Average Pressure Research Articles

Experimental and numerical investigation on heat transfer analysis of square slotted pin-fin heat sinks

This paper introduces two novel designs of pin-fin heat sink (PHFS), namely the inline slotted pin-fin (ISP) and the V-shaped slotted pin-fin (VSP), to address rapid heat dissipation for one central/graphics processing unit (CPU/GPU) in a single-phase liquid cooling system. Experimental and numerical investigations are conducted to observe the effect of heat transfer for non-slotted and slotted pin-fin heat sinks under different Reynolds numbers (225-720) and heating powers (90-120 W). Parameters such as average wall temperature, Nusselt number, thermal resistance, pressure drop, and hydrothermal performance factor are evaluated. Comparative analyses show that the slotted pin-fin heat sinks exhibit higher Nusselt numbers (Nu) and lower thermal resistance (Rth) levels than that in the non-slotted pin-fin heat sinks, particularly at lower Reynolds numbers. At the Reynolds number 225 and power of 120 W, the inline and V-shaped slotted pin-fin heat sinks experience a 13.98% and 19.69% increase in Nu and a 12.65% and 15.41% reduction in Rth compared to the non-slotted one, respectively. The V-shaped slotted pin-fin heat sink achieves more than 5 ∘C reduction in the maximum wall temperature than the non-slotted one. The slotted structure reduces pressure drop losses by minimizing dead flow areas on one hand. On the other hand, the inclined slots generate vortices behind the fins, increase shear-induced mixing and thus improve the force convection cooling performance.

Set of heart failure early mortality prevention methods

Heart failure is a common chronic disease with a poor prognosis that often ends in death. The research thus aims to thoroughly investigate ways in which the prognosis of heart failure could be improved. For this purpose, a 9-month study was conducted with a group of people who followed the Mediterranean diet, and the effects of this diet on the cardiovascular system and the state of the body as a whole were assessed. The study found that adherence to the principles of the Mediterranean diet improved the quality of life of patients, according to the quality-of-life questionnaire (the average score was 81.3 at the beginning of the study and 87 points at the end of the study), and the level of adherence to the Mediterranean diet in the study group increased from 30 points to 39.7, according to the MedDietScore (MDS) scale. There was also an improvement in appetite and sleep quality. A decrease in the average blood pressure in the group was recorded (from 140/95 to 137/88 mmHg). It was found that due to proper nutrition, the participant’s Body Mass Index (BMI) was reduced (from 31.2 kg/m2 to 29.6 kg/m2), and the percentage of overweight people in the study group was also reduced from 44% to 26%. It was noted that no deterioration in heart failure class or functional class was recorded during the study. The left ventricular ejection fraction remained unchanged.

Does Elevated Mean-Arterial Pressure Lead to Better Outcomes in Degenerative Cervical Myelopathy?- A Prospective, Pilot Randomized Control Trial.

Randomized Control Trial. DCM refers to compression of spinal cord either due to static/dynamic causes or commonly, a result of combination of both. Number of variables exist, which determine prognosis post-surgery. Role of intra-operative blood pressure has not been analyzed in depth in current literature. Elevating MAP post SCI is widely practiced and forms a recommendation of AANS/CNS Joint Committee Guidelines. This led us to investigate role played by elevated MAP during surgery for DCM, in order to optimize outcomes. This prospective randomized comparative pilot study was conducted at a tertiary care spine centre. 84 patients were randomly divided in two groups. Group 1 had intra-operative MAP in normal range. Group 2, had intra-operative BP 20 mmHg higher than preoperative average MAP with a variation of + 5mmHg. Outcomes were recorded at 3 months, 6 months and 1 year by mJOA, VAS and ASIA scale. Neurological improvement was documented in 19/30 (63.3%) patients of hypertensive group compared to 16/30 (53.3%) patients of normotensive group. Improvements in mJOA scores were better for hypertensive group during the 1-year follow-up. Improvement in VAS scores were comparable between two groups, but at 1-year follow-up the VAS score of hypertensive groups was significantly lower. MAP should be individualized according to preoperative average blood pressure assessment of patient. Keeping intraoperative MAP at higher level (preoperative MAP + 20mmHg) during surgery for DCM can result in better outcomes.

Fitwalking: A New Frontier for Kidney Patients. A Center' s Experience.

