The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ...The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ simulations with varied protocols to evaluate the effectiveness of different descriptors in predicting mechanical properties across both low-and high-pressure regimes.Our findings demonstrate that conventional structural and configurational descriptors fail to correlate with the mechanical response following pressure release,whereas the activation energy descriptor exhibits robust linearity with shear modulus after correcting for pressure effects.Notably,the soft mode parameter emerges as an ideal and computationally efficient alternative for capturing this mechanical behavior.These findings provide critical insights into the influence of pressure on glassy properties,integrating the distinct features of compressed glasses into a unified theoretical framework.展开更多
The Zenith Hydrostatic Delay(ZHD)is essential for high-precision Global Navigation Satellite System(GNSS)and Very Long Baseline Interferometry(VLBI)data processing.Accurate estimation of ZHD relies on in situ atmosphe...The Zenith Hydrostatic Delay(ZHD)is essential for high-precision Global Navigation Satellite System(GNSS)and Very Long Baseline Interferometry(VLBI)data processing.Accurate estimation of ZHD relies on in situ atmospheric pressure,which is primarily variable in the vertical direction.Current atmospheric pressure is either site-specific or has limited spatial coverage,necessitating vertical corrections for broader applicability.This study introduces a model that uses a Gaussian function for the vertical correction of atmospheric pressure when in situ meteorological observations are unavailable.Validation with the fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis(ERA5)reveals an average Bias and RMS for the new model of 0.31 h Pa and 2.96 h Pa,respectively.This corresponds to improvements of 37.5%and 80.3%in terms of RMS compared to two commonly used models(T0and Tvmodels)that require in situ meteorological observations,respectively.Additional validation with radiosonde data shows an average Bias and RMS of 1.85 h Pa and 4.87 h Pa,corresponding to the improvement of 42.8%and 71.1%in RMS compared with T0and Tv models,respectively.These accuracies are sufficient for calculating ZHD to an accuracy of 1 mm by performing atmospheric pressure vertical correction.The new model can correct atmospheric pressure from meteorological stations or numerical weather forecasts to different heights of the troposphere.展开更多
[Objectives]To investigate differences in BMI and renal function across constitution types and influencing factors of blood pressure.[Methods]92 college student volunteers aged 18-25 from January 2023 to December 2024...[Objectives]To investigate differences in BMI and renal function across constitution types and influencing factors of blood pressure.[Methods]92 college student volunteers aged 18-25 from January 2023 to December 2024 were selected.BMI,blood pressure,and renal function markers—blood urea nitrogen(BUN),creatinine(Cr),uric acid(UA),were compared across constitution types.Multiple stepwise regression analysis was applied to identify the influencing factors of blood pressure.[Results]Among 92 healthy participants aged 18-25,Shar-predominant constitution accounted for 50%,Khii-predominant for 25%,and Badgan-predominant for 20.65%.Significant differences existed in mean systolic and diastolic blood pressure across constitution types(systolic:F=4.56,P=0.001;diastolic:F=3.78,P=0.005).Shar-predominant group showed significantly higher systolic blood pressure than other types(P<0.05),while Khii-predominant group had higher diastolic pressure.Shar-predominant constitution demonstrated significantly greater height,weight,and BMI compared to other types(P<0.05).Males exhibited significantly higher height,weight,and BMI than females(P<0.05).Shar-predominant group showed significantly elevated urea,uric acid,and creatinine levels compared to other constitution types(P<0.05).Males had significantly higher mean urea,uric acid,and creatinine levels than females(P<0.05).Correlation analysis revealed stronger associations between BMI,renal function,and blood pressure in Shar-predominant group(r>0.50,P<0.05).Multiple regression analysis identified BMI as the primary influencing factor for blood pressure,followed by urea and uric acid.In Shar-predominant group,BMI exerted the strongest effect on blood pressure(β=0.60-0.65,P<0.001).[Conclusions]This study provides important evidence for health management in populations with different constitution types.展开更多
Liver-directed therapies such as resection,ablation,and embolization offer potentially curative options for patients with primary and metastatic liver tumors as part of multidisciplinary oncology care.However,these tr...Liver-directed therapies such as resection,ablation,and embolization offer potentially curative options for patients with primary and metastatic liver tumors as part of multidisciplinary oncology care.However,these treatments pose significant hepatic decompensation risks,particularly with underlying liver disease and chemotherapy-associated steatohepatitis.Accurate assessment of liver function and portal hypertension(PH)is critical for candidate selection.While Child-Pugh score and model for end-stage liver disease are commonly used,they have substantial limitations.Hepatic venous pressure gradient(HVPG)measurement remains the gold standard for assessing PH but is invasive and not widely available.Endoscopic ultrasound(EUS)guided portal pressure gradient(PPG)measurement has emerged as a promising minimally invasive alternative.EUSPPG demonstrates excellent technical success rates,safety profile,and correlation with HVPG in early studies.By providing direct portal pressure measurement,EUS-PPG offers several advantages over existing methods for prognostication and risk stratification prior to liver-directed therapies,particularly in detecting presinusoidal hypertension.Furthermore,it has potential applications in assessing response to neoadjuvant treatments and guiding adjuvant therapies.However,research is needed to validate its predictive performance and cost-effectiveness in larger prospective cohorts and to establish its accuracy compared to non-invasive assessment of liver function.展开更多
Long-term exposure to fine particulate matters(PM_(2.5))has been associated with respiratory and cardiovascular diseases and the burden are potentially higher in China experiencing heavy air pollution.In this study,we...Long-term exposure to fine particulate matters(PM_(2.5))has been associated with respiratory and cardiovascular diseases and the burden are potentially higher in China experiencing heavy air pollution.In this study,we established the exposure-response association between long-term exposures to PM_(2.5)and lung function and blood pressure in Chinesemiddle-aged and older adults using linearmixed-effects and generalized additive mixedmodels based on 3 waves longitudinal health outcomes data by enrolling 19,988 participants from 121 cities across themainland of China.We also assessed the effect of Clean Air Policy(CAP)based on a quasi-experimental difference-in-differences(DID)design.A 10μg/m^(3)increase in PM_(2.5)concentration was associated with a 7.18(95%confidence interval[CI]:-8.35,-6.02)L/min decrease in PEF(peak expiratory flow)and a 0.72(95%[CI]:0.53,0.90)and a 0.30(95%[CI]:0.18,0.42)mmHg increase in systolic and diastolic blood pressure,respectively.The associations were more pronounced in males and rural areas for PEF,but similar across subgroups for blood pressure.DID results suggested that the effect of CAP on health outcomes were sensitive tomagnitudes of reduction in PM_(2.5).A 5μg/m^(3)reduction in PM_(2.5)or more generally led to 18.70(95%[CI]:0.79,36.61)higher PEF and-2.05(95%[CI]:-3.87,-0.23)lower diastolic blood pressure,respectively,compared to no reduction or increase in exposure.However,the effects were significant only in rural areas.Our analysis support CAP aiming to benefit public health and provides insights to inform future control policy for efficiently decreasing air pollution exposure burden.展开更多
