High Pressure Research Articles

A Physics Informed Neural Network for Solving the Inverse Heat Transfer Problem in Gas Turbine Rotating Cavities

Abstract Recently, Physics-Informed Neural Networks have displayed great potential in delivering swift and accurate solutions for inverse problems. Here, a Physics-Informed Neural Network (PINN) was used to solve the inverse heat conduction problem in the rotating cavities of a aeroengine high-pressure compressor internal air system. The neural network was designed to receive experimentally captured radially distributed temperature profiles as inputs and predict the associated surface heat fluxes. The correctness of these predicted heat fluxes are assessed by numerically solving the direct heat conduction equation using a 2D Finite-Element model, thereby recovering the original temperature profiles. A comparative analysis is conducted between the predicted temperature profiles and the initial inputs. The physics informed neural network is trained using noise free synthetic data, created from a range of radial temperature curve fit coefficients, and subsequently tested on noisy experimental data at engine representative conditions. The predicted temperature values exhibit some good agreement with their respective actual counterparts. Furthermore, the sensitivity of model hyperparameters are explored to showcase the capability of the proposed approach. The results show that Physics- Informed Neural Networks exhibit reduced susceptibility to experimental uncertainties when addressing inverse problems, in contrast to inverse solution methods, and offer a possible new approach for analysis of experimental data if trained on a sufficiently large dataset.

Spontaneous breathing-induced lung injury in mechanically ventilated patients

Purpose of review Recent experimental and clinical studies have suggested that spontaneous effort can potentially injure the lungs. This review summarizes the harmful effects of spontaneous breathing on the lungs during mechanical ventilation in ARDS and suggests potential strategies to minimize spontaneous breathing-induced lung injury. Recent findings Recent clinical and experimental studies have shown that vigorous spontaneous breathing during mechanical ventilation can potentially injure the lungs due to high transpulmonary pressure, the Pendelluft phenomenon, increased pulmonary perfusion, and patient–ventilator asynchrony. A definitive approach to minimize spontaneous breathing-induced lung injury is the systemic use of neuromuscular blocking agents; however, there is a risk of muscle atrophy. Alternatively, partial paralysis, bilateral phrenic nerve blockade, and sedatives may be useful for decreasing force generation from the diaphragm while maintaining muscle function. A higher positive end-expiratory pressure (PEEP) and prone positioning may reduce force generation from the diaphragm by decreasing neuromechanical efficiency. Summary Several potential strategies, including neuromuscular blockade, partial paralysis, phrenic nerve blockade, sedatives, PEEP, and prone positioning, could be useful to minimize spontaneous breathing-induced lung injury.

Lifestyle intervention improves cardiometabolic profiles among children with metabolically healthy and metabolically unhealthy obesity

BackgroundIn recent years, there has been a surge of interest in the metabolic phenotype among children with obesity characterized by the absence of associated cardiometabolic risk factors (CRFs), known as metabolically healthy obesity (MHO), as opposed to those with metabolically unhealthy obesity (MUO). This study investigated the effect of lifestyle intervention on CRFs among children with MHO and MUO.MethodsA total of 102 school-aged children with obesity (54 girls and 48 boys) aged 8–16 years completed a 16-week school-based lifestyle modification intervention program, MyBFF@school Phase I. The intervention consisted of physical activity, healthy eating promotion, and psychological empowerment. MHO and MUO statuses were defined based on the 2018 consensus-based criteria. Fasting venous blood collection, body composition measurement, clinical assessment and physical fitness testing were conducted at baseline and at the end of week 16.ResultsAfter the intervention, the CRFs of the children with MUO improved with significant decreases in systolic (p < 0.001) and diastolic (p = 0.01) blood pressure and a significant increase in high-density lipoprotein cholesterol (HDL-C) (p = 0.005), while the CRFs of the children with MHO had a significant decrease in uric acid (p = 0.04). Additionally, 51.6% of the children with MHO transitioned to the MUO, while 26.8% of the children with MUO crossed over to the MHO at the end of the intervention. Furthermore, the odds of having high systolic blood pressure among children with MUO were 59% lower at week-16 than at baseline (OR = 0.41 (95% CI = 0.18, 0.92), p = 0.03).ConclusionsOur findings demonstrated that CRFs improved more prominently among children with MUO following the intervention. More importantly, our findings indicate that MHO in children is transient, hence, strategies to protect children against MUO are warranted.Trial registration: ClinicalTrials.gov NCT02212873.

