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Diabetic nephropathy (DN) or Diabetic kidney disease (DKD) is one of the major microvascular complications of diabetes mellitus (DM). DN is observed in approximately 20–40% of diabetic patients. DN is also an important risk factor for DM patient’s death. Nowadays, DN has become the leading cause of chronic renal failure (CRF) in most countries without effective therapeutic methods. Recently, the renoprotective effects mediated by vitamin D have been evidenced. Currently available evidence showed that vitamin D is effective in reducing proteinuria in DN patients. A recent meta-analysis demonstrated the therapeutic effect of vitamin D, on urinary albumin excretion, in DN patients. This review summarized the multiple roles of vitamin D in mechanism of renopretective effect of vitamin D to explore much more and effective therapeutic methods for DN.

It remains controversial, whether vitamin D reduces urinary albumin excretion in patients with diabetic nephropathy (DN). This metaanalysis was designed to evaluate the therapeutic effect of vitamin D, on urinary albumin excretion, in DN patients. Electronic databases, including PubMed, Embase, Web of Science, and Cochrane library were searched for randomized controlled trials (RCTs), regarding the effect of vitamin D on urinary albumin excretion in DN patients. The study selection and data extraction were conducted by two reviewers independently, and statistical analysis was performed using RevMan software, version 5.2. A total of nine RCTs including 1547 subjects were qualified. There were 815 participants in the study group and 732 in the control group. The fixed-effect model was used to analyze urinary albumin creatinine ratio (UACR) and urinary albumin excretion ratio (UAER), and the pooled standard mean difference (SMD) was -0.24 (95% CI: -0.39 to -0.09), P = .002, and -0.57 (95% CI: -0.71 to -0.43), P.00001; respectively. These findings indicated that vitamin D-treated patients had a statistically significant reduction in UACR and UAER. High-quality RCTs are still required. DOI: 10.52547/ijkd.7107.

Aquaporins (AQPs) are an essential transmembrane channel protein and have been discovered in many different tissues (e.g., brain, liver, kidney, and intestine) in animals and serve many specialized biological functions. Research shows that AQPs not only carry the transport of water and other small molecules in animals, but also play a crucial role in diarrhea, constipation, stress, and immunity. Currently, the research about AQPs mainly focuses on the excavation of the water channel structure and function. Additionally, researchers are using knockout mice to construct a channel protein deletion model to explore its mechanism of action on human health as well as exploring the impact of AQPs on livestock health. This paper reviews research progress on understanding AQPs in animal health, especially the impact of aquaporin on livestock health and its nutritional regulation. We also present a bioinformatics method that was used to predict the homology between livestock, poultry, and mouse AQPs genes and proteins. This research provides a theoretical reference for AQPs in animal nutrition research and scientific application.

With the continuous development of bone tissue engineering, the importance of immune response in bone tissue regeneration is gradually recognized. The new bone tissue engineering products should possess immunoregulatory functions, harmonizing the interactions between the bone's immune defense and regeneration systems, and promoting tissue regeneration. This article will interpret the relationship between the bone immune system, bone tissue regeneration, as well as the immunoregulatory function of bone biomaterials and seed stem cells in bone tissue engineering. This review locates arears for foucusing efforts at providing novel designs ideas about the development of immune-mediation targeted bone tissue engineering products and the evaluation strategy for the osteoimmunomodulation property of bone biomaterials.

The present work developed a three-equation local thermal non-equilibrium (LTNE) model to model the initial effect on the internal thermal conduction in the solid phase of porous medium. The two energy equations in the original LTNE model were extended with a third equation to govern the dimensionless thermal penetration depth for the internal thermal conduction in the solid phase, I , which can describe the initial effect. The model was validated by comparisons between an analytical solution of the I equation and exact solutions of thermal conduction problems and between the macro-scale and the pore-scale numerical simulations. The comparisons demonstrate that the three-equation LTNE model is more accurate than the two-equation LTNE model with a constant I during the initial period. An important similarity number, η , is obtained for the enhanced geothermal system (EGS) heat extraction problem from the dimensionless three-equation LTNE model, which measures the internal thermal conduction effect in the solid phase of a porous medium. The initial effect in the EGS heat extraction can be neglected for η

