Pressure Control Research Articles

Effectiveness of a nurse-led management intervention on systolic blood pressure among type 2 diabetes patients in Uganda: a cluster randomized trial.

Hypertension (HT) is an orchestrator of atherosclerotic cardiovascular disease (ASCVD) in people living with type 2 diabetes (T2D). Control of systolic blood pressure (SBP) and HT as a whole is suboptimal in diabetes, partly due to the scarcity of doctors. While nurse-led interventions are pragmatic and cost-effective in the control of HT in primary health care, their effectiveness on SBP control among patients with T2D in Uganda is scantly known. We evaluated the effectiveness of a nurse-led management intervention on SBP among T2D patients with a high ASCVD risk in Uganda. A two-armed cluster randomized controlled trial compared the nurse-led management intervention with usual doctor-led care. The intervention involved training nurses to provide structured health education, protocol-based HT/CVD management, 24-h phone calls, and 2-monthly text messages for 6months. The primary outcome was the mean difference in SBP change among patients with T2D with a high ASCVD risk in the intervention and control groups after 6months. The secondary outcome was the absolute difference in the number of patients at target for SBP, total cholesterol (TC), fasting blood glucose (FBG), glycated hemoglobin (HbA1C), low-density lipoprotein (LDL), triglycerides (TG), and body mass index (BMI) after the intervention. The study was analyzed according to the intention-to-treat principle. Generalized estimating equations were used to assess intra-cluster effect modifiers. Statistical significance was set at 0.05 for all analyses. Eight clinics (n = 388 patients) were included (intervention 4 clinics; n = 192; control 4 clinics; n = 196). A nurse-led intervention reduced SBP by -11.21 ± 16.02mmHg with a mean difference between the groups of -13.75mmHg (95% CI -16.48 to -11.02, p < 0.001). An increase in SBP of 2.54 ± 10.95mmHg was observed in the control group. Diastolic blood pressure was reduced by -6.80 ± 9.48mmHg with a mean difference between groups of -7.20mmHg (95% C1 -8.87 to -5.48, p < 0.001). The mean differences in the change in ASCVD score and glycated hemoglobin were -4.73% (95% CI -5.95 to -3.51, p = 0.006) and -0.82% (95% CI -1.30 to -0.35, p = 0.001), respectively. There were significant absolute differences in the number of patients at target in SBP (p = 0.001), DBP (p = 0.003), and TC (p = 0.008). A nurse-led management intervention reduces SBP and ASCVD risk among patients with T2D. Such an intervention may be pragmatic in the screening and management of HT/ASCVD in Uganda. Pan African Clinical Trial Registry, PACTR202001916873358, registered on 6th October 2019.

Heavy Metal Exposure-Induced Cardiovascular Diseases: Molecular Mechanisms and Therapeutic Role of Antioxidants.

Globally, cardiovascular diseases (CVDs) are the main cause of mortality every year worldwide. CVD health is influenced by various health factors, such as blood pressure, cholesterol levels, and glucose control. The main risk factors include smoking, physical activity, food intake, and body mass index. Around 90% of CVDs could be prevented by controlling these risk factors. Heavy metals are indigenous to the environment of the earth. However, modern lifestyles have led to the exploitation of our environment by unconstrained use of heavy metals. Though heavy metals are essential components, they are hazardous to humans and living systems due to their persistent and non-degradable nature. The mainpurpose of this study is to provide a literature review on the mechanisms of heavy metals, particularly arsenic, lead, and cadmium, that cause cardiovascular diseases. The major mechanism by which heavy metals result in various modalities of cardiovascular disease is the generation of reactive species and the depletionof the antioxidant reserves inside the biological system. The generation of reactive species gradually leads to the activation of various signaling pathways, resulting in either apoptosis or unrestricted cell growth. These unfavorable conditions result in a state when there is an imbalance between reactive species generation and antioxidant activity. Both endogenously present antioxidants and dietary antioxidants are very much essential in regulating the redox potential of the body. They help in the detoxification and excretion of heavy metals and their metabolites in the biological system. Therefore, recognizing the role of heavy metals in cardiovascular health is crucial for developing preventive strategies and interventions aimed at mitigating their adverse effects on human health.

Northern Pacific sea-level pressure controls rain-on-snow in North America

Northern Pacific sea-level pressure controls rain-on-snow in North America

Updates in the care and management of children and adolescents with systemic lupus erythematosus.

