Pressure Patterns Research Articles

Trends in incidence, metastasis, and mortality from thyroid cancer in the USA from 1975 to 2019: a population-based study of age, period, and cohort effects.

In the USA, the incidence of thyroid cancer increased rapidly for several decades, although some studies have suggested that it has now plateaued or even begun to decrease. We aimed to establish whether incidence in the USA has truly decreased or merely plateaued, and to understand some of the underlying factors driving these changes. We conducted a retrospective, population-based study using the National Cancer Institute (NCI)'s Surveillance, Epidemiology, and End Results database and the National Center for Health Statistics database. We used incidence data from these registries obtained between 1975 and 2019, including patients with a diagnosis of thyroid cancer according to the third edition ICD for Oncology (site code C73.9) and malignant histology. We used the NCI's Joinpoint Regression Program to estimate trends in the incidence over time and age-period-cohort modelling to identify the factors influencing these trends. Our sample included 91 968 patients with thyroid cancer, of whom 23 467 (25·5%) were men and 68 501 (74·5%) were women. The annual incidence of thyroid cancer increased from 5·0 cases per 100 000 people in 1975 to 14·6 cases per 100 000 people in 2009, before plateauing until 2019. The age-period-cohort analysis suggests that the changes in incidence were primarily due to time period effects. Furthermore, the increase in incidence was most prominent among women aged 40-69 years and men aged 50-79 years. Throughout all time periods, incidence increased with each successive birth cohort among both women and men. The rise and subsequent plateau in the incidence of thyroid cancer in the USA have been primarily driven by time period effects, likely due to changing patterns in diagnostic pressure. Variations in the incidence of thyroid cancer by age, which increased during the time frame of this study, seem to be driven predominantly by overdiagnosis. Although the incidence of thyroid cancer has plateaued, it remains at peak levels, suggesting that overdiagnosis remains a crucial unresolved public health issue. Further work is needed to help limit the current drivers of overdiagnosis and to implement novel solutions aimed at both physicians, patients, and policy makers. None.

Pressure responses and acoustic emission characteristics during simultaneous and sequential propagation of multiple hydraulic fractures in shale

Deep shale gas reservoirs in the southern Sichuan Basin feature well-developed geological discontinuities, including bedding planes and natural fractures. The interaction between Hydraulic fractures (HFs) and these weak planes can cause complex pressure responses and microseismic event patterns during multi-fracture propagation. This study introduces a novel experimental method for multi-stage and multi-cluster hydraulic fracturing in a horizontal well. The simultaneous and sequential HF propagation are analyzed by integrating real-time injection pressure monitoring and acoustic emission (AE) event localization. Characteristic pressure and AE response patterns are identified for different HF propagation behaviors. Results show that multi-cluster HFs within a stage may not initiate simultaneously, with multiple pressure peaks and each associated with high-energy AE events. The initiation pressure and AE energy of previously initiated clusters are higher than those of subsequently initiated clusters. For multi-fracture sequential propagation, subsequent HFs may initiate at an angle to the wellbore due to the stress shadow from previous fractures, eventually coalescing with them. Moreover, under poor cementing quality, longitudinal HFs may initiate and the injection pressure decreases slightly after peak pressure, followed by a gradual increase with weak fluctuations. The pressure drops when the HF crosses a natural weak plane, with high-energy AE events generated at the intersection and low-energy events distributing along the weak plane. When the fracturing fluid seeps along natural discontinuities, the pressure curve fluctuates intensely and periodically, with low-energy AE events along the weak plane. The conclusions provide a guidance for evaluating fracture geometries through interpreting operation pressures and microseismic monitoring results.

A Comprehensive Review on Nanoparticles as Drug Delivery System and Their Role for Management of Hypertension.

The current global epidemic of hypertension is not a disease in and of itself but rather a significant risk factor for serious cardiovascular conditions such as peripheral artery disease, heart failure, myocardial infarction, and stroke. Although many medications that work through various mechanisms of action are available on the market in conventional formulations to treat hypertension, these medications face significant difficulties with their bioavailability, dosing, and associated side effects, which significantly reduces the effectiveness of their therapeutic interventions. Numerous studies have shown that nanocarriers and nanoformulations can minimize the toxicity associated with high doses of the drug while greatly increasing the drug's bioavailability and reducing the frequency of dosing. This review sheds light on the difficulties posed by traditional antihypertensive formulations and highlights the necessity of oral nanoparticulate systems to solve these issues. Because hypertension has a circadian blood pressure pattern, chronotherapeutics can be very important in treating the condition. On the other hand, nanoparticulate systems can be very important in managing hypertension.

