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This paper aims to analyze product life cycle, introduce green design concept and integrate it into product design so as to establish feasibility path combining with China’s national condition. Through case analysis, five green design principles of green co-creation, material reduction, green packaging, material replacement and design from identical material were summarized according to the five attributes of figment, product, commodity, article and waste. The whole process was analyzed with the case of indigo T-shirt. The five design principles can provide guidance for all aspects of the product, ensure the sustainability of the product, realize the optimization and upgrading of the product and achieve the goal of carbon peak and carbon neutrality.

This paper aims at exploring the feasible path of building rural handicraft brand under the concept of green design. Taking the intangible cultural heritage handicrafts in Sansui County, Qiandongnan, Guizhou Province as the core, the demand factors among craftsmen, left-behind laborers, designers, market and government were analyzed. Based on the green design concept, the brand of “Zhi Bu Zhi Zhu” was created in a green way. In the design practice, the pictures of cultural images with brand characteristics are collected as samples, and the symbols with the highest recognition of images are obtained through cultural image cognition experiments, which are applied to the brand design together with the symbols of brand personality elements. In today’s competitive market, the concept of green design is combined with brand building. Through brand green co-creation design, more social responsibilities and obligations are borne, and material reduction design and material substitution design are integrated into the whole brand process so as to create a green, natural and healthy rural handicraft brand, expand brand connotation and value and enhance brand market competitiveness.

In the whole process of geological prospecting, based on the principles of fine design, fine construction, and fine interpretation and the technical route of “expanding on the surface, constructing on points, combining points and surfaces, and focusing on the breakthrough”, more and more geophysical prospecting methods are comprehensively applied in the work of geological prospecting, because a single geophysical method is very limited for following interpretation. For example, the geology, geochemical exploration, anti-interference electrical method, gravity, magnetic method are carried out to optimize multiple potential ore-forming favourable ore sites. By summarizing the collected geological data and a large amount of basic geological work and physical and chemical exploration work, the survey results can be obtained by using a comprehensive geophysical method. In this paper, an application of the comprehensive geophysical method on geological survey by a case study in a China mining area.

We have developed a new and fast MATLAB algorithm for predicting absolute permeability. The developed tool relies on measuring the connectivity of pores in a given 3D microcomputed tomography rock image. An index of pore connectivity is evaluated. After a calibration step, the developed index is used to estimate permeability in a variety of rocks with challenging pore structures (e.g., complex carbonate formations). The developed algorithm was tested on sandstone and carbonate rock samples. It offers large computational and memory savings when compared with algorithms based on the lattice Boltzmann method. Permeability estimates were, in general, in good agreement with laboratory measurements and numerical simulation results.

Digital rock analysis (DRA) following the digital imaging techniques can be used to image detailed rock microstructures and simulate rock properties, such as porosity and permeability, for reservoir characterization. However, for most carbonate rocks, there are apparent differences in rock texture and minerals and clear variations of rock properties with location. This kind of heterogeneity often leads to a degree of unpredictability in DRA simulation. In addition, smaller sample size is necessary for a higher resolution image but the rock properties derived from bigger physical sample are more representative. Therefore, for a heterogeneous rock sample, it is impractical to predict its rock properties with only single resolution image. In this paper, we evaluate the rock properties using two heterogeneous carbonate rock samples and their corresponding multi-scale digital rock images including thin sections, scanning electron microscope (SEM) and X-ray computed tomography (XCT) images. A DRA upscaling method is also proposed. The analysis and results show that: 1) the simulated porosity and permeability agree well with their lab measurements; 2) the heterogeneity is clearly observed with these 2D and 3D rock images and their corresponding simulations; 3) the rock properties of the two carbonate rock samples are well evaluated by these rock images, lab measurements and numerical simulations.