Pressure-tolerant survival mechanism of Schizophyllum commune 20R-7-F01 isolated from deep sediments 2 kilometers below the seafloor

In anaerobic high hydrostatic pressure (HHP) sedimentary environments below the seafloor, fungi are found to dominate the eukaryotic communities, playing crucial ecological roles. However, the specific mechanisms by which fungi adapt to anaerobic HHP environments remain unclear. In this study, we investigated Schizophyllum commune 20R-7-F01 isolated from coal-bearing sediments at a depth of 2 km below the seafloor. By assessing the cell viability, biomass, and cell wall thickness changes of strain 20-7-1 under different HHP conditions, we observed that, compared to 0.1 MPa, strain 20-7-1 exhibited slower growth rates and decreased cell viability at 15 MPa and 35 MPa, yet demonstrated significant pressure tolerance. Transcriptomic and metabolomic analyses revealed that this strain activated the carbohydrate metabolic process to simultaneously utilize ethanol and lactic acid fermentation pathway. Additionally, it activates the oxidoreductase activity and hydrolase activity pathways to detoxify intracellular reactive oxygen species (ROS). Activation of the metal ion binding pathway increases the proportion of unsaturated fatty acids in the cell membrane, while instigation of the integral component of membrane pathway maintains cell wall structural stability. Furthermore, activation of the DNA repair pathway repairs DNA damage, demonstrating its comprehensive adaptive mechanisms against the HHP stress. These research findings deepen our understanding of fungal survival strategies and adaptation mechanisms in extreme environments, laying the groundwork for further exploration of their roles in cycling of carbon, nitrogen, sulfur, and other elements in the deep biosphere.

Artificial Intelligent Branching Simulations (AIBS) in Critical Care Neonatal Nursing

Roleplaying, simulations and branching scenarios are among the most authentic, critical and effective educational experiences, though have seen limited adoption due to the expense of creating, staffing, adapting and sustaining them over time (Davies, 2013). The new generation of large language models have made possible new affordances that enable delivering scenario based roleplaying experiences more sustainably. This Pecha Kucha charts the development process, frontier technology and the positive outcomes of an artificial, intelligent branching simulation (AIBS) a in critical care neonatal nursing simulation. Critical care disciplines and nursing have a tradition of using expensive in-person simulations and labor-intensive, high-stress scenarios to prepare students for the workplace (Jefferies, 2020). After such training, nurses undergo rigorous, high pressure in-person evaluations, such as the ANSAT (Ossenberg, Mitchell &amp; Henderson, 2020), which they must pass in order to practice. Foundational reading about nursing practices and reviewing practice manuals is a step towards passing such evaluations, but these more theoretical learning practices don’t constructively align with the situational, authentic skills that are demanded in practice. With few learning experiences that can scaffold towards critical in-person evaluation, students often report high levels of anxiety and that they feel inadequately prepared for in-person evaluation, sometimes failing and leaving their studies and aspirations entirely (Cornine, 2020). Mindful also of an industry wide shortage of critical care nurses, there is a clear need to find bridging solutions that can affordably and effectively prepare trainee nurses for demanding in-person workplace evaluations. This Pecha Kucha charts the development of AIBS that was designed to bridge a learning gap between more theoretical training methods and high stress in-person training evaluations. The increasing popularity of conversational agents powered by large language models on web-based platforms like Character.ai (Sarkar, 2024), suggests that students might find a chatbot an approachable, engaging and an increasingly familiar experience. Initial tests directly prompting ChatGPT and Claude.ai both showed promise, but also raised some issues around reliability which mandated more direct and qualified oversight of teaching staff. A technical solution was required as an intermediary between the students and the LLMs that enabled ‘human-in-the-middle’ (Mollick, 2024) oversight. After an extensive review, the educator created tool ‘Cogniti’ was selected due to it’s ability to provide a seamless, pretrained scenario chat experience, while also enabling student account integration, data governance, supervisor oversight and privacy controls. The prompts used to instruct the Cogniti AI agent were developed using the RTRI prompting framework (Lui 2023, Hardman, 2023). By separating parts of the scenario into sequential chunks, each with a series of ‘expected responses’ it became possible to create and align an improvisational prompting script that resembled a sequence from a typical hospital procedures manual and that aligned to the prescribed ANSAT placement evaluation framework (Ossenberg, Mitchell &amp; Henderson, 2020). Allocating specific roles to the AI agent and to the trainee nurse within a framework of expected responses enabled the narrative to resemble an authentic interaction, but within a safe environment. Prompting the AI agent to progress the narrative under specific conditions and to provide structured feedback to students, enabled a cohesive educational experience that was able to address specific gaps in student knowledge of neonatal practice and procedure. Staff and student feedback demonstrated positive results in terms of engagement, satisfaction, academic performance and student well-being.

