Longitudinal Pressure Research Articles

Increased Uric Acid, Gamma-Glutamyl Transpeptidase and Alkaline Phosphatase in Early-Pregnancy Associated With the Development of Gestational Hypertension and Preeclampsia.

Background: Previous studies have reported that biomarkers of liver injury and renal dysfunction were associated with hypertensive disorders of pregnancy (HDP). However, the associations of these biomarkers in early pregnancy with the risk of HDP and longitudinal blood pressure pattern during pregnancy were rarely investigated in prospective cohort studies.Methods: A total of 1,041 pregnant women were enrolled in this prospective cohort study. BP was assessed in four stages throughout pregnancy. The following biomarkers were measured at early pregnancy before 18 weeks gestation: lactate dehydrogenase (LDH), aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), uric acid (UA), and estimated glomerular filtration rate (eGFR). Linear mixed-effects and logistic regression models were used to examine the associations of these biomarkers with longitudinal BP pattern during pregnancy and HDP incidence, respectively.Results: In unadjusted models, higher serum UA, GGT, ALP, and LDH levels, as well as lower eGFR and AST/ALT, were associated with higher BP levels during pregnancy and an increased risk of HDP. After adjustment for maternal age, pre-pregnancy BMI and other potential confounders, UA, GGT, ALP, and LDH remained positively associated with both BP and HDP. However, eGFR and AST/ALT were not associated with HDP after adjusting for potential confounders. When including all 6 biomarkers simultaneously in multivariable analyses, increased UA, GGT, and ALP significantly associated with gestational hypertension and preeclampsia.Conclusion: This study suggests that increased UA, GGT, and ALP in early-pregnancy are independent risk factors of gestational hypertension and preeclampsia.

Longitudinal mechanical response of tunnels under reverse faulting and its analytical solution

The number of tunnels crossing fault zones in Western China has inevitably increased. These tunnels would undergo serious damage under the dislocation, especially for the reverse fault condition. Therefore, this study aims to reveal the longitudinal mechanical responses of tunnels under the dislocation of reverse faults by conducting a comprehensive review of available experimental data. The longitudinal deformation modes and longitudinal strain distributions are collected and analyzed. The bending and axial strains along the longitudinal direction are computed and used to highlight the contributions of the bending and axial compression mechanisms. Moreover, the longitudinal rock pressure distributions at the vault and inverted arch are analyzed to support such response mechanisms of tunnels. Finally, a novel analytical solution to the longitudinal mechanical response of tunnels is proposed on the basis of the Pasternak beam model with consideration of the bending and axial compression mechanisms. The key parameters of the solution are discussed, and the solution itself is validated by comparing the analytical results with the experimental data. The outcomes of this work would provide technical support for the design of tunnels crossing active reverse faults.

Heat transfer and skin-friction in a nonequilibrium adverse pressure gradient

The paper presents the results of an experimental study of influence of a weak and moderate nonequilibrium adverse pressure gradient (APG) on the parameters of the dynamic and thermal boundary layers. The Reynolds number based on the momentum thickness at the beginning of the APG region was Re **=5500. The section of the channel with APG was a slotted channel with an opening angle of the upper wall of 0-14°. The values of the relative (referred to the parameters in a zero pressure gradient flow at the same Re **) friction and heat transfer coefficients, as well as the Reynolds analogy factor depending on the longitudinal pressure gradient, are obtained. The values of the relative friction coefficient decreased to cf/cf0 =0.7 and those of the heat transfer to St/St0=0.9. A maximum value of the Reynolds analogy factor (St/St0)/(cf/cf0 )=1.16 was reached for the pressure gradient parameter β=2.9. The ratio of the heat transfer and drag coefficients of the dimpled to smooth surfaces remained approximately constant regardless of the presence or magnitude of a adverse pressure gradient.

