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1.
Despite advances in the field, hemoincompatibility remains a critical issue for hemodialysis (HD) as interactions between various human blood constituents and the polymeric structure of HD membranes results in complications such as activation of immune system cascades. Adding hydrophilic polymer structures to the membranes is one modification approach that can decrease the extent of protein adsorption. This study conducted molecular dynamics (MD) simulations to understand the interactions between three human serum proteins (fibrinogen [FB], human serum albumin, and transferrin) and common HD membranes in untreated and modified forms. Poly(aryl ether sulfone) (PAES) and cellulose triacetate were used as the common dialyzer polymers, and membrane modifications were performed with 2-hydroxymethyl methacrylate (HEMA) and poly (2-methoxyethyl acrylate) (PMEA), using polydopamine-assisted co-deposition. The MD simulations were used as the framework for binding energy simulations, and molecular docking simulations were also performed to conduct molecular-level investigations between the two modifying polymers (HEMA and PMEA) and FB. Each of the three proteins acted differently with the membranes due to their unique nature and surface chemistry. The simulations show PMEA binds less intensively to FB with a higher number of hydrogen bonds, which reflects PMEA's superior performance compared to HEMA. The simulations suggest PAES membranes could be used in modified forms for blood-contact applications as they reflect the lowest binding energy to blood proteins.  相似文献   
2.

In this paper, an experimental study, aimed at delaying flow separation on a high-lift device using a pulsed blowing excitation method, is reported. The main objective of this investigation was to evaluate a new pulsed jet generation strategy to enhance flow control performance. In these experiments, two types of signal waveform were implemented to produce the unsteady blowing; a simple square-wave excitation signal for the first case, and a burst modulated excitation signal for the second case. The signal modulation was the first time to be used for a fast-switching solenoid valve actuator. Another objective of this study was to evaluate a new arrangement of the jet exit slots, in the form of a vortex generator which was employed for the first time on the high-lift device. For this purpose, a NASA SC(2)-0714 airfoil with a single slotted flap was employed. The vortex generator jets emanated from the shoulder of the trailing-edge flap with excitation frequencies from 40 to 1000 Hz. Pressure distribution around the model and wake total pressure deficit were measured. The results indicated that ejection from vortex generator slot pairs was able to prevent flow separation completely in most conditions. These measurements revealed that the burst modulated excitation signal was accompanied by more aerodynamic improvements and less air consumption relative to the simple pulsed jet excitation signal. In the best flow control mode, the results showed about a 53% increase in the value of the suction pressure peak on the flap and a 38% decrease in drag with a reduction in total pressure loss.

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3.
Celikbas  Olgur  Liang  Li  Sadeghi  Arash  Sharif  Tirdad 《数学学报(英文版)》2023,39(3):439-458
Acta Mathematica Sinica, English Series - In this paper we are concerned with absolute, relative and Tate Tor modules. In the first part of the paper we generalize a result of Avramov and...  相似文献   
4.
Journal of Thermal Analysis and Calorimetry - For the first time, double phosphates(V) Zn3Cr4(PO4)6 and Mg3Cr4(PO4)6 were synthesized by non-waste solid-state reaction, performed in the temperature...  相似文献   
5.
Strontium-based medications, such as strontium ranelate, have been suggested to have therapeutic effects in patients with osteoporosis. Strontium salts available off-shelf in stores across North America are assumed to provide similar effects as strontium ranelate and thus should lead to similar distributions of elemental strontium incorporated in bone. The objective of this study was to compare the spatial distribution of strontium in animal bones following the administration of strontium ranelate and strontium citrate. Seventeen-week-old Sprague–Dawley rats were split into three groups over 10 weeks and given 625 mg/kg/day of strontium ranelate and 676 mg/kg/day of strontium citrate; the control group received no additional supplementary strontium. The humeri were collected from all animals, and strontium distribution was mapped using 2D micro-XRF and 3D dual energy K-edge subtraction (KES) imaging. 2D and 3D elemental mapping methods demonstrated that strontium delivered during treatment by both salts had the same spatial distribution. 3D elemental strontium maps of treated animal bones showed that strontium was largely observed in the trabecular regions under the epiphyseal (growth) plate. The thickness of the strontium layers in both the strontium ranelate and strontium citrate sample was not significantly different (p = .9201). 2D micro-XRF and 3D dual-energy KES images effectively elucidated the spatial distribution of elemental strontium in calcified tissue. These methods provide a novel approach to evaluating the potential efficacy of strontium supplements in the treatment of osteoporosis.  相似文献   
6.
Research on Chemical Intermediates - In this paper, a rapid, easy and very efficient method for the synthesis of bis(pyrazolyl)methanes has been reported in the presence of nickel–guanidine...  相似文献   
7.
Transport in Porous Media - In this study, a novel triple pore network model (T-PNM) is introduced which is composed of a single pore network model (PNM) coupled to fractures and micro-porosities....  相似文献   
8.
9.
Journal of Thermal Analysis and Calorimetry - In this study, the efficacy of incorporating phase change material (PCM) into the building walls on the annual heat transfer reduction is examined....  相似文献   
10.
Journal of Thermal Analysis and Calorimetry - Artificial neural network/kriging interpolation method optimization method which is evaluated concerned the hybrid nanofluid composed of iron oxide...  相似文献   
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