Soft‐Actuated Cuff Electrodes with Minimal Contact for Bidirectional Peripheral Interfaces

AbstractNeural interfaces with embedded electrical functions, such as cuff electrodes, are essential for monitoring and stimulating peripheral nerves. Still, several challenges remain with cuff electrodes because sutured devices can damage the nerve by high pressure and the secured contact of electrodes with the nerve is hard to accomplish, which however is essential in maintaining electrical performance. Here, a sutureless soft‐actuated cuff electrodes (SACE) that can envelop the nerve conveniently by creating a bent shape controlled upon fluid injection, is introduced. Moreover, fluid injection protrudes part of the device where electrodes are formed, thereby achieving minimized, soft but secure contact between the electrodes and the nerve. In vivo results demonstrate the successful recording and stimulation of peripheral nerves over time up to 6 weeks. While securing contact with the nerve, the implanted electrodes can preserve the nerve intact with no reduction in blood flow, thereby indicating only minimal compressive force applied to the nerve. The SACE is expected to be a promising tool for recording and stimulation of peripheral nerves toward bidirectional neuroprostheses.

Assessing the impact of telemedicine interventions on systolic and diastolic blood pressure reduction: A systematic review and meta-analysis

Background Hypertension, characterized by high blood pressure, poses a significant risk for cardiovascular diseases, stroke, and heart attack. Managing it is particularly challenging in areas with limited healthcare access and for patients who cannot attend regular in-person visits. Telemedicine interventions offer a promising solution by improving patient adherence and facilitating timely treatment adjustments. This study aims to systematically evaluate the impact of these telemedicine interventions on reducing systolic and diastolic blood pressure. Methods A comprehensive search of PubMed, Scopus, and Web of Science was conducted to identify relevant studies. Two independent reviewers screened and selected eligible articles, extracting key data using a standardized form. The quality of the included studies was assessed with the Mixed Methods Appraisal Tool (MMAT). A random effects model was used to combine the results, with treatment effects measured using standardized mean differences (Hedges's g). Consistency of findings was evaluated through statistical tests, including the Q test and I² statistic, to assess heterogeneity. Data analysis was conducted using Stata statistical software version 17.0. Results Of the 2700 articles retrieved, 35 studies were selected for inclusion in the analysis. Using a random-effects model, the overall effect size was Hedges's g = −0.22 (95% CI: −0.30 to −0.15; p-value &lt; 0.001), indicating a small but meaningful reduction in blood pressure (systolic and diastolic). Telemedicine interventions had a greater impact on systolic blood pressure (Hedges's g = −0.27, 95% CI: −0.39 to −0.15; p-value &lt; 0.001) compared to diastolic blood pressure (Hedges's g = −0.17, 95% CI: −0.26 to −0.07; p-value &lt; 0.001), though both reductions were clinically relevant. Conclusion This study demonstrates that telemedicine interventions significantly reduce both systolic and diastolic blood pressure, with a more pronounced effect on systolic pressure. The overall effect size indicates a small but meaningful improvement in hypertension management. These findings highlight the potential of telemedicine as an effective strategy for enhancing patient outcomes in hypertension care.

