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[en] Objective: To assess the severity of acute pancreatitis (AP) by observing the changes of the plasma renin activity (PRA) and plasma angiotensin-II levels in those patients. Methods: Plasma concentrations of the PRA and AGT-II were determined with RIA in patients with severe acute pancreatitis (SAP), mild acute pancreatitis (MAP), acute cholecystitis (AC), acute appendicitis (AA), acute phase of peptic ulcer (PU, only AGT-II was measured) and in healthy controls (HC). In SAP and MAP patients, a second determination was done. Results: The plasma levels of the PRA and AGT-II within 24 hours after admission were 3.84 ±1.92 ng/ml·h, 386.68 ±178.53 pg/ml in SAP. A group; 1.88 ± 0.93 ng/ml·h, 142.68 ± 83.57 pg/ml in MAP. A group; 0.68 ±0.45 ng/ml·h, 43.51 ± 31.04 pg/ml in HC group. These variables are significantly higher in SAP. A and MAP. A groups than those in other groups. During the recovery period, they were 1.34 ± 0.76 ng/ml·h, 44.71 ± 27.93 pg/ml in SAP. R group, and 1.18 ± 0.69 ng/ml·h, 41.82 ± 17.88 pg/ml in MAP. R group. There were significant differences (p < 0.05) when comparing the SAP. A group with MAP. A group, and comparing HC group with SAP. A group and with MAP. A group respectively. The paired compartment of the AP (SAP. R/SAP. A and MAP. R/MAP. A) are also significantly differences (p < 0.05). For the same group of AP patients at different stage (SAP. R/SAP. A and MAP. R/MAP. A) those were also significant difference (p < 0.05 ). There are also significant (p < 0.05) difference comparing those values in SAP. A and MAP. A group with the AC, AA and PU group respectively. Conclusion: 1. RAAS are activated in patients with AP on account of the circulatory hypovolemia with various causes. The degree of activation is positively correlated to the seriousness of the disease process. Increase of the plasma level of AGT-II in patients with AP is a compensatory mechanism but it exacerbates the microcirculation impediment of the pancreas
[en] Multifunctional hydrogels that simultaneously possess semi-interpenetrating networks structure, strong photoluminescence, and temperature sensitivity were successfully fabricated based on the crosslink of poly(acrylamide) (PAAm) in the presence of poly(N-isopropylacrylamide) (PNIPAM) and CdTe quantum dots (QDs) at a mild condition. With the increase of external temperature, the photoluminescence (PL) intensity and emission peak of the hydrogels gradually decreased and red-shifted, respectively. Decreasing the temperature, the PL intensity and emission peak of the hydrogels could back to their initial values again. Moreover, drug-release experiments on the multifunctional hydrogels demonstrated that the release rate can be tuned by the environmental temperature and the content of PNIPAM. In addition, biocompatible hyperbranched polyglycerol functionalized QDs (QD-HPGs) instead of pristine QDs can also be incorporated into the hydrogels, affording biocompatible hydrogels which could still exhibit temperature-sensitive photoluminescence and drug-release behaviors. Highlights: → Multifunctional hydrogels that simultaneously possess semi-interpenetrating networks structure, strong photoluminescence, and thermo-sensitive optical and drug-release behaviors were presented for the first time. → These multifunctional hydrogels can be facilely fabricated through the crosslink of poly(acrylamide) in the presence of poly(N-isopropylacrylamide) and CdTe quantum dots at a mild condition. → It is believed that the multifunctional hydrogels will find potential applications in thermo-sensitive devices and drug delivery.