This narrative review offers an update of the most important recent articles published in the previous year of childhood-onset systemic lupus erythematosus (cSLE), focusing on care and management. Age-related disparities may play a significant role in the clinical and laboratory characteristics of cSLE, as well as its performance in distinct classification criteria. Monogenic lupus is associated with higher disease damage scores and mortality rate compared to sporadic cSLE. Adolescent face unique challenges, with comorbid psychiatric diagnosis, low resilience and nonadherence posing relevant challenges. A recent international task force has outlined pivotal principles and points-to-consider for treat-to-target (T2T) in cSLE patients. While the past year did yield new randomized controlled trial for cSLE treatment, publications focused on broader management strategies, including the impact of ultraviolet radiation exposure, immunization, and strict blood pressure control. Additionally, case reports and series have evaluated the efficacy/safety profiles of both available and emerging treatments. Current studies highlighted the various facets of cSLE, epidemiology, clinical, laboratory, classification criteria, adolescent issues, prognosis, surveillance, T2T approach and drug management. Despite notable progress, the scarcity of randomized trials emphasizes the need to delineate safer and more efficacious treatment modalities in cSLE.

Research on Multi-Mode Control of Electro-Hydraulic Variable Displacement Pump Driven by Servo Motor

The electro-hydraulic power source with an electro-hydraulic variable pump driven by a servo motor is suitable for electrified construction machinery. To achieve better energy efficiency in different working conditions, the multi-mode control scheme was proposed for the electro-hydraulic power source. The control scheme includes pressure control, flow control, and torque control modes. The switching rule among the three control modes was formulated based on the minimum pump pressure. The fuzzy PID controller was designed, and a composite flow regulation strategy was formulated, including the load-sensitive adaptive displacement regulation and servo motor variable speed regulation. The AMESim-Simulink co-simulation model of multi-mode control was established. The test platform was built, and the experimental study was carried out. The results indicate that the fuzzy PID control has a shorter response time and a more stable control effect compared with PID control. Additionally, the composite flow regulation strategy improves the flow regulation range by 36% and reduces the flow overshoot by 20% compared with the load-sensitive adaptive displacement regulation. As the main control valve received an opening step signal, the full flow regulation (7~81 L/min) of the power source took approximately 0.5 s to rise and 0.2 s to fall. The relative error of pressure difference for the main control valve was 0.63%. When receiving the pressure and torque step signal, the pump pressure and pump input torque both took approximately 0.45 s to rise and 0.2 s to fall. The relative errors of pump pressure and torque control were 0.2% and 0.16%, respectively. In the multi-mode control, the electro-hydraulic power source could switch smoothly between flow control mode, pressure control mode, and torque control mode. These results provide a reference for the multi-mode control of an electro-hydraulic power source with an electro-hydraulic variable pump driven by a servo motor.

Targeting the sympathetic nervous system with the selective imidazoline receptor agonist moxonidine for the management of hypertension: an international position statement.

Hypertension is often linked with metabolic risk factors that share common pathophysiological pathways. Despite wide-spread availability of multiple drug classes, optimal blood pressure (BP) control remains challenging. Increased central sympathetic outflow is frequently neglected as a critical regulator of both circulatory and metabolic pathways and often remains unopposed therapeutically. Selective imidazoline receptor agonists (SIRAs) effectively reduce BP with a favorable side effect profile compared with older centrally acting antihypertensive drugs. Hard outcome data in hypertension, such as prevention of stroke, heart and kidney diseases, are not available with SIRAs. However, in direct comparisons, SIRAs were as effective as angiotensin-converting enzyme inhibitors, β-blockers, calcium channel blockers, and diuretics in lowering BP. Other beneficial effects on metabolic parameters in hypertensive patients with concomitant overweight and obesity have been documented with SIRAs. Here we review the existing evidence on the safety and efficacy of moxonidine, a widely available SIRA, compared with common antihypertensive agents and provide a consensus position statement based on inputs from 12 experts from Europe and Australia on SIRAs in hypertension management.