Transpiration cooling is an effective way to protect high heat flux walls from ablation in spaceflight vehicles. Water is an effective transpiration coolant owing to its large latent heat. This study experimentally investigated transpiration cooling with phase change of sintered bronze porous plates in a wind tunnel with an inlet temperature of 800 K and a Reynolds number of 45000. The study investigated the effects of the coolant injection ratio and particle diameter of the sintered porous media on the transpiration cooling efficiency. The results showed that the location of the phase change depended on the coolant injection ratio. The average cooling efficiency and maximum temperature increased as the particle diameter of the sintered bronze porous plate was reduced from 600 μm to 200 μm. However, the transpiration cooling efficiency significantly decreased when the particle diameter further decreased to 90 μm, due to the vapor-blockage effect. The transpiration cooling was delayed by the vapor-blockage effect with only a small mass flow rate of the liquid coolant. The delay significantly decreased with increasing injection ratio or decreasing particle diameter. The transpiration cooling with phase change was unstable and oscillatory with the oscillation period and amplitude decreasing with decreasing coolant injection ratio or increasing particle diameter of the sintered porous plate.

Solar-driven evaporation is a promising way of using abundant solar energy for desalinating polluted water or seawater, which addresses the challenge of global fresh water scarcity. Cost-effectiveness and durability are key factors for practical solar-driven evaporation technology. The present cutting-edge techniques mostly rely on costly and complex fabricated nanomaterials, such as metallic nanoparticles, nanotubes, nanoporous hydrogels, graphene, and graphene derivatives. Herein, a black nylon fiber (BNF) flocking board with a vertically aligned array prepared via a convenient electrostatic flocking technique is reported, presenting an extremely high solar absorbance (99.6%), a water self-supply capability, and a unique salt self-dissolution capability for seawater desalination. Through a carefully designed 3D structure, a plug-in-type BNF flocking board steam generator realizes a high evaporation rate of 2.09 kg m-2 h-1 under 1 kW m-2 solar illumination, well beyond its corresponding upper limit of 1.50 kg m-2 h-1 (assuming 100% solar energy is being used for evaporation latent heat). With the advantages of high-efficiency fabrication, cost-effectiveness, high evaporation rate, and high endurance in seawater desalination, this 3D design provides a new strategy to build up an economic, sustainable, and rapid solar-driven steam generation system.

With the rapid development of thermal management technology, flow boiling in porous media has been widely used in many applications. Among them, phase-changed transpiration cooling is a potential trend in the field of aerospace thermal protection. However, the dynamic response delay, change in boiling point at low pressure, and vapor blockage effect have resulted in significant challenges to its development, and it is difficult to achieve convergence with such non-linear transport equations. Here, kinetic enthalpy is used to restructure energy equation of multiphase mixture model to improved model convergence and accuracy. This modified equation is capable to consider temperature gradient in the two-phase zone, to eliminate non-physical jump and hold smooth transition between the single-phase and two-phase zone, and to enhance the model efficiency of the algorithm. The model was validated by the experiments and was applied to simulate real phase-changed transpiration cooling conditions without main flow effect. It was shown that at low pressure, the two-phase zone has reversed temperature gradient against single-phase zone, and the non-uniform heat flux applied to the boundary can cause non-uniform distribution of mass flux, which may block the vapor and lead to the failure of thermal protection. Subsequently, three ways are proposed to effectively remove vapor blockage and enhance flow uniformity, which are designing porous plate structure, coordinating mass flux distribution, and dividing reservoir into different chambers according to input heat flux. The better understanding of the response mechanism during dynamic process provides a fundamental knowledge to control methods during phase-changed transpiration cooling.

Enhancing spray cooling with surface structures is a common, effective approach for high heat flux thermal management to guarantee the reliability of many high-power, high-speed electronics and to improve the efficiency of new energy systems. However, the fundamental heat transfer enhancement mechanisms are not well understood especially for nanostructures. Here, we fabricated six groups of nanowire arrayed surfaces with various structures and sizes that show for the first time how these nanostructures enhance the spray cooling by improving the surface wettability and the liquid transport to quickly rewet the surface and avoid dry out. These insights into the nanostructure spray cooling heat transfer enhancement mechanisms are combined with microstructure heat transfer mechanism in integrated microstructure and nanostructure hybrid surface that further enhances the spray cooling heat transfer.

Phase-change heat transfer on nanostructured surfaces is an efficient cooling method for high heat flux devices due to its superior wettability. Liquid droplet spreading and wicking effect then dominate the heat transfer. Therefore, this study investigates the flow behavior after a droplet touches a nanostructured surface focusing on the ZnO nanowire surface with three different nanowire sizes and two array types (regular and irregular). The spreading diameter and the wicking diameter are measured against time. The results show that the average spreading and wicking velocities on a regular nanostructured surface are both smaller than those on an irregular nanostructured surface and that the nanowire size affects the liquid spreading and capillary wicking.