Objective:To explore the effect of continuous positive airway pressure(CPAP)therapy on daytime sleepiness and cognitive function in patients with moderate to severe obstructive sleep apnea-hypopnea syndrome(OSAHS).Met...Objective:To explore the effect of continuous positive airway pressure(CPAP)therapy on daytime sleepiness and cognitive function in patients with moderate to severe obstructive sleep apnea-hypopnea syndrome(OSAHS).Methods:From January to December 2024,60 patients with moderate to severe OSAHS were enrolled and randomly divided into an observation group and a control group,with 30 patients in each group.The observation group received CPAP combined with routine intervention,while the control group only received routine intervention,with a course of 3 months for both groups.Results:After 3 months of intervention,the observation group showed significantly better improvements in the frequency and duration of daytime sleepiness as well as all dimensions of cognitive function compared with the control group,and the differences were statistically significant(P<0.05).Conclusion:CPAP therapy can effectively relieve daytime sleepiness in patients with moderate to severe OSAHS,and significantly improve memory,attention and logical thinking ability.The comprehensive intervention effect is superior to simple routine management.展开更多
The exact thermoelastic analysis of a functionally graded piezoelectrical (FGP) rotating cylinder is investigated analytically. The cylinder is subjected to a com- bination of electrical, thermal, and mechanical loa...The exact thermoelastic analysis of a functionally graded piezoelectrical (FGP) rotating cylinder is investigated analytically. The cylinder is subjected to a com- bination of electrical, thermal, and mechanical loads simultaneously. The structure is a simplified model of a rotational sensor or actuator. The basic governing differential equation of the system is obtained by using the energy method. A novel term, named as the additional energy, is introduced to exact the evaluation of the energy functional. The solution to the governing differential equation is presented for two types of boundary conditions including free rotating and rotating cylinders exposed to the inner pressure. The effect of the angular velocity is investigated on the radial distribution of various components. The mentioned structure can be considered as a sensor for measuring the angular velocity of the cylinder subjected to the pressure and temperature. The obtained results indicate that the electrical potential is proportional to the angular velocity.展开更多
AIM To measure single baseline deep posterior compartment pressure in tibial fracture complicated by acute compartment syndrome(ACS) and to correlate it with functional outcome.METHODS Thirty-two tibial fractures with...AIM To measure single baseline deep posterior compartment pressure in tibial fracture complicated by acute compartment syndrome(ACS) and to correlate it with functional outcome.METHODS Thirty-two tibial fractures with ACS were evaluated clinically and the deep posterior compartment pressure was measured. Urgent fasciotomy was needed in 30 patients. Definite surgical fixation was performed either primarily or once fasciotomy wound was healthy. The patients were followed up at 3 mo, 6 mo and one year. At one year, the functional outcome [lower extremity functional scale(LEFS)] and complications were assessed.RESULTS Three limbs were amputated. In remaining 29 patients, the average times for clinical and radiological union were 25.2 ± 10.9 wk(10 to 54 wk) and 23.8 ± 9.2 wk(12 to 52 wk) respectively. Nine patients had delayed union and 2 had nonunion who needed bone grafting to augment healing. Most common complaint at follow up was ankle stiffness(76%) that caused difficulty in walking,running and squatting. Of 21 patients who had paralysis at diagnosis, 13(62%) did not recover and additional five patients developed paralysis at follow-up. On LEFS evaluation, there were 14 patients(48.3%) with severe disability, 10 patients(34.5%) with moderate disability and 5 patients(17.2%) with minimal disability. The mean pressures in patients with minimal disability, moderate disability and severe disability were 37.8, 48.4 and 58.79 mmH g respectively(P < 0.001).CONCLUSION ACS in tibial fractures causes severe functional disability in majority of patients. These patients are prone for delayed union and nonunion; however, long term disability is mainly because of severe soft tissue contracture. Intracompartmental pressure(ICP) correlates with functional disability; patients with relatively high ICP are prone for poor functional outcome.展开更多
This study presents an analytical solution of thermal and mechanical displacements, strains, and stresses for a thick-walled rotating spherical pressure vessel made of functionally graded materials (FGMs). The pressur...This study presents an analytical solution of thermal and mechanical displacements, strains, and stresses for a thick-walled rotating spherical pressure vessel made of functionally graded materials (FGMs). The pressure vessel is subject to axisymmetric mechanical and thermal loadings within a uniform magnetic field. The material properties of the FGM are considered as the power-law distribution along the thickness. Navier’s equation, which is a second-order ordinary differential equation, is derived from the mechanical equilibrium equation with the consideration of the thermal stresses and the Lorentz force resulting from the magnetic field. The distributions of the displacement, strains, and stresses are determined by the exact solution to Navier’s equation. Numerical results clarify the influence of the thermal loading, magnetic field, non-homogeneity constant, internal pressure, and angular velocity on the magneto-thermo-elastic response of the functionally graded spherical vessel. It is observed that these parameters have remarkable effects on the distributions of radial displacement, radial and circumferential strains, and radial and circumferential stresses.展开更多
Objective: To investigate the effects of low central venous pressure (LVCP) on blood loss and evaluate its influence on renal function in patients undergoing hepatectomy. Methods: Forty-six patients, ASA classific...Objective: To investigate the effects of low central venous pressure (LVCP) on blood loss and evaluate its influence on renal function in patients undergoing hepatectomy. Methods: Forty-six patients, ASA classification Ⅰ-Ⅲ, undergoing liver resection were randomized into LCVP group (n = 23) and control group (n = 23). In LCVP group, CVP was maintained at 2-4 mmHg and MBP above 60 mmHg during hepatectomy, while in control group hepatectomy was performed routinely without lowering CVP. Volume of blood loss during hepatectomy, volume of blood transfusion, and changes of renal functions were compared between the two groups. Results: There were no significant differences in demographics, ASA score, type of hepatectomy, duration of inflow occlusion, operation time, weight of resected liver tissues, and renal functions between the two groups. LCVP group had a significantly lower volume of total intraoperative blood loss (P 〈 0.01) and RBC transfusion (P 〈 0.05). Conclusion: Lowering the CVP to less than 5 mmHg is a simple and effective technique to reduce blood loss and blood infusion during liver resection, and has no detrimental effects on renal functions.展开更多