Study on the mechanism and control of strong ground pressure in the mining of shallow buried close-distance coal seam passing through the loess hilly region

Shallow buried close-distance coal seam (SBCCS) is widely found in northern Shaanxi, China. In the process of mining under the loess hilly area (LHA) in SBCCS, many accidents of strong ground pressure have occurred. Taking the in the Zhangjiamao Coal Mine as the background, this study revealed the mechanism of high ground pressure when the working face of lower coal seam passes through the surface loess hilly region. On-site measurements, physical similarity simulation, numerical calculation, and theoretical analysis were combined to study the mining process of SBCCS. The movement characteristics of the activated structure of the interval strata of the lower coal seam were analyzed. The dynamic load and the change pattern of the front abutment pressure (FAP) of the support during the loading stage of entering and exiting the loess hilly were determined. A coupled structural mechanics model of the overlying activated voussoir beam and the step voussoir beam rock beam of the interval strata was established, revealing the dynamic loading mechanism of strong ground pressure during passing through the LHA. The results showed that the dynamic load of the working face was the highest in areas affected by the load of the LHA, followed by the load while entering the LHA, the peak value of the FAP in the load-influenced LHA was high, which was approximately 1.12 times that after leaving the load-influenced LHA and 1.61 times that before entering this area. By establishing a mechanical model of the roof coupling structure when entering and exiting the load-influenced LHA, it was revealed that the dynamic load of the support while mining under the goaf in the LHA is mainly due to the synchronous movement of the activated structure of the collapsed roof of the upper coal seam and the interval rock structure. The load in the LHA was transmitted to the interval rock structure through the activated structure, resulting in a high dynamic load on the support. The study concluded that the determination of the support resistance of the working face should be based on the high-period compressive load of the synchronous movement of the roof structure in the LHA. Through the engineering practice of hydraulic fracturing, the roof structure of the interval strata is changed, which can effectively reduce the dynamic pressure disaster of the working face. The research provides a scientific basis for the safe and efficient mining of shallow coalfields, and it provides reference for similar mining.

Contrasting Responses of Ion Concentration Variations to Atmospheric Patterns in Central Himalayan Ice Cores

AbstractWe analyzed the water‐soluble chemical composition of an 81.2‐m‐long ice core collected in 2019 from 6,000 m elevation on a south‐facing glacier in the Nepal Himalaya. The ice core chronology is based on variability in nitrate and calcium ions, which reveal an apparently seasonal periodicity (with winter maxima) throughout the core's length. Two annual boundaries are consistent with the tritium peak representing nuclear tests conducted in 1963 CE and with the spike in sulfate ions due to the eruption of Krakatau in 1883 CE. The ice core spans 145 years from 1875 to 2019 CE. Dating uncertainties due to the layer counting methodology were estimated as year for 1963–2019 CE and years for 1875–1963 CE. Comparison with earlier ice cores drilled on the northern side of the Himalayas revealed that the ion components exhibit inverse correlations with two key climatic indices: the North Atlantic Oscillation and Southern Oscillation Index. Composite analysis of reanalysis climate data suggests that these inverse relationships reflect springtime pressure patterns, which show regional differences between the northern and southern sides of the Himalayan range.

Neurogenic Orthostatic Hypotension in Parkinson Disease-A Narrative Review of Diagnosis and Management.