Associations of dietary glycemic index and load during pregnancy with blood pressure, placental hemodynamic parameters and the risk of gestational hypertensive disorders

PurposeThe aim of this study was to examine the associations of dietary glycemic index and load with gestational blood pressure, placental hemodynamic parameters and the risk of gestational hypertensive disorders.MethodsIn a population-based cohort among 3378 pregnant Dutch women, dietary glycemic index and load were assessed from food frequency questionnaires at median 13.4 (95% range 9.9–22.9) weeks gestation. Blood pressure was measured in early-, mid- and late-pregnancy. Placental hemodynamic parameters were measured in mid- and late-pregnancy by ultrasound. Data on gestational hypertensive disorders was acquired from medical records.ResultsMean dietary glycemic index (SD) was 58 (3) and mean dietary glycemic load (SD) was 155 (47). Dietary glycemic index was not associated with blood pressure, placental hemodynamic parameters and the risk of gestational hypertensive disorders. Higher dietary glycemic load SDS was associated with a higher diastolic blood pressure in early-pregnancy, remaining after adjustment for socio-demographic and lifestyle factors ((0.98 (95% CI 0.35–1.61) mmHg per SDS increase in glycemic load). No other associations of glycemic load with blood pressure or placental hemodynamic parameters and the risk of gestational hypertensive disorders were present. No significant associations of dietary glycemic index and load quartiles with longitudinal blood pressure patterns from early to late-pregnancy were present.ConclusionWithin this low-risk pregnant population, we did not find consistent associations of dietary glycemic index and load with blood pressure, placental hemodynamic parameters and the risk of gestational hypertensive disorders. Further studies need to assess whether the effects on gestational hemodynamic adaptations are more pronounced among high-risk women with an impaired glucose metabolism.

Equilibration of the Quark-Gluon Plasma at Finite Net-Baryon Density in QCD Kinetic Theory

We explore the out-of-equilibrium dynamics of the quark-gluon plasma at zero and finite net-baryon density based on an effective kinetic theory of quantum chromodynamics (QCD). By investigating the isotropization of the longitudinal pressure, we determine the relevant time and temperature scales for the onset of viscous hydrodynamics and quantify the dependence on the chemical composition of the quark-gluon plasma. By extrapolating our results to realistic coupling strength, we discuss phenomenological consequences regarding the role of the preequilibrium phase at different collision energies.

Association Between Longitudinal Blood Pressure Trajectory and the Progression of Chronic Kidney Disease: Results From the KNOW-CKD.

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Performance analysis of cross-flow forward osmosis membrane modules with mesh feed spacer using three-dimensional computational fluid dynamics simulations

This study presents a three-dimensional computational fluid dynamics (CFD) model to characterize the effect of mesh feed spacer's geometry on the performance of cross-flow forward osmosis (FO) membranes. The performance of FO membranes against various spacer's geometrical parameters are investigated in terms of permeate water flux, reverse solute flux, concentrative external concentration polarization (CECP) on the membrane, mass transfer coefficient, and longitudinal pressure drop of the feed channel. Also, the membrane support layer is explicitly modeled as a porous medium; the relation between the internal and external concentration polarization phenomena, under different spacer's geometrical variables, is exhibited for different porosities. Our results reveal that the feed spacer's geometrical parameters affect the performance of FO membranes by influencing the volume of the low-circulation or dead zones, and the shear rate on the membrane active layer. The CECP modulus is mainly dominated by the reverse solute flux and the volume of the dead zone on the membrane, while the mass transfer coefficient and the longitudinal pressure drop are more impacted by the exerted shear stress on the membrane. Furthermore, the results of our model demonstrates that the reduction of internal concentration polarization results in an increase in CECP and a magnified impact of the spacer's geometry on the CECP modulus.