AIM: To determine the influence of intra-abdominal pressure(IAP) on respiratory function after surgical repair of ventral hernia and to compare two different methods of IAP measurement during the perioperative period....AIM: To determine the influence of intra-abdominal pressure(IAP) on respiratory function after surgical repair of ventral hernia and to compare two different methods of IAP measurement during the perioperative period. METHODS: Thirty adult patients after elective repair of ventral hernia were enrolled into this prospective study.IAP monitoring was performed via both a balloontipped nasogastric probe [intragastric pressure(IGP), Ci MON, Pulsion Medical Systems, Munich, Germany] and a urinary catheter [intrabladder pressure(IBP), Uno Meter Abdo-Pressure Kit, Uno Medical, Denmark] on five consecutive stages:(1) after tracheal intubation(AI);(2) after ventral hernia repair;(3) at the end of surgery;(4) during spontaneous breathing trial through the endotracheal tube; and(5) at 1 h after tracheal extubation. The patients were in the complete supine position during all study stages.RESULTS: The IAP(measured via both techniques) increased on average by 12% during surgery compared to AI(P < 0.02) and by 43% during spontaneous breathing through the endotracheal tube(P < 0.01). In parallel, the gradient between РаСО2 and Et CO2 [Р(а-et)CO2] rose significantly, reaching a maximum during the spontaneous breathing trial. The PаO2/Fi O2 decreased by 30% one hour after tracheal extubation(P = 0.02). The dynamic compliance of respiratory system reduced intraoperatively by 15%-20%(P < 0.025). At all stages, we observed a significant correlation between IGP and IBP(r = 0.65-0.81, P < 0.01) with a mean bias varying from-0.19 mm Hg(2SD 7.25 mm Hg) to-1.06 mm Hg(2SD 8.04 mm Hg) depending on the study stage. Taking all paired measurements together(n = 133), the median IGP was 8.0(5.5-11.0) mm Hg and the median IBP was 8.8(5.8-13.1) mm Hg. The overall r2 value( n = 30) was 0.76(P < 0.0001). Bland and Altman analysis showed an overall bias for the mean values per patient of 0.6 mm Hg(2SD 4.2 mm Hg) with percentage error of 45.6%. Looking at changes in IAP between the different study stages, we found an excellent concordance coefficient of 94.9% comparing IBP and IGP( n = 117).CONCLUSION: During ventral hernia repair, the IAP rise is accompanied by changes in Р(а-et)CO2 and PаO2/Fi O2-ratio. Estimation of IAP via IGP or IBP demonstrated excellent concordance.展开更多
The flow behavior in porous media with threshold pressure gradient(TPG) is more complex than Darcy flow and the equations of motion, and outer boundary and inner boundary with TPG are also different from Darcy flow fo...The flow behavior in porous media with threshold pressure gradient(TPG) is more complex than Darcy flow and the equations of motion, and outer boundary and inner boundary with TPG are also different from Darcy flow for unsteady flow of a producing well in a reservoir. An analytic method to solve this kind of problem is in a need of reestablishment. The classical method of Green's function and Newman product principle in a new way are used to solve the unsteady state flow problems of various shapes of well and reservoir while considering the TPG. Four Green's functions of point, line, band and circle while considering the TPG are achieved. Then, two well models of vertical well and horizontal well are built and simultaneously the function to calculate the moving boundary of each well model is provided. The results show that when considering TPG the pressure field is much different, which has a sudden pressure change, with a moving boundary in it. And the moving boundary of each well model increases with time but slows down rapidly, especially when the TGP is large.展开更多
Gasoline direct injection(GDI)is a pivotal technique for a highly efficient engine.However,how to maintain a stable rail pressure which offers good fuel economy and low emissions,is still a challengeable work.In this ...Gasoline direct injection(GDI)is a pivotal technique for a highly efficient engine.However,how to maintain a stable rail pressure which offers good fuel economy and low emissions,is still a challengeable work.In this paper,a rail pressure controller is designed basing on predictive functional control(PFC),a model predictive control(MPC)method,to surmount the nonlinearity and disc on tinuity brought by the common rail pressure system(CRPS).A control-oriented piecewise linear model is prese nted to simplify the CRPS.The simulation results on a benchmark show that rail pressure tracks the setpoint accurately even with some perturbations.Profiting from the conciseness of PFC algorithm,the controller can compute the online solution in a short time,which makes it possible to realize the strategy on a fast response system.展开更多
Objective: The aim of this study was to assess the relationship of blood pressure variability (BPV) and heart rate variability (HRV) to investigate the effect of baroreflex function on blood pressure variability. Meth...Objective: The aim of this study was to assess the relationship of blood pressure variability (BPV) and heart rate variability (HRV) to investigate the effect of baroreflex function on blood pressure variability. Methods: This study consisted of 111 subjects, including 32 normotensives and 79 hypertensives. All the subjects were given two concurrent tests: 24-hour Holter ECG and ambulatory blood pressure monitoring. According to standard deviation of normal-to-normal sinus RR intervals (SDNN) derived from the Holter ECG, the hypertensives were divided into two groups: an HRV normal group with SDNN > 100 ms and an HRV abnormal group with展开更多
HPP (high pressure processing) is one of the novel technologies to produce microbiologically safe food. HPP is a non-thermal food processing method, wherein the food is subjected to a very high pressure ranging betw...HPP (high pressure processing) is one of the novel technologies to produce microbiologically safe food. HPP is a non-thermal food processing method, wherein the food is subjected to a very high pressure ranging between 100-800 MPa in order to prevent undesirable chemical and microbiological reactions, and hence, prolong the shelf-life. HPP is also called as "high hydrostatic processing, ultra-high pressure processing or isostatic processing". In dairy products, HHP has the potential to modify the functional properties of proteins, polysaccharides and alter biochemical reactions without significantly affecting the nutritional and sensory properties. HPP treatment induces significant changes in milk components particularly in proteins (whey proteins and caseins), as well as on their applicability in innovative dairy productions. HPP influences technological properties of various milk products such as firmness, water-holding capacity of the gel and network structure, cheese yield, rennet coagulation time and ripening.展开更多
Laves-phase are among the most abundant groups of alloys with chemical formula AB_(2),known for their hightemperature strength and potential application in hydrogen storage.The Laves-phase generally acts as a strength...Laves-phase are among the most abundant groups of alloys with chemical formula AB_(2),known for their hightemperature strength and potential application in hydrogen storage.The Laves-phase generally acts as a strengthening agent,which enhances the strength and durability of alloys at extreme conditions.Consequently,the properties of Lavesphase alloys at extreme conditions attract wide attention.In this study,we investigated the high-pressure phase diagram of Laves-phase alloy HfZn_(2),and discovered a phase transition from C15(space group Fd3m)phase to C14(space group P63/mmc)phase at a pressure above 20 GPa.Based on ab initio simulations,the mechanical,chemical bonding and superconducting properties of high-pressure phase HfZn_(2)were predicted.The ratio of bulk modulus to shear modulus(B/G),a key indicator of mechanical properties in alloys,increases from 1.86 to 4.09 within the pressure range of 50-250 GPa,indicating excellent ductility of the C14 phase of HfZn_(2)under high pressure.Additionally,Zn gains approximately 0.43 electron from Hf at 10 GPa,and the superconducting critical temperature of HfZn_(2)is estimated to be around 0.55 K at 50 GPa.Given that both C14 and C15 phases are common structures in Laves-phase alloys,elucidating the high-pressure behaviors of C14 and C15 phases of HfZn_(2)will enhance the fundamental understanding of properties and potential applications at extreme conditions of Laves-phase alloys.展开更多