Physical inactivity is common in patients with chronic kidney disease (CKD) and is an important modifiable risk factor for mortality, morbidity, and reduced quality of life. The present single-centre pilot study evaluated the possibility of performing structured physical exercise using a specific walking model, Fitwalking, in a population of patients with CKD and, according to the American College of Rheumatology guidelines, also in a population with immuno-rheumatological disease. Patients were recruited from the nephrology, haemodialysis, peritoneal dialysis, transplantation, and immuno-rheumatology outpatient clinics. After general and functional clinical evaluation and exercise prescription at the Department of Sports Medicine, we performed scientifically proven tests on CKD (Six-minute walk test and Sit to stand test), before and after the Fitwalking technique training course, and again after 6 and 12 months, to evaluate its effectiveness and identify any critical issues. We enrolled 80 patients, (41 males, 51.2%), mean age 53±12 years; the clinical data showed statistically significant improvements in systolic, average, and differential blood pressure, average speed, and physical strength. Participants also adapted to muscle fatigue, experienced a reduction in BMI with stable lean mass and reduced fat mass, and reported improved perceptions of physical and mental health, and quality of life. All enrolled patients successfully completed the process. A specific prescription was used that provided health education and allowed for the implementation of structured physical activity that could be performed safely and independently even after the training period. The activity was sustainable thanks to the training of in-house medical and nursing staff, demonstrating that it is possible to overcome this type of barrier to physical activity in CKD and in immuno-rheumatological patients.

Adaptive non‐invasive ventilation treatment for sleep Apnea

AbstractThe purpose of this study was to investigate the effectiveness of two non‐invasive mechanical ventilation (NIV) modalities to treat sleep apnea: (1) Average Volume Assured Pressure Support (AVAPS) NIV, and (2) Pressure Support (PS) NIV with Continuously Calculated Average Required Ventilation (CCARV). Two detailed (previously developed and tested) simulation models were used to assess the effectiveness of the NIV modalities. One simulated subjects without chronic obstructive pulmonary disease (COPD), and the other simulated patients with COPD. Sleep apnea was simulated in each model (COPD and Non‐COPD), and the ability of each NIV modality to normalize breathing was measured. In both NIV modalities, a low level continuous positive airway pressure was used and a backup respiratory rate was added to the algorithm in order to minimize the respiratory work rate. Both modalities could help normalize breathing in response to an episode of sleep apnea within about 5 min (during which time blood gases were within safe limits). AVAPS NIV and PS NIV with CCARV have potential value to be used for treatment of sleep apnea. Clinical evaluations are needed to fully assess the effectiveness of these NIV modalities.

Acute hemodynamic effects of the Marshall-Plan ablation on left and right atrial pressure: does 'respecting atrial physiology' prevent stiff left atria? A retrospective single- center analysis

Abstract Introduction Stiff left atrium (STILA)-syndrome is a relevant concern after extensive ablation in the left atrium (LA) e.g. in persistent atrial fibrillation (AF). STILA often causes disabling heart failure symptoms worse than the initial arrhythmia symptoms. Therefore preventing adverse ablation-induced hemodynamic effects is of utmost concern. Methods This single-center study retrospectively analyzed data from 89 consecutive patients who underwent biatrial ablation for AF following the Marshall-Plan between February 2022 and November 2023. The procedures included ablation of the CTI and PVI where necessary followed by ablation of a LA roof line and ablation of the lateral mitral isthmus after previously performed ethanol ablation of the vein of Marshall. This lesion set is considered to maintain physiological activation of the LA. This study evaluates acute hemodynamic changes following the Marshall-Plan. Invasive hemodynamic measurements of mean left and right atrial pressure, as well as A- and V-waves were performed in all patients before and after the ablation. We assessed the acute changes of atrial hemodynamics in these procedures. Continuous data are given as mean ± standard deviation, categorical data are expressed as number and percentages. Differences between groups were determined by Student’s t-test, chisquare-test, and Fisher’s exact test using SPSS software. A p-value of <0.05 was deemed significant. Results The patients' mean age was 70.1 ± 7.5 years and 39.0% were female. Mean BMI was 28.9 ± 5.2 kg/m². Procedures were performed under general anesthesia (with a PEEP of 5.5cmH2O (2-10 cmH2O)) and took 181 minutes on average. Left atrial mean pressure averaged at 15.7mmHg before the procedure. The overall average change of left atrial mean pressure was +1,8mmHg. The average change in left atrial A- and V-Wave amounted to -1.9mmHg and -0.9mmHg respectively. The pre-procedural average right atrial mean pressure was 12.1mmHg. Right atrial mean pressure inclined by +1.6mmHg. The average change in right atrial A- and V-Wave was +0.6mmHg and +1.1mmHg respectively. The i.v. administered volume averaged 1900 ± 285ml. 3.3% of patients showed an increase of mean LA-pressure >9mmHg. Those patients tended to be older (74.3years), were all male (100%) and had a higher BMI (31.5 kg/m²) as well as higher amount of i.v. administered volume (2333ml) and a longer procedure (213min). Discussion Complex and extensive biatrial ablation following the Marshall-Plan does not lead to acute significant increases in left or right atrial pressures. The administered i.v. volume might explain the slight increases observed. In our observation, the rate of significant increases in LA-pressure is low. This suggests that disrupting the (left) atrial activation pattern might play a role in the development of diastolic dysfunction and thereby STILA-syndrome. Respecting atrial physiology may be beneficial for preventing adverse hemodyamic changes after ablation.

