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Based on dynamics mesh method, Computational Fluid Dynamics (CFD) simulation model of two-stage dry scroll vacuum pump was established. Simulation calculation was carried out under the condition of suction pressure at 10000Pa, 1000Pa and 100Pa,respectively. When suction pressure was 10000Pa, the numerical calculation results were basically in accordance with the experimental pumping speed. When suction pressure decreased to 1000Pa, the simulation error decreased −5.7%. When suction pressure was below 1000Pa, due to the gas regime, the calculational results deviated from the experimental results dramatically. Three-scroll profile was applied to the scroll chamberⅠ connected with the suction port, which improved the pumping speed and compression ratio as well as reducing the fluctuation of suction speed significantly. Gas expanded initially in the chamber and was then compressed by external compression. Gas compression mainly occurred in scroll chamber Ⅱ connected with the exhaust port. Gas was compressed by changing the compression chamber. The variation of the pressure in compression chamber was greatly affected by gas leakage.

CREPT has been shown to be highly expressed in most tumors and is associated with a poor prognosis, but the histologic characteristics of CREPT expression and its impact on clinical outcomes in esophageal squamous cell carcinoma (ESCC) are unclear. Therefore, we retroactively evaluated tissue microarrays (TMA) from 300 surgical cases, including 300 ESCC tissues and 161 adjacent non-tumor tissues, and pretreatment tumor biopsies from 113 concurrent chemoradiotherapy (CCRT) cases by immunohistochemistry (IHC). Notably, CREPT was increasingly expressed from non-cancerous tissues to atypical hyperplasia to tumor tissues (P < 0.01). Furthermore, patients were divided into low CREPT (≤ 8 scores) and high CREPT (> 8 scores) groups. Patients with high CREPT expressions had a worse overall survival (OS) (5-year OS: 40.9% vs. 50.1%, P=0.040) and disease-free survival (DFS) (5-year DFS: 29.5 vs. 43.0%; P=0.020) than those with low expressions. Nevertheless, only in the high CREPT subgroup did adjuvant therapy (AT) prolong the OS (5-year OS: 53.8 vs. 28.9%; P=0.020), especially for adjuvant radiotherapy (ART) (5-year OS: 85.7 vs. 28.9%; P=0.037; 5-year DFS: 85.7 vs. 22.3%; P=0.020). Surprisingly, high CREPT expressions endowed CCRT-treated patients with higher complete response rates (50% vs. 26%; P=0.018) and a favorable OS (3-year OS: 54.3 vs. 28.1%; P=0.046) compared to low expression. Overall, our findings indicate that CREPT is highly expressed in ESCC tissue compared with non-cancerous tissue and this feature is associated with a poor prognosis. Otherwise, patients with high CREPT expression were more sensitive to AT and CCRT. Moreover, CREPT could be a predictive immunohistochemical biomarker used to guide individualized clinical treatment.

Background: The purpose of this study is to explore the effect of health education with conversation map on self-management ability of rural elderly diabetic patients.Methods: 60 rural elderly diabetic patients in endocrinology department of a 3A hospital from January to December in 2019 were selected as the research objects. According to the parity of the last two digits of the hospitalization number, the odd number was divided into the control group and the even number was divided into the experimental group. The control group was given traditional health education and interactive education with conversation map was added to the experimental group. After 3 months of intervention, fasting blood glucose, 2 hours postprandial blood glucose, glycosylated hemoglobin and self-management behavior of the two groups were observed.Results: The fasting blood glucose, 2h postprandial blood glucose, glycosylated hemoglobin and self-management ability of the experimental group were significantly better than those of the control group and the difference was statistically significant (p

Gyarfas (1975) and Sumner (1981) independently, conjectured that for every tree $T$, there exists an integer-valued function $f_T(x)$ such that every graph $G$ of chromatic number larger than $f_T(\omega(G))$ contains $T$ as an induced subgraph, where $\omega(G)$ is the clique number of $G$. Gyarfas et al. proved that if $G$ contains no triangles and cycles of length 4, then $G$ contains every tree on $\chi(G)$ vertices as an induced subgraph. Besides this, they also confirmed that if $G$ contains no triangles and $\chi(G)\geq m+n$, then $G$ can induce an $(m,n)$-mop which is a special tree. In this note, we generalize these two results of Gyarfas et al. and prove that (1) if every vertex of $G$ is contained in at most $k$ triangles and $l$ cycles of length 4, and $\chi(G)\geq t+2k+2l$, then $G$ contains every tree on $t$ vertices as an induced subgraph; (2) if every vertex of $G$ is contained in at most $k$ triangles, and $\chi(G)\geq m(k+1)+n$, then $G$ contains an $(m,n)$-mop as an induced subgraph.