Density functional theory(DFT)studies were performed on the lattice parameters,electronic band structure,and optical constants under pressure up to 20 GPa in order to obtain insight into the electronic and optical pro...Density functional theory(DFT)studies were performed on the lattice parameters,electronic band structure,and optical constants under pressure up to 20 GPa in order to obtain insight into the electronic and optical properties of LiZnAs.The calculated results show LiZnAs is a semiconductor with a direct gap of 0.86 eV,which is smaller than the experimental value 1.1 eV.It also indicates that the structural parameters such as lattice parameters and cell volume show inverse relation to the pressure and shows smooth decreasing behavior from 0 to 20 GPa.Meanwhile,the pressure dependence of the electronic band structure,density of states and partial density of states of LiZnAs up to 20 GPa were presented.And we found that the band gap increased with the pressure.Moreover,the evolution of the dielectric function,absorption coefficient a(w),reflectivity R(w),the refractive index n(w),and the extinction coefficient k(w)of LiZnAs under pressure were presented.According to our work,we found that the optical properties of LiZnAs undergo a blue shift with increasing pressure.These results suggest technological applications of such materials in extreme environments.展开更多
BACKGROUND Patients with head and neck cancer often develop depressive symptoms during radiochemotherapy due to changes in saliva secretion,radiation-induced oral mucositis,and dysphagia.These symptoms significantly a...BACKGROUND Patients with head and neck cancer often develop depressive symptoms during radiochemotherapy due to changes in saliva secretion,radiation-induced oral mucositis,and dysphagia.These symptoms significantly affect quality of life.Although existing nursing interventions provide some relief,they have limitations in improving swallowing function and developing coping strategies.AIM To evaluate the effectiveness of tongue pressure resistance feedback training combined with empowerment education in improving depressive symptoms and swallowing function in patients with head and neck cancer undergoing radiochemotherapy.METHODS This study included 110 patients with head and neck cancer who exhibited depressive symptoms and underwent radiochemotherapy at the Affiliated Hospital of Jiangnan University between January 2021 and December 2023.Patients were randomly assigned to either a reference group or an experimental group,each comprising 55 patients.The reference group received routine care,whereas the experimental group received tongue pressure resistance feedback training and empowerment education.After 6 weeks of continuous intervention,comparisons were made between the two groups regarding depressive symptom scores,swallowing function,coping strategies,and quality of life,both pre-and post-intervention.RESULTS Following the intervention,both groups demonstrated decreased scores for depressive symptoms and swallowing function,with the experimental group showing a significantly greater reduction than the reference group(P<0.05).The experimental group also demonstrated higher confrontation scores and lower avoidance and submission scores for coping strategies than the reference group(P<0.05).Quality of life scores improved in both groups after the intervention,with the experimental group showing markedly higher scores than the reference group(P<0.05).CONCLUSION The combination of tongue pressure resistance feedback training and empowerment education is effective in alleviating depressive symptoms,enhancing swallowing function,optimizing coping strategies,and significantly improving the quality of life of patients with head and neck cancer undergoing radiochemotherapy.This approach shows promise for clinical applications and promotion.展开更多
By using the statistical mechanics, the pressure tensor for the multi component fluid mixture is derived. With the help of the classical density functional theory, profiles of the pressure components are calculated, a...By using the statistical mechanics, the pressure tensor for the multi component fluid mixture is derived. With the help of the classical density functional theory, profiles of the pressure components are calculated, and the influence of the total volume fraction, ratio of volume fraction, and size asymmetry on the pressure are studied. In addition, our results show that for the mixture confined in the hard cavity, the pressure shows a discontinuity near the cavity wall. However, in the soft cavity condition, the discontinuity disappears.展开更多
We study the effect of pressure on electronic and thermoelectric properties of Mg_2Si using the density functional theory and Boltzmann transport equations. The variation of lattice constant, band gap, bulk modulus wi...We study the effect of pressure on electronic and thermoelectric properties of Mg_2Si using the density functional theory and Boltzmann transport equations. The variation of lattice constant, band gap, bulk modulus with pressure is also analyzed. Further, the thermoelectric properties(Seebeck coefficient, electrical conductivity, electronic thermal conductivity) have been studied as a function of temperature and pressure up to 1200 K. The results show that Mg_2Si is an n-type semiconductor with a band gap of 0.21 eV. The negative value of the Seebeck coefficient at all pressures indicates that the conduction is due to electrons. With the increase in pressure, the Seebeck coefficient decreases and electrical conductivity increases. It is also seen that, there is practically no effect of pressure on the electronic contribution of thermal conductivity.The paper describes the calculation of the lattice thermal conductivity and figure of merit of Mg_2Si at zero pressure. The maximum value of figure of merit is attained 1.83 × 10^(-3) at 1000 K. The obtained results are in good agreement with the available experimental and theoretical results.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.T2325004 and 52161160330)the National Natural Science Foundation of China (Grants No.12504233)+2 种基金Advanced MaterialsNational Science and Technology Major Project (Grant No.2024ZD0606900)the Talent Hub for “AI+New Materials” Basic Researchthe Key Research and Development Program of Ningbo (Grant No.2025Z088)。
文摘The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ simulations with varied protocols to evaluate the effectiveness of different descriptors in predicting mechanical properties across both low-and high-pressure regimes.Our findings demonstrate that conventional structural and configurational descriptors fail to correlate with the mechanical response following pressure release,whereas the activation energy descriptor exhibits robust linearity with shear modulus after correcting for pressure effects.Notably,the soft mode parameter emerges as an ideal and computationally efficient alternative for capturing this mechanical behavior.These findings provide critical insights into the influence of pressure on glassy properties,integrating the distinct features of compressed glasses into a unified theoretical framework.