To determine whether erythromycin is non-inferior to metoclopramide in facilitating post-pyloric placement of self-propelled spiral nasoenteric tubes (NETs) in critically ill patients. A prospective, multicenter, open-label, parallel, and non-inferiority randomized controlled trial was conducted comparing erythromycin with metoclopramide in facilitating post-pyloric placement of spiral NETs in critically ill patients admitted to intensive care units (ICUs) of eight tertiary hospitals in China. The primary outcome was procedure success defined as post-pyloric placement (spiral NETs reached the first portion of the duodenum or beyond confirmed by abdominal radiography 24 h after tube insertion). A total of 5688 patients were admitted to the ICUs. Of these, in 355 patients there was a plan to insert a nasoenteric feeding tube, of whom 332 were randomized, with 167 patients assigned to the erythromycin group and 165 patients assigned to the metoclopramide group. The success rate of post-pyloric placement was 57.5% (96/167) in the erythromycin group, as compared with 50.3% (83/165) in the metoclopramide group (a difference of 7.2%, 95% CI − 3.5% to 17.9%), in the intention-to-treat analysis, not including the prespecified margin of − 10% for non-inferiority. The success rates of post-D1 (reaching the second portion of the duodenum or beyond), post-D2 (reaching the third portion of the duodenum or beyond), post-D3 (reaching the fourth portion of the duodenum or beyond), and proximal jejunum placement and the incidence of any adverse events were not significantly different between the groups. Erythromycin is non-inferior to metoclopramide in facilitating post-pyloric placement of spiral NETs in critically ill patients. The success rates of post-D1, post-D2, post-D3, and proximal jejunum placement were not significantly different.

The characterization of capillary transition zone (TZ), which contains large amount of oil, is challenging, because of the rock types in it affecting the fluid flow behavior. The thickness of TZ may vary from a few feet to hundreds of feet, spanning extremely low permeability and very high permeability reservoirs. Conventional core analysis (CCA) and special core analysis (SCAL) techniques can be used to study and model TZs, but the detailed pore structure information governing the rock properties rarely can be obtained. Digital rock analysis (DRA) technique can directly capture the images of rock microstructures and accurately simulate the rock properties based on digital rock images. Consequently, DRA technique can be well used for reservoir characterization. In this paper, thin sections (TS), scanning electron microscope (SEM) images, and X-Ray computed tomography (XCT) scans are used to study the rock properties for reservoir characterization. The petrography and diagenesis of TZ are also analyzed based on these digital images and simulations. DRA technique is used to simulate the rock properties. The results show that DRA can be well used to predict the rock properties such as porosity and P- and S-wave velocity. The permeability of TZ samples is found to be less than 1 mD. The TZ rock samples are qualitatively and quantitatively classified into three types such as matrix, fractured, and vuggy by an improved carbonate rock index (ICRI) method. These show that DRA is a powerful tool for carbonate reservoir characterization.

The flotation separation of smithsonite and calcite is difficult due to their similar surface physicochemical characteristics. In this study, calcium lignosulphonate (CLS) was employed as a selective inhibitor for the flotation separation of smithsonite from calcite using sodium oleate (NaOl) as collector. Flotation experiments results indicate that the calcite flotation was strongly depressed by CLS, whereas the smithsonite flotation was barely interfered. The flotation separation of smithsonite from calcite could be achieved at pH 10. A concentrate with zinc grade and recovery of 45.16% and 85.60% respectively was obtained in the artificial mixed minerals flotation experiment in the presence of CLS. The interaction mechanism was investigated by zeta potential measurement, Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) and results suggest that CLS chemically absorbed on the calcite surface in the form of Ca-SO3, which strongly hindered the successive NaOl adsorption on the calcite. However, it barely absorbed on the smithsonite surface, thus exhibiting little influence on the reaction between NaOl and smithsonite. Hence, CLS could be utilized as a selective depressant for calcite in the flotation of smithsonite.

Skarn-type ore body containing rich mineral resources, which is a type of deposit with important industrial significance and a wide distribution, is formed by metasomatism of mineral gas-bearing hydrothermal fluids on or near the contact zone between intermediate-acid-medium-basic intrusive rocks and carbonate rocks. It is hard to obtain stable data by using conventional electrical prospecting method because of strong electromagnetic interference. A new pseudo-random method is used to do geological survey work in Northeast China for interference avoidance.

At present, a large amount of oil reserves exist in underground oil reservoirs in the form of remaining oil. Therefore, to improve oil recovery, it is necessary to increase the recovery rate of remaining oil, and the well is a main area of remaining oil, so the detection of interwell reservoirs is of great significance. In view of this, this article first gives the general plan of the pseudo-random electromagnetic method for cross-well exploration, and analyzes the principle of the pseudo-random signal correlation identification technology based on the Wiener-He Fu equation; secondly, analyzes the common pseudo-random sequence Characteristics; again, based on the use of line source theory, a cross-well detection model is established, and the feasibility of the built model is verified; then the conductivity changes, buried depth changes and thickness changes of anomalous bodies are used for non-uniform wells. The influence of the electric potential distribution of the probe model; finally, the difference of each impulse response is analyzed.