Study on multi‐cycle gas‐water displacing mechanism in underground gas storage of low‐permeability reservoir based on PNM

AbstractA deep understanding of the pore‐scale multi‐cycle two‐phase seepage mechanism of gas‐water systems in low‐permeability reservoirs is crucial for enhancing oil and gas recovery and optimizing the operating conditions of underground gas storage. A pore network model was reconstructed using micro‐CT images of low‐permeability core samples from the Dagang Oilfield, China. The mathematical models of gas‐water flow in the pore‐scale models were established based on Poiseuille's law and the quasi‐static displacement theory, considering the gas compressibility and slip effects. The porosity, pore size, absolute permeability, and relative permeability (Kr) of oil‐water and gas‐water were calculated using pore network simulations and validated against experimental benchmark data of the same samples. The effects of multi‐cycle displacement, rock wettability, and average pore pressure on the gas‐water two‐phase flow were simulated and analyzed. The results showed that the relative permeability of gas (Krg) at the same water saturation level significantly increased when the gas compressibility and slip effects were considered. With an increase in the number of gas‐water displacement cycles, Krg at the same water saturation level showed a decreasing trend, indicating a reduction in the gas seepage capability. Krg decreased with increasing water contact angle. With an increase in the average pore pressure, Krg decreased and gradually increased when the average pressure exceeded 25 MPa.

Continuous positive airway pressure treatment in obstructive sleep apnea syndrome patients with hypertension

Aims: To assess the prevalence and general characteristics of obstructive sleep apnea syndrome in patients with hypertension, investigate the relationship between obstructive sleep apnea syndrome and blood pressure, and the effectiveness of continuous positive pressure ventilation treatment after 1 month in hypertensive patients with obstructive sleep apnea. Methods: Cross-sectional descriptive study with follow-up after 1 month in hypertensive patients treated at the Hue University of Medicine and Pharmacy Hospital with respiratory polygraphy from January 2021 to June 2023. Patients were given history, clinical examination, anthropometric measurements, Lipid profile test, intravenous glucose, Epworth scale assessment, CPAP treatment and re-evaluated after 1 month. Results: 134 patients were registered for the study from 01/2021 to 06/2023. Hypertensive patients with OSAS were 73.13%. BMI in the OSAS (+) group was 22.84 ± 3.04 kg/m2 and was statistically significantly greater than the OSAS (-) group: 22.79 ± 3.07 kg/m2 (p<0.05). Neck circumference in the OSAS (+) group was 37.45 ± 2.44 cm, which was statistically significantly larger than the OSAS (-) group: 36.36 ± 1.57 cm (p<0.05). The rate of loud snoring during sleep and excessive daytime sleepiness in the OSAS patient group was statistically significantly higher than in the group without this syndrome (p<0.05 and p<0.01). The average systolic blood pressure in the OSAS (+) group was 154.79 ± 13.32 mm Hg and was statistically significantly higher than the OSAS (-) group (p<0.01). AHI has a moderate positive correlation with systolic blood pressure (r = 0.45, p<0.01) and diastolic blood pressure (r = 0.34, p<0.01). CPAP treatment improved systolic and diastolic blood pressure and symptoms of excessive daytime sleepiness. Conclusion: There is a relationship between obstructive sleep apnea syndrome and hypertension. CPAP treatment improves blood pressure and daytime sleepiness.

