Ultrafiltration of α-Lactalbumin Protein: Acquaintance of the Filtration Performance by Membrane Structure and Surface Alteration

α-Lactalbumin is an essential protein with multiple roles in physiological and the nutritional functionalities, such as diabetic prevention, blood pressure stabilization, and cancer cell inhibition. In the present work, polyethersulfone (PES)-based membranes were developed by incorporating Pluronic F127 and carbon nanotubes with single- and multi-walled dimensions (Sw-Cnts and Mw-Cnts) as additives. The resulting membranes were evaluated for use in the filtration of α-lactalbumin protein solution. Four series of membranes, including PES pristine membrane, were fabricated via the phase inversion process. The characteristics of the membrane samples were analyzed in terms of morphology, membrane surface hydrophilicity and roughness, and surface chemistry. The characterization results show that the incorporation of additive increased the surface wettability by reducing the surface water contact angle from 80.4° to 64.1° by adding F127 and Mw-Cnt additives. The highest pure water permeability of 135 L/(m2·h·bar) was also exhibited by the PES/F127/Mw-Cnt membrane. The performance of the modified membranes was clearly better than the pristine PSF for α-lactalbumin solution filtration. The permeability of α-lactalbumin solution increased from 9.0 L/(m2·h·bar) for the pristine PES membrane to 10.5, 11.0 and 11.5 L/(m2·h·bar) for membranes loaded with Pluronic F127, Sw-Cnts, and Mw-Cnts, respectively. Those increments corresponded to 17, 22, and 28%. Such increments could be achieved without altering the α-lactalbumin rejections of 80%. Remarkably, the rejection for the membrane loaded with Sw-Cnts even increased to 89%.

Pengaruh Terapi Bekam Basah terhadap Perubahan Tekanan Darah pada Pasien Hipertensi

Non-Communicable Diseases (PTM) is one of the world's health problems that is still a concern in the world of health because it is one of the causes of death. Hypertension is a condition where systolic blood pressure is 140 mmHg or higher and diastolic blood pressure is 90 mmHg or higher. The cause of hypertension is due to abnormal water and salt retention, sensitivity to angiostensin, obesity, hypercholesteroemia, disturbed emotions / stress and smoking. One of the non-pharmacological therapies that can be used for the management of hypertension is to use wet cupping therapy. The purpose of this study was to analyze the effect of wet cupping on the blood pressure of hypertensive patients.Blood pressure as the dependent variable and wet cupping as an independent variable. This study uses a Pre Experimental Design study with "Two Group Pre Test and Post Test Design". The sample consisted of 20 people with hypertension with 10 respondents in the intervention group and 10 respondents in the control group in the Al-Thaf Nursing home in Jambi City on March to July 2021 with the Purposive Sampling technique. He statistical test carried out is to use paired t-test. From the results obtained p value systolic blood pressure = 0,000 and p value diastolic blood pressure = 0,000.The conclusion of this study is that there is an effect of wet cupping therapy on blood pressure stabilization in hypertensive patients in the city of Jambi

Pressure Stabilization Strategies for a LES Filtering Reduced Order Model

We present a stabilized POD–Galerkin reduced order method (ROM) for a Leray model. For the implementation of the model, we combine a two-step algorithm called Evolve-Filter (EF) with a computationally efficient finite volume method. In both steps of the EF algorithm, velocity and pressure fields are approximated using different POD basis and coefficients. To achieve pressure stabilization, we consider and compare two strategies: the pressure Poisson equation and the supremizer enrichment of the velocity space. We show that the evolve and filtered velocity spaces have to be enriched with the supremizer solutions related to both evolve and filter pressure fields in order to obtain stable and accurate solutions with the supremizer enrichment method. We test our ROM approach on a 2D unsteady flow past a cylinder at Reynolds number 0≤Re≤100. We find that both stabilization strategies produce comparable errors in the reconstruction of the lift and drag coefficients, with the pressure Poisson equation method being more computationally efficient.

Estimation of the reliability of determination of filtering parameters of productive formations using multi-dimensional regression analysis

Determination of reliable values of filtration parameters of productive strata is the most important task of monitoring the processes of developing reserves. One of the most effective methods for solving the problem is hydrodynamic testing of wells using the pressure recovery method, as well as modern methods - the pressure stabilization method and the method based on production analysis (Decline Analyze). This article is devoted to the assessment of the reliability of these three methods in determining the filtration parameters of terrigenous and carbonate productive deposits of oil fields in the Perm Krai. To solve the problem, multivariate regression analysis was used. A series of multidimensional mathematical models of well flow rates was built using filtration parameters determined for each of the methods. It is proposed to consider the filtration parameters included in the models with the maximum statistical estimates of performance as the most reliable. With regard to the fields under consideration, it was found that in terrigenous reservoirs, all three methods demonstrate stable results. In carbonate reservoirs, reliable values of filtration parameters are determined by processing pressure build-up curves. Pressure stabilization and production analysis methods show less robust results and require additional research in order to develop sound recommendations for their practical application. Keywords: permeability; skin factor; pressure stabilization curve; decline analyze; liquid flow rate; geological and technological parameters; oil deposit; carbonate deposits.

Analysis of Dynamic Characteristics of Pressure-Regulating and Pressure-Limiting Combined Relief Valve

Aiming at the problem of the lack of a cooperation mechanism of combined relief valves, this paper proposes a new pressure-regulating and pressure-limiting combined relief valve. Combined with the ordinary relief valve dynamic characteristic analysis method, the dynamic model of the combined relief valve under normal working conditions was established, and its dynamic characteristics were simulated using Simulink. The results showed that the multi-pressure stabilization design of the combined relief valve improves its usability and stability. Under the same structural parameters, the overshoot of the combined relief valve was 5.7%, and the response time was 12 ms, which is better than the ordinary relief valve. Besides, it effectively improves the instability problems, such as the vibration and the large pressure fluctuation of the ordinary relief valve under high pressure and large flow conditions. When the sum of the effective force area on the upper side of the flange of the pressure-regulating valve core and the area of the tail vertebra is equal to the effective force area of the lower side of the flange of the pressure-regulating valve core, the dynamic performance of the relief valve is optimal. For example, if the effective force area under the flange is 1.8 cm2, then the inlet pressure overshoot is 2.8%, and the response time is 10 ms. An appropriate volume of the sensitive cavity, the quality of the valve core, and the fluid resistance of the pressure relief valve are factors that can effectively improve the dynamic performance of the pressure-regulating and pressure-limiting combined relief valve.

Research on Pressure-Retaining Performance of Transfer Device for Abyssal Sediments

In order to retain the activity of microorganisms from abyssal sediment samples, this paper proposes the first device that can be used for the pressure-retaining transfer of seabed sediment samples. The device can transfer sediment from the sampler to the sample processing container and maintain the in-situ pressure of the sample, with the maximum pressure up to 100 MPa. The sample is stirred in the lower cavity of the transfer container and divided into the culture container by pressure difference control. In order to maintain the internal pressure of the device, a pressure stabilization system was designed, and a self-designed conical seal and right-angle combined seal were proposed. The high-pressure test is carried out through the experimental platform, the pressure is maintained for 1.5 h, and the pressure is actively reduced to verify the stability of the pressure stabilization system. The experimental results show that the pressure-retaining performance of the device can meet the transfer of 10,000 m of seabed sediment samples.