Successful Management of High-Risk Pregnancy with TORCH Infection History and Chronic Hypertension

A 41-year-old pregnant woman of Javanese ethnicity attended the outpatient clinic of a private hospital, presented with fifth pregnancy and no living children due to a history of ectopic pregnancy, two times IUFD, and one time neonatal death. The patient also had a history of chronic hypertension and asthma. The examination showed positive IgG Toxoplasma and CMV antibody levels. The patient's blood pressure also never touched the normal limit since the beginning of pregnancy. At the end of pregnancy, she had very high blood pressure and proteinuria. According to WHO Maternal Mortality Rate (MMR) is still very high, where two of the five highest causes are infection and hypertension in pregnancy. High risk pregnancies require special attention in monitoring during pregnancy and management. In a history of bad obstetrical history it is necessary to screen for infection which can be done by antibody serology testing. A positive IgG indicates immunity to the virus, if possible it is necessary to check IgG Avidity to determine whether therapy is still needed or can rely on the immune system that has been formed. Chronic hypertension (Systolic Blood Pressure (SBP) &gt; 140 mmHg and / or Diastolic Blood Pressure (DBP) &gt; 90 mmHg since &lt; 20 Weeks Gestational Age (WGA) until 42 days after delivery). First-line Labetalol and Nifedipine or second-line Methyldopa and Hydrochlorothiazide should be considered depending on the condition and gestational age. If there are signs of preeclampsia, termination should be done if possible, along with antihypertensives and anticonvulsants such as MgSO4.

A ATUAÇÃO DO FISIOTERAPEUTA NA SAUDE DO IDOSO HIPERTENSO

According to the WHO, in 2050 the number of elderly people aged 60 and over will exceed the number of total children aged zero to 14 years old. Arterial hypertension (technical term) or high blood pressure (term used by the lay public) is a chronic disease that often affects elderly people, characterized by high levels of blood pressure in the arteries. It occurs when the maximum and minimum pressure values are equal to or exceed 140/90 mmHg (or 14 by 9) The objective of the Physiotherapy professional is to assist in the prevention of diseases or mainly in the care of patients with SAH, promoting quality of life, independence and improving the daily life of the elderly. Care needs to be provided or better applied so that this high population population follows a path where morbidity and mortality do not increase as a result of the health of the elderly.

Supporting GPs and people with hypertension to maximise medication use to control blood pressure: a pilot cluster RCT of the MIAMI intervention

BackgroundHypertension, or high blood pressure, is a key modifiable risk factor for heart disease and stroke. International guidelines have highlighted ‘poor adherence to treatment’ and ‘physician inertia’ as major barriers to effective blood pressure management. The Maximising Adherence, Minimising Inertia (MIAMI) intervention, a theory-based complex intervention, supports General Practitioners (GPs) and people with hypertension in maximising medication use to manage blood pressure. This pilot cluster randomised control trial (RCT) aimed to collect and analyse feasibility data to refine the MIAMI intervention and assess the feasibility of a definitive RCT.MethodA pilot cluster RCT with a MIAMI intervention arm and usual care control arm was conducted. Quantitative data collection consisting of clinical measures and a self-report questionnaire took place at baseline and twelve week follow up. Semi-structured interviews with GP and patient participants were conducted. Fidelity (as measured by a protocol checklist and through qualitative interviews) and health economics costings were assessed.ResultsSix GP practices (intervention arm n = 3, control arm n = 3) and 52 patients (intervention arm n = 25, control arm n = 27) took part. All six GP practices and 92% of patients were retained. Fidelity, as measured by a checklist and through qualitative interviews, was good but three deviations from protocol were identified. Outcomes and measures used were acceptable. The implementation cost of the MIAMI intervention was estimated at €490 per participant. The qualitative data demonstrated that the intervention was considered acceptable and feasible by both GP and patient participants, except for the urine test component, which GPs found difficult to incorporate into practice due to logistical challenges.ConclusionsThe MIAMI intervention was considered largely acceptable and feasible. Some changes to both intervention components and trial processes are required but with these in place a definitive RCT could be considered worthwhile.Trial registrationISRCTN registry, ISRCTN85009436, registered 17/1/23.