Effect of Cavity Shapes on the Lubrication Performance of High Precision Static and Dynamic Thrust Bearing under Eccentric Load

Abstract The oil cavity shapes, which represent the spatial structures for storing lubricant in static and dynamic thrust bearings, and offset distances, defined as the horizontal distances between the load center and the bearing rotational axis under eccentric loads, directly impact the flow mode of lubricant, pressure, and temperature distribution during bearing operation, so these are the key factors that influence the lubrication performance and the accuracy of bearings. The equations for flow and load capacity of the sector, runway, and double rectangular cavities are derived, and mathematical models are established for different cavities at various tilt positions. Then pressure and temperature fields at different offset distances are analyzed. As the offset distances increase, there is a corresponding increase in the maximum pressures within the sector, runway, and double rectangular cavities by 90.5 kPa, 93.3 kPa, and 30.9 kPa, but average pressures show only minor fluctuations. Concurrently, the maximum temperatures within these cavity shapes are observed to increase by 0.5 K, 0.6 K, and 0.8 K, respectively. The results show that appropriate offset distance can improve the lubrication performance. The runway cavity has the highest load-carrying capacity among the three cavity shapes, while the sector cavity experiences the slightest temperature increase. As the temperature increase in all three cavity shapes is small, the runway cavity exhibits superior performance. The error between simulation and experimental results is less than 10%, which verifies the correctness of the simulation method.

Study on heat transfer and pressure steady-state characteristics of a floating nozzle under a moving wall

This work considers the flow field as two-dimensional turbulent flow and studies the steady-state properties of heat transfer and the pressure of the suspension nozzle. An adiabatic wall parallel to the moving wall and two slit entrances at either end of the adiabatic wall make up the rectangular flow field. The SST k-ω\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$k - \\omega$$\\end{document} turbulence model is used in the turbulence computation. Both qualitative and quantitative analyses are conducted on the distribution of the flow field, temperature field, local Nusselt number, local pressure coefficient, average Nusselt number, and average pressure coefficient under various combination conditions. The findings indicate that when the suspension nozzle's flow field varies greatly, wall-jet velocity ratio is 0.1. A rise in Jet inclination angle is not helpful for the wall's suspension, and it has minimal effect on the flow field. The flow field is greatly influenced by separation space-slit width ratio. Larger separation space-slit width ratio values are advantageous for the wall's heat transmission but unfavorable for the wall's suspension. The flow field is most influenced by wall-jet velocity ratio. The wall's ability to convey heat is stronger the higher the wall-jet velocity ratio, but its ability to support weight falls.

Improved Design and Economic Estimation of Cold-End Systems for Inland Nuclear Power Plants

Reserve sites for coastal nuclear power plants are gradually being depleted, prompting a shift towards the development of inland nuclear power stations. A new cooling system based on the integration of multiple cooling sources using a hybrid dry–wet cycle is proposed to achieve a balance between energy and water consumption for inland nuclear power stations. Comparative studies among all the available cooling systems were further conducted to analyze the cooling performance and economic viability. The case study results indicate that, in comparison to relative humidity, the cooling performance and circulating water consumption of cooling systems are more susceptible to changes in dry-bulb temperature. In arid and water-scarce regions, a Combined Natural Draft Hybrid Cooling System generally exhibits a monthly average circulating water consumption rate that is more than 270 kg/s lower than that of the natural draft wet cooling system, with an average monthly back pressure reduction of 0.11 kPa. When the dry-bulb temperature exceeds 13 °C, the net profit of wet cooling surpasses that of hybrid cooling. However, this scenario undergoes a reversal as the dry-bulb temperature decreases and local water prices rise. It is emphasized that hybrid cooling demonstrates minimal impact when subjected to changes in environmental conditions, offering extensive regional applicability.

