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In this paper, the interpolation sub-pixel mapping (ISM) based on multiple sub-pixel shifted images (MSSIs) based on a consideration of the point spread function (PSF) effect, named as MSSI-PSF, is...

The inner and surface morphology of the polyphenylene sulfide membrane could be well optimized by controlling the phase separation during the thermally induced phase separation process.

Objective: To analyze the status and differences of health resources allocation in undeveloped areas of Chongqing, China, and to provide empirical evidence for health planning and further optimization of health resources allocation. Methods: The comprehensive evaluation system for health resources allocation in underdeveloped areas was constructed. Afterwards, the entropy weight TOPSIS method was used to comprehensively evaluate the level of health resources allocation in 22 underdeveloped areas of Chongqing, and the K-means cluster analysis method was used to classify the comprehensive evaluation results. Results: The level of health resources allocation in Chongqing’s underdeveloped areas was relatively low and the regional differences were significant. The level of health resources allocation in 22 underdeveloped areas can be divided into 4 categories, of which Shizhu, Nanchuan, Qianjiang, and Liangping were better, Wuxi, Hechuan, Tongnan, and Youyang were poorer. Conclusion: It is recommended to increase the differentiation and pertinence of health policies in undeveloped areas, to achieve dynamic management and control of health resources, to promote the sustainable development of human resources for health, and to ensure that the level of health financing is improved.

The effects of ozone aging on the structure and related properties of poly(hexamethylene adipamide) (PA66), poly(p-phenylene dodecanediamine) (PA12T), poly(m-phenylene isophthalamide) (PMIA), and p...

Poly(vinylidene fluoride) (PVDF)-electrosprayed nanofibers have been the subject of much research due to their flexibility and piezoelectric properties compared to other piezoelectrics, for example, ceramics or other polymeric materials. The piezoelectric performance of PVDF is mainly related to the presence of β-phase. This study aims to determine the influence of working and formulation parameters on the generation of β-phase, morphology, and crystal structure of PVDF nanofibers. In addition, this research innovatively analyzes the effect of the dispersion state of PVDF molecular chains in the solvent on the electrospinning results. The morphology and crystal structure of PVDF nanofibers were determined using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). Beadless nanofibers are obtained when the PVDF concentration reaches the semi-diluted regime entangled in dimethylformamide (DMF) or DMF/acetone solution. The optimization of the process parameters (static collector, tip to collector distance—25 cm, flow rate—1 mL/h, applied voltage—20 kV) allows the increase in the β-phase fraction from 68.3% ± 1.2% to 94.5% ± 0.6% for a PVDF concentration of 25 w/v% in a DMF/acetone mixture (2/3 v/v). With these same parameters applied to a rotating collector, it was observed that the piezoelectric performance is at maximum for a maximum β-phase fraction of 90.6% ± 1.1%, obtained for a rotational speed of 200 rpm. The effect of orientation of PVDF nanofibers on piezoelectric properties was quantitatively discussed for the first time; the piezoelectric properties are independent of the alignment of the nanofibers.

Polyvinylidene fluoride (PVDF) is among the most attractive piezo-polymers due to its excellent piezoelectricity, lightweight, flexibility, high thermal stability, and chemical resistance. PVDF can exist under different forms of films, membranes, and (nano)fibers, and its piezoelectric property related to its β phase content makes it interesting for energy harvesters and wearable applications. Research investigation shows that PVDF in the form of nanofibers prepared by electrospinning has more flexibility and better air permeability, which make them more suitable for these types of applications. Electrospinning is an efficient technique that produces PVDF nanofibers with a high β phase fraction and crystallinity by aligning molecular dipoles (–CH2 and –CF2) along an applied voltage direction. Different nanofibers production techniques and more precisely the electrospinning method for producing PVDF nanofibers with optimal electrospinning parameters are the key focuses of this paper. This review article highlights recent studies to summarize the influence of electrospinning parameters such as process (voltage, distance, flow rate, and collector), solution (Mw, concentration, and solvent), and ambient (humidity and temperature) parameters to enhance the piezoelectric properties of PVDF nanofibers. In addition, recent development regarding the effect of adding nanoparticles in the structure of nanofibers on the improvement of the β phase is reviewed. Finally, different methods of measuring piezoelectric properties of PVDF nanofibrous membrane are discussed.