Purpose: The purpose of this study was to quantitatively investigate the haemodynamics and oxygen transmission of the retina. Methods: Considering the effect of Fåhraeus-Lindqvist effect on the apparent viscosity of blood and the actual haematocrit in blood vessels, this study used the currently known retinal parameters (e.g. blood flow obtained by Doppler Fourier domain optical coherence tomography, FD-OCT for short) to construct a retinal blood circulation model consisting of an asymmetric vascular network system. Results: The blood flow velocity and the vascular diameter in the retinal blood vessels satisfied the exponential relationship. The wall shear stress was related to the release of nitric oxide synthase and endothelin-1 by endothelial cells and played an important role in retinal blood flow regulation. In the retinal arteries, the oxygen tension ranged from 98 to 65 mmHg, and the oxygen saturation ranged from 97.3% to 92.2%. In the retinal veins, the oxygen tension was approximately 41.8 mmHg, and the oxygen saturation ranged from 79.2% to 77.3%. The difference in oxygen content of the arteriovenous network was 5.4 (ml O2/dl blood), and the oxygen extraction of the superior temporal arteriovenous network was 86 (μl/min*ml O2/dl blood). Conclusion: Compared with previous relevant experimental data, the numerical model established in this article demonstrates reliability. It also helps advance our understanding of the retinal pathological processes related to hemodynamics and metabolism.

Based on CFD method and dynamics mesh method, the transient flow simulation model of dry scroll vacuum pump was established. Numerical calculation was carried out under three kinds of typical working conditions of viscous flow state including under-compression, slightly over-compression and over-compression. Simulation results are in line with the results of experiment or theoretical calculation on the whole. The maximum error of pumping speed between the simulation and the experiment is about 30%, and the minimum is close to 10%. The predicted compression power accords with the theoretical prediction of approximate polytropic process. The simulation pressure inside the pump also has a consistent change process with experimental results. The contrast and analysis of the simulation model and the physical experiments suggest that the further correctly modified geometric parameters and boundary conditions according to practical situations can significantly improve the accuracy of the numerical calculation. Further analysis of the main flow phenomena and characteristics of scroll compression chamber at the discharge side during the discharge process confirms that under-compression and over-compression lead to the large variation of gas pressure and dramatic fluctuation of compression torque.

The Xuhe mafic rocks, located in Ziyang county of Shaanxi Province, are dominated by diabase-porphyrite, gabbro–diabase, diabase, and pyroxene diorite. Primitive mantle-normalized multi-element patterns show that, the Xuhe mafic rocks are enriched in large ion lithophile elements (LITE), such as Ba and Pb, depleted in K and Sr for basic rocks, and are depleted in Sr, P and Ti for pyroxene diorite. Chondrite-normalized REE patterns display LREE enrichment (LaN/YbN = 9.34–13.99) and have normalized patterns for trace element and REE similar to that of typical OIB. Detailed SEMS zircon U–Pb dating yields emplacement ages of 438.4 ± 3.1 Ma for Xuhe mafic rocks. The relatively low MgO (basic rock: 3.11–7.21 wt%; pyroxene diorite: 0.89–1.21 wt%) and Mg# (0.20–0.49) for Xuhe mafic rocks suggest that they were possibly originated from an extremely evolved magma. The rising parental mafic magmas underwent pyroxene and plagioclase fractionation. Crustal contamination of pyroxene diorite before emplacement occurred at a higher crustal level compared to other lithology in Xuhe mafic rocks. The degree of partial melt was low (5%-10%) and in garnet-spinel transition facies. Sr-Nd isotope of pyroxene diorite and enrichment mantle characteristics for Xuhe mafic rocks suggest that mafic rocks in the North Daba Mountains were derived from a mixture of HIMU, EMU and small amount of EMI components. Furthermore, this study discusses mantle geodynamic significance of Xuhe mafic rocks in the Silurian, which indicates subduction and uplift of magma caused back-arc extension.

Molybdenum disulfide (MoS2) is unfavorable for practical application in the hydrogen evolution reaction (HER) process due to its inert basal surface, inferior conductivity, and limited amount of active edge sites. For the purpose of enhancing the HER performance of this catalyst, the HER activity of its basal surface should be increased. Herein, three types of nickel-phosphorus (Ni–P) coatings—namely, low phosphorus (LP), medium phosphorus (MP) and high phosphorus (HP) —were anchored onto the surfaces of MoS2 nanoparticles via an electroless plating process; thus, three Ni–P/MoS2 composites (Ni–LP/MoS2, Ni–MP/MoS2, and Ni–HP/MoS2) were fabricated. Crystal structures, morphologies, chemical components, and HER performances of each in an alkaline solution were characterized. Both Ni–LP/MoS2 and Ni–MP/MoS2 showed a crystal nature, while the amorphous feature for Ni–HP/MoS2 was validated. The three Ni–P/MoS2 composites exhibited a higher HER activity than the pure MoS2. The HER performance of the Ni–MP/MoS2 composite was more outstanding than those of other two composites, which could be attributed to the presence of metastable nickel phosphides, and the excellent conductivity of Ni–MP coating anchored on the basal surface of MoS2.

A rapid and accurate assessment of the stability of surveying and mapping reference points is important for post – disaster rescue, disaster relief and reconstruction activities. Using Precise Point Positioning (PPP) technology, a rapid assessment of the stability of the IGS sites in China was performed after the M s 7. 0 Lushan earthquake using rapid precise ephemeris and rapid precise satellite clock products. The results show that the earthquake had a very small impact and did not cause significant permanent deformation at the IGS sites. Most of the sites were unaffected and remained stable after the earthquake.

