Preparation of poly(ether‐block‐amide)/poly(amide‐co‐poly(propylene glycol)) random copolymer blend membranes for CO2/N2 separation

A series of poly(amide‐co‐poly(propylene glycol)) (PA‐PPG) random copolymers with different content of PPG were designed by polycondensation reaction. These random copolymers were blended up to 60% with commercially available Pebax 2533. The blend membranes were characterized by Fourier‐transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), scanning electron microscope (SEM). Gas permeation properties of these blend membranes were investigated using five single‐gases (CO₂, H₂, O₂, CH₄, and N₂) at different temperature of 25–55°C and 1.0 atm. The impacts of content of PA‐PPG with different PPG content and operating temperature on CO₂ separation properties of Pebax/PA‐PPG blend membranes were studied. The results showed that CO₂ permeability gradually increased with the increasing operating temperature, whereas CO₂ permeability gradually decreased with the increase in content of PA‐PPG. CO₂/N₂ selectivity gradually increased with the increase in content of PA‐PPG. In particular, Pebax/PA‐PPG (50)–60% displayed excellent CO₂ and O₂ separation properties (P_CO2 = 79.7 Barrer and P_O2 = 13.6 Barrer, CO₂/N₂ = 34.7 and O₂/N₂ = 5.9) at 25°C and 1.0 atm. POLYM. ENG. SCI., 59:E14–E23, 2019. © 2018 Society of Plastics Engineers     

柠条对滩羊肉品质、胃肠道挥发性脂肪酸及其菌群的影响

为探索日粮中添加柠条影响瘤胃、结肠内微生物生成的挥发性脂肪酸水平,进而调节滩羊肉品质、脂肪组织中主要脂肪酸含量的作用,本研究选取12只四月龄滩羊母羔随机分为两组,NC组饲喂30%精料及70%苜蓿颗粒,CK组为10%柠条替代等量苜蓿。预饲期10 d,正试期60 d。饲喂期结束屠宰时取其背最长肌、股四头肌、皮下脂肪,瘤胃、结肠内容物,利用16S rRNA测序技术、气相色谱-质谱联用技术等对滩羊瘤胃、结肠内菌群、脂肪组织的脂肪酸含量及肌肉理化特性进行测定。结果表明,饲喂柠条可导致滩羊股四头肌的压榨损失有提高的趋势,系水力和熟肉率有所下降;但饱和脂肪酸有降低的趋势,不饱和脂肪酸有提高的趋势;皮下脂肪中的软脂酸含量显著降低(P<0.05);瘤胃内丁酸和结肠内乙酸的浓度显著降低(P<0.05),结肠内异丁酸和异戊酸等支链脂肪酸水平极显著提高(P<0.01)。斯皮尔曼相关性分析显示,瘤胃内5-7N15菌属和YRC22菌属均与丁酸含量趋向正相关,而结肠内密螺旋体属与乙酸含量趋向正相关,但与异丁酸含量趋向负相关(0.05相似文献   

富硒平菇粉的抗癌活性评价及富硒代糖面包的研制

该研究采用不同总硒浓度的富硒平菇粉联合5-FU处理肝癌细胞HepG2,应用CCK-8法、流式细胞术双染法探讨富硒平菇粉联合5-FU的抑癌效果,并以富硒平菇粉为原料研制一款富硒代糖面包,为富硒功能食品研发提供参考依据。结果表明,富硒平菇粉对肝癌细胞HepG2增殖有抑制作用,抑制率范围为13.89%~27.39%;不同总硒浓度的富硒平菇粉联合5-FU干预HepG2肝癌细胞36 h后,凋亡细胞数量呈硒作用浓度依赖性增高（p<0.05）;总凋亡率分别是26.36%~49.72%,且凋亡率高于5-FU组（p<0.05)。富硒代糖面包的最佳加工工艺配方为：200 g面粉中富硒平菇粉添加量为0.06 g,复配代糖添加量为25 g,烘烤温度为上下火175 ℃,烘烤时间为20 min,总硒含量为（0.17±0.01）mg/kg。综上所述,采用不同总硒浓度的富硒平菇粉联合5-FU处理肝癌细胞HepG2,发现富硒平菇粉联合5-FU可抑制HepG2肝癌细胞生长,起到增效解毒的作用,并成功研制出富硒代糖面包的最佳工艺,具有较好的研究和应用价值。     

Preparation of magnetic zeolite/chitosan composite using silane as modifier for adsorption of Cr(VI) from aqueous solutions

This study aimed to prepare an efficient, cost-effective, and separable magnetic zeolite/chitosan composite (MZFA/CS) adsorbent from solid waste to deal with the water pollution of Cr(VI). The MZFA/CS was characterized by X-ray fluorescence (XRF), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and vibrating sample magnetometer (VSM) techniques. Then, the effect of pH, temperature, initial concentration of Cr(VI) ions, and contact time was considered in the study. For a sorbent dose of 0.1 g in 50 mL of a Cr(VI) solution, at a contact time of 30 min, temperature of 30°C, and a pH of 3, an adsorption capacity (q_e) of 16.96 mg g⁻¹ was achieved. Adsorption kinetics and isotherm data obtained for all adsorption systems were well-fitted by pseudo-second-order and Langmuir models, respectively. The thermodynamic study suggested that the adsorption process is spontaneous and endothermic in nature. In summary, the adsorbent with better separability (Ms = 16.83 emu g⁻¹) and adsorbability was successfully fabricated.     