The heterogeneity of a carbonate reservoir exists at all scales and always presents a challenge because it cannot be studied visually during laboratory measurements. Permeability is an important parameter and plays a key role in enhanced oil recovery operations. However, permeability anisotropy is observed at different scales of hydrocarbon production, especially in carbonate reservoirs, and complicates reservoir characterization and description. Digital rock physics (DRP) uses digitized images of reservoir rocks to compute their properties, such as porosity and directional permeability, and provide a better view of the internal structure of the rock sample, which can be used to study the heterogeneity and permeability anisotropy in carbonate rocks and reservoirs. In this study, we processed and used images of five carbonate rock samples obtained from three-dimensional (3D) computed tomography (CT) scans to calculate porosity and directional permeability. Subsamples taken at three positions along each original core plug image were processed to segmented images using image processing methods. Porosities were calculated by the voxel statistics method based on a segmented image. Absolute permeabilities of these subsamples in the three main perpendicular directions (one axial, z, and two transverse, x and y) were calculated by applying the parallel lattice Boltzmann method (PLBM) in our high-performance computing cluster (HPCC). The heterogeneity and permeability anisotropy were analyzed by combining the experimental results, the rock images, and simulated results, which included visualization of the velocity field and calculated parameter values. By analyzing these data, we found that these carbonate rock samples had strong heterogeneity and clear permeability anisotropy. In addition, we also found a close relationship between the measured values of the whole core samples and the maximum (minimum) values of the simulations for porosity (permeability). We verified that the characteristics of pore geometry, flow velocity distribution, and transport properties can be captured using DRP.

Organic-rich mudrock systems play an important role in the world's volatile petroleum industry. Due to their complex pore structures with a large portion of nano pores, the flow mechanics of gas flow in the pore space may involve nanoscale effects that could not be accounted for by classic Darcy's law. It is also very difficult to experimentally probe the transport properties of extremely low permeability rock samples. Digital rock physics (DRP) obtains a direct view of the internal structure of reservoir rock sample by digitized high resolution images to compute their properties, such as porosity and directional permeability, and hence to enable the studies of multi-scale flow mechanics in mudrocks. In this study, we present a parallel lattice Boltzmann method (PLBM) for studying nanoscale effects on a three dimensional (3D) tube flow, and then to simulate the flow process of the gas flow in real 3D pore geometry of two perpendicularly cored mudrock samples (S62H and S62V), combining with some image processing methods in DRP. The pore geometry is obtained by 3D digital image data based on ultra-high resolution X-ray computed tomography (XCT) imaging. The numerical advantages of lattice Boltzmann method (LBM) make it a powerful tool to simulate gas flow in such nano pores and estimate the absolute permeability. The new parallel implementation has been successfully performed on a powerful high performance computing cluster (HPCC) and validated with the analytical solution of a 3D tube flow model, which is taken as the elementary model for the pore networks. By simulating the nanoscale effects of rarefaction, slippage and roughness on gas flow in a nano tube model, we propose some more realistic parameters for simulating the gas flow in real mudrocks to study the flow mechanics, and to calculate the apparent directional permeability. The results show: 1) the simulated porosities (7.66% for S62H and 2.58% for S62V) are close to measured porosities (5.00% for S62H and 1.76% for S62V); 2) the estimated apparent permeability of S62H is 0.032 mD, which is close to the measured permeability of 0.02 mD; 3) the apparent directional permeability of S62V is not able to be estimated because the identified pores of subsamples are not connected in any direction with the image resolution of 65 nm/voxel; 4) the permeability anisotropy of S62H is clearly observed through the velocity field visualization and calculated permeability values; 5) the characteristics of pore geometry, flow velocity distribution and transport properties can be captured using DRP and the PLBM is an effective way to simulate complex gas flow in kerogen pores and estimate the apparent directional permeability.