Personalized Piezoresistive Anti‐Scar Orthosis with Precise Pressure Monitoring Function Based on Embedded 3D Printing

AbstractHyperplastic scars, especially keloids, have posed a significant clinical challenge due to their high recurrence rate. Compression therapy, a cost‐effective treatment, has demonstrated efficacy in reducing scarring and preventing recurrence. However, the compression methods exhibit limitations in adapting to the complex contours and accurately adjusting the treatment pressure, resulting in unsatisfactory treatment effects. In this study, silicone is chosen as the substrate layer ink, while the conductive ink is developed by incorporating nano‐carbon black into the polymer composite. These are printed alternately within the supported gels to construct an integrated orthotic device with precise pressure control capabilities and complex structures. Results demonstrated the printed orthosis displayed excellent mechanical properties, durability and biocompatibility. It can successfully detect various stress changes with short response times. The utilization of finite element analysis aided in the design of personalized orthosis to achieve optimal pressure for scar treatment. Finally, orthosis‐mediated pressure treatment is performed on rat tail scar models. By monitoring resistance value, it can be inferred whether the treatment pressure applied by orthosis fell within an optimal range. Overall, personalized piezoresistive anti‐scar orthoses offer an accurate and effective treatment method for scar. This innovative approach presents a novel strategy in the realm of personalized scar management.

External Jet Nebulization and Measured Ventilator Performance.

During invasive ventilation, external flow jet nebulization results in increases in displayed exhaled tidal volumes (VT). We hypothesized that the magnitude of the increase is inaccurate. An ASL 5000 simulator measured ventilatory parameters over a wide range of adult settings: actual VT, peak inspiratory pressure (PIP), and time to minimum pressure. Ventilators with internal and external flow sensors were tested by using a variety of volume and pressure control modes (the target VT was 420 mL). Patient conditions (normal, COPD, ARDS) defined on the ASL 5000 were assessed at baseline and with 3.5 or 8 L/min of added external flow. Patient-triggering was assessed by reducing muscle effort to the level that resulted in backup ventilation and by changing ventilator sensitivity to the point of auto-triggering. Results are reported as percentage change from baseline after addition of 3.5 or 8 L/min external flow. For ventilators with internal flow sensors, changes in displayed exhaled VT ranged from 10% to 118%, however, when using volume control, actual increases in actual VT and PIP were only 4%-21% (P = .063, .031) and 6%-24% (P = .25, .031), respectively. Changes in actual correlated closely with changes in PIP (P < .001; R2 = 0.68). For pressure control, actual decreased by 3%-5% (P = .031) and 4%-9% (P = .031) with 3.5 and 8 L/min respectively, PIP was unchanged. With external flow sensors at the distal Y-piece junction, volume and pressure changes were statistically insignificant. The time to minimum pressure increased at most by 8% (P = .02) across all modes and ventilators. The effects on muscle pressure were minimal (∼1 cm H2O), and ventilator sensitivity effects were nearly undetectable. External flow jet nebulization resulted in much smaller changes in volume than indicated by the ventilator display. Statistically significant effects were confined primarily to machines with internal flow sensors. Differences approached the manufacturer-reported variation in ventilator baseline performance. During nebulizer therapy, effects on VT can be estimated at the bedside by monitoring PIP.

Effects of Achieving Rapid, Intensive, and Sustained Blood Pressure Reduction in Intracerebral Hemorrhage Expansion and Functional Outcome.