EVA/Poplar wood powders composite foaming materials were prepared from etheylen-vinyl acetate-copolymer (EVA) as matrix, poplar wood powders as filler, azodicarbonamide (AC) as foaming agent, dicumyl peroxide (DCP) as cross-linking agent through the method of compression molding foaming. EVA with 15% VA (EVA 15) was chosen as foaming matrix resin by the rotational rheometer. The results showed that an optimum foaming effect had been gained when the AC and DCP were 11 wt% and 0.9 wt%, respectively. And under the condition, the foam density ascended with the increase of poplar wood powders content, when the content arrived to 30%, the resilience reached up to a maximum of 90.1%. The foam cellular structure was researched by SEM, and it showed that when poplar wood powders content was below 30%, the foam holes appeared round or oval, the holes’ size were rather evenly. And the foam cells became more and more unevenly, even collapsed when poplar wood powders up to the content of 40%.

The heat transfer during spray cooling was studied experimentally using deionized water to investigate the spray characteristics and the differences between spray cooling on smooth and enhanced silicon surfaces with micro-structures (characteristic size 25–200 μm). The spray cooling experiments show that the heat transfer was not significantly greater for the micro-structured surfaces than for the smooth surface in the flooded region, but was much greater in the thin film and partial dryout regions. The micro-structured surface with larger characteristic sizes had a smaller area enhancement factor and worse heat transfer rates. However, on the micro-structured surface with much smaller characteristic sizes, most droplets were not able to completely enter the bottom of the micro grooves since the groove size was smaller than most of the droplets and the heat transfer surface could not be fully wetted. There is an optimal groove depth corresponding to a given droplet parameter, groove width and stud size that gives the best heat transfer rates. The wall temperature increase and the temperature fluctuations are small in the boiling regime as the power increases for the micro-structured surfaces.

As acid rain getting more and more serious, increasing attention is given to environmental effect assessment of uranium tailings under the condition of acid rain. In the paper, influence of acid rain to partitioning coefficient (Kd) of U(VI) in soil was studied, and migration of radionuclide uranium in soil was simulated by computer. The static experiment results showed that the Kd value of U(VI) in soil reaches minimum value when pH is 2.0. When 2.0

In the present study, analytical solutions for thermally developing flows in porous media under local thermal non-equilibrium (LTNE) condition are derived for different fundamental models. The analytical solutions are validated by comparison with the numerical results. Based on the analytical solutions, the local Nusselt number is obtained, and the dimensionless thermal entry length ξ c is predicted. The results are presented in terms of the pertinent physical parameters such as the Biot number and the effective thermal conductivity ratio of the fluid to solid phases.

A two-dimensional (2D) axisymmetric (radial) model, considering the effects of the fluid in annulus and heat transfer with surrounding rocks is developed to investigate the flow and thermal behavior of CO2 in injection well during its geological sequestration. The mass equation, the momentum equations with turbulent model and energy equation are solved both in the wellbore flow direction and the radial direction using computational fluid dynamics (CFD) method. Real-gas properties are employed to ensure the calculation accuracy. The wellhead pressure and bottomhole temperature behavior with injection time are predicted. The impact of natural convection of water in the annulus on flow and thermal behavior of injected CO2 are also studied. Besides, factors impacting the bottomhole temperature of CO2 are analyzed. It is found that the work done by pressure (compressibility), potential energy loss and the heat exchange with surrounding rocks are three major factors leading to an increase in the bottomhole temperature of CO2 comparing to the injection temperature. With an increase in injection mass flow rate, the wellhead pressure decreases firstly and then increases, and the bottomhole temperature of CO2 decreases nonlinearly. However, both of them increase linearly with an increase in the injection temperature. This study may help deepen our understanding of the mechanisms of CO2 injection and generate quantitative information in support of design, monitoring and risk assessment of the CO2 geological sequestration.