The unconventional reservoirs (UCRs) play a key role in global oil and gas supply. However, their reservoir characterization is difficult because of complex pore structure and low permeability-viscosity ratio. Usually, traditional techniques hardly can be used for determination of pore structure and estimation of reservoir properties. In this case, digital rock analysis (DRA) shows the potential for capturing detailed pore structure information and simulating rock properties, such as porosity, permeability, electrical properties and elastic properties. Recently, artificial intelligence (AI) techniques have presented an ever-increasing trend in a wide variety of research and commercial fields. Many AI applications can free man from the labor of complicated works in some way. Machine leaning (ML), which is a subdivision of AI, has attracted researchers' attention and been widely used in geoscience and reservoir characterization, such as feature extracting, rock type prediction and reservoir property estimation. The incorporation of AI and DRA is becoming an inevitable development trend for future reservoir study. In this paper, firstly, DRA workflow for reservoir characterization is introduced; secondly, the commonly used ML algorithms in DRA study is reviewed; finally, a case study of characterization of a tight carbonate reservoir with ML algorithm and DRA is presented. The analysis shows that ML can be applied in any part of DRA progress such as image segmentation, feature detection, rock image classification, numerical simulation and result analysis. Compared with traditional DRA algorithm, ML-based methods can reduce manual operation that has greatly impact on the results. The combination of ML and DRA provides a new insight in UCRs characterization and outlook the future opportunities of AI to solve the oilfield problems.

Transition zone (TZ) containing a large amount of oil plays a key role in a carbonate reservoir. Its characterization is challenging because it is difficult to define top and thickness of the transition zone and it may contain many kinds of rock types differently affecting the fluid flow behavior. Routine core analysis (RCA) and special core analysis (SCAL) can be used to study for characterizaiton and modeling of TZs, but these data can rarely be used to obtain the details of the pore structure governing the rock properties. In recent years, the digital imaging technique has made great progress, because the rock microstructures can be directly imaged by using modern digital imaging technique such as thin sections (TS), scanning electron microscope (SEM) images and X-Ray computed tomography (XCT) scans. This paper focuses on the application of digital imaging technique for characterization of TZs in carbonate reservoirs located within the Middle East region. The experimental data and digital imaging data are used to study the rock samples of TZ. The results show that: 1) the rock properties of TZ samples can be accurately predicted by using digital imaging technique; 2) the petrography and diagenesis of TZ are well studied; 3) the carbonate rocks are qualitatively and quantitatively classified into three types: matrix, fractured and vuggy; 4) digital imaging technique, generally, proves to be a powerful tool for characterization of TZs in carbonate reservoirs.

Several small reservoirs and a large number of check dams had been constructed in the Wangkuai reservoir watershed after 1970s, and flood time series lacked stationarity, which affected the original design flood hydrographs for the Wangkuai reservoir. Since the location, storage capacity and drainage area of the large number of check dams were unknown, we present a method to estimate their total storage capacities (TSC) and total drainage areas (TDA) by using the recorded rainstorm and flood data. On the basis of TSC and TDA, the flood events which occurred in an undisturbed period were reconstructed under current conditions to obtain a stationary flood series. A frequency analysis was subsequently performed to assess the design flood peak and volume for both small and medium design floods with a 10–200 year return period. For large and catastrophic floods, it was assumed that the upstream check dams and small reservoirs would be destroyed, and water stored in these hydraulic structures were re-routed to the Wangkuai reservoir by unit hydrograph. The modified flood peak and volume decreased for floods with a 10–200 year return period when compared to the current design flood. But for large design floods with a return period exceeding 500 years, peak discharge increased. This study provides a new method for design flood calculation or modification of the original design flood in watersheds with a large number of check dams.

