates the response characteristics of thrust, torque, and Y-direction vibration signals to different combinations of rock layers through theoretical analysis, laboratory experiments, ABAQUS dynamic numerical simulations, and field measurements.

Influence of Particle Rotation on the Shear Characteristics of Calcareous-Sand and Silica-Bead Granular Materials.

The shear strength and resistance of granular materials are critical indicators in geotechnical engineering and infrastructure construction. Both sliding and rotation influence the energy evolution of soil granular motion during shear. To examine the effects of particle rotation on shear damage and energy evolution in granular systems, we first describe the transformation of irregularly shaped particles into regular shapes via geometrical parameters, ensuring the invariance of energy density and density.