ROLE OF THE MACHINE LEARNING–DERIVED HYPOTENSION INDEX (HPI) TO CONTAIN INTRAOPERATIVE HYPOTENSION DURING TRANSCATHETER EDGE TO EDGE REPAIR PROCEDURES

Abstract Introduction Percutaneous endovascular valvular interventions can result in profound hemodynamic instability, elevated burden of intraoperative hypotension (IOH) and related postoperative complications: ischemic stroke, acute kidney injury and increased mortality. Machine learning(ML),a branch of Artificial intelligence (AI), can analyze large volumes of data, find associations and allowing predictive rather than reactive interventions. The Hypotension Prediction Index (HPI)a ML derived algorithm,provides a unitless number from 0 to 100, that increases accordingly to the risk of developing a hypotensive event (mean arterial pressure – MAP – < 65 mmHg for more than 1 minute) in the following minutes. The aim of this study is to describe IOH in patients undergoing percutaneous valve repair under general anesthesia treated according to an HPI–based hemodynamic guidance (fig.1). Methods Eligible adult patients undergoing transcatheter valve repair procedures (MitraclipTM, TriclipTM)were included in the study. When HPI value exceeded 85,a proactive individualized treatment protocol to prevent hypotension was provided according to the following modalities (fig. 2). Primary outcome measure was TWA–MAP (time weighted average mean arterial pressure)under the threshold of 65 mmHg. Secondary outcomes were number of patients with at least one hypotensive event, number of events per patient,depth and duration of hypotensive events and area under MAP threshold of 65 mmHg (AUT–MAP < 65). Results Twenty–five consecutive patients were prospectively enrolled and treated. During an average monitoring time per patient of 187 ± 31 minutes, the global burden of hypotension, measured as TWA–MAP < 65 mmHg, was 0.12 [0.02, 0.8] mmHg. Two thirds of the patients(16/25) experienced hypotensive events, with a median number of hypotensive events of 1 [0, 3.25] per patient and about 11% of the time spent < 65 mmHg. Each event lasted 4 [1.7, 8.6] minutes with a MAP of 59 [56, 62] mmHg, leading to a total AUT–MAP < 65 mmHg of 20.3 [3.5, 142.2] mmHg x minutes. The majority of hypotensive events occurred after induction of general anesthesia, while hypotension was rare during the procedure (fig. 3). Conclusions HPI algorithm provides accurate and continuous prediction of impending IOH before its occurrence. Machine learning models,as in the case of HPI, could facilitate the physicians to treat IOH which is a potentially modifiable risk factor for major postoperative complications.

Analysis and Reflection on the Green, Low-Carbon, and Energy-Saving Design of the Super High-Rise Building

Shanghai Tower has become a new landmark of Shanghai. In the current trend advocating green building and energy efficiency, considerations of wind loads and thermal characteristics of the perimeter structure of Shanghai Tower are crucial. This paper conducts comparative simulation studies on the wind environment of Shanghai Tower using Ecotect software, and stress analyses and thermal simulations of the perimeter structure using ANSYS software. The study compared three buildings’ surface wind pressure distributions using models with equal-volume and circular cross-sections. We found that the unique exterior design of the Shanghai Tower results in a more regular and uniform distribution of wind pressure on its surface compared to both circular and square planar models, with a lower average wind pressure value. In addition, the stress analysis results indicate significant differences in deformation and stress distribution between the windward and leeward sides. Enhancing the bending moment detection of the peripheral structure and optimizing the layout of detection points are recommended. Thermal simulation results show excessive heat conduction flux in winter conditions, suggesting optimization using passive energy-saving methods such as light-sensitive thermal insulation materials during winter. This research is a reference for designing other super-tall buildings prioritizing low-carbon energy efficiency and structural safety.

In vitro evaluation of a hybrid negative pressure system for wound therapy.

The objective of this study was to assess whether negative pressure could be maintained accurately and repeatably with a wall-suction-based hybrid negative pressure wound therapy (h-NPWT) system by comparing it with a commercial negative pressure wound therapy (NPWT) device. In vitro experimental study. A commercial NPWT device (control) and three h-NPWT devices, with 0, 3, and 6 meters of additional tubing using the hospital-wall suction (groups 1, 2, and 3 respectively), were applied sequentially to a commercial NPWT dressing on a silicone skin substrate and set to run at a continuous pressure of -125 mmHg. The pressure within the wound space was monitored at 10 second intervals for 24 h. The process was repeated five times for each group. The commercial NPWT device produced an average pressure variance of 3.02 mmHg, and the h-NPWT produced average variances of 4.38, 4.24 and 4.20 mmHg for groups 1, 2 and 3, respectively. All groups produced an average pressure within 0.15 mmHg of -125 mmHg over the 24-hour period, and the h-NPWT systems produced the smallest range with all values remaining within a ±5% variation from -125 mmHg. The h-NPWT system achieved negative pressures that were comparable to those of a commercial control NPWT device. The addition of tubing between the skin substrate and the canister did not affect the pressure applied at the wound site. The h-NPWT device tested in this study can be considered as an alternative for negative wound therapy when a commercial device cannot be used.