Three-dimensional (3D) information of rock microstructures is important for a better rock characterization at the micro-scale. The development of imaging technique makes this possible. For instance, in recent years, significant progress of digital rock physics (DRP) following the X-ray computed tomography (XCT) scan techniques has been made. This technique can be used to predict rock properties such as porosity, permeability, elastic moduli, and electrical conductivity. In most cases, the simulated results from rock images agree well with their lab measurements. However, some properties, such as the effective elastic moduli, strongly depend on the microstructural details of rock, which can lead to a dissatisfied comparison between numerical simulations and lab measurements. In addition, there is a clear trade-off between physical sample size and image resolution, which means that it is almost impossible to predict rock properties with single resolution image for heterogeneous carbonate rock sample. In this paper, we present a case study of rock properties evaluation using multi-scale CT images of two heterogeneous carbonate rock samples. Different image resolutions, including 40.00μm/voxel, 4.00μm/voxel, 2.00μm/voxel, 1.00μm/voxel, and 0.50μm/voxel, are used to obtain the CT images of whole core samples and their corresponding subsamples. For each resolution image of subsample, eight sub-volumes are selected to do the simulations. The rock properties including porosity, permeability and elastic properties are calculated by some effective methods such as voxel-based method (VBM), parallel lattice Boltzmann method (PLBM) and rotated staggered grid finite difference method (RSG-FDM). The results show that: 1) the simulated porosity and permeability agree well with the lab measurements; 2) the simulated P- and S-wave velocities and their lab measurements have a relatively big difference with maximum value of 62.43%; 3) the unresolved phase can reduce P- and S-wave velocities in the rocks; 4) the rock properties are well evaluated by rock images, lab measurements and numerical simulations.

Diabetic foot ulcers (DFUs) are associated with an increased risk of secondary infection and amputation. Platelet-rich fibrin (PRF), a platelet and leukocyte concentrate containing several cytokines and growth factors, is known to promote wound healing. However, the effect of PRF on diabetic wound healing has not been adequately investigated. The aim of the study was to investigate the effect of PRF on skin wound healing in a diabetic mouse model. Platelet-rich fibrin was prepared from whole blood of 8 healthy volunteers. Two symmetrical skin wounds per mouse were created on the back of 16 diabetic nude mice. One of the 2 wounds in each mouse was treated with routine dressings (control), whereas the other wound was treated with PRF in addition to routine dressings (test), each for a period of 14 days. Skin wound healing rate was calculated.Use of PRF was associated with significantly improved skin wound healing in diabetic mice. On hematoxylin and eosin and CD31 staining, a significant increase in the number of capillaries and CD31-positive cells was observed, suggesting that PRF may have promoted blood vessel formation in the skin wound. In this study, PRF seemed to accelerate skin wound healing in diabetic mouse models, probably via increased blood vessel formation.

The understanding of petrophysical properties is essential for the assessment and exploitation of hydrocarbon reserves. Reservoir rock is one of the main sources used to derive petrophysical properties by laboratory measurements. However, probing complex pore structure and heterogeneity of carbonate rocks are difficult with conventional experimental methods. Digital rock physics (DRP) is able to compute the petrophyscial parameters (e.g. porosity, permeability, elastic modulus) from three dimensional (3D) computed tomography (CT) images, which can make up for some disadvantages of traditional experiments. It also provides an understanding on how the large variations in petrophysical properties are caused by wide variations in pore type, pore shape, and pore interconnectivity.This paper is a case study on analysis of heterogeneity and estimation of petrophysical parameters in a heterogeneous rudstone sample using multi-scale CT images with three resolutions of 39.48 μm/voxel, 1.0357 μm/voxel and 65 nm/voxel. The Back-scattered Electron Image (BSEI) analysis that is used to locate subsamples in low-resolution image for high-resolution CT scan shows the range of pore-throat radius size of this sample is from 0.1μm to 10μm and most pores are under 1μm. The low-resolution images (here resolution of 39.48 μm/voxel and 1.0357 μm/voxel) show a poor pore connectivity. The high-resolution image (65 nm/voxel) provide a more detailed pore structure that contributes to estimation of petrophysical properties. The estimated porosity (21.92%) and absolute permeability (6.54mD) from the high-resolution images are close to the lab measurements (22.7% and 4.9mD), which shows the accuracy of DRP in this particular sample. The relative errors of elastic modulus between the simulation and the measurements are 77.23% and 87.68% for bulk moduli and shear moduli, respectively. The image registration locates the Nano-CT images in the low-resolution image (1.0357 μm/voxel), which better characterize the pore geometry in different 3D image and provide a new way to do the upscaling work. The multi-scale images, the visualization of fluid velocity distribution, the lab measurements, and the simulated values show the heterogeneity of this carbonate sample.