The ammonia nitrogen (NH4-N) removal enhanced by biological aerobic filter (BAF) packed with novel micro-mesoporous lightweight zeolite particles (LZP) as carrier. The results showed that the biofilm can quickly grow up using LZP as media in the BAF. HLR of 1.2 was chosen as the optimal value under the average influent NH4+-N concentration of 24.6 mg/L, percent NH4-N removal of 87% and NLR of 0.24 kgN/m3.d was achieved. The kinetic performance of the LZP-BAF indicated that the relationship of NH4-N removal efficiency with the L could be described by an exponential equation (Ce/Ci=exp (-1.24/L0.344)).

A thermal boundary condition model at the boundary adjacent to an impermeable wall was developed for the local thermal non-equilibrium (LTNE) model for convection heat transfer in porous media. The model was validated by comparison with pore-scale numerical simulations and macro-scale LTNE model numerical simulations. The concept of the tangential interfacial thermal resistance was developed to explain the mechanism for the splitting of the heat flux between the solid and fluid phases at the wall.

Numerical investigations of the dynamics and evaporative cooling of water droplets impinging onto heated surfaces can be used to identify spray cooling mechanisms. Droplet impingement dynamics and evaporation are simulated using the presented numerical model. Volume-of-fluid method is used in the model to track the free surface. The contact line dynamics was predicted from a dynamic contact angle model with the evaporation rate predicted by a kinetic theory model. A species transport equation was solved in the gas phase to describe the vapor convection and diffusion. The numerical model was validated by experimental data. The physical effects including the contact angle hysteresis and the thermocapillary effect are analyzed to offer guidance for future numerical models of droplet impingement cooling. The effects of various parameters including surface wettability, surface temperature, droplet velocity, droplet size, and droplet temperature were numerically studied from the standpoint of spray cooling. The numerical simulations offer profound analysis and deep insight into the spray cooling heat transfer mechanisms.

The thermoplastic processing and mechanical properties of starch and polycaprolactone (PCL) composites reinforced by nano-silica (nano-SiO2) were studied. The results showed that the mechanical properties of the starch/PCL blends improved significantly with the increase of PCL. After the addition of nano-SiO2, the mechanical properties of the starch/PCL blends further improved. When the weight percent of nano-SiO2 was 1.8%, the mechanical properties of the SiO2/TPS/PCL composite were most excellent. By comparison with the starch/PCL (50/50) blends, the tensile strength of the SiO2/TPS/PCL composite with 1.8% SiO2 was increased by 20% and the elongation increased by 33%. Moreover, it was confirmed by rheological measurements that nano-SiO2 could interact with the composite materials, which results in the improvement of the mechanical strength of the TPS/PCL composites.

In the southwest region of Shandong province, villagers spontaneously adopt various ways to resist the cold climate in winter. In this paper, first we selected three typical rural residences in the region as case buildings. The three residences respectively use different heating ways for better indoor thermal environment, honeycomb briquette, Kang and furnable-heating. Then, we measured and compared the heat and moisture parameters of indoor and outdoor environment of the three residences. Finally, with the results of measurement and comparison, we proposed some methods to improve indoor thermal environment of rural residences, and economical ways of heating to enhance quality of villagers life, and provide technical support for new rural construction.

The ubiquitous discrepancies between predicted and actual outcome of energy efficiency improvement have attracted much attention of the Chinese experts in the field of household energy efficiency. But few people in China realize that it is rebound effect that induces such discrepancies, which at present has been widely accepted in the developed countries. First, in this article the definition and formation process of the rebound effect in the household sector have been described. Then, a high rebound effect of at least more than 30% and more than 50% has been perceived through the combination of the actual situation of China and the experience of other countries. Finally, the influence of the rebound effect in the household sector has been proven negative on the energy demand and energy security of China.

Using 2.5-μm monodisperse polystyrene as seeds, ethylene glycol dimethylacrylate (EDMA) as crosslinking agent, toluene and cyclohexanol as porogen, one-step of seed swelling polymerization method was used for preparing monodisperse beads. Then, the monomer of N -isopropylacrylamide was polymerized on the surface of monodisperse beads to prepare a 7.0-μm monodisperse thermosensitive chromatographic stationary phase. The stationary phase was prepared by very simple one-step seed swelling polymerization, and the bonding capacity of thermosensitive monomer was controlled easily according to the amount between thermosensitive monomer and crosslinker. The stationary phase was evaluated by determining its separation ability and the effect of temperature on retention of proteins. The dynamic protein loading capacity of the synthesized stationary phase was 32.3 mg g −1 . In the hydrophobic interaction chromatographic model, five standard proteins can be separated by the stationary phase, and Cyt-C, β -lact, Rnase-A can be effectively separated by changing the temperature.