Joint modeling of blood pressure measurement and survival time of hypertension patients

Hypertension is a chronic disease that has a major health problem over the centuries due to its significant contribution to the global burden. The objective of this study was to examine the association of survival time and longitudinal Systolic Blood Pressure (SBP) measurement and finding potential barrier that affects SBP measurement and the survival time of hypertension patients. The study considered a cohort of 318 hypertension patients who were aged 18 years or older and were under follow-up from January 1, 2012, to February 30, 2020, at Arba Minch General Hospital. To analyze the data we employed linear mixed effect model, Weibull model, and joint modeling approach for longitudinal and survival data. The results from joint model analysis indicate that systolic blood pressure measurement is significantly associated with survival time of hypertension patients. The results from the longitudinal sub-model reveals that alcohol use, Khat intake, smoking tobacco, stages of hypertension diseases, adherence to treatment, related diseases, and family history had statistical significant relationship with mean change in the sqrt{SBP} measurement. Furthermore, from the survival sub-model, we found the survival probability of hypertension patients was determined by family history, stages of hypertension disease, related diseases, and smoking tobacco. The analysis suggests that there is a strong association between SBP measurement and survival time of hypertension patients. Thus we recommend aggressive work by all concerned bodies towards awareness creation about the effect of potential barriers.

Preparation of long-lasting electret fiber felt by centrifugal air-assisted spinning process and electret post-treatment

The electret ultra-fine fiber filter material is prepared by the centrifugal airflow-assisted process. Moreover, the material can be used in the field of air filtration. A longitudinal air pressure draft sprinkler and a refined centrifugal spinning jet were designed to improve the fiber quality. According to different process parameters, in order to optimize the process of preparing ultra-fine fiber by centrifugal spinning, including the mass fraction of SiO2 (0%, 0.5%, 1%, and 1.5%), the effect of draft pressure (0, 0.05, and 0.15 MPa) on the diameter and morphology of the fiber was investigated. In addition, the effect of air pressure on the diameter and morphology of the fiber was investigated. The effects of key process parameters within the range of common production parameters on fiber quality and fiber morphology were expounded. For the prepared fiber felt, a preliminary test of the physical properties related to the molecular structure and filtration performance of the material was carried out, including the FTIR test and surface contact angle test of the material. After that, we carried out electret treatment of the ultra-fine fiber felt prepared by the centrifugal airflow-assisted process. Besides, we compared the surface electric potential and stability of the fiber felt by the needle electret process and wire electret process, respectively. Finally, the key physical properties of the filter media were tested. In addition, the filtration efficiency and resistance indices of the fiber felt prepared with different parameters were compared. Moreover, the effects of fiber morphology and the electret process on the performance of the filter felt were obtained. The study can provide new ideas and references for the preparation of electret ultra-fine fiber filter media.

Association between ibrutinib treatment and hypertension

BackgroundIbrutinib is a tyrosine kinase inhibitor most commonly associated with atrial fibrillation. However, additional cardiotoxicities have been identified, including accelerated hypertension. The incidence and risk factors of new or worsening...

Longitudinal In-Bed Pressure Signals Decomposition and Gradients Analysis for Pressure Injury Monitoring.

Pressure injury (PI) is a major problem for patients that are bound to a wheelchair or bed, such as seniors or people with spinal cord injuries. This condition can be life threatening in its later stages. It can be very costly to the healthcare system as well. Fortunately with proper monitoring and assessment, PI development can be prevented. The major factor that causes PI is prolonged interface pressure between the body and the support surface. A possible solution to reduce the chance of developing PI is changing the patient’s in-bed pose at appropriate times. Monitoring in-bed pressure can help healthcare providers to locate high-pressure areas, and remove or minimize pressure on those regions. The current clinical method of interface pressure monitoring is limited by periodic snapshot assessments, without longitudinal measurements and analysis. In this paper we propose a pressure signal analysis pipeline to automatically eliminate external artefacts from pressure data, estimate a person’s pose, and locate and track high-risk regions over time so that necessary attention can be provided.

Effect of adding carbon nanotubes into the matrix material on the buckling behavior of glass/epoxy composite plates: An experimental study