Full-thickness skin defects represent a significant and urgent clinical problem. Dermal substitutes serving as a regenerative template to induce dermal reconstruction provide a promising method to treat serious skin defects. Although collagen-chitosan dermal scaffolds display good biocompatibility and a suitable porous structure for angiogenesis and tissue regeneration, their poor mechanical properties compromise their application. To develop a well-supported dermal substitute, a poly(l-lactide-co-glycolide) (PLGA) knitted mesh was fabricated and integrated with collagen-chitosan scaffold (CCS) to obtain a PLGA knitted mesh-reinforced CCS (PLGAm/CCS). The morphology of this PLGAm/CCS was investigated in vitro. To characterize the tissue response, specifically angiogenesis and tissue regeneration, the PLGAm/CCS was transplanted in combination with thin split-thickness autografts to repair full-thickness skin wounds using a one-step surgical procedure in Sprague-Dawley rats. These results were then compared with CCSs. At weeks 2, 4 and 8 after the operation, the healing wounds were imaged to analyse wound changes, and tissue specimens were harvested for histology, immunohistochemistry, real-time quantitative polymerase chain reaction and Western blot analysis. The results demonstrated that collagen-chitosan sponge in the PLGAm/CCS remained porous, interconnected and occupied the openings of PLGA mesh, and the incorporation of the PLGA knitted mesh into CCS improved the mechanical strength with little influence on its mean pore size and porosity. Following transplantation, PLGAm/CCS inhibited wound contraction, and effectively promoted neotissue formation and blood vessel ingrowth. In conclusion, the mechanical strength of the scaffolds plays an important role in the process of tissue regeneration and vascularization. The ability of PLGAm/CCS to promote angiogenesis and induce in situ tissue regeneration demonstrates its potential in skin tissue engineering.

Human facial aesthetics relies on the classification of facial features and standards of attractiveness. However, there are no widely accepted quantitative criteria for facial attractiveness, particularly for Chinese Han faces. Establishing quantitative standards of attractiveness for facial landmarks within facial types is important for planning outcomes in cosmetic plastic surgery. The aim of this study was to determine quantitatively the criteria for attractiveness of eight female Chinese Han facial types. A photographic database of young Chinese Han women’s faces was created. Photographed faces (450) were classified based on eight established types and scored for attractiveness. Measurements taken at seven standard facial landmarks and their relative proportions were analyzed for correlations to attractiveness scores. Attractive faces of each type were averaged via an image-morphing algorithm to generate synthetic facial types. Results were compared with the neoclassical ideal and data for Caucasians. Morphological proportions corresponding to the highest attractiveness scores for Chinese Han women differed from the neoclassical ideal. In our population of young, normal, healthy Han women, high attractiveness ratings were given to those with greater temporal width and pogonion–gonion distance, and smaller bizygomatic and bigonial widths. As attractiveness scores increased, the ratio of the temporal to bizygomatic widths increased, and the ratio of the distance between the pogonion and gonion to the bizygomatic width also increased slightly. Among the facial types, the oval and inverted triangular were the most attractive. The neoclassical ideal of attractiveness does not apply to Han faces. However, the proportion of faces considered attractive in this population was similar to that of Caucasian populations. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Mechanical properties are essential considerations for the design of porous scaffolds in the field of tissue engineering. To develop a well-supported hybrid dermal substitute, poly( l -lactide-co-glycolide) (PLGA) yarns were knitted into a mesh with relative fixed loops, followed by incorporation into collagen–chitosan scaffolds (CCS) to obtain PLGA knitted mesh-reinforced CCS (PLGAm/CCS). The morphology and tensile strength in both the dry and wet state of PLGAm/CCS were investigated in vitro . To characterize the tissue response, specifically angiogenesis and tissue regeneration, PLGAm/CCS was embedded subcutaneously in Sprague–Dawley rats and compared with two control implants, i.e. , PLGA mesh (PLGAm) and CCS. At weeks 1, 2, and 4 post surgery, tissue specimens were harvested for histology, immunohistochemistry, real-time quantitative PCR and Western blot analysis. These results demonstrated that the incorporation of PLGA knitted mesh into CCS can improve the mechanical strength with little influence on its mean pore size and porosity. After implantation, PLGAm/CCS can resist contraction and promote cell infiltration, neotissue formation, and blood vessel ingrowth, effectively. In conclusion, the mechanical strength of scaffolds can play a synergetic role in tissue regeneration and vascularization by maintaining its 3D microstructure. The ability of PLGAm/CCS to promote angiogenesis and induce in situ tissue formation demonstrates its strong potential in the field of skin tissue engineering.