Comparison of surgical outcomes between Kahook Dual Blade goniotomy and Trabectome surgery in patients with open-angle glaucoma

Objective: To compare the medium-term therapeutic effects of Kahook Dual Blade (KDB) goniotomy and Trabectome surgery in the treatment of patients with primary open-angle glaucoma (POAG). Methods: This study was a non-randomized prospective interventional controlled clinical study. POAG patients who underwent KDB goniotomy or Trabectome surgery at Beijing Tongren Hospital from May 2017 to April 2022 were enrolled. The definition of successful surgery was postoperative average intraocular pressure (IOP)≤21 mmHg (1 mmHg=0.133 kPa) and IOP decrease≥20%. Follow-up visits were conducted on the 1st day, 1st week, 1st, 3rd and 6th month after surgery. The IOP value, the number of IOP-lowering medications, the proportion of surgical success (average IOP≤21 mmHg at 6 months), and complications were evaluated. Statistical methods included independent sample t-test, Mann-Whitney rank sum test, χ2 test, repeated measures two-factor analysis of variance, Bonferroni, Friedman M test, Wilcoxon, and Log-rank. The Kaplan-Meier method was used to calculate the cumulative success rate of each group. Results: Seventeen male patients (17 eyes) and 10 female patients (10 eyes) were included. The mean age was (39.9±17.7) years old. There were 11 patients in the KDB group and 16 patients in the Trabectome group. There was no significant difference in clinical baseline conditions between the two groups (P>0.05). The IOPs in the KDB and Trabectome groups at postoperative 1 week [(16.6±6.3) and (16.4±4.1) mmHg) and 6 months [(17.8±5.3) and (19.9±4.4) mmHg) were lower than those before surgery [(25.1±9.3) and (27.4±9.1) mmHg) (all P<0.05). There was no significant difference in the overall IOP between groups (P>0.05). The IOP reduction rates in the KDB and Trabectome groups were 23.4% and 19.0%, with no significant difference (P=0.674). The numbers of IOP-lowering medications used in the KDB and Trabectome groups at 3 months [2.0 (1.0, 4.0) and 2.0 (1.0, 2.3)] and 6 months [2.0 (0.0, 4.0) and 2.0 (1.0, 3.0)] after surgery were not significantly different from those before surgery [4.0 (2.0, 4.0) and 3.0 (2.0, 4.0)] (both P>0.05). There was no statistical significance in the overall number of IOP-lowering medications used between the two groups (P>0.05). There was also no statistically significant difference in the proportion of patients with an IOP decrease of≥20% and the proportion of patients whose mean postoperative IOP was≤21 mmHg (all P>0.05). The proportions of IOP≤21 mmHg in the KDB group and the Trabectome group at 6 months after surgery were 81.8% and 68.8% (P>0.05). Serious intraoperative or postoperative complications occurred in neither group. Conclusions: Both KDB trabeculotomy and Trabectome surgery can effectively reduce IOP and have a good safety profile in treating POAG, with the same number of IOP-lowering medications.

Reservoir Quality Under the Control of Gravity Flows in the C7 Member of Yanchang Formation in the Jinghe Oilfield, Ordos Basin, China