EFFECTS OF HEALTH EXPENDITURE ON FOOD SECURITY STATUS OF RURAL HOUSEHOLDS IN OGUN STATE, NIGERIA

The study assessed the effect of health expenditure on the food security status of rural households in Ogun State, Nigeria. Multistage sampling procedure was used to select 120 rural households in the study area. Data was collected from the respondents with the aid of a semi-structured questionnaire complemented with an interview guide. Descriptive statistics, food security index, cost of illness procedure and binary logit regression model were the analytical techniques used for data analysis. Findings from the study revealed that majority (79.2%) of the respondent were male, married (90.8%), with a mean household size of 5 persons. Also, the mean age of the respondents was found to be 54 years with most of them involved in farming as their major occupation. Findings also revealed that majority of the rural households suffered from various illnesses such as malaria, waist/back pain, fever, high blood pressure, rheumatism and other illnesses with an average estimated cost of illness (₦45, 973.68 per month). The results of the food security status of the rural households revealed that a higher percentage (53.3%) of the rural households were food insecure. Factors found to significantly affect the food security status of the rural households were cost of illness (p&lt;0.1) and other socio-economic variables such as education (p&lt;0.1), income (p&lt;0.05) and sex of the household head (p&lt;0.01). Therefore, this study recommends that government should subsidize the cost of drugs and other medical expenses for poor households particularly those in the rural areas in order to reduce their financial burden on health care and increase their economic access to food.

Investigating the role of thrombosis and false lumen orbital orientation in the hemodynamics of Type B aortic dissection

While much about the fundamental mechanisms behind the initiation and progression of Type B aortic dissection (TBAD) is still unknown, predictive models based on patient-specific fluid-structure interaction (FSI) simulations can help in risk stratification and optimal clinical decision-making. Aiming at the development of personalized treatment, FSI models can be leveraged to investigate the interplay between complex aortic flow patterns and anatomical features, while considering the deformation of the arterial wall and the dissection flap. In this study, the hemodynamics of false lumen thrombosis, a large fenestration, and the orbital orientation of the false lumen is studied through image-based FSI simulations on three TBAD patient-specific geometries. A new pipeline is developed leveraging the open-source software SimVascular and ParaView to analyze multiple patients simultaneously and to achieve large-scale parallelization in FSI results based on patients’ computed tomography (CT) images. The results of this study suggest that the internal orbital orientation of the false lumen contributes to maintaining a positive luminal pressure difference ΔPTL-FL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Delta P_{TL-FL}$$\\end{document} = PTL-PFL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$P_{TL}-P_{FL}$$\\end{document} between the true lumen (TL) and the false lumen (FL), despite an impingement area in the false lumen near the entry tear. A positive and high luminal pressure difference is thought to promote TL expansion and FL compression. Moreover, it was also found that FL thrombosis at the entry tear region reduce the magnitude of the negative luminal pressure difference, which in turn may reduce FL expansion and the risk of unstable aortic growth. Finally, this FSI study suggests that the aortic wall and dissection flap stiffness determines the effects of a large fenestration in the descending thoracic aorta on the luminal pressure difference.

Matching Analysis of Technical Parameters and Safety Standards for Nuclear Replacement of Coal-Fired Units

In the context of the growing share of renewable energy and the impending decommission of a large number of coal-fired units, nuclear energy is the only green energy that can replace coal power for a stable, clean, efficient, and large-scale power supply. This article compares the differences between coal power and nuclear power in terms of thermal system, thermal cycle, turbine parameters, and safety. It discusses the possibility of replacing the boiler of a coal power plant with nuclear power, that is, replacing the boiler of a coal power plant with a nuclear reactor for generation/heating/cogeneration. For coal-fired units with similar capacity that do not use a reheat cycle (at or below high pressure) and nuclear power units (such as a high-temperature gas-cooled reactor), as well as coal-fired units with a reheat cycle (ultra-high pressure and above) and nuclear power units (such as pressurized water reactors), there are great differences in steam parameters. In terms of steam turbines, the size of nuclear power units is relatively larger, requiring additional dehumidification measures. In addition, the safety factors and management methods considered in the site selection, construction, and operation of nuclear power plants are more stringent and complex, and comprehensive analysis and evaluation are needed in aspects such as waste treatment and accident emergency response. Except for the relevant provisions of the American Society of Mechanical Engineers code for pressure vessels, nuclear power units are not compatible with coal-fired units in terms of safety standards. Therefore, considering comprehensively, it is believed that the scheme of nuclear power replacing coal-fired units for power generation/heating/cogeneration program is not feasible at present.