The time taken to achieve blood pressure (BP) control could be pivotal in the benefits of reducing BP in acute intracerebral hemorrhage (ICH). We aimed to assess the relationship between the rapid achievement and sustained maintenance of an intensive systolic BP (SBP) target with radiologic, clinical, and functional outcomes. Rapid, Intensive, and Sustained BP lowering in Acute ICH (RAINS) was a multicenter, prospective, observational cohort study of adult patients with ICH <6 hours and SBP ≥150 mm Hg at 4 Comprehensive Stroke Centers during a 4.5-year period. Patients underwent baseline and 24-hour CT scans and 24-hour noninvasive BP monitoring. BP was managed under a rapid (target achievement ≤60 minutes), intensive (target SBP <140 mm Hg), and sustained (target stability for 24 hours) BP protocol. SBP target achievement ≤60 minutes and 24-hour SBP variability were recorded. Outcomes included hematoma expansion (>6 mL or >33%) at 24 hours (primary outcome), early neurologic deterioration (END, 24-hour increase in NIH Stroke Scale score ≥4), and 90-day ordinal modified Rankin scale (mRS) score. Analyses were adjusted by age, sex, anticoagulation, onset-to-imaging time, ICH volume, and intraventricular extension. We included 312 patients (mean age 70.2 ± 13.3 years, 202 [64.7%] male). Hematoma expansion occurred in 70/274 (25.6%) patients, END in 58/291 (19.9%), and the median 90-day mRS score was 4 (interquartile range, 2-5). SBP target achievement ≤60 minutes (178/312 [57.1%]) associated with a lower risk of hematoma expansion (adjusted odds ratio [aOR] 0.43, 95% confidence interval [CI] 0.23-0.77), lower END rate (aOR 0.43, 95% CI 0.23-0.80), and lower 90-day mRS scores (aOR 0.48, 95% CI 0.32-0.74). The mean 24-hour SBP variability was 21.0 ± 7.6 mm Hg. Higher 24-hour SBP variability was not related to expansion (aOR 0.99, 95% CI 0.95-1.04) but associated with higher END rate (aOR 1.15, 95% CI 1.09-1.21) and 90-day mRS scores (aOR 1.06, 95% CI 1.04-1.10). Among patients with acute ICH, achieving an intensive SBP target within 60 minutes was associated with lower hematoma expansion risk. Rapid SBP reduction and stable sustention within 24 hours were related to improved clinical and functional outcomes. These findings warrant the design of randomized clinical trials examining the impact of effectively achieving rapid, intensive, and sustained BP control on hematoma expansion. This study provides Class III evidence that in adults with spontaneous ICH and initial SBP ≥150 mm Hg, lowering SBP to <140 mm Hg within the first hour and maintaining this for 24 hours is associated with decreased hematoma expansion.

Efficacy and safety of radiofrequency ablation and laparoscopic adrenalectomy for primary aldosteronism: a meta‑analysis.

To compare the efficacy (including blood pressure, medication reduction, serum potassium, and clinical success) and safety parameters (including operative time, length of hospital stay, blood loss, hypertension crisis rate, and complication rate) of radiofrequency ablation (RFA) and laparoscopic adrenalectomy (LA) in the treatment of primary aldosteronism (PA). Literature search was performed on PubMed, EMBASE, The Cochrane Library (Issue 8, 2023), Web of Science, China National Knowledge Infrastructure, and Wanfang from inception to August 2023. Study selection, data extraction, and risk of bias assessment were performed by two independent reviewers. Quality assessment was conducted using the Newcastle-Ottawa scale. The Stata 12.0 software was used for statistical analyses. Pooled odds ratios (OR) with corresponding 95% confidence interval (CI) were calculated for categorical outcomes, while mean difference (MD) with corresponding 95% CI were calculated for continuous outcomes. A total of 5 studies involving 204 patients (LA, n = 127; and RAF, n = 77) were included. LA had better diastolic blood pressure control than RFA (WMD = 5.19; 95% CI 0.96-9.43); however, the RFA demonstrated better shorter operative time (WMD = - 57.99; 95% CI - 116.54 to 0.57), and shorter length of hospital stay (OR - 1.6; 95% CI - 2.37 to - 0.83) compared to LA. All remaining parameters were comparable between the interventions. While grossly comparable in efficacy as treatment options for PA, RFA may allow for shorter operative time and hospital stay, less intraoperative blood loss, and lower hospitalization costs. However, LA has better diastolic blood pressure control. Even so, we still need larger prospective studies, specifically with comparative hypertension response (short and long term) and number of post-procedural antihypertensive medication requirement.

Effects of incremental peritoneal dialysis with low glucose-degradation product neutral pH solution on clinical outcomes.

Incremental peritoneal dialysis (IPD) could decrease unfavorable glucose exposure results and preserve (RKF). However, there is no standardization of dialysis prescriptions for patients undergoing IPD. We designed a prospective observational multi-center study with a standardized IPD prescription to evaluate the effect of IPD on RKF, metabolic alterations, blood pressure control, and adverse outcomes. All patients used low GDP product (GDP) neutral pH solutions in both the incremental continuous ambulatory peritoneal dialysis (ICAPD) group and the retrospective standard PD (sPD) group. IPD patients started treatment with three daily exchanges five days a week. Control-group patients performed four changes per day, seven days a week. A total of 94 patients (47 IPD and 47 sPD) were included in this study. The small-solute clearance and mean blood pressures were similar between both groups during follow-up. The weekly mean glucose exposure was significantly higher in sPD group than IPD during the follow-up (p < 0.001). The patients with sPD required more phosphate-binding medications compared to the IPD group (p = 0.05). The rates of peritonitis, tunnel infection, and hospitalization frequencies were similar between groups. Patients in the sPD group experienced more episodes of hypervolemia compared to the IPD group (p = 0.007). The slope in RKF in the 6th month was significantly higher in the sPD group compared to the IPD group (65% vs. 95%, p = 0.001). IPD could be a rational dialysis method and provide non-inferior dialysis adequacy compared to full-dose PD. This regimen may contribute to preserving RKF for a longer period.

