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Background: Caveolin-1 (CAV1) is an essential structural component of caveolae, regulates cellular processes through complex cellular signaling pathways, and influences tumorigenicity. However, the role of the CAV1 (rs7804372) polymorphism in digestive cancers remains inconclusive. The meta-analysis was performed to evaluate the effect of CAV1 polymorphism on digestive cancer susceptibility and to provide a basis for precise treatment. Methods: The databases of PubMed, EMBASE, Google Scholar and CNKI were used to retrieve the published studies on CAV1 (rs7804372) polymorphism and susceptibility to digestive cancers up to June 2020. Two researchers conducted study screening, data extraction, and methodological quality evaluation separately according to inclusion and exclusion criteria. Review Manager 5.3 software was used to conduct the meta-analysis. Results: Six case-control studies were enrolled, including 2477 patients with digestive cancers and 2477 healthy controls. The pooled results showed that the CAV1 rs7804372 (T29107A) polymorphism increased the risk of digestive cancer occurrence in the allele (T vs. A: odds ratio (OR) 1.33, 95% confidence interval (CI): 1.15–1.53, P

Mechanochemical activation-assisted synthesis, compared to conventional wet methods, exhibits advantages such as higher chemical homogeneity and better quality of the resulting nano-crystals, in preparing nano-sized aluminum hydride (AlH3). Solid/liquid state milling is effective and convenient for production of α-AlH3/LiCl nano-composites through a mechanochemical reaction of LiH and AlCl3 in [2-Eim] OAc. However, the kinetics of this process has not been thoroughly studied. In this work, we studied the kinetics of mechanochemical synthesis of α-AlH3/LiCl nano-composite to understand the reaction process and find the optimum milling parameters (including shortest time to achieve high-quality product). We performed isothermal desorption tests for as-milled samples at 80 °C. Structures of the products were analyzed using X-ray powder diffraction. Johnson-Mehl-Avrami (JMA) model was adopted to describe the process, which contains transformation fraction and chemical reaction controlled regime. Kinetics of mechanochemical reaction at the beginning was limited by diffusion rate of the reagent, and later controlled by nucleation of AlH3. By fitting the experimental data, apparent activation energy for the mechanochemical reaction was calculated as 39.6 kJ/mol.

With switching power supply being widely used in Smart Meter, there exists more restrictions on the performance of it. This paper designs a single-ended flyback switching power supply based on LNK364DN chips which is used in intelligent single-phase table, Compares the advantages and disadvantages of the switching power supply and the traditional linear regulated power supply, and introduces the reaction type switching power supply design principle and working process. In order to satisfy the security requirements, this paper also designs the EMI suppression circuit, surge suppression current, clamp circuit, etc. The design process, including the maximum duty cycle including transformer, the primary inductance calculation, etc, of the flyback type switch power supply transformer is introduced in detail. The experimental results show that the switch regulated power supply has small volume, good electromagnetic compatibility, small ripple, low power consumption, high efficiency of AC/DC transform and excellent performance .

Poly(aspartic acid-lysine) copolymers (PAL), as an alternative product to traditional water treatment agents, was developed based on poly(aspartic acid) through microwave-assisted synthesis of aspartic acid and lysine. Its biocompatibility and performance in inhibiting scale and corrosion are determining factors in its application. In this paper, biodegradability of PAL was investigated by carbon dioxide evolution tests. The degradation ratio of PAL on day 10 and day 28 respectively reached 35.01% and 80.00%, which indicated that PAL was a degradable water treatment agent. PAL is superior to polyacrylic acid and phosphonic carboxylic acid in biodegradability. With the increase in the addition ratio of lysine in copolymerization process and the decrease in the molecular weight of copolymer, the biodegradability of PAL was significantly enhanced. In addition, the incubation period before the biodegradation was shortened. The result showed that Cu 2+ could decrease the degradation rate through inhibiting enzymatic activities.

Background: Endurance exercise improves lipid and lipoproteins levels, while low high-density lipoprotein cholesterol (HDL-C) levels are risk factors for cardiovascular disease. There is a lack of evidence for the exercise characteristics in increasing lipids level, irrespective of the fact that endurance exercise increases lipids and lipoproteins level. The aim of this study was to clarify the effect and characteristics of endurance exercise in increasing HDL-C in randomized controlled trials. Methods: A search was performed for published studies between 1999 and 2014. Studies that assessed endurance exercise for ≥8 weeks and also reported the HDL-C levels pre- and post-training were included. The random effects model was used to measure the association between exercise and net change of HDL-C. Univariate regression analyses investigated the correlation of exercise characteristics. Subgroup and sensitivity analyses were performed to explore the sources of heterogeneity and the effect of potential confounders. The influence of pre-exercise lipid profile was assessed by meta-regression. Data were analyzed using Stata SE (12.0). Results: Fourteen studies with a total of 777 subjects were included. The mean HDL-C was reported to be increased and was statistically significant (weighted mean difference: 4.41 mg/dL; 95% confidence interval [CI]: 2.16–6.66 mg/dL, P < 0.001; I2 = 87.4%, P < 0.001). Univariate analysis indicated that exercise length was significantly associated with a net change of HDL-C (r = 0.56, P = 0.01). Nevertheless, there was no significant association between exercise frequency, duration, and total minutes. By subgroup analysis, exercise increased HDL-C level in Asia, Europe, and Africa and among all body mass index groups (P < 0.05). None of the studies omitted, in turn, seemed to substantially influence the effect of exercise on HDL-C by sensitivity analysis. Meta-regression showed that pre-exercise total cholesterol (TC) negatively correlated with net change of HDL-C (95% CI: 0.127, −0.018, r = −0073, P = 0.012). However, pre-exercise triglycerides, low-density lipoprotein cholesterol, and HDL-C did not correlate with a net change of HDL-C. Conclusions: Regular endurance exercise increases HDL-C level in any weight population. Exercise length of more than 8 weeks was the most important element of an exercise prescription. Among all lipid profiles, only the initial lower TC level responded better to exercise training and was more effective in increasing HDL-C level.