基金supported by the National Natural Science Foundation of China(42304018)the National Natural Science Foundation of China(42330105,42064002,42074035)+3 种基金the Guangxi Natural Science Foundation of China(Guike AD23026177,2020GXNSFBA297145)the Foundation of Guilin University of Technology(GUTQDJJ6616032)Guangxi Key Laboratory of Spatial Information and Geomatics(21238-21-05)the Innovation Project of Guangxi Graduate Education(YCSW2023341)。
文摘The Zenith Hydrostatic Delay(ZHD)is essential for high-precision Global Navigation Satellite System(GNSS)and Very Long Baseline Interferometry(VLBI)data processing.Accurate estimation of ZHD relies on in situ atmospheric pressure,which is primarily variable in the vertical direction.Current atmospheric pressure is either site-specific or has limited spatial coverage,necessitating vertical corrections for broader applicability.This study introduces a model that uses a Gaussian function for the vertical correction of atmospheric pressure when in situ meteorological observations are unavailable.Validation with the fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis(ERA5)reveals an average Bias and RMS for the new model of 0.31 h Pa and 2.96 h Pa,respectively.This corresponds to improvements of 37.5%and 80.3%in terms of RMS compared to two commonly used models(T0and Tvmodels)that require in situ meteorological observations,respectively.Additional validation with radiosonde data shows an average Bias and RMS of 1.85 h Pa and 4.87 h Pa,corresponding to the improvement of 42.8%and 71.1%in RMS compared with T0and Tv models,respectively.These accuracies are sufficient for calculating ZHD to an accuracy of 1 mm by performing atmospheric pressure vertical correction.The new model can correct atmospheric pressure from meteorological stations or numerical weather forecasts to different heights of the troposphere.
基金Supported by Project of Science and Technology Department of Inner Mongolia Autonomous Region(2021GG0117).
文摘[Objectives]To investigate differences in BMI and renal function across constitution types and influencing factors of blood pressure.[Methods]92 college student volunteers aged 18-25 from January 2023 to December 2024 were selected.BMI,blood pressure,and renal function markers—blood urea nitrogen(BUN),creatinine(Cr),uric acid(UA),were compared across constitution types.Multiple stepwise regression analysis was applied to identify the influencing factors of blood pressure.[Results]Among 92 healthy participants aged 18-25,Shar-predominant constitution accounted for 50%,Khii-predominant for 25%,and Badgan-predominant for 20.65%.Significant differences existed in mean systolic and diastolic blood pressure across constitution types(systolic:F=4.56,P=0.001;diastolic:F=3.78,P=0.005).Shar-predominant group showed significantly higher systolic blood pressure than other types(P<0.05),while Khii-predominant group had higher diastolic pressure.Shar-predominant constitution demonstrated significantly greater height,weight,and BMI compared to other types(P<0.05).Males exhibited significantly higher height,weight,and BMI than females(P<0.05).Shar-predominant group showed significantly elevated urea,uric acid,and creatinine levels compared to other constitution types(P<0.05).Males had significantly higher mean urea,uric acid,and creatinine levels than females(P<0.05).Correlation analysis revealed stronger associations between BMI,renal function,and blood pressure in Shar-predominant group(r>0.50,P<0.05).Multiple regression analysis identified BMI as the primary influencing factor for blood pressure,followed by urea and uric acid.In Shar-predominant group,BMI exerted the strongest effect on blood pressure(β=0.60-0.65,P<0.001).[Conclusions]This study provides important evidence for health management in populations with different constitution types.
文摘Liver-directed therapies such as resection,ablation,and embolization offer potentially curative options for patients with primary and metastatic liver tumors as part of multidisciplinary oncology care.However,these treatments pose significant hepatic decompensation risks,particularly with underlying liver disease and chemotherapy-associated steatohepatitis.Accurate assessment of liver function and portal hypertension(PH)is critical for candidate selection.While Child-Pugh score and model for end-stage liver disease are commonly used,they have substantial limitations.Hepatic venous pressure gradient(HVPG)measurement remains the gold standard for assessing PH but is invasive and not widely available.Endoscopic ultrasound(EUS)guided portal pressure gradient(PPG)measurement has emerged as a promising minimally invasive alternative.EUSPPG demonstrates excellent technical success rates,safety profile,and correlation with HVPG in early studies.By providing direct portal pressure measurement,EUS-PPG offers several advantages over existing methods for prognostication and risk stratification prior to liver-directed therapies,particularly in detecting presinusoidal hypertension.Furthermore,it has potential applications in assessing response to neoadjuvant treatments and guiding adjuvant therapies.However,research is needed to validate its predictive performance and cost-effectiveness in larger prospective cohorts and to establish its accuracy compared to non-invasive assessment of liver function.