Enabling Uniform and Accurate Control of Cycling Pressure for All‐Solid‐State Batteries

AbstractAll‐solid‐state batteries are emerging as potential successors in energy storage technologies due to their increased safety, stemming from replacing organic liquid electrolytes in conventional Li‐ion batteries with less flammable solid‐state electrolytes. However, all‐solid‐state batteries require precise control over cycling pressure to maintain effective interfacial contacts between materials. Traditional uniaxial cell holders, often used in battery research, face challenges in accommodating electrode volume changes, providing uniform pressure distribution, and maintaining consistent pressure over time. This study introduces isostatic pouch cell holders utilizing air as pressurizing media to achieve uniform and accurately regulated cycling pressure. LiNi0.8Co0.1Mn0.1O2 | Li6PS5Cl | Si pouch cells are fabricated and tested under 1 to 5 MPa pressures, revealing improved electrochemical performance with higher cycling pressures, with 2 MPa as the minimum for optimal operation. A bilayer pouch cell with a theoretical capacity of 100 mAh, cycled with an isostatic pouch cell holder, demonstrated a first‐cycle Coulombic efficiency of 76.9% and a discharge capacity of 173.6 mAh g−1 (88.1 mAh), maintaining 83.6% capacity after 100 cycles. These findings underscore the effectiveness of isostatic pouch cell holders in enhancing the performance and practical application of all‐solid‐state batteries.

An Enhanced Vacuum-Assisted Resin Transfer Molding Process and Its Pressure Effect on Resin Infusion Behavior and Composite Material Performance

In this paper, an enhanced VARTM process is proposed and its pressure effect on resin infusion behavior and composite material performance is studied to reveal the control mechanism of the fiber volume fraction and void content. The molding is vacuumized during the resin injection stage while it is pressurized during the mold filling and curing stages via a VARTM pressure control system designed in this paper. Theoretical calculations and simulation methods are used to reveal the resin’s in-plane, transverse, and three-dimensional flow patterns in multi-layer media. For typical thin-walled components, the infiltration behavior of resin in isotropic porous media is studied, elucidating the control mechanisms of fiber volume fraction and void content. The experiments demonstrate that the enhanced VARTM process significantly improves mold filling efficiency and composite’s performance. Compared to the regular VARTM process, the panel thickness is reduced by 4% from 1.7 mm, the average tensile strength is increased by 7.3% to 760 MPa, the average flexural strength remains at approximately 720 MPa, porosity is decreased from 1.5% to below 1%, and the fiber volume fraction is increased from 55% to 62%.

Effect of Structural Parameters on Output Characteristics of a Novel Self-Supplied Aviation Intelligent Pump

The aviation intelligent pump system is an effective solution to aircraft hydraulic systems’ inefficient power consumption and temperature increase. A self-supplied aviation intelligent pump (SAIP) has a high power-to-weight ratio and compact structure, making it the optimal choice for an intelligent pump. To analyze the output characteristics of a novel aviation intelligent pump, it is crucial to establish an accurate mathematical model that describes its dynamic characteristics. This can be achieved by analyzing the working principle and exploring the influence of critical parameters. The paper introduces the composition and working principle of a self-supplied electro-hydraulic servo variable displacement pump. It then establishes a mathematical model of the whole pump, with a detailed analysis and modeling of the critical variable mechanism and the swash plate assembly’s load moment. A simulation model was created to examine the impact of crucial structural parameters, such as the offset spring’s stiffness and control piston’s diameter, on the output characteristics of the intelligent pump. An experimental platform was also constructed, and the experimental results confirm the accuracy of the SAIP model presented in this paper. The investigation of the output characteristics fully reveals the dynamic performance of the SAIP. This provides the basis for the subsequent design of high-performance flow and pressure control strategies and aids in researching intelligent aircraft hydraulic systems.