[en] Inelastic neutron scattering spectra from C-15 phase superconducting alloys V2Hf, V2Ta, V2Hf/sub 0.8/Ta/sub 0.2/, V2Zr/sub 0.5/ Hf/sub 0.5/, and V2Zr/sub 0.5/Hf/sub 0.33/Ta/sub 0.17/ were measured by the neutron time-of-flight method, and their relative phonon densities of states were evaluated. The present results show that the phonon frequencies soften with an increase of the superconducting transition temperature T/sub c/, and harden with a decrease of the T/sub c/, which is in agreement with our previous results in our paper ''The effect of Nb on phonons of superconductors C-15 V2Zr and V2(Zr/sub 0.5/Hf/sub 0.5/).''1 This means that for these superconductors the elastic softening plays a role in enhancing T/sub c/ to some extent. It seems that between V2Zr or V2Hf and V2(Zr/sub 0.5/Hf/sub 0.5/) there exists an essential difference, which causes T/sub c/ to increase and the phonon frequencies to soften for the former, while T/sub c/ decreases and the phonon frequencies harden slightly for the latter after adding small amounts of Nb or Ta. This can be considered to be the result of hybridization of conduction bands, which is studied by means of the LMTO (linear combination of muffin-tin orbitals) method.12
[en] The National Economic and Social Development Plans (NESDPs) of cities in China, given their comprehensive, integrated and strategic nature, have significant and profound impacts on the development of cities and their embedded ecological environments. Strategic Environmental Assessments (SEAs) on city NESDPs have the potential to improve environmental policy integration at strategic level and to safeguard the sustainable development of cities. However, these plans are normally exempted from the current SEA requirement in China. We argue that it is more feasible to apply SEAs on city NESDPs before SEAs are expanded to higher level NESDPs in China. This article attempts to propose a China-specific institutional design for SEAs on city NESDPs based on experiments in selected cities and within the current legal framework. To obtain a holistic view about the long-term development of cities, more qualitative and descriptive analysis-based assessment methods should be adopted to broaden participation, to encourage the exchange of information and to reach consensus. - Highlights: → National Economic and Social Development Plans for Cities (NESDPs) in China is a very popular and significant decision made by municipal government. → We propose a institutional framework to conduct strategic environmental assessment to NESDPs. → The key features of the institutional framework are the independent SEA approval committee and a professional consulting agency.
[en] Objective: To study the antitumour effect of irradiation combination with recombined pEgr-p16 plasmid on melanoma B16 cells. Methods: pEgr-p16 plasmids were transfected into B16 cell line. Quantitative RT-PCR, flow cytometry and MTT methods were used to detect the expression of p16, cell apoptosis and inhibition effect, respectively. Results: The p16 expressions in different doses X-ray irradiation group were about 3.78-6.67 times higher than that in sham-irradiation group (P<0.01). The expressions of p16 gradually increased with time after exposure to 2 Gy X-ray irradiation and reached to maximum at 72 h. Apoptosis rate in transfected p16 combined with irradiation group was higher than that in either plasmid or irradiation group alone (P<0.05-0.01). The number of pEgr-p16-transfected B16 cells exposed to 2 Gy X-ray irradiation was significantly less than those in other experimental groups (P<0.05-0.001). Conclusions: pEgr-p16 gene transfection combined with irradiation could suppress melanoma B16 cell growth. And the inhibition was more effective than those in gene- or irradiation-therapy alone. (authors)
[en] This paper introduces the function of TNPS refueling machine, the structure of rod cluster assembly protective jacket, and the condition of functionality recovering. It also describes some problems found when fuel assemblies and rod cluster assemblies are rearranged and replaced during refueling outage, as well as the analysis and processing of problems. In addition, it investigates the general causes of problems by disassembling inspection on rod cluster assembly protective jacket. (authors)
[en] The atomization and combustion flowfield of the combustion chamber with swirl-nozzle were simulated using different biofuels; the thermodynamic cycle of the aircraft engine system were also analyzed, influences of biofuels on the combustion characteristics and performance of aircraft engine system were explored. Results show that viscosity and caloric value are key factors affecting the atomization and combustion characteristics of biofuels, and then dominate the distribution of the temperature and NO concentration. Due to the characteristic of low viscosity and low caloric value for biofuels adopted, the biofuels accumulate near the head of combustion chamber, and the corresponding NO emission is lower than that it has for conventional kerosene. When biofuels with low caloric value are used under the operation condition which is same as the condition for the conventional kerosene, lower turbine inlet temperature, lower thrust and higher specific fuel consumption would be achieved for the aircraft engine. - Highlights: • Influences of biofuels properties on combustion characteristic are explored. • Effects of biofuels on cycle parameters of aircraft engine are discussed. • Viscosity and caloric value are key factors affecting combustion of biofuels. • NO emission becomes lower when biofuels with low caloric value is adopted. • The performance of aircraft engine becomes worse for biofuels with low caloric value.