基金supported by the National Institute of Environmental Health Sciences(NIEHS)of United States(No.R00ES027511)the National Natural Science Foundation of China(No.42201303).
文摘Long-term exposure to fine particulate matters(PM_(2.5))has been associated with respiratory and cardiovascular diseases and the burden are potentially higher in China experiencing heavy air pollution.In this study,we established the exposure-response association between long-term exposures to PM_(2.5)and lung function and blood pressure in Chinesemiddle-aged and older adults using linearmixed-effects and generalized additive mixedmodels based on 3 waves longitudinal health outcomes data by enrolling 19,988 participants from 121 cities across themainland of China.We also assessed the effect of Clean Air Policy(CAP)based on a quasi-experimental difference-in-differences(DID)design.A 10μg/m^(3)increase in PM_(2.5)concentration was associated with a 7.18(95%confidence interval[CI]:-8.35,-6.02)L/min decrease in PEF(peak expiratory flow)and a 0.72(95%[CI]:0.53,0.90)and a 0.30(95%[CI]:0.18,0.42)mmHg increase in systolic and diastolic blood pressure,respectively.The associations were more pronounced in males and rural areas for PEF,but similar across subgroups for blood pressure.DID results suggested that the effect of CAP on health outcomes were sensitive tomagnitudes of reduction in PM_(2.5).A 5μg/m^(3)reduction in PM_(2.5)or more generally led to 18.70(95%[CI]:0.79,36.61)higher PEF and-2.05(95%[CI]:-3.87,-0.23)lower diastolic blood pressure,respectively,compared to no reduction or increase in exposure.However,the effects were significant only in rural areas.Our analysis support CAP aiming to benefit public health and provides insights to inform future control policy for efficiently decreasing air pollution exposure burden.
文摘Objective:To explore the effect of continuous positive airway pressure(CPAP)therapy on daytime sleepiness and cognitive function in patients with moderate to severe obstructive sleep apnea-hypopnea syndrome(OSAHS).Methods:From January to December 2024,60 patients with moderate to severe OSAHS were enrolled and randomly divided into an observation group and a control group,with 30 patients in each group.The observation group received CPAP combined with routine intervention,while the control group only received routine intervention,with a course of 3 months for both groups.Results:After 3 months of intervention,the observation group showed significantly better improvements in the frequency and duration of daytime sleepiness as well as all dimensions of cognitive function compared with the control group,and the differences were statistically significant(P<0.05).Conclusion:CPAP therapy can effectively relieve daytime sleepiness in patients with moderate to severe OSAHS,and significantly improve memory,attention and logical thinking ability.The comprehensive intervention effect is superior to simple routine management.
文摘The exact thermoelastic analysis of a functionally graded piezoelectrical (FGP) rotating cylinder is investigated analytically. The cylinder is subjected to a com- bination of electrical, thermal, and mechanical loads simultaneously. The structure is a simplified model of a rotational sensor or actuator. The basic governing differential equation of the system is obtained by using the energy method. A novel term, named as the additional energy, is introduced to exact the evaluation of the energy functional. The solution to the governing differential equation is presented for two types of boundary conditions including free rotating and rotating cylinders exposed to the inner pressure. The effect of the angular velocity is investigated on the radial distribution of various components. The mentioned structure can be considered as a sensor for measuring the angular velocity of the cylinder subjected to the pressure and temperature. The obtained results indicate that the electrical potential is proportional to the angular velocity.
文摘AIM To measure single baseline deep posterior compartment pressure in tibial fracture complicated by acute compartment syndrome(ACS) and to correlate it with functional outcome.METHODS Thirty-two tibial fractures with ACS were evaluated clinically and the deep posterior compartment pressure was measured. Urgent fasciotomy was needed in 30 patients. Definite surgical fixation was performed either primarily or once fasciotomy wound was healthy. The patients were followed up at 3 mo, 6 mo and one year. At one year, the functional outcome [lower extremity functional scale(LEFS)] and complications were assessed.RESULTS Three limbs were amputated. In remaining 29 patients, the average times for clinical and radiological union were 25.2 ± 10.9 wk(10 to 54 wk) and 23.8 ± 9.2 wk(12 to 52 wk) respectively. Nine patients had delayed union and 2 had nonunion who needed bone grafting to augment healing. Most common complaint at follow up was ankle stiffness(76%) that caused difficulty in walking,running and squatting. Of 21 patients who had paralysis at diagnosis, 13(62%) did not recover and additional five patients developed paralysis at follow-up. On LEFS evaluation, there were 14 patients(48.3%) with severe disability, 10 patients(34.5%) with moderate disability and 5 patients(17.2%) with minimal disability. The mean pressures in patients with minimal disability, moderate disability and severe disability were 37.8, 48.4 and 58.79 mmH g respectively(P < 0.001).CONCLUSION ACS in tibial fractures causes severe functional disability in majority of patients. These patients are prone for delayed union and nonunion; however, long term disability is mainly because of severe soft tissue contracture. Intracompartmental pressure(ICP) correlates with functional disability; patients with relatively high ICP are prone for poor functional outcome.
文摘This study presents an analytical solution of thermal and mechanical displacements, strains, and stresses for a thick-walled rotating spherical pressure vessel made of functionally graded materials (FGMs). The pressure vessel is subject to axisymmetric mechanical and thermal loadings within a uniform magnetic field. The material properties of the FGM are considered as the power-law distribution along the thickness. Navier’s equation, which is a second-order ordinary differential equation, is derived from the mechanical equilibrium equation with the consideration of the thermal stresses and the Lorentz force resulting from the magnetic field. The distributions of the displacement, strains, and stresses are determined by the exact solution to Navier’s equation. Numerical results clarify the influence of the thermal loading, magnetic field, non-homogeneity constant, internal pressure, and angular velocity on the magneto-thermo-elastic response of the functionally graded spherical vessel. It is observed that these parameters have remarkable effects on the distributions of radial displacement, radial and circumferential strains, and radial and circumferential stresses.