The late Triassic sandstone reservoir in the C7 member of the Jinghe oilfield southern Ordos basin is a typical deep-water gravity flow tight oil reservoir. Sedimentary microfacies, physical properties, and petrographic analysis were being examined for quality determination. Pore structure and physical properties data together combined with, thin sections, and scanning electron microscope and core images were used to identify factors controlling reservoir physical properties. The depositional system under debates of different gravity flows including debris flow, seismite slumping, and turbidity flows. Among which sandy debris flow facies shows a better distribution of porosity and permeability followed by seismite-slump, where turbidity facies are the poorest. The petrophysical analysis shows that the study oil interval is a typical tight sandstone reservoir with an average porosity of 9% and permeability average being 0.025mD. The rock classification criteria of the C7 sandstone reveal the sub-categories of lithic feldspar sandstone and feldspar lithic sandstone. Average quartz sandstone contents of 48.25%, average feldspar sandstone content being 25%, and lithic fragments content of 29%. The formation lithology comprises mostly fine-grained sandstone and small pore size, which disclose that the porosity-permeability distribution increases proportional to the average and median pore throat radius, and decreases with average and median pressure. The microfacies distribution shows that the depositional facies controlled physical properties. The sandstone primary pores are affected by the mineral composition of quartz, feldspar, illite, smectite, kaolinite, calcite, and dolomite. Features such as dissolved pores and intergranular pore filling by feldspar, silky-like aggregates of illite-smectite intergranular pore filling and most diagenetic minerals influenced the sandstone pores beside the compaction.

Design, assembly and testing of an upgraded aeroacoustics wind tunnel facility

The Aeroacoustics Laboratory in the Department of Aerospace Engineering at Penn State currently serves several areas of experimental research. Most notable in the laboratory is the Anechoic Chamber of which the Aeroacoustics Wind Tunnel is an integral part. In recent years the dominant areas of research have included model aircraft exhaust jets and model rotors for helicopter applications involving detailed noise experiments. In the jet noise area, the applications have included aircraft in both flyover and take-off configurations. In the flyover application the air flow surrounding the exhaust jet has a significant effect on the radiated noise and must be simulated to produce experimental results that will be most useful in preliminary design of noise suppression applications. The Aeroacoustics Wind Tunnel at Penn State serves the purpose for this simulation. During aircraft take-off, the aircraft airspeed is in a range exceeding 250 ft per second, or Mach number of over M = 0.22. In the years preceding 2022, the velocity of the free jet flow of the Penn State facility was limited to less than 200 ft/sec. This paper reports on a project to design upgrades to the existing wind tunnel to improve the test section flow velocity to values closer to the 250 ft/sec target. The approach began with a preliminary design of the return flow ducting to convert the open jet, open return wind tunnel to a closed return tunnel. The concept is to make use of the flow energy in the exhaust of the tunnel to boost the input energy to the inlet fan that drives the flow to the test section. An integral part of the preliminary design involved making use of an upgraded flow analysis computer code to predict the gain in test section velocity of the new facility. For the available horsepower of two fans in the facility, the configurations of the existing and upgraded wind tunnel were entered into this analysis code based on a quasi-one-dimensional formulation. The code included empirical data formulated to include the various shapes of the components of the tunnels. The relative flow velocities in each section used simple incompressible continuity to calculate all velocities in the component sections. The average dynamic pressure in each section is calculated from the flow (constant) density and the velocity squared. Each section had a non-dimensional pressure loss parameter calculated from empirical data (from the relevant literature). The basic code (using the Excel algorithms) was based on a predictor-corrector concept in which the calculation was initialized with the estimated velocity and pressure of the flow at the entrance to the test section. The loss in each following section is estimated to determine the loss in the total pressure and the cumulated loss compared to the gains made at the two fans in the circuit. The initial guess is adjusted based on the total pressure value at the end of the circuit. During the related experiments, measurements of the total and dynamic pressure were performed at several joints between sections and compared to the values predicted in the analysis code. Various settings of the horsepower of the drive fans were used and the results were compared to flow measurements for the tunnel configurations (predominantly for the open return and closed return tunnel setups available before and after the upgrade project.) Results of the analysis and experiments are presented and analyzed together with the remaining activities planned for the coming months.