Carbonate reservoirs can be extremely complex when estimating oil and gas production due to their texture heterogeneity, mainly from the structure of the pore space. Understanding the flow mechanism in carbonate reservoirs is essential for successful hydrocarbon development and production. Permeability is an important parameter and plays a key role in enhancing production and recovery. However, usually permeability anisotropy is observed due to the deposition, diagenesis, and/or tectonic movements of the rock formations, which complicates the reservoir characterization and description. The digital rock physics (DRP) following the computed tomography (CT) scan techniques has progressed at a rapid speed since the three dimensional (3D) pore geometry structure of reservoir rocks can be captured and visualized and it is able to compute core sample parameters (such as porosity and absolute permeability) from the digital image (Kalam et al. 2013). To better understand permeability anisotropy in core samples from a carbonate reservoir, some accurate methods in DRP are followed. In this study, five digital rock samples were selected to do the simulation. For each digital rock sample, in order to reduce the computational cost, three cubic subsamples were selected respectively from the upper, middle, and lower part of whole core plug as digital rock models. Then, the porosity and the absolute permeabilities in three perpendicular directions were computed (one in the axial direction, z, and two, x and y, perpendicular to the axis) in each of these cubic subsamples using the parallel lattice Boltzmann method (PLBM) in the high-performance-computing-cluster (HPCC). The results show that: (1) All the calculated porosities of the subsamples are close to the experimental porosities; (2) the calculated permeabilities in z direction of representative subsamples (Kz) are all close to the experimental permeabilities in the axial direction; (3) for four samples, Kz is much higher than the permeabilities in x and y directions (Kx and Ky, respectively). In other words, both Kz/Ky and Kz/Kx are higher than 1, and Kx/Ky ratios are closer to 1; (4) for only one sample, both Kz/Kx and Kz/Ky are less than 1, which may be caused by some geological structures present in this sample (stylolite); (5) permeability anisotropy in these carbonate samples is clearly confirmed and quantified.

A novel dermal substitute of combining recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) with a porous heparinized collagen/chitosan scaffolds was developed, considering the inadequate angiogenesis during repair of full-thickness skin defects. The physicochemical properties of heparinized collagen/chitosan scaffolds were examined and in vitro release pattern of rhGM-CSF from scaffolds was measured by ELISA. Four groups of composite scaffolds (heparinized or unheparinized scaffolds loaded with or without rhGM-CSF) were fabricated for subcutaneous implantation in young adult male Sprague-Dawley (SD) rats. Tissue specimens were harvested at different time points after implantation for histopathological, immunohistochemical observation, and Western blotting analysis. The heparinized scaffolds (H1E) showed slower biodegradation and sustained release of rhGM-CSF in vitro, although no significantly different release pattern was observed between the H1E and unheparinized scaffolds (H0E). In vivo investigation revealed that the heparinized scaffolds loaded with rhGM-CSF (H1E/rhGM-CSF) had the best cellular adhesion and migration, new vessel formation, and highest expression of VEGF and TGF-β1, indicating promoted angiogenesis. This study demonstrated that composite dermal substitute of combining rhGM-CSF with a porous heparinized collagen/chitosan scaffolds could be a potential therapeutic agent for full-thickness skin defects because of its sustained delivery of rhGM-CSF. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.

Thermo-, pH-, and electrochemical-sensitive cellulose graft copolymers, hydroxypropyl cellulose-g-poly(4-vinylpyridine)-Os(bipyridine) (HPC-g-P4VP-Os(bpy)), were synthesized and characterized. The electrochemical properties of the resulting material were investigated via cyclic voltammetry by coating the graft copolymers on the platinized carbon electrode. The results indicated that the electrochemical properties of the graft copolymer modified electrode were responsive to the pH values of the electrolyte solution. The reversible transformation between the active and inactive state originated from the changes in the architecture of the HPC-g-P4VP-Os(bpy) graft copolymer at different pH values. At high pH (e.g., above the pK(a) of P4VP), the chains of P4VP collapsed, and the electrochemical activity of the electrode was reduced. With immobilization of glucose oxidase (GOx) on the graft copolymer decorated electrode, a biosensor for glucose detection was prepared. The current of the biosensor depended on the glucose concentration in the detected solution and increased with the successive addition of glucose.