文摘Objective: To investigate the effects of low central venous pressure (LVCP) on blood loss and evaluate its influence on renal function in patients undergoing hepatectomy. Methods: Forty-six patients, ASA classification Ⅰ-Ⅲ, undergoing liver resection were randomized into LCVP group (n = 23) and control group (n = 23). In LCVP group, CVP was maintained at 2-4 mmHg and MBP above 60 mmHg during hepatectomy, while in control group hepatectomy was performed routinely without lowering CVP. Volume of blood loss during hepatectomy, volume of blood transfusion, and changes of renal functions were compared between the two groups. Results: There were no significant differences in demographics, ASA score, type of hepatectomy, duration of inflow occlusion, operation time, weight of resected liver tissues, and renal functions between the two groups. LCVP group had a significantly lower volume of total intraoperative blood loss (P 〈 0.01) and RBC transfusion (P 〈 0.05). Conclusion: Lowering the CVP to less than 5 mmHg is a simple and effective technique to reduce blood loss and blood infusion during liver resection, and has no detrimental effects on renal functions.
文摘AIM: To determine the influence of intra-abdominal pressure(IAP) on respiratory function after surgical repair of ventral hernia and to compare two different methods of IAP measurement during the perioperative period. METHODS: Thirty adult patients after elective repair of ventral hernia were enrolled into this prospective study.IAP monitoring was performed via both a balloontipped nasogastric probe [intragastric pressure(IGP), Ci MON, Pulsion Medical Systems, Munich, Germany] and a urinary catheter [intrabladder pressure(IBP), Uno Meter Abdo-Pressure Kit, Uno Medical, Denmark] on five consecutive stages:(1) after tracheal intubation(AI);(2) after ventral hernia repair;(3) at the end of surgery;(4) during spontaneous breathing trial through the endotracheal tube; and(5) at 1 h after tracheal extubation. The patients were in the complete supine position during all study stages.RESULTS: The IAP(measured via both techniques) increased on average by 12% during surgery compared to AI(P < 0.02) and by 43% during spontaneous breathing through the endotracheal tube(P < 0.01). In parallel, the gradient between РаСО2 and Et CO2 [Р(а-et)CO2] rose significantly, reaching a maximum during the spontaneous breathing trial. The PаO2/Fi O2 decreased by 30% one hour after tracheal extubation(P = 0.02). The dynamic compliance of respiratory system reduced intraoperatively by 15%-20%(P < 0.025). At all stages, we observed a significant correlation between IGP and IBP(r = 0.65-0.81, P < 0.01) with a mean bias varying from-0.19 mm Hg(2SD 7.25 mm Hg) to-1.06 mm Hg(2SD 8.04 mm Hg) depending on the study stage. Taking all paired measurements together(n = 133), the median IGP was 8.0(5.5-11.0) mm Hg and the median IBP was 8.8(5.8-13.1) mm Hg. The overall r2 value( n = 30) was 0.76(P < 0.0001). Bland and Altman analysis showed an overall bias for the mean values per patient of 0.6 mm Hg(2SD 4.2 mm Hg) with percentage error of 45.6%. Looking at changes in IAP between the different study stages, we found an excellent concordance coefficient of 94.9% comparing IBP and IGP( n = 117).CONCLUSION: During ventral hernia repair, the IAP rise is accompanied by changes in Р(а-et)CO2 and PаO2/Fi O2-ratio. Estimation of IAP via IGP or IBP demonstrated excellent concordance.
基金Project(51304220) supported by the National Natural Science Foundation of ChinaProject(3144033) supported by the Beijing Natural Science Foundation,ChinaProject(20130007120014) supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘The flow behavior in porous media with threshold pressure gradient(TPG) is more complex than Darcy flow and the equations of motion, and outer boundary and inner boundary with TPG are also different from Darcy flow for unsteady flow of a producing well in a reservoir. An analytic method to solve this kind of problem is in a need of reestablishment. The classical method of Green's function and Newman product principle in a new way are used to solve the unsteady state flow problems of various shapes of well and reservoir while considering the TPG. Four Green's functions of point, line, band and circle while considering the TPG are achieved. Then, two well models of vertical well and horizontal well are built and simultaneously the function to calculate the moving boundary of each well model is provided. The results show that when considering TPG the pressure field is much different, which has a sudden pressure change, with a moving boundary in it. And the moving boundary of each well model increases with time but slows down rapidly, especially when the TGP is large.
基金the National Key R&D Program of China(No.2018YFB1701102)the Natural Science Foundation of Zhejiang,China(No.LR17F030002).
文摘Gasoline direct injection(GDI)is a pivotal technique for a highly efficient engine.However,how to maintain a stable rail pressure which offers good fuel economy and low emissions,is still a challengeable work.In this paper,a rail pressure controller is designed basing on predictive functional control(PFC),a model predictive control(MPC)method,to surmount the nonlinearity and disc on tinuity brought by the common rail pressure system(CRPS).A control-oriented piecewise linear model is prese nted to simplify the CRPS.The simulation results on a benchmark show that rail pressure tracks the setpoint accurately even with some perturbations.Profiting from the conciseness of PFC algorithm,the controller can compute the online solution in a short time,which makes it possible to realize the strategy on a fast response system.
文摘Objective: The aim of this study was to assess the relationship of blood pressure variability (BPV) and heart rate variability (HRV) to investigate the effect of baroreflex function on blood pressure variability. Methods: This study consisted of 111 subjects, including 32 normotensives and 79 hypertensives. All the subjects were given two concurrent tests: 24-hour Holter ECG and ambulatory blood pressure monitoring. According to standard deviation of normal-to-normal sinus RR intervals (SDNN) derived from the Holter ECG, the hypertensives were divided into two groups: an HRV normal group with SDNN > 100 ms and an HRV abnormal group with
文摘HPP (high pressure processing) is one of the novel technologies to produce microbiologically safe food. HPP is a non-thermal food processing method, wherein the food is subjected to a very high pressure ranging between 100-800 MPa in order to prevent undesirable chemical and microbiological reactions, and hence, prolong the shelf-life. HPP is also called as "high hydrostatic processing, ultra-high pressure processing or isostatic processing". In dairy products, HHP has the potential to modify the functional properties of proteins, polysaccharides and alter biochemical reactions without significantly affecting the nutritional and sensory properties. HPP treatment induces significant changes in milk components particularly in proteins (whey proteins and caseins), as well as on their applicability in innovative dairy productions. HPP influences technological properties of various milk products such as firmness, water-holding capacity of the gel and network structure, cheese yield, rennet coagulation time and ripening.