Changes in the state of matter of KCIO4 to improve thermal and combustion properties of Al/MoO3 nanothermite

To improve the thermal and combustion properties of nanothermites, a design theory of changing the state of matter and structural state of the reactants during reaction was proposed. The Al/MoO3/KClO4 (Kp) nanothermite was prepared and the Al/MoO3 nanothermite was used as a control. SEM and XRD were used to characterize the nanothermites; DSC was used to test thermal properties; and constant volume and open combustion tests were performed to examine their combustion performance. Phase and morphology characterization of the combustion products were performed to reveal the mechanism of the aluminothermic reaction. The results show that the Al/MoO3/Kp nanothermite exhibited excellent thermal properties, with a total heat release of 1976 J·g− 1, increasing by approximately 33% of 1486 J·g− 1 of the Al/MoO3 nanothermite, and activation energy of 269.66 kJ·mol− 1, which demonstrated higher stability than the Al/MoO3 nanothermite (205.64 kJ·mol− 1). During the combustion test, the peak pressure of the Al/MoO3/Kp nanothermite was 0.751 MPa, and the average pressure rise rate was 25.03 MPa·s− 1, much higher than 0.188 MPa and 6.27 MPa·s− 1 of the Al/MoO3 nanothermite. The combustion products of Al/MoO3 nanothermite were Al2O3, MoO, and Mo, indicating insufficient combustion and incomplete reaction, whereas, the combustion products of Al/MoO3/Kp nanothermite were Al2O3, MoO, and KCl, indicating complete reaction. Their “coral-like” morphology was the effect of reactants solidifying after melting during the combustion process. The characterization of reactants and pressure test during combustion reveals the three stages of aluminothermic reaction in thermites. The excellent thermal and combustion performance of Al/MoO3/Kp nanothermite is attributed to the melt and decomposition of Kp into O2 in the third stage. This study provides new ideas and guidance for the design of high-performance nanothermites.

Clinical Effects of Sildenafil in the Treatment of Congenital Heart Disease with Pulmonary Hypertension

Objective: To analyze the improvement of mean pulmonary arterial pressure and oxygenation index as well as the therapeutic effect of sildenafil treatment in patients with congenital heart disease and pulmonary arterial hypertension. Methods: A total of 104 patients with congenital heart disease and pulmonary arterial hypertension were recruited from February 2023 to January 2024 and grouped into study and control groups using a randomized numerical table, with 52 patients in each group. The study group received sildenafil treatment, while the control group received conventional treatment. The therapeutic effects of both groups were analyzed and compared. Results: The study group had an average pulmonary arterial pressure of 26.23 ± 2.16 mmHg, an oxygenation index of 241.63 ± 4.86, and a total effective treatment rate of 98.08%, which was significantly better than the control group (P &lt; 0.05). Conclusion: By implementing sildenafil treatment for patients with congenital heart disease and pulmonary hypertension, the mean pulmonary artery pressure and oxygenation index of the patients improved significantly, and the effective rate of treatment increased significantly.

“Advocates for Each Other”: The creation and evaluation of a pragmatic peer navigation program for black patients in primary care with uncontrolled hypertension

BackgroundBlack individuals in the U.S. and in our primary care clinic experience worse control of blood pressure compared to White individuals. ObjectiveTo address this inequity, our objectives were to (1) elicit from patients and community members their ideas for barriers and facilitators to blood pressure control; and (2) use their input to design and pilot a navigator program for Black patients in our clinic to improve blood pressure management. Patient involvementWe conducted three focus groups with 27 individuals and identified two main areas of need that informed the peer navigator program: (1) community-based services and (2) skill development for hypertension self-management. MethodsPeer navigators from the Black community called participants at least monthly for 6–12 months and connected them with medical and social services. Available blood pressure data was used as the primary outcome to measure change pre- to post-peer navigation program. ResultsAmong 499 eligible patients in the clinic, 53 (10.6%) enrolled in the peer navigation program. For those with baseline and follow-up blood pressure data, mean systolic blood pressure decreased from 155.9 to 142.4 mmHg after the program (change of −13.6, 95% CI −24.7 to −2.4) for the enrolled patients (N = 17) and from 139.1 to 137.1 mmHg (change of −2.5, −4.8 to 1.9) for unenrolled, comparison patients (N = 183). DiscussionThis community-informed peer navigation program to support Black patients with uncontrolled hypertension led to a 11.1 mmHg greater decrease in average systolic blood pressure for enrolled patients compared to the comparison group. However, the enrolled group started with a significantly higher systolic blood pressure at baseline with more room for improvement. While this study was conducted during the pandemic years, low uptake of this program needs to be addressed in expansion efforts. Practical valueClinic-based peer navigation for hypertension improved blood pressure control and was highly regarded by the subset of enrolled patients. Increasing uptake and sustainable funding for non-billable clinic roles remain areas of need. FundingGrant from the Pacific Hospital Preservation & Development Authority.