Background: Neurogenic orthostatic hypotension (NOH) is a significant non-motor manifestation of Parkinson's disease (PD), that substantially affects patient disability and has a powerful impact on the quality of life of PD patients, while also contributing to increased healthcare costs. This narrative review aims to summarize key insights into the diagnosis and management of NOH in individuals with PD. Methods: For diagnosing NOH, a recently introduced and valuable metric is the ΔHr/ΔSBP index. Additional tools, such as autonomic reflex testing and various blood tests, also can be used to help distinguish orthostatic hypotension (OH) from NOH. Results: Treatment strategies for NOH involve both non-pharmacological and pharmacological approaches. As NOH frequently coexists with other abnormal blood pressure patterns (supine hypertension, nocturnal hypertension, and non-dipping hypertension), its treatment can be a challenge for the clinician. Droxidopa and midodrine are the primary pharmacological agents for NOH, though emerging therapies, such as norepinephrine transporter inhibitors, are being investigated. Conclusions: Despite these advancements, further research is needed to better understand the underlying pathophysiology of NOH, enabling more tailored and effective treatment options for individuals with PD.

Study on the foam production characteristics of air self-suction foam generator by jet

Confined space fires could easily cause serious casualties and property damage, and foam is an effective means of preventing confined space fires. The existing foam generator does not have both momentum and foam expansion rate (FER) and is poorly suited to confined spaces. In order to develop a foam generator suitable for confined space fire protection, an in-depth analysis of the physical foaming characteristics of self-suction foam is required, and the structure of the foam generator is optimized accordingly. For this reason, this paper analyzes the foaming characteristics and forming principle of air self-suction foam generator, and simulates and studies the over-current ratio of rectifying orifice plate with the help of Fluent software, (the ratio of the area of the fluid that can pass through the rectifier disk to the vertical cross-sectional area of the fluid flow), the distribution patterns of flow field, pressure, and turbulence intensity inside the foaming machine are determined by the nozzle cavity spacing and mixing cavity diameter. The study demonstrates that water flow is the most effective means of entraining air, and that the contact between the fluid and foam network is most thorough when the overflow ratio of the fan disc () is 0.455, the distance between nozzle cavities (the distance between the nozzle and the closest end face of the foam chamber vertically.) is 200 mm, and the diameter of the mixing chamber () is 260 mm. These conditions are optimal for the foam generator. Experimental verification shows that the device has the strongest air entrainment capability at 0.455. The foam mesh number (), foam mesh spacing (), and number of layers of foam mesh () significantly impact the air self-solution foaming of the jet. These factors influence FER, range (L), foam stacking thickness (), and unfoamed liquid separation rate (γ, Foam solution not involved in the foaming process.), but the magnitude of their effect varies. Considering the four factors affecting foam production performance, the optimal effect is achieved when the foam mesh of 16, the foam mesh spacing of 3 cm, the foam mesh of 2 layers, the distance between the foam mesh and the nozzle is 22 cm and is 0.455. Under these conditions, the foaming ratio (FER) of the jet self-suction foaming machine is 42 times, with L at 13 m, σ at 7 cm, and γ at 0.15 L/s. A device has been developed for long-distance and high FER air self-suction of foam generator, which can significantly assist in fire prevention and extinguishing in confined spaces.

Understanding Efficacy of Using ACEIs and ARBs in Chronotherapeutic Treatment of Hypertension: Which Drug When?

Hypertension, a prevalent global health issue, poses significant risks for morbidity and mortality. The interplay between hypertension and comorbidities like diabetes and chronic kidney disease (CKD) underscores the urgency for effective management strategies. Chronotherapy, aligning medication administration with circadian rhythms, emerges as a promising approach to optimize treatment outcomes. The objective of this study is to assess the safety and efficacy of the use of ACEIs and ARBs in the chronotherapeutic treatment of hypertension. We aim to clarify the influence of circadian blood pressure patterns on the efficacy of medications and investigate the potential of chronotherapy in the management of hypertension by conducting a thorough examination of the existing literature. A literature search spanning from January 1980 to 2023 was conducted using PubMed, Scopus and Google Scholar databases. Search terms included ACE inhibitors, ARBs, chronotherapy, hypertension, and circadian rhythm of blood pressure. Studies investigating the effects of chronotherapy with ACEIs and ARBs in hypertensive patients were analyzed. Chronotherapy offers a personalized approach to hypertension management, leveraging the dynamic nature of circadian rhythms. By administering ACEIs or ARBs at night, the risk of morning blood pressure surges, associated with adverse cardiovascular events, can be mitigated. However, the optimal timing and combination of medications remain areas of ongoing research. Our review highlights the potential of chronotherapy with ACEIs and ARBs as a promising avenue for hypertension treatment. Further research is warranted to elucidate the mechanisms underlying circadian blood pressure regulation and optimize chronotherapeutic strategies. This comprehensive evaluation underscores the need for personalized treatment approaches tailored to individual circadian rhythms for improved hypertension management and reduced cardiovascular risk.