基金supported by the Guangxi Natural Sci-ence Foundation(Grant Nos.2025GXNSFAA069277 and GuikeAD23026204).
文摘Laves-phase are among the most abundant groups of alloys with chemical formula AB_(2),known for their hightemperature strength and potential application in hydrogen storage.The Laves-phase generally acts as a strengthening agent,which enhances the strength and durability of alloys at extreme conditions.Consequently,the properties of Lavesphase alloys at extreme conditions attract wide attention.In this study,we investigated the high-pressure phase diagram of Laves-phase alloy HfZn_(2),and discovered a phase transition from C15(space group Fd3m)phase to C14(space group P63/mmc)phase at a pressure above 20 GPa.Based on ab initio simulations,the mechanical,chemical bonding and superconducting properties of high-pressure phase HfZn_(2)were predicted.The ratio of bulk modulus to shear modulus(B/G),a key indicator of mechanical properties in alloys,increases from 1.86 to 4.09 within the pressure range of 50-250 GPa,indicating excellent ductility of the C14 phase of HfZn_(2)under high pressure.Additionally,Zn gains approximately 0.43 electron from Hf at 10 GPa,and the superconducting critical temperature of HfZn_(2)is estimated to be around 0.55 K at 50 GPa.Given that both C14 and C15 phases are common structures in Laves-phase alloys,elucidating the high-pressure behaviors of C14 and C15 phases of HfZn_(2)will enhance the fundamental understanding of properties and potential applications at extreme conditions of Laves-phase alloys.
文摘Density functional theory(DFT)studies were performed on the lattice parameters,electronic band structure,and optical constants under pressure up to 20 GPa in order to obtain insight into the electronic and optical properties of LiZnAs.The calculated results show LiZnAs is a semiconductor with a direct gap of 0.86 eV,which is smaller than the experimental value 1.1 eV.It also indicates that the structural parameters such as lattice parameters and cell volume show inverse relation to the pressure and shows smooth decreasing behavior from 0 to 20 GPa.Meanwhile,the pressure dependence of the electronic band structure,density of states and partial density of states of LiZnAs up to 20 GPa were presented.And we found that the band gap increased with the pressure.Moreover,the evolution of the dielectric function,absorption coefficient a(w),reflectivity R(w),the refractive index n(w),and the extinction coefficient k(w)of LiZnAs under pressure were presented.According to our work,we found that the optical properties of LiZnAs undergo a blue shift with increasing pressure.These results suggest technological applications of such materials in extreme environments.
文摘BACKGROUND Patients with head and neck cancer often develop depressive symptoms during radiochemotherapy due to changes in saliva secretion,radiation-induced oral mucositis,and dysphagia.These symptoms significantly affect quality of life.Although existing nursing interventions provide some relief,they have limitations in improving swallowing function and developing coping strategies.AIM To evaluate the effectiveness of tongue pressure resistance feedback training combined with empowerment education in improving depressive symptoms and swallowing function in patients with head and neck cancer undergoing radiochemotherapy.METHODS This study included 110 patients with head and neck cancer who exhibited depressive symptoms and underwent radiochemotherapy at the Affiliated Hospital of Jiangnan University between January 2021 and December 2023.Patients were randomly assigned to either a reference group or an experimental group,each comprising 55 patients.The reference group received routine care,whereas the experimental group received tongue pressure resistance feedback training and empowerment education.After 6 weeks of continuous intervention,comparisons were made between the two groups regarding depressive symptom scores,swallowing function,coping strategies,and quality of life,both pre-and post-intervention.RESULTS Following the intervention,both groups demonstrated decreased scores for depressive symptoms and swallowing function,with the experimental group showing a significantly greater reduction than the reference group(P<0.05).The experimental group also demonstrated higher confrontation scores and lower avoidance and submission scores for coping strategies than the reference group(P<0.05).Quality of life scores improved in both groups after the intervention,with the experimental group showing markedly higher scores than the reference group(P<0.05).CONCLUSION The combination of tongue pressure resistance feedback training and empowerment education is effective in alleviating depressive symptoms,enhancing swallowing function,optimizing coping strategies,and significantly improving the quality of life of patients with head and neck cancer undergoing radiochemotherapy.This approach shows promise for clinical applications and promotion.
基金supported by the National Natural Science Foundation of China(Grant No.21503077)the Fundamental Research Fund for the Central Universities of China(Grant Nos.2016MS156 and 13MS105)+1 种基金the Technology Research and Development Program of Hebei Province,China(Grant No.13213704)the Program of Study Abroad for Young Teachers by Agricultural University of Hebei
文摘By using the statistical mechanics, the pressure tensor for the multi component fluid mixture is derived. With the help of the classical density functional theory, profiles of the pressure components are calculated, and the influence of the total volume fraction, ratio of volume fraction, and size asymmetry on the pressure are studied. In addition, our results show that for the mixture confined in the hard cavity, the pressure shows a discontinuity near the cavity wall. However, in the soft cavity condition, the discontinuity disappears.
基金Project supported by the Council of Scientific&Industrial Research(CSIR),India
文摘We study the effect of pressure on electronic and thermoelectric properties of Mg_2Si using the density functional theory and Boltzmann transport equations. The variation of lattice constant, band gap, bulk modulus with pressure is also analyzed. Further, the thermoelectric properties(Seebeck coefficient, electrical conductivity, electronic thermal conductivity) have been studied as a function of temperature and pressure up to 1200 K. The results show that Mg_2Si is an n-type semiconductor with a band gap of 0.21 eV. The negative value of the Seebeck coefficient at all pressures indicates that the conduction is due to electrons. With the increase in pressure, the Seebeck coefficient decreases and electrical conductivity increases. It is also seen that, there is practically no effect of pressure on the electronic contribution of thermal conductivity.The paper describes the calculation of the lattice thermal conductivity and figure of merit of Mg_2Si at zero pressure. The maximum value of figure of merit is attained 1.83 × 10^(-3) at 1000 K. The obtained results are in good agreement with the available experimental and theoretical results.