Elastic properties of TiS2 material at high pressure by a first-principles DFT approach

Elastic properties of TiS2 material at high pressure by a first-principles DFT approach

Ultrafast dynamics evidence of strong coupling superconductivity in LaH10±δ

Recently, tremendous research interest has been aroused in clathrate superhydrides. However, their microscopic properties, especially the superconducting (SC) gap and electron-phonon coupling (EPC) strength, are largely unexplored experimentally. Here, we investigate the time-resolved ultrafast spectroscopy of a superconductor LaH10±δ under an ultrahigh pressure of 165 GPa. By analyzing the ultrafast dynamics of the quasiparticles, we experimentally obtain the SC gap Δ(0) = 53 ± 5 meV, revealing a gap ratio 2Δ(0)/kBTc = 5.6 and a gap parameter ϑ = 1.95. Significantly, we experimentally estimate λ⟨Ω2⟩\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\lambda \\langle {\\Omega }^{2}\\rangle$$\\end{document} = (2.4 ± 0.1) × 104 (meV)2, which corresponds to an EPC strength λ = 2.58 ± 0.11. These results together provide direct experimental evidence that strong EPC is responsible for the near-room-temperature superconductivity in clathrate superhydrides. Our investigation significantly advances the experimental exploration of superhydrides, and contributes to the ultrafast dynamics investigations of quantum materials under high pressures.

The impact of national land supervision system on urban low-carbon transformation: evidence from China

The land system is a crucial factor influencing urban low-carbon sustainable development. However, previous research has paid little attention to the effects and mechanisms of the national land supervision system (NLSS) on urban low-carbon transformation (ULCT). This study uses China’s routine land inspection as a quasi-natural experiment and examines the impact of NLSS on ULCT using panel data from 283 Chinese cities between 2005 and 2016. The study finds that NLSS significantly promotes ULCT, with a series of robustness checks supporting this conclusion, showing a 1.95% improvement in carbon emission performance in cities under supervision. NLSS mainly facilitates ULCT by improving land use efficiency, upgrading the structural of the service sector, and promoting technological progress. Compared to eastern cities, southern cities, large cities, and non-resource-based cities, NLSS more effectively promotes low-carbon transformation in central and western, northern, small- and medium-sized, and resource-based cities. Additionally, in contrast to cities with high environmental awareness, high marketization levels, high financial development levels, and high fiscal pressure, NLSS more strongly promotes ULCT in cities with lower levels of these factors. Furthermore, NLSS exhibits a significant positive spatial spillover effect in promoting ULCT. In advancing ULCT, NLSS can be synergized with smart city pilot policies and innovative city pilot policies but has not shown synergies with low-carbon city pilot policies.

Prevalence and predictors of coronary heart disease among individuals with and without obesity in North Dakota

Introduction Coronary heart disease (CHD) is the most common cardiovascular disease in the United States and heart disease is the leading cause of death in North Dakota. Although obesity is a major risk factor for CHD, some studies have reported an inverse relationship between body mass index (BMI) and CHD outcomes. Understanding the epidemiology of CHD among individuals with and without obesity is essential to guide health planning. Therefore, the objectives of this study were to estimate the prevalence and identify predictors of CHD among North Dakota adults with and without obesity. Methods Behavioral Risk Factor Surveillance System data from 2017 to 2021 were provided by the North Dakota Department of Health and Human Services. Weighted prevalence estimates and 95% confidence intervals (CIs) were computed for CHD and potential risk factors among respondents with and without obesity (BMI ≥30 kg/m2). Multivariable logistic regression was used to identify significant predictors of CHD in both groups. Results A total of 17,092 respondents were included in the study. Respondents with obesity had a higher prevalence of CHD (4.7%, 95% CI: 4.2–5.4) than those without obesity (3.0%, 95% CI: 2.7–3.4). Predictors of CHD among both groups included age, sex, self-reported general health, high blood pressure, high cholesterol, chronic obstructive pulmonary disease, and diabetes. Having a personal doctor (Odds Ratio [OR] = 1.91, 95% CI: 1.13–3.23) and arthritis (OR = 1.72, 95% CI: 1.34–2.22) were significant predictors of CHD among respondents without obesity, but not among those without obesity. Conclusion While the prevalence of CHD was significantly higher among adults with obesity compared to those without obesity, the findings of the stratified analysis indicated that predictors of the condition tended to be similar for the two groups. This study provides useful information to guide health planning and control programs that aim to reduce the burden of CHD in North Dakota.