In this research, buckling of polymer matrix composite plates containing unidirectional glass fibers under in-plane pressure load is investigated. Moreover, the effect of adding carbon nanotubes as reinforcement into the matrix material on the critical buckling load of composite plates is studied. Using hand lay-up method, rectangular glass/epoxy composite plates with and without carbon nanotubes were fabricated. 0.25, 0.5 and 1.0 weight percent of carbon nanotubes were added to the epoxy resin and composite plates were subjected to the longitudinal in-plane pressure load. The plates were tested under fix ended boundary conditions utilizing Instron hydraulic universal testing machine. Based on the results, adding 0.5 weight percent of carbon nanotubes has the most influence on the critical buckling load of the plates. Results show that adding 0.5 weight percent of carbon nanotubes into the matrix material increases the critical buckling load of the carbon nanotubes /glass/epoxy plate more than two times with respect to that of glass/epoxy composite plate. Furthermore, when the carbon nanotubes weight percent reaches 1 %, because of carbon nanotubes agglomeration, carbon nanotubes are not dispersed well into the epoxy resin and the critical buckling load of the composite plate decreases. To validate the results, buckling analysis of glass/epoxy composite plate was done in Abaqus finite element software. Finite element models confirm the experimental results obtained.

Dynamic spreading characteristics of droplet impinging soybean leaves

The study on the deposition efficiency of pesticide droplets on soybean leaves can provide the basis for reducing pesticide quantity and increasing pesticide efficiency during the application of soybean plant protection machinery. The movement behavior of droplet impinges on the plant leaf surface is affected by many factors, among which the most important and the easiest to adjust are spray droplet size and impingement velocity. By changing the droplet size and impact velocity and using Fluent simulation software, the pesticide droplet hitting the soybean leaf surface was simulated and a test platform was established to verify the simulation results. The conclusions are as follows: The longitudinal roughness of soybean leaves is higher than the transverse roughness, the longitudinal pressure of soybean leaves is higher than the transverse pressure during the impact process, and the velocity of droplet spreading along the longitudinal is lower than that of spreading along the transverse; although soybean leaf surface has high adhesion, droplet losses still exist when droplet impact velocity is relatively high. The maximum spreading diameter of the droplet increases first and then decreases with the increase of impact velocity. At the same time, the maximum spreading diameter of droplet increases with the increase of particle size. The droplet deposition was best at 1.34 m/s impact velocity and 985 μm particle size. This conclusion can provide optimal operation parameters for soybean plant protection operation which can be used to guide soybean plant protection operation, improve control effect, reduce quantity and increase efficiency. Keywords: soybean, deposition efficiency, Fluent, droplet impact, spreading features, dynamic DOI: 10.25165/j.ijabe.20211403.6274 Citation: Li H, Niu X X, Ding L, Tahir A S, Guo C L, Chai J J, et al. Dynamic spreading characteristics of droplet impinging soybean leaves. Int J Agric & Biol Eng, 2021; 14(3): 32–45.

Mean Arterial Pressure and Chronic Kidney Disease Progression in the CKiD Cohort.

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Longitudinal Blood Pressure Patterns From Mid- to Late Life and Late-Life Hearing Loss in the Atherosclerosis Risk in Communities Study.

Hearing loss is prevalent and associated with adverse functional outcomes in older adults. Prevention thus has far-reaching implications, yet few modifiable risk factors have been identified. Hypertension may contribute to age-related hearing loss, but epidemiologic evidence is mixed. We studied a prospective cohort of 3343 individuals from the Atherosclerosis Risk in Communities study, aged 44-65 years at baseline with up to 30 years of follow-up. Hearing was assessed in late life (2016-2017) using a better-ear audiometric pure tone average (0.5, 1, 2, 4 kHz) and the Quick Speech-in-Noise (QuickSIN) test. Hypertension was defined as systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or antihypertensive medication use. Midlife hypertension was defined by hypertension at 2 consecutive visits between 1987-1989 and 1996-1998. Late-life hypertension was defined in 2016-2017. Late-life low blood pressure was defined as a systolic blood pressure less than 90 mmHg or diastolic blood pressure less than 60 mmHg, irrespective of antihypertensive medication use. Associations between blood pressure patterns from mid- to late life and hearing outcomes were assessed using multivariable-adjusted linear regression. Compared to persistent normotension, persistent hypertension from mid- to late life was associated with worse central auditory processing (difference in QuickSIN score = -0.66 points, 95% CI: -1.14, -0.17) but not with audiometric hearing. Participants with persistent hypertension had poorer late-life central auditory processing. These findings suggest that hypertension may be more strongly related to hearing-related changes in the brain than in the cochlea.