Correlations of the Circadian Rhythmicity of Blood Pressure With Erectile Dysfunction.

Erectile dysfunction (ED) and cardiovascular diseases (CVD) share common pathophysiological mechanisms. This study aimed to assess the relationship between ED and its severity with the risk of developing CVD by analyzing changes in the circadian blood pressure (BP) rhythm. In the study, 24-h BP levels of 192 (94 with ED and 98 controls) participants with no history of CVD were evaluated using an ambulatory blood pressure monitoring (ABPM) device. The International Index of Erectile Function (IIEF) questionnaire was used to assess the ED severity in the study group. ABPM measurements revealed higher BP values among the ED group. The nondipper pattern was significantly more frequent in the ED group compared to the controls (56.2%vs. 77.1%, p<0.01). Blood pressure variability parameters, including systolic standard deviation (SD) and average real variability (ARV), were notably higher in the ED group (16.3±3.9vs. 14.6±4.3, p<0.01 and 13.39±7.24vs. 11.5±2.1, p<0.01, respectively). Furthermore, parameters reflecting arterial stiffness including pulse pressure index (PPI) and ambulatory arterial stiffness index (AASI) were higher in the ED group (0.81±0.33vs. 0.73±0.18, p = 0.03 and 0.71±0.09vs. 0.59±0.17, p = 0.014, respectively). Both AASI and ARV were significantly correlated with the severity of ED. This study suggests a significant association between ED severity and altered blood pressure patterns which in part explains the increased risk of CVD among individuals with ED.

Implications of Wearable Technology for Improved Patient Monitoring and Self-Management in Nursing Practice

The rapid evolution of wearable technology has introduced significant advancements in healthcare, particularly in the realm of nursing practice, where it is reshaping patient monitoring and self-management strategies. Wearable devices—ranging from fitness trackers and smartwatches to specialized health monitors—enable continuous, real-time tracking of a wide range of physiological metrics such as heart rate, blood pressure, glucose levels, and sleep patterns. These devices provide nurses with a comprehensive understanding of patients' health outside traditional clinical settings, offering a more proactive, personalized approach to care. This real-time data empowers both healthcare providers and patients, enhancing patient engagement and facilitating early intervention for chronic disease management. Wearables have shown promise in improving health outcomes by promoting patient self-management, reducing hospital readmissions, and preventing complications associated with conditions like diabetes, hypertension, and cardiovascular disease. However, challenges such as ensuring data accuracy, maintaining patient privacy, addressing device usability, and achieving seamless integration into existing healthcare systems remain significant barriers. This article explores the profound implications of wearable technology in nursing practice, focusing on its potential to improve patient outcomes through enhanced monitoring, data-driven care, and patient empowerment. Additionally, the article discusses the ethical, logistical, and technological hurdles that need to be addressed to maximize the benefits of wearables, and outlines the future possibilities for wearable technologies in advancing healthcare delivery and nursing practice.

Geographical Disparities in Blood Pressure and Dietary Patterns: A Comparative Study of Mountainous and Coastal Communities in Gorontalo, Indonesia

Geographical Disparities in Blood Pressure and Dietary Patterns: A Comparative Study of Mountainous and Coastal Communities in Gorontalo, Indonesia

Key Techniques for the Ultra-Deep Large Flood Diversion Pipeline: A Case Study of Jinshui River Flood Diversion Project in Zhengzhou