Pressure induced semiconductor-like to metal transition and linear magnetoresistance in Cr2S2.88 single crystal

Abstract The transition metal chalcogenide Cr2S3-x has unique properties, such as a lower antiferromagnetic transition temperature, semiconducting behavior, and thermoelectric properties. We focus on the effects of high pressure on the properties of electrical transport and structure in the single crystal Cr2S2.88. It is observed that the resistance drops abruptly by approximately two orders of magnitude and the temperature derivative of the resistance changes from negative to positive after 15.7 GPa. The Cr2S2.88 crystal has undergone transitions from a semiconductor-like phase to a metal I phase and then to another metal II phase. Simultaneously, a structural phase transition after 16.1 GPa is confirmed by synchrotron angle dispersive X-ray diffraction (AD-XRD). After the structural phase transition, the negative magnetoresistance becomes positive with increasing pressure and shows a linear relationship in the metal II phase. Electron-type carriers dominate in the semiconductor-like phase, but hole-type carriers dominate after the structural phase transition. Our work provides an example of the effective modulation of semiconductor-like properties by pressure, which is meaningful for the innovation and development of semiconductor technology.

The cause of an extreme sea surface warming in the midlatitude western North Pacific during 2012 summer

This study investigated an extreme sea surface warming in the midlatitude western North Pacific (MLWNP) during the summer of 2012. The 2012 extreme event was characterized by warm sea surface temperature anomaly (SSTA) extending from the East/Japan Sea to central North Pacific. The SSTA box–averaged over the MLWNP (130–180°E, 33–50°N) in 2012 ranked as the third warmest in recent four decades, which has caused intense marine heatwaves in this region. During the summer of 2012, a positive Indian Ocean Dipole event co-occurred with El Niño, favoring anomalous moisture transport between the two basins that caused enhanced convection in the South China and Philippine Seas and western–to–central subtropical Pacific. The enhanced convective activities triggered two meridional atmospheric Rossby wave trains to form strong atmospheric blocking high–pressure systems in the MLWNP. This reduced the total cloud cover and surface wind speed, enhancing insolation and reducing the release of latent heat flux. In addition, the weakened wind strengthened the stratification and shoaled the mixed layer. As a result, the increased net heat flux into the ocean accompanied by a shallower mixed layer contributed to the upper ocean warming in the MLWNP. Meanwhile, the North Pacific was dominated by a negative phase of Pacific Decadal Oscillation (PDO), significantly contributing to warm SSTAs in the MLWNP in 2012. Consequently, the 2012 extreme warming in the MLWNP was the results of the combination of atmospheric Rossby waves and PDO. Our study highlighted the roles of high–frequency atmospheric teleconnection and low–frequency PDO in extreme sea surface warming in the MLWNP.

Using magnesium hydride as the future dual-mode propellant for spacecraft: A simulation investigation

A dual-mode propulsion system stands as the important viable pathway for future multi-purpose deep space missions by the spacecraft, encompassing both nuclear thermal propulsion and nuclear electric propulsion. H2 and Mg emerge as potential mediums for nuclear thermal propulsion and nuclear electric propulsion, respectively, with the possibility of utilizing a single material, magnesium hydride (MgH2), to serve both purposes. However, how to release hydrogen completely and effectively in high hydrogen desorption pressure while retaining magnesium is the key problem. In this work, we proposed a novel MgH2 storage tank for zero gravity environments and investigated its hydrogen desorption process at high pressures of 4 ∼ 8 MPa using simulation, which is crucial for the hydrogen supply of nuclear thermal propulsion. We examined the effects of hydrogen desorption pressure, inlet temperature, and flow velocity of argon (Ar) on the desorption process. The simulation results indicated complete decomposition of MgH2 can be realized under 4 ∼ 8 MPa at 873 K. Moreover, the desorption pressure, inlet temperatures, and high flow velocities of Ar are suggested as 4 MPa, 773 ∼ 785 K, and 45 ∼ 100 m s−1 to achieve an average hydrogen desorption rate per unit thermal power of ≥ 20 mgH2 s−1. This work marks the first confirmation that MgH2 can decompose into H2 and Mg under high hydrogen desorption pressure at suitable thermal power, paving the way for its application as the hydrogen and Mg storage media in the dual-mode propulsion system of spacecraft.