Association between longitudinal blood pressure and prognosis after treatment of cerebral aneurysm: A nationwide population-based cohort study.

High blood pressure is a major risk factor for the development and rupture of cerebral aneurysm. Endovascular coil embolization and surgical clipping are established procedures to treat cerebral aneurysm. However, longitudinal data of blood pressure after the treatment of cerebral aneurysm and its impact on long-term prognosis are not well known. This retrospective cohort study included 1275 patients who underwent endovascular coil embolization (n = 558) or surgical clipping (n = 717) of cerebral aneurysm in 2002-2015 using the nationwide health screening database of Korea. Systolic and diastolic blood pressure of patients were repeatedly obtained from the nationwide health screening program. We performed a multivariate time-dependent Cox regression analysis of the primary composite outcome of stroke, myocardial infarction, and all-cause death. During the mean follow-up period of 6.13 ± 3.41 years, 89 patients suffered the primary outcome. Among the total 3546 times of blood pressure measurement, uncontrolled high blood pressure (systolic ≥140 mmHg or diastolic ≥90 mmHg) was 22.9%. There was a significantly increased risk of primary outcome with high systolic (adjusted HR [95% CI] per 10 mmHg, 1.16 [1.01-1.35]) and diastolic (adjusted HR [95% CI] per 10 mmHg, 1.32 [1.06-1.64]) blood pressure. High blood pressure is prevalent even in patients who received treatment for cerebral aneurysm, which is significantly associated with poor outcome. Strict control of high blood pressure may further improve the prognosis of patients with cerebral aneurysm.

Abstract 068: Hypertension And Longitudinal Changes In Cardiac Structure And Function In The Hispanic Community Health Study/Study Of Latinos: Echocardiographic Study Of Latinos (Echo-SOL) Ancillary Study

Introduction: Hypertension, one of the most modifiable risk factors of heart disease, induces cardiac remodeling and worsens myocardial function prior to the development of clinical symptoms. Using a comprehensive cohort of Hispanic/Latino adults, we assessed cardiac structure and function, in relation to hypertension, and the longitudinal impact of blood pressure control. Hypothesis: If baseline hypertensive adults are stratified by longitudinal blood pressure (BP) control, there will be differences in the progression of cardiac structure and function parameters. Methods: The Echo-SOL Ancillary Study provided serial comprehensive echocardiographic assessments of Hispanic adults aged 45-74 years. They were arranged into two groups based on the presence of baseline hypertension (>140/90mmHg). Linear regression models were used to estimate the association between baseline BP properties and the longitudinal change in echocardiogram parameters. We then subdivided each group based on whether the they maintained BP control (<140/90mmHg) on follow up and used linear regression models to test for significance among the mean longitudinal change of echocardiogram parameters. All analyses accounted for the complex sampling design of HCHS/SOL and Echo-SOL. Results: There was a total of 1818 adults at baseline, with 1643 obtaining serial echocardiograms an average of 4.3 years later, mean age of approximately 56 years. Among all adults, baseline pulse pressure was significantly associated with a longitudinal increase in left ventricular (LV) end diastolic volume (β=0.13, p=0.02), whereas the change in LV mass index longitudinally decreased with baseline diastolic BP (β=-0.14, p<0.01). When isolating the subgroup defined as hypertensive at baseline, the adults who had uncontrolled BP on follow up had a greater absolute increase in the average E/E’ ratio and greater decrease in average E’ velocity, 0.95±0.08 and -0.96±0.06 respectively, compared to the adults with controlled BP 0.04±0.07 and -0.74± 0.04 respectively (p<0.01). In addition, the controlled BP group had a greater absolute reduction in LV end-diastolic volume of 6.94mL than those with uncontrolled BP, 4.60mL (p<0.01). Conclusions: Our study is the first to study the association of longitudinal impact of blood pressure control with cardiac structure and function in Hispanic/Latino adults. We found that higher baseline brachial BP properties were associated with reduced in LV mass index and increased LV end diastolic volumes. Among the baseline hypertensive adults, there was a significantly higher progression in diastolic dysfunction among the participants who had poor BP control, but those with controlled BP on follow up had greater LV enlargement. Despite these differences, both subgroups ultimately showed a collective progression in diastolic dysfunction and a decrease in end-diastolic volume over time.