The implementation of large-diameter flood diversion pipelines in urban areas serves as an effective strategy to address urban waterlogging issues, which can enhance the resilience of cities to a certain extent against extreme precipitation events. This case study delineates the Zhengzhou Jinshui River flood diversion project, which employs the ultra-large-buried jacking prestressed concrete cylinder pipe (JPCCP), offering a summary and analysis of the pipe design and construction technologies employed in the JPCCP project within collapsible loess stratum, and the study also analyzes the pull-back scheme of the incident involving the front-end sinking of the machine head. Through on-site monitoring experiments, the variation patterns of contact pressure and slurry pressure of large-diameter JPCCPs were analyzed. The results demonstrate that the trends in contact pressure and slurry pressure exhibit a general consistency. During the jacking process, the pressure around the pipe can be categorized into three distinct phases based on grouting frequency or pressure, with notable variations in the pipe–soil–slurry contact state. The difference between the contact pressure and slurry pressure (termed as effective soil pressure) serves as a more accurate method for determining the pipe’s operational state. Moreover, the effective earth pressure at the pipe top demonstrates a higher degree of consistency with the calculation results prescribed by the standards ATV A161 and ASCE 27.

Effect of Foot Insole on Planter Pressure Distribution in Patients with Neuropathic Diabetic Foot Ulcer: A Prospective, Randomized, Double-Blinded, Controlled Clinical Trial.

Background and Objectives: Patients with diabetes polyneuropathy are at a heightened risk for developing foot ulcers, often due to dynamic plantar foot pressure patterns that lead to increased pressure and shear forces in specific foot areas. This study aimed to evaluate the effects of foot insoles on peak pressure and the pressure-time integral in patients with polyneuropathy diabetic foot ulcers over a twelve-week period followed by an eight-week follow up. Materials and Methods: This was a prospective, randomized, double-blinded, controlled clinical trial involving 60 patients aged between 50 and 65 years of both genders. Inclusion criteria included midfoot ulcer grades II or III, a history of polyneuropathy diabetic foot ulcers lasting between six months and one year, diabetes duration of seven to ten years, glycated hemoglobin levels between 7% and 9%, and a body mass index (BMI) ranging from 25 to 30 kg/m2. Participants were randomly assigned to either the study group, which received foot insoles along with medication and wound care, or the control group, which received only medication and wound care. Measurements of peak pressure and pressure-time integrals were taken at the start of this study, after twelve weeks, and again eight weeks post-study. Results: The results indicated significant differences in peak pressure and pressure-time integral measurements for the rearfoot, midfoot, hallux, and both medial and lateral forefoot areas after twelve weeks of using foot insoles compared to the control group. This suggests that the use of foot insoles effectively reduces peak pressure and the pressure-time integral in these critical areas. Conclusions: The findings of this study support the use of foot insoles as a beneficial intervention for decreasing peak pressure and the pressure-time integral on the hallux, medial, and lateral forefoot in patients with polyneuropathic diabetic foot ulcers, and they could play a crucial role in preventing further complications.

Evaluating How Historical Climate Change Affected a Heavy Snowfall Event in Northern Japan in Mid‐December 2021 Using Two Pseudo Global Warming Methods

AbstractIn mid‐December 2021, heavy snowfall occurred when an extratropical cyclone passed around Hokkaido, northern Japan. In this study, we investigated the contribution of historical climate change to the heavy snowfall event using large ensemble simulation data sets and two pseudo global warming (PGW) methods. We classified the large ensemble simulation data sets by the pressure pattern and identified the extratropical cyclone event. Composite analyses reveal that the development of the extratropical cyclone can be attributed to historical climate change. We ran the PGW method with the classified meteorological data as the input data and found that the development of the extratropical cyclone resulted in enhanced water vapor transport and intensified local convergence in the lower troposphere, causing heavy precipitation. We also found that oceanic warming made a minimal contribution to the precipitation in this event. These findings highlight the importance of considering historical changes in event‐specific synoptic‐scale atmospheric conditions when evaluating the contributions of climate change to extreme events.

The condition of target organs in patients with hypertension after new coronavirus infection