Study on the Fracture of a Shield Segment in a Fully Excavated Hard Rock Section under the Influence of Construction Loads

In this paper, the initiation of the fracture of a segment caused by the pressure of the jack and other factors during shield construction is discussed. Based on the Rots model in the finite element software Diana 10.4, the fracture width is solved. Combined with in situ measurements, the mechanisms of concrete fracturing of a segment under external loads, such as the jack thrust deflection angle and uneven jack thrust caused by the changes in the segment due to the upward buoyancy and shield attitude, are studied; additionally, the occurrence conditions and engineering control measures for segment fracture are summarized. The results show that when the attitudes of the shield and segment are identical, the total thrust of the shield is recommended not to exceed 21,000 kN, and is strictly limited to 24,000 kN. When the attitude inclination angle between the shield machine and the segment is less than 1°, the impact on the segment quality is small. When the inclination angle reaches 2°, the total thrust of the shield is recommended not to exceed 16,000 kN, and is strictly limited to 18,000 kN. When the inclination reaches 3°, a fracture is easily produced. When the total thrust is 19,000 kN, it is recommended that the loading increase or decrease in the left and right four grippers should not exceed 20%, and they are prohibited to exceed 30%. The fracture width increases exponentially with the increase in misalignment between adjacent segment rings. These research results provide a theoretical basis for jack pressure control during shield construction.

A non-invasive method to monitor respiratory muscle effort during mechanical ventilation.

This study introduces a method to non-invasively and automatically quantify respiratory muscle effort (Pmus) during mechanical ventilation (MV). The methodology hinges on numerically solving the respiratory system's equation of motion, utilizing measurements of airway pressure (Paw) and airflow (Faw). To evaluate the technique's effectiveness, Pmus was correlated with expected physiological responses. In volume-control (VC) mode, where tidal volume (VT) is pre-determined, Pmus is expected to be linked to Paw fluctuations. In contrast, during pressure-control (PC) mode, where Paw is held constant, Pmus should correlate with VT variations. The study utilized data from 250 patients on invasive MV. The data included detailed recordings of Paw and Faw, sampled at 31.25Hz and saved in 131.1-second epochs, each covering 34 to 41 breaths. The algorithm identified 51,268 epochs containing breaths on either VC or PC mode exclusively. In these epochs, Pmus and its pressure-time product (PmusPTP) were computed and correlated with Paw's pressure-time product (PawPTP) and VT, respectively. There was a strong correlation of PmusPTP with PawPTP in VC mode (R² = 0.91 [0.76, 0.96]; n = 17,648 epochs) and with VT in PC mode (R² = 0.88 [0.74, 0.94]; n = 33,620 epochs), confirming the hypothesis. As expected, negligible correlations were observed between PmusPTP and VT in VC mode (R² = 0.03) and between PmusPTP and PawPTP in PC mode (R² = 0.06). The study supports the feasibility of assessing respiratory effort during MV non-invasively through airway signal analysis. Further research is warranted to validate this method and investigate its clinical applications.

PREVALENCE OF INSULIN RESISTANCE IN PREDIABETIC PATIENTS WITH HYPERTENSION

stage between normal people and patients with type 2 diabetes mellitus. The pathogenesis is mainly related to insulin resistance (IR). The relationship between IR and hypertension is a complex and multifactorial phenomenon. We examined the prevalence of IR in prediabetic patients with hypertension. Objectives: The present study aimed to determine the incidence of IR according to the HOMA2 model in the group of prediabetes with hypertension, compared with the group of prediabetes without hypertension. Subjects and Methods: The cross-sectional study described and collected data from 191 people with prediabetes from February 2023 to September 2023 at the Examination Department of Cho Ray Hospital. IR was determined by the HOMA2 calculator, using a threshold of 1.29 for IR. Prediabetes and hypertension were diagnosed according to ADA 2022 and ISH 2020 criteria, respectively. Results: The number of subjects selected to analyze the data was 179 patients, including 89 prediabetes patients without hypertension and 90 prediabetes patients with hypertension. The prevalence of IR in the overall prediabetes group was 56.9%. The prevalence of IR in the hypertensive group was 66.7%, higher than the non-hypertensive group at 47.2%, which was statistically significantly different. The values of the index in HOMA2 did not differ statistically significantly between non-hypertensive and hypertensive populations. Conclusions: The prevalence of IR in prediabetes patients with hypertension was 66.7%, greater than the prediabetes patients without hypertension of 47.2%, P = 0.013. Attention should be paid to good control of blood pressure in patients with prediabetes.