The objective of the present study was to evaluate the 2-year effectiveness of modified Shenzhuo formula in the treatment of overt proteinuria diabetic kidney disease (DKD). Patients diagnosed with type 2 DKD in the clinical research database of Prof Xiaolin Tong (>20,000 data points) with >1-year follow-up were screened for this study. Patients’ demographic data, chief complaint, present illness, past history, allergic history, personal history, family history, test results, tongue images, pulse information, and prescription information at 1, 1.5, and 2 years of follow-up were analyzed. EpiData3.1 was used to establish the electronic database of this research and SPSS v20.0 (SPSS Inc, Chicago, IL) was used for performing statistical analyses. The patients’ common main symptoms of overt proteinuria DKD were weak breath and fatigue, numbness of limbs, insomnia, blurred vision, nocturia, edema, low backache, constipation, itchy skin ulcer, and chills. The average 24-hour urinary protein of patients treated with modified Shenzhuo formula was statistically significantly lower than baseline values at 1, 1.5, and 2 years (0.66 g, 95% confidence interval [CI] [−0.95, −0.41]; 1.00 g, 95% CI [−1.67, 0.38]; 1.11 g, 95% CI [−1.79, −0.57]). There are no statistically significant differences between the glomerular filtration rate at the baseline and that after modified Shenzhuo formula intervention. Statistically significant reductions in serum triglyceride and glycosylated hemoglobin values and systolic blood pressure also were recorded. Other indexes, including serum creatinine, blood urea nitrogen, diastolic blood pressure, cholesterol, high-density lipoprotein, and low-density lipoproteins, did not differ between baseline and post-treatment time points. Modified Shenzhuo formula could reduce 24-hour urinary protein excretion in patients with DKD. The formula maybe had the potential advantages on glomerular filtration rate, creatinine reciprocal, blood lipid levels, etc.

Objective: To describe the current situation of health records establishment of residents in main urban areas of Chongqing, analyze its influencing factors and provide reference suggestions to promote the establishment of residents' health records, so as to narrow the gap between China and other countries. Methods: A self-designed questionnaire survey was conducted among 900 residents who had lived in nine districts of Chongqing for more than 6 months by stratified random sampling. Results: In 2018, 61.4% of the sample population in the main urban area of Chongqing had health records, while 20% didn't have health records and 18.5% were unclear about whether they had health records or not; Differences in gender, age, educational background, occupation, household registration, housing type were statistically significant for the establishment of health records (P < 0.05); Polytomous logistic regression analysis showed that gender, age, educational background, occupation, household registration were the influencing factors of the establishment of health records. Conclusion: The rate of residents in the main urban areas of Chongqing who have health records needs to be improved. It is hard to establish health records for male, low-educated and floating population. Therefore, the third-party organizations and media should play a role in promoting the establishment of health records for such populations under the leadership of government departments, in order to make contributions to narrowing the gap between China and other countries.

Poly(ether ether ketone) (PEEK) hollow fiber membranes were successfully prepared from miscible blends of PEEK and polyetherimide (PEI) via thermally-induced phase separation (TIPS) with subsequent extraction of the PEI diluent. The phase structure evolution, extraction kinetics, membrane morphology, pore size distribution and permeability for the hollow fiber membrane were studied in detail. Extraction experiments, differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMA) studies showed that the heat treatment had a significant influence on the two-phase structure of PEEK/PEI, and that it was controlled by the crystallization kinetic of PEEK and the diffusion kinetic of PEI. As the annealing temperature increased, the controlling factor of the phase separation changed from PEEK crystallization to PEI diffusion, and the main distribution of the amorphous PEI chains were changed from the interlamellar region to the interfibrillar or interspherulitic regions of PEEK crystallization. When the annealing temperature increased from 240 &deg, C to 280 &deg, C, the extracted amount of PEI increased from 85.19 to 96.24 wt %, and the pore diameter of PEEK membrane increased from 10.59 to 37.85 nm, while the surface area of the PEEK membrane decreased from 111.9 to 83.69 m2/g. Moreover, the water flux of the PEEK hollow fiber membranes increased from 1.91 &times, 10&minus, 2 to 1.65 &times, 1 L h&minus, 1 m&minus, 2 bar&minus, 1 as the annealing temperature increased from 240 &deg, C to 270 &deg, C. The structure and properties of the PEEK hollow fiber membrane can be effectively controlled by regulating heat treatment conditions.