Cardiovascular Risk Factor Trajectories Since Childhood and Cognitive Performance in Midlife: The Cardiovascular Risk in Young Finns Study.

Cardiovascular risk factors, such as high blood pressure, adverse serum lipids, and elevated body mass index in midlife, may harm cognitive performance. It is important to note that longitudinal accumulation of cardiovascular risk factors since childhood may be associated with cognitive performance already since childhood, but the previous evidence is scarce. We studied the associations of cardiovascular risk factors from childhood to midlife, their accumulation, and midlife cognitive performance. From 1980, a population-based cohort of 3596 children (3-18 years of age) have been repeatedly followed up for 31 years. Blood pressure, serum lipids, and body mass index were assessed in all follow-ups. Cardiovascular risk factor trajectories from childhood to midlife were identified using latent class growth mixture modeling. Cognitive testing was performed in 2026 participants 34 to 49 years of age using a computerized test. The associations of the cardiovascular risk factor trajectories and cognitive performance were studied for individual cardiovascular risk factors and cardiovascular risk factor accumulation. Consistently high systolic blood pressure (β=-0.262 SD [95% CI, -0.520 to -0.005]) and serum total cholesterol (β=-0.214 SD [95% CI, -0.365 to -0.064]) were associated with worse midlife episodic memory and associative learning compared with consistently low values. Obesity since childhood was associated with worse visual processing and sustained attention (β=-0.407 SD [95% CI, -0.708 to -0.105]) compared with normal weight. An inverse association was observed for the cardiovascular risk factor accumulation with episodic memory and associative learning (P for trend=0.008; 3 cardiovascular risk factors: β=-0.390 SD [95% CI, -0.691 to -0.088]), with visual processing and sustained attention (P for trend<0.0001; 3 cardiovascular risk factors: β=-0.443 SD [95% CI, -0.730 to -0.157]), and with reaction and movement time (P for trend=0.048; 2 cardiovascular risk factors: β=-0.164 SD [95% CI, -0.318 to -0.010]). Longitudinal elevated systolic blood pressure, high serum total cholesterol, and obesity from childhood to midlife were inversely associated with midlife cognitive performance. It is important to note that the higher the number of cardiovascular risk factors, the worse was the observed cognitive performance. Therefore, launching preventive strategies against cardiovascular risk factors beginning from childhood might benefit primordial promotion of cognitive health in adulthood.

Clustering Longitudinal Blood Pressure Trajectories to Examine Heterogeneity in Outcomes Among Preeclampsia Cases and Controls.

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Shear-friction behavior of concrete-to-concrete interface under direct shear load

Shear transfer at concrete-to-concrete interfaces under direct shear is of great significance to the performance of concrete structures. In this study, a series of direct shear specimens with concrete-to-concrete interfaces were designed by considering the normal pressure, longitudinal reinforcement, and coupling effects. Adding reinforcement or normal pressure increased the interface cracking stress, ultimate shear strength, and residual shear strength, and changed the brittle behavior of the bonding interface to a gradual strength degradation mode. However, an increase in the normal pressure from 4 to 8 MPa only slightly improved the elastic stiffness and plastic ductility of the direct shear specimens. Furthermore, comparing the observed ultimate strengths with the calculated ultimate strengths of three models in main codes, it was shown that all calculated strengths were conservative. During the shear-slip process, among cohesion, friction, and dowel action, the friction was the most affected property during the direct shear process. In the final residual stage, the ratios of cohesion, friction, and dowel action were found to be similar, and no significant relationship was observed between the longitudinal reinforcement and normal pressure before the ultimate shear stress was reached. However, after the ultimate shear stress was reached, the interaction was found to improve the shear resistance at the concrete-to-concrete interface, thereby improving the ductility and interface shear performance.