[en] We present a one-step approach to combine the functional features of upconverting NaYF_4:Yb:Er nanoparticles and thermosensitive poly(N-isopropylacrylamide) (PNIPAM) for luminescence thermometry. Dual-functional hydrogel that simultaneously possesses strong upconversion luminescence (UL) and temperature responsibility was fabricated based on the crosslinking of poly(acrylamide) in the presence of PNIPAM and NaYF_4:Yb:Er nanoparticles. The obtained hydrogel exhibited reversibly temperature-dependent UL and highly enhanced sensibility. The luminescence temperature sensitivity reached 1.9% per °C and 0.7% per °C in the range of 27–33 °C and 35–45 °C, respectively. The maximum sensitivity could even reach 26.5% per °C in the range of 33–35 °C. Considering the facile fabrication process and fine luminescence thermometry performance, this study thus opens up new opportunities for preparing highly sensitive temperature sensors. - Highlights: • One-step fabrication of upconverting and thermosensitve PAAm/PNIPAM/NaYF_4:Yb:Er hydrogel is reported. • The combination of functional features of NaYF_4:Yb:Er upconversion nanoparticles (UCNPs) and thermosensitve PNIPAM can efficiently enhance the luminescence temperature sensitivity of UCNPs. • The luminescence temperature sensitivity of hydrogel can respectively reach 1.9% per °C and 0.7% per °C in the range of 27–33 °C and 35–45 °C. • The maximum sensitivity can even reach 26.5% per °C in range of 33–35 °C
[en] Mn-doped NiCuZn ferrites with compositions of (Ni0.2Cu0.2Zn0.6)O(Fe2-x,MnxO3)0.98 (x=0, 0.02, 0.04, 0.06) were prepared by a novel sol-gel auto-combustion process. The synthesized nano-sized ferrite powders can be sintered at 900 deg. C, and the sintered ferrites are characterized by fine-grained microstructural feature and high permeability. Mn content in formulations largely affects the grain size and main electromagnetic properties of sintered NiCuZn ferrites. With increasing Mn content, the initial permeability is significantly increased, while the electrical resistivity and quality factor are decreased. The dielectric constant and dissipation factor are also affected by the incorporation of MnO2. The possible mechanism for the influence of MnO2 on the electromagnetic properties was discussed
[en] Highlights: • Band structures of ZnTe:O alloy highly depends on the status of oxygen. • Clustered oxygen lowers the bandgap while isolated oxygen increases the bandgap. • The solar adsorption efficiency of ZnTe:O can be improved by oxygen clustering. -- Abstract: First-principles calculations reveal that band structures of ZnTe:O alloys highly depend on the configuration of oxygen in the alloy. For alloys with isolated oxygen, the calculated band structure shows the formation of intermediate states between valence and conduction band and the shift of conduction band to higher energy level. It expands the gap between valence and conduction band. For alloys with clustered oxygen, the formation of intermediate band is still observed, while the gap between valence and conduction band is decreased. For alloys with oxygen impurities adjacent to Zn vacancy, the band structure only shows the decrease of the gap between valence and conduction band without the formation of any intermediate band. These results suggest the critical role of Zn–O bonding in determining the energy level of the impurity states. On the basis of our results, a possible band engineering approach is suggested in order to improve the performance of ZnTe:O alloy as intermediate band solar adsorbent