采用简单的热扩散法, MoO3可在模板纳米孔道内有序生长, 经还原后获得MoO2和金属Mo纳米管／线阵列. 运用XRD、SEM、TEM、HRTEM等技术对产物进行了表征. 结果表明: 在70 nm孔径的阳极氧化铝模板上, H2/N2气氛下600 ℃时的还原产物为单晶MoO2; 而在50 nm的模板上, 同样条件的还原产物为MoO2微晶聚合体. 乙醇的加入能够大大改善产物的形貌. H2气氛, 650 ℃以上温度下进一步还原得到了金属Mo纳米管阵列.

Corrosion and plugging caused by sulfate reducting bacteria, total growth bacteria and iron bacteria in the reinjection water is very severe. The sterilization efficiencies of chlorine dioxide on the three kinds of bacteria above were studied in varies conditions. The results prove that ClO2 is suitable to apply in the oil rejection water sterilizing. When the dosage was 3.0 mg/L, the bacteria remains can meet the standards, then raise the dosage up to 5.0mg/L, the sterilization can reach or very close to 100%. Higher sterilization rates can be obtained at longer reaction time. The residue of bacterial can reach the standards just at 10 min. The influence of temperature and pH value was slightly, the best sterilization rate can be gotten at 60oC, and reach to 90% when the pH is within 7~9. Comparing with the static steel content measurements in the water before and after treatment, 1mg/L ClO2 can make the corrosion rate lower than the standard and the lowest corrosion rate is 0.036mm/a when ClO2 dosage is 4mg/L.

Inspired by analyzing principle of PSO, some non-linear strategies for decreasing inertia weight (DIW) are proposed based on the existing linear DIW (LDIW), in this paper. Then a power function is designed to unify them. Four benchmark functions are used to evaluate these strategies on the PSO performance and select the best one. The experimental results show that for most continuous optimization problems, the best one gains an advantage over the linear strategy and others. It has more varieties of the swarm at the early stages so can escape from local minimum more easily, and also can speed up the convergence of particles at the later stages to improve the performance of PSO.

The structural features and mechanism of crystallization of CuO ultrafine particles (200–450 nm) were, studied by transmission electron microscopy, as well as by thermal analyses (differential scanning calorimetry, thermogravimetric analysis, etc). The CuO ultrafine particles were not single crystals, but built up of subunits of much smaller size; between two of these subunits low-angle crystal boundaries exist. In the heating procedure, as the temperature increased, CuO ultrafine particles lost their absorbed and inclusive water gradually, the crystalline completeness was improved, and the temperature of crystallization was about 320 °C.

YBaCuO, EuBaCuO and TlBaCaCuO superconductors have been prepared by solid-state reaction. The superconducting transition of the samples was measured by the four-point and mutual inductance methods. The zero-resistance temperature and onset of diamagnetism of the best TlBaCaCuO sample have reached 120 K and 117 K respectively. Their critical currents have been measured at zero and different magnetic fields in a temperature range of 63.5 K to 78 K. The highest Jc for a TlBaCaCuO sample in zero field at 78 K reached 1630 A cm-2. In low fields, their critical current density decreases sharply when the magnetic field is increased. The results show that superconducting weak links exist among superconducting grains in all the samples. But in higher magnetic fields, their critical current density slowly decreases with increasing field; this behaviour is roughly similar to that of the Nb3Sn superconducting material. The results of the measurement of lc at different temperatures shows that the lc is proportional to (Tc-T).

Accurate band calculation for is used to determine the isomershift calibration of Fe nucleus. The semi-relativistic, all-electron, self-consistent linearized augmented planewave (LAPW) method is employed in band calculations for lattices with different spacings. The ratio of the calculated difference of the electron contact density to the volume change, and the experimental pressure dependence of the isomershift are used to deduce the calibration constant. The result thus obtained to be , is in good agreement with the recent cluster calculation. The screening effect is shown to play an essential role, and the necessity for an all-electron self-consistent calculation is emphasized.