Objective. To determine the risk factors for the development of new coronavirus infection (NCVI) in patients with hypertension (AH) and to assess the condition of target organs depending on the course of NCVI. Materials and methods. A screening clinical observational comparative study is presented. For a 2-year period 186 patients with a history of AH or with a first-time BP increase who consulted a general practitioner in an outpatient department were sequentially included into the study in accordance with the inclusion and non-inclusion criteria. The patients were divided into two groups depending on the presence of NCVI: the first group consisted of 100 patients with AH or first-onset AH who had had NCVI; the second group contained 86 patients with AH or first-time AH without a history of NCVI. All patients with AHunderwent a comprehensive routine clinical examination with an assessment of target organ damage in accordance with clinical guidelines within 14 days after visiting the polyclinic with an assessment of the data of the outpatient card and other medical documents to register concomitant diseases and conditions, as well as the features of the course of NCVI. Results. Vaccination against NCVI in patients with AH reduces the relative risk (RR) of the development not only of NCVI by 87 %, but NCVI-pneumonia with hospitalization and prolonged post-COVID syndrome as well. It has been proved that obesity with a body mass index of 30 g/m2, atherosclerosis of any localization, type 2 diabetes mellitus increase the RR of the development of various forms of NCVI, including a prolonged course of more than 12 weeks. Newly diagnosed chronic heart failure (CHF), verified not only by clinical symptoms, but also by echocardiography and N-terminal fragment of brain natriuretic propeptide (Nt-proBNP) concentration in the blood, increases the RR of the development of NCVI by 48.2 %, NCVI- pneumonia with hospitalization, and the prolonged course of NCVI by more than 2 times. An increase in Nt-proBNP 125 pg/ml in patients with AH even without CHF is associated with the development of various forms of NCVI, including post-COVID syndrome. The use of renin-angiotensin-aldosterone system (RAAS) blockers, dual combined antihypertensive therapy in patients with AH reduced the RR of the development of both NCVI, NCVI-pneumonia with hospitalization and the prolonged course of NCVI on an average by 30 to 50 %. The use of sulfonylureas and/or insulin therapy in patients with AH and type 2 diabetes mellitus was associated with an increase in the RR of the development of NCVI by 73.6 %, the RR of the development of NCVI-pneumonia with hospitalization was more than 4 times higher, and a prolonged course of NCVI almost 3 times higher. Average daily pulse blood pressure and abnormal patterns of circadian rhythm of SBP and DBP were associated with an increase in RR of both acute and chronic forms of long-term NCVI. NСVI- pneumonia with hospitalization and post-COVID syndrome are associated with an increase in the RR of pathological changes in all target organs in patients with AH in comparison with patients who did not have any complications after NCVI. Conclusion. Known risk factors for the development of various forms of NCVI, including its prolonged course in patients with AH, have been confirmed and new ones have been revealed. It has been determined that NCVI with a severe course and post-COVID syndrome are associated with pathological changes in all target organs in patients with AH after NCVI.

Blood pressure patterns in pressurometry and their ralationship with cardiovascular events in follow-up

Nuestro objetivo fue determinar en una cohorte de pacientes de un hospital de la ciudad de Buenos Aires, cómo fue la distribución de ritmo circadiano y el impacto según el tipo de comportamiento circadiano en la tasa de eventos cardiovasculares en el seguimiento. Material y métodos: Estudio de cohorte retrospectiva que incluyó pacientes adultos que se realizaron una presurometría ambulatoria en un hospital de la ciudad de Buenos Aires, incorporados a un registro propio entre marzo de 2017 y julio de 2020, con seguimiento de hasta 36 meses de la presurometría índice. De 522 sujetos, se incluyeron 494 en el análisis final. El 48% eran de sexo masculino y la edad promedio fue de 58,9 años. El 62% (n = 308) presentó hipertensión arterial nocturna. El patrón dipper invertido fue el grupo que presentó más eventos cardiovasculares en el seguimiento (6% n: 24). Además, en el tiempo libre de evento globales, se evidencio menos tasas de supervivencia para el grupo con patrón dipper invertido (Log Rank test p: 0.0033). En una cohorte contemporánea y de la ciudad de Buenos Aires, el grupo patrón dipper invertido se asoció con la aparición de desenlaces cardiovasculares. En base a estos hallazgos, se deben implementar medidas para incrementar su diagnóstico en nuestro medio.