The Early Neoproterozoic Beiyixi Formation volcanic rocks of the southern Quruqtagh comprise mainly of a suite of tholeiitic basalts, alkaline andesites, and calc-alkaline rhyolites. The rhyolites are characterized by variably fractionated enrichment in light rare earth elements (LREE) and flat in heavy rare earth elements (HREE), and strongly negative Eu anomalies. Compared to the rhyolites, the andesites also exhibit enrichment in LREE and flat HREE (chondrite-normalized values of La/Yb, and La/Sm are 13.30–41.09, 3.18–6.89 respectively). Their rare earth element patterns display minor negative Eu anomalies. Both of them exhibit coherent patterns with strongly to moderately negative anomalies of Nb, Zr, Ti, and Hf on spider diagrams. Two rhyolite and one andesite magmatic zircons with defined oscillatory zoning yielded weighted mean 206Pb/238U ages of 743 ± 7 Ma, 741±2 Ma, and 727±4 Ma. These ages are interpreted to represent the riming of volcanic eruptions. According to geochemistry and rock type, these volcanic rocks formed within a continental island-arc environment following subduction of the oceanic crust during the Early Neoproterozoic period.

The Napo-Qinzhou Tectonic Belt (NQTB) lies at the junction of the Yangtze, Cathaysia and Indochina (North Vietnam) Blocks, which is composed of five major lithotectonic subunits: the Qinzhou-Fangcheng Suture Zone (QFSZ), the Shiwandashan Basin (SB), the Pingxiang-Nanning Suture Zone (PNSZ), the Damingshan Block (DB) and the Babu-Lingma Suture Zone (BLSZ). On the basis of geochemical compositions, the Permian mafic igneous rocks can be divided into three distinct groups: (1) mafic igneous rocks (Group 1) from the Longjing region in the PNSZ and Hurun region in the BLSZ, which are characterized by intermediate Ti, P and Zr with low Ni and Cr contents; (2) mafic igneous rocks (Group 2) from the Naxiao and Chongzuo region in the DB, characterized by low-intermediate Ti, P and Zr with high Ni and Cr concentrations; and (3) mafic igneous rocks (Group 3) from the Siming region in the Jingxi carbonate platform of the northwestern margin of the NQTB, with intermediate-high Ti, P and Zr and low Ni and Cr contents. The Group 1 rocks yield a weighted mean 206 Pb/ 238 U age of 250.5±2.8 Ma and are geochemically similar to basalts occurring in back-arc basin settings. The Group 2 rocks exhibit geochemical features to those basalts in island arcs, whereas the Group 3 rocks show geochemical similarity to that of ocean island basalts. All three groups are characterized by relatively low e Nd (t) values (-2.61 to +1.10) and high initial 87 Sr/ 86 Sr isotopic ratios (0.705309-0.707434), indicating that they were derived from a subduction-modified lithospheric mantle and experienced assimilation, fractional crystallization, and crustal contamination or mixing during magmatic evolution. Accordingly, we propose the existence of an arc-back arc basin system that developed along the NQTB at the border of SW Guangxi Province (SW China) and northern Vietnam, and it was formed by continued northwestward subduction of the Cathaysian (or Yunkai) Block under the Yangtze Block, and northeastward subduction of the Indochina Block beneath the Yangtze Block during Permian time.

The Taohekou Formation is a volcanic-sedimentary terrane formed in the early Silurian in the northern Daba Mountains, China. The volcanic rocks, with dominant alkali basalts and minor mantle xenoliths, are enriched in clinopyroxene phenocrysts. Geochemical analysis shows that the composition of clinopyroxenes from different lithofacies has a close affinity. There is a liner correlation present in composition of clinopyroxenes (including phenocryst, microcrystal and xenocryst) from coarse porphyritic basalts, pillow or fine porphyritic basalts to amygdaloidal basalts. All the clinopyroxenes, except the clinopyroxenes in mantle xenoliths, show a similar pattern of trace elements and REE, which indicates that they are likely products of successive fractional crystallization from cognate magma. Clinopyroxenes in mantle xenoliths, however, are mantle xenocrysts. The crystallization pressure of clinopyroxenes gradually decreases from mantle xenolith, deep-seated xenocryst, coarse porphritic basalts, pillow or fine porphritic basalts, to amygdaloidal basalts, which are 1.92–4.41 GPa, 1.18–2.36 GPa, 1.13–2.05 GPa, 0.44–0.62 GPa and 0.14–0.28 GPa respectively. Calculation results suggest that the primary magma originated from a mantle region deeper than 68 km and stagnates in intervals of 37–68 km, 15–20 km and 5–9 km during its ascent. The alkali basalts are characterized by increasing concentrations of Si and alkaline with the magmatic evolution. Meanwhile, they are markedly enriched in LREE, and the patterns of trace elements and REE are similar to those of oceanic island basalts.

論文タイプ||論説, (経済学部号 = Economics)

論文タイプ||論説