The high-Tc Tl-Ba-Ca-Cu oxide superconductor with a critical current density Jc=1630 A cm-2 at 77 K has been prepared and high-Tc properties have been observed in this system. The zero-resistance transition temperatures T(c0)=120.3 K and Tc(AC chi )=119 K were observed by resistance and magnetic susceptibility measurements, respectively. The stability and reproduction of the materials are absolutely necessary. Thermal characteristics were investigated.

Th-Ba(Pb)-Cu oxides and Th-Ba(Zr)-Cu oxides are prepared and high-Tc properties are found in these samples. Superconductivity with midpoints of the resistive transition 88.9, 86.2 K and onsets 91.3, 93 K is observed by both magnetic susceptibility and resistance measurements, respectively. The transition width, Tc(10-90%)=4.8, 7.1 K. The nominal formula of the compounds is Th5-xBaxM2-0.5xCu5O13+y, where M is Pb, Zr.

The pseudo-ternary system SrNb2O6-NaNbO3-LiNbO2 has been investigated by means of DTA, heat treatment and X-ray diffraction techniques. It has been found that at room temperature Sr2Na(NbO3)5(S2N) is a metastable intermediate compound which has a tetragonal tungsten-bronze structure with a=12.36?, c=3.906?. LiNbO3 can be dissolved in S2N up to a limit about 10 mol% ; and in the range of 5-10mol% of LiNbO3, the S2N phase is distorted into S2N′, which belongs to the orthorhombic system and is also a metastable phase. After long time annealing at 900-1100℃, the metastable phases S2N, S2N′ will decompose into a mixture of SrNb2O6 and a phase of solid solution based on NaNbO3. The phase diagram of the corresponding binary systems and the isothermal section of the pseudo-ternary system have been established.

The variation of crystal structure types of Mgx/2Li1-xIO3 with composition and temperature has been investigated by the methods of DTA and X-ray powder diffraction both at high and room temperatures. A new type of continuous solid solutions has been found in the entire region of the binary system Mg(IIO3)2·LiIO3.For the solid solutions rich in LilO3, the crystal lattice is distorted in the x-y plane with the increasing concentration of Mg(IO3)2, While the space group changes from P63 to P1121. At the composition 3Mg(IO3)2·7LiIO3, the lattice distortion reaches a maximum,γ=120o22′. With further increasing of the concentration of Mg(IO3)2, the lattice distortion is reduced, and at the composition Mg(IO3)2·LiIO3) the space group turns back again to P63.For the solid solution rich in Mg(IO3)2, the lattice is distorted along the z axis, and has been found to be made of unit cells of heterogeneous parameters c (the effect is most prominent at the composition about 20-30mol% LiIO3). But with increasing temperature, the crystal lattice gradually changes back to unit cells with a uniform parameter.It seems probable that the lattice distortions in the solid solutions are caused by vacancies. The heterogeneous distribution of vacancies results in inhomogeneous parameters c, and it is also due to the presence of vacancies that alters the crystal fields around the anion group, causing the displacement and rotation of IO3- with the result that the lattice is distorted along x-y plane.

The crystal structure of the ideal composition compound Bi2Sr2CaCu2O8 with zero resistance temperature Tc(0) = 81.4K had been determined by X-ray powder diffraction method. The basic structure of this compound exhibits tetragonal symmetry with lattice constants a = 3.825 ?, c = 30.82 ?. The most probable space group is D4h17-14/mmm, Each unit cell contains two formula units. The arrangements of atoms in the unit cell are as follows:2Ca cations occupy 2(a) equivalent point position; 4Sr, 4Bi and 4Cu cations occupy the same equivalent point position 4(e) with respective parameters z= 0.110, 0.302, 0.445; 16O anions respectively occupy 8(g) (z = 0.445) and two 4(e) equivalent point positions (z= 0.210 and z = 0.380), The crystal structure of Bi2Sr2CaCu2O8 can be derived from Aurivillius type structure. The main feature of the structure is alternate arrangement of cations along (00z) and (1/2, 1/2, z) of tetragonal system. The other possible superconducting phases in the Bi-Sr-Ca-Cu-O system can be considered as the structure having different stacking layers along z axis.

The phase diagram, phase transition, and formation, stability and crystallization kinetics of amorphous state in the system LiIO3-NaIO3 have been investigated. The pesudo-binary system LiIO3-NaIO3 is a eutectic one, its eutectic reaction occurs at 325℃ and the composition at eutectic point is 50 m/o LiIO3. As the melt is quenched from a temperature 150℃ higher than the melting point, an amorphous state of iodate salts is obtained for the first time. The apparent transition temperature decreases when the amorphous state exists. It is found that some factors, such as intense X-ray irradiation, various humidity and fine grain size, make the crystallization speed of amorphous state increases. Crystallization speed and perfection of LiIO3 in the amorphous state is higher than NaIO3. The process of isothermal phase transition agrees with Johnson-Mehl-Avrami equation y(t) =l-exp(- btOn), when y = 0.1-0.9, where y is the quantity of crystallization. For the sample with composition of 60 m /o LiIO3, the Avrami time exponent n = 2-3 and rate constant parameter b increases exponentially with temperature. The activation energy of crystallization from amorphous state is found to be 2.21 eV.