An average Reynolds equation considering the effects of a pad’s annular grooves and surface roughness is developed in this study to examine mixed lubrication in the chemical mechanical polishing (CMP) of a copper-film silicon wafer. This equation is obtained on the basis of the principle that the pressure gradients and volume flow rates in the direction normal to the border of a groove and a plateau as well as on two sides of the border must be equal. The continuities of volume flow rates and hydrodynamic pressure on two sides of the border as well as in the direction normal to the border of a groove and a plateau are satisfied in order to develop this Reynolds equation. The removal rate model is obtained by taking the concentration of active abrasives in the slurry and the pad grooves into account. Theoretical results are also shown in order to investigate the effects of changing the groove depth and width on the removal rate and the nonuniformity of a copper-film wafer. The application of concentric grooves in general can lower the suction pressure (negative pressure) formed between the pad and the wafer, elevate the wear rate, and reduce the nonuniformity. However, the influences of the groove depth on wear rate and nonuniformity become insignificant when the depth is excessively large. The removal rate is reduced by increasing the groove width such that it finally approaches to the result of a nongrooved pad.

1-octene-3-ol, the major flavoring substance in Agaricus bisporus, is formed by the reaction of linolenic acid in the presence of enzyme. By adding sunflower oil hydrolysate rich in linolenic acid into the system, we enhanced the flavor formation, then extracted flavors with ethanol while treating them with complex enzymes, later using spray drying to produce a microencapsulated powder flavor. The experiment on flavor enhancement showed that the enhancement effect reached its maximum when the pH is 6.5, temperature is 35 °C and mixed fatty acid is 0.3%.The experiment on the encapsulation of flavor showed the best ratio of the carriers is (calculated according to the weight of fresh mushroom): soybean hydrolyzing protein 10%, Arabic gum 1%, dextrin 15%. The most suitable process was a feed temperature, air inlet and air outlet temperature during spray drying of 50–60, 130–140 and 70–80 °C respectively.

Computational models have shown that purely statistical knowledge about words' linguistic contexts is sufficient to learn many properties of words, including syntactic and semantic category. For example, models can infer that "postman" and "mailman" are semantically similar because they have quantitatively similar patterns of association with other words (e.g., they both tend to occur with words like "deliver," "truck," "package"). In contrast to these computational results, artificial language learning experiments suggest that distributional statistics alone do not facilitate learning of linguistic categories. However, experiments in this paradigm expose participants to entirely novel words, whereas real language learners encounter input that contains some known words that are semantically organized. In three experiments, we show that (a) the presence of familiar semantic reference points facilitates distributional learning and (b) this effect crucially depends both on the presence of known words and the adherence of these known words to some semantic organization.

The heat transfer during spray cooling was studied experimentally using deionized water to investigate the spray characteristics and the differences between spray cooling on a smooth silicon surface and nano- and hybrid micro/nano-structured surfaces. The spray cooling experiments show that the heat transfer rates were best for the nano-structured surface, followed by the smooth surface coated with the SiO2 film and the pure silicon surface since the contact angle was smallest on the nano-structured surface and increased on the other two surfaces. The Critical Heat Flux (CHF) was largest for the 25G×25S surface coated with four Carbon Nano Tube (CNT) films with a 75.3% increase over the smooth surface.Copyright © 2013 by ASME

A theoretical effective gas permeability model was developed for rarefied gas flow in porous media, which holds over the entire slip regime with the permeability derived as a function of the Knudsen number. This general slip regime model (GSR model) is derived from the pore-scale Navier-Stokes equations subject to the first-order wall slip boundary condition using the volume-averaging method. The local closure problem for the volume-averaged equations is studied analytically and numerically using a periodic sphere array geometry. The GSR model includes a rational fraction function of the Knudsen number which leads to a limit effective permeability as the Knudsen number increases. The mechanism for this behavior is the viscous fluid inner friction caused by converging-diverging flow channels in porous media. A linearization of the GSR model leads to the Klinkenberg equation for slightly rarefied gas flows. Finite element simulations show that the Klinkenberg model overestimates the effective permeability by as much as 33% when a flow approaches the transition regime. The GSR model reduces to the unified permeability model [F. Civan, “Effective correlation of apparent gas permeability in tight porous media,” Transp. Porous Media 82, 375 (2010)] for the flow in the slip regime and clarifies the physical significance of the empirical parameter b in the unified model.