Selective hydrogenation of unsaturated vinyl ethers in two‑chamber gauge‐reactor

A pressure gauge was incorporated into a two‐chamber glass H‐tube to continuously monitor the pressure inside a reactor when working with gases. The ex situ generated H2, D2, acetylene and CO2 were tested in pressure gauge reactors, and calibration curves were plotted. A series of unsaturated compounds with two or more double C=C bonds accessible for hydrogenation were synthesized for hydrogenation. The hydrogenation proceeded well due to constant pressure control, and the desired products were isolated in good yields. The same hydrogenation procedures were then carried out using steel autoclaves to verify the results and compare them. Surprisingly, almost the same results were obtained, confirming the effectiveness of self‐made glass reactors. The hydrogenation mechanism was further investigated using D‐labeled reagents. The kinetics of hydrogenation was studied both in manometric glass reactors and in steel autoclaves, which showed a similar nature of the main process in both reaction units. Thus, the created reactors can be effectively used in barometric transformations instead of steel autoclaves in appropriate cases.

New concepts in the physiopathology of hypertension. Purinergic receptors

Hypertension is a major risk of morbidity and mortality in patients when it is uncontrolled. In spite of improved therapies currently available for blood pressure control, their complications are far away from being accomplished. Therefore, chronic renal failure is frequently observed in hypertensive patients. Thus, insights on mechanisms that may contribute to arterial pressure control should be studied to prevent life-threatening cardiovascular disorders. Purinergic receptors have been recognized in the physiopathology of hypertension; this review summarizes their participation in the renal abnormalities of the kidney in hypertension. Several studies have suggested the activation of renal purinergic receptors under an elevated interstitial ATP milieu as a fundamental pathway that leads to generation and maintained hypertension. Elevated ATP concentration alters fundamental mechanisms involved in the long-term control of blood pressure such as pressure natriuresis, autoregulation of glomerular filtration rate and renal blood flow, as well as increased tubule-glomerular feedback responses, overall, these alterations decrease sodium excretion; in addition, the expression of ATP receptors is modified. Under a genetical background, ATP induces the production of vasoactive compounds, decreases renal function and induces tubulointerstitial injury before glomerular damage. Simultaneously, a deleterious interaction between angiotensin II and purinergic receptors lead to the progression of renal damage.

Ground fracturing of multi-strata for strong ground pressure control in extra-thick coal seams with hard roofs: Numerical simulation and case study

Strong ground pressure in the mining field is the key factor restricting safe mining of hard-roof mining areas. A hard roof combines high strength with a large breakage step, and the large breakage area would easily cause ground pressure disasters in the working face with gradual breakage of multi-hard rock strata. The study investigated the characteristics of the dynamic hazards under multi-hard rock strata conditions. The method of graded ground fracturing of multi-hard rock strata was proposed to control the ground pressure, and the characteristics of the bending strain energy release of the rock strata breakage and instability under the condition of equivalently decreasing the thickness of the strata by ground fracturing were theoretically analyzed. A numerical simulation model of weakening in multi-strata rock formations by fracturing was established, and the structural characteristics of rock strata breakage under the ground fracturing effects were analyzed. The results showed that the breakage characteristics of the overlying hard roofs were altered by ground fracturing, the bearing properties of the fractured rock strata were drastically reduced, while the effect of the breakage and destabilization of the rock strata was subsequently weakened. The ground fracturing practice of the L1 and L2 hard rock strata in the Tashan Coal Mine, China, taken as a case study, revealed that the cracks extension length reached approximately 220 m, and the crack’s width was 30 ∼ 120 m. During the working face was mined in the area covered by the cracks, the average supports resistance was reduced by 21 %, the rate of rib spalling was reduced by 23 %, greatly alleviating the intensity of ground pressure in the working face. The application of ground fracturing technology to multi-hard rock strata effectively weakened the hard rock strata, improving the ability of ground pressure control.