A comprehensive review of computer-aided whole-slide image analysis: from datasets to feature extraction,segmentation, classification and detection approaches

With the development of Computer-aided Diagnosis (CAD) and image scanning techniques, Whole-slide Image (WSI) scanners are widely used in the field of pathological diagnosis. Therefore, WSI analysis has become the key to modern digital histopathology. Since 2004, WSI has been used widely in CAD. Since machine vision methods are usually based on semi-automatic or fully automatic computer algorithms, they are highly efficient and labor-saving. The combination of WSI and CAD technologies for segmentation, classification, and detection helps histopathologists to obtain more stable and quantitative results with minimum labor costs and improved diagnosis objectivity. This paper reviews the methods of WSI analysis based on machine learning. Firstly, the development status of WSI and CAD methods are introduced. Secondly, we discuss publicly available WSI datasets and evaluation metrics for segmentation, classification, and detection tasks. Then, the latest development of machine learning techniques in WSI segmentation, classification, and detection are reviewed. Finally, the existing methods are studied, and the application prospects of the methods in this field are forecasted.

     

Efficiency evaluation of healthcare services in China based on stochastic multicriteria acceptability analysis and directional distance function

Evaluating the efficiency of healthcare services accurately can help in analyzing the rationality of inputs and outputs in such services. Considering the consistency and equity of assessment criteria, this study conducts the stochastic multicriteria acceptability analysis (SMAA-2) with a directional distance function to evaluate the efficiency of healthcare services in 31 provincial administrative regions of mainland China, as observed in 2018. We use SMAA-DDF to explore all the projection directions to the efficient frontier instead of a certain projection direction. We measure the maximum and average efficiencies for each of the 31 provincial healthcare services. Our empirical findings show that only seven provinces achieve optimal healthcare service efficiency; the eastern area performed the best, followed by the central, western, and northeast areas. Furthermore, the path along the projection directions is provided to help inefficient provinces improve their efficiency and obtain the best possible positions.     

Engineering Bioactive M2 Macrophage-Polarized Anti-Inflammatory,Antioxidant, and Antibacterial Scaffolds for Rapid Angiogenesis and Diabetic Wound Repair

Diabetic wound healing still faces great challenges due to the excessive inflammation, easy infection, and impaired angiogenesis in wound beds. The immunoregulation of macrophages polarization toward M2 phenotype that facilitates the transition from inflammation to proliferation phase has been proved to be an effective way to improve diabetic wound healing. Herein, an M2 phenotype-enabled anti-inflammatory, antioxidant, and antibacterial conductive hydrogel scaffolds (GDFE) for producing rapid angiogenesis and diabetic wound repair are reported. The GDFE scaffolds are fabricated facilely through the dynamic crosslinking between polypeptide and polydopamine and graphene oxide. The GDFE scaffolds possess thermosensitivity, self-healing behavior, injectability, broad-spectrum antibacterial activity, antioxidant and anti-inflammatory ability, and electronic conductivity. GDFE effectively activates the polarization of macrophages toward M2 phenotype and significantly promotes the proliferation of dermal fibroblasts, the migration, and in vitro angiogenesis of endothelial cells through paracrine mechanisms. The in vivo results from a full-thickness diabetic wound model demonstrate that GDFE can rapidly promote the diabetic wound repair and skin regeneration, through fast anti-inflammation and angiogenesis and M2 macrophage polarization. This study provides highly efficient strategy for treating diabetic wound repair through designing the M2 polarization-enabled anti-inflammatory, antioxidant, and antibacterial bioactive materials.     

耐压管装配尺寸链的研究

通过对耐压管装配尺寸链的计算,得出了耐压管装配时轴向尺寸控制的方法。     

Upgraded multipulse laser and multipoint Thomson scattering diagnostics on EAST

Recently a new Thomson scattering diagnostic system was upgraded in EAST tokamak experiment using a multipulse Nd:YAG (neodymium-yttrium aluminium garnet) laser and a multipoint observation volumes. This diagnostic uses a new optical laser alignment technique that was made to determine accurately the laser position, and a new lens collection system that enables the measurement of wider plasma's object. A composite control system made we can get the results in several seconds. Furthermore, a new data processing method was adopted for much exact results.