Knitting is an ancient and yet, a fresh technique. It has a history of no less than 1,000 years. The development of tissue engineering and regenerative medicine provides a new role for knitting. Several meshes knitted from synthetic or biological materials have been designed and applied, either alone, to strengthen materials for the patching of soft tissues, or in combination with other kinds of biomaterials, such as collagen and fibroin, to repair or replace damaged tissues/organs. In the latter case, studies have demonstrated that knitted mesh scaffolds (KMSs) possess excellent mechanical properties and can promote more effective tissue repair, ligament/tendon/cartilage regeneration, pipe-like-organ reconstruction, etc. In the process of tissue regeneration induced by scaffolds, an important synergic relationship emerges between the three-dimensional microstructure and the mechanical properties of scaffolds. This paper presents a comprehensive overview of the status and future prospects of knitted meshes and its KMSs for tissue engineering and regenerative medicine.

The 2012 C-NCAP added the evaluation of the potential risks of injury of female occupant in the rear seats. A female dummy will be used in the C-NCAP test. The frontal impact model of the female dummy in the rear seats was established by MADYMO. Four different vehicles were analyzed respectively in the two conditions that whether the secondary crash occurred or not. And the effect of the three factors which included the vehicle acceleration, rear space and seatbelt on the female dummy injury was summarized. Experimental results showed that with the peak acceleration smaller and the rebound time later, the values of dummy injury on the head and neck would be smaller under the premise of the same vehicle, and appropriate seat belts load limiter could reduce the dummy injury.

This is a work aimed to investigate the biodegradability, biocompatibility and mechanical property of the poly-lactide-co-glycolic acid (PLGA) knitted mesh preliminarily and to further explore its applications in tissue engineering and regenerative medicine. The biological property of PLGA mesh was investigated comprehensively with the degradation experiment in vitro, the acute cytotoxicity assay, the intradermal irritation test and the subcutaneous implantation test in vivo utilized. The degradation experiment in vitro demonstrated that the pH value of the removed solution fluctuated between 6.68 and 7.33. The elastic modulus of the PLGA mesh increased at first and then decreased afterwards. The acute toxicity test and the intradermal irritation test indicated that the PLGA mesh was with innocuity safety. The PLGA mesh accelerated degradation and was replaced gradually by the neotissue. The results of immunohistochemical staining demonstrated that the number of ED-1+ cells increased at first and then decreased afterwards. The PLGA mesh with excellent mechanical properties, good biocompatibility and favorable degradation ratio has the potential to be employed as a "skeleton" to reinforce the mechanical property of collagen-based dermal substitutes in tissue engineering.

Re-epithelialization is the first and most important step in cutaneous wound healing. The vital role of epidermal cells, or keratinocytes, in accelerating wound healing has long been established. The technique of delivering the cultured and uncultured epidermal cells to the wound bed takes a variety of forms including cultured epithelial autografts (CEAs), tissue-engineered skin equivalent, epidermal suspension and microbead-loaded composite. These techniques, together with the keratinocyte culturing method and scaling up equipment, are still the ongoing research. Application of these techniques also bears direct impact on the outcome of the wounded patients. Best understanding of the delivery technique and its relationship with the culturing method and delivery vehicle could benefit not only the wounded patient but also the development of tissue-engineered skin equivalent.

The process of wound healing involves a complex interplay of cells, mediators, growth factors and cytokines. GM-CSF has been shown to be involved in a number of processes essential in this event. Topically applied rhGM-CSF has been reported to successfully treat wounds with diverse etiology, including burns, chronic venous leg ulcers, pressure ulcers, and leprosy ulcers, both in animal experiments and clinical studies. To evaluate the effect of the rhGM-CSF on wound healing, 8 RCT studies and 23 clinical studies and case reports are collected for analysis of the evidence. The overall effects of rhGM-CSF on the healing of wound are diverse. Topically applied rhGM-CSF is beneficial for deep partial-thickness burn wounds, chronic leg ulcers, and leprosy ulcers. rhGM-CSF may have a positive effect on other type of chronic ulcers such as pressure ulcers and cancer related ulcers, but the evidence is not sufficient for generalised use at present. rhGM-CSF is suggested have no accelerating effect on the healing of healthy wounds or surgical incisions.