Spatiotemporal evolutions of gas pressures in coal seam during gas extraction under mining disturbance

A 3D geometric model is established based on a fluid‒solid coupling model for purpose of identifying the influences of mining disturbances on the distribution of gas pressures in front of a working face during gas extraction. Then, the stress distribution and gas extraction process are simulated using COMSOL software. The spatiotemporal evolutions of gas pressures in front of the working face are analyzed from the dimensions of point, line, surface, and volume. A comparative analysis has been conducted to explore the distribution patterns of gas pressure in fractures and pores. The results show that under mining disturbance, the stresses in front of the working face create a stress-relaxation area, a stress concentration area, and an original stress area. Moreover, a low stress concentration is located near the boreholes. In the early stage of gas extraction, corresponding to the stress distribution, the gas pressures present a depressurization area, pressure concentration area, and almost undisturbed area. As the time increases after mining, the effects of mining disturbances gradually decrease, and the range of the gas pressure concentration area steadily shortens and shifts toward the front of the working face. Under the same temporal conditions, the gas pressure in pores is higher than that in fractures. At the onset of mining, the pore gas pressure is even greater than the initial pressure. Furthermore, during the identical extraction period, the “concentration area” of pore gas pressure is situated farther away from the coal wall of the working face compared to the “concentration area” of fracture gas pressure. These results of the study provide theoretical support for arranging drainage boreholes, enhancing gas extraction efficiency, safeguarding against gas accidents.

Pressure characteristics and force analysis of pump turbine in variable-pressure outlet pump mode

A nonstationary numerical simulation was performed on the outlet pressure stabilization and periodic variable-pressure condition of a pump turbine model in the pumping condition. The objective was to dissect the flow mechanism and force characteristics of components within the outlet variable-pressure pumping condition of the pump turbine and to probe into the stability of the pump turbine under such working conditions. Additionally, the alterations in the runner state, pressure distribution, pressure pulsation, as well as the forces exerted on the runner and top cover during this process were analyzed. The results demonstrated that the internal pressure and flow pattern of the pump turbine under variable-pressure conditions fluctuated periodically in accordance with the outlet pressure. An augmented frequency of the outlet pressure variation led to an elevation in the amplitude of the internal pressure change. Nevertheless, a hysteresis difference was observed in the changes of the flow channel pressure and flow pattern. The pressure pulsation in the runner area was influenced by the runner rotation, static and dynamic interferences in the lobe-free area, and the unsteady flow induced by the alterations in the outlet pressure.

Analyzing the Correlation Between Plantar Pressure Distribution and UTAH Back Compressive Force and NIOSH Lifting Index in Symmetrical Lifting Tasks

Introduction: Lifting loads in awkward postures is a main cause of low back musculoskeletal disorders. In this context, researchers have used various indicators to determine the relationship between biomechanical variables and the risk of these disorders. This study aimed to investigate the correlation between plantar pressure distribution and the values of UTAH back-compressive forces (BCF) and lifting index (LI) during symmetrical load-lifting tasks. Material and Methods: Thirteen healthy men, aged 25 to 35, took part in this study. The participants were instructed to symmetrically lift loads weighing 7.5 kg and 15 kg in 15 different postures, considering three horizontal distances (A, B, C) and five different heights (1-5). Pressure on the foot soles was recorded using 16 force-sensitive resistors (FSR) corresponding to eight anatomical areas on each foot. The BCF and LI were also calculated using the UTAH method and the NIOSH equation, respectively. Statistical analysis was performed using SPSS (version 21) software. Results: Based on the results, when the load was closest to the body (A1-A5), the highest pressure was recorded in the heel and the 4th and 5th metatarsal of both feet. In lifting a load of 15 kg in the A2, B1, B2, C1, C2 postures and lifting a load of 7.5 kg in the C2 posture, the average BCF exceeded 700 pounds. The LI was greater than 1 for specific postures (B1, B2, B4, B5, C1-C5) at 15 kg and (C1, C2, C4, C5) at 7.5 kg load-lifting. During the 7.5 kg and 15 kg load-lifting, there was a significant correlation between the plantar pressure and the values of LI and UTAH (p-values &lt; 0.05) in most postures. Conclusion: The results showed a significant correlation between plantar pressure distribution and load- lifting postures. The study findings, which identify risk levels associated with lifting postures, lay the groundwork for future research aimed at categorizing safe and unsafe plantar pressure patterns

Data-driven macro-scale simulation for rapid electrolyte wetting in lithium-ion batteries

Data-driven macro-scale simulation for rapid electrolyte wetting in lithium-ion batteries