Abstract With the accelerated construction of pumped-storage power stations, high-head and high-capacity pumped-storage units are gradually becoming the mainstream of development. When operated ...on-site, the high-head and high-capacity pumped-storage units reflect the phenomenon of special frequency of the head cover vibration of the water pump, which has attracted widespread attention from the industry. In order to deeply reveal the flow mechanism of pumped-storage units, model experiments on the head cover were conducted through the similarity conversion principle between the model and the prototype. The experiment results show that the occurrence of specific frequency in the Head cover of the water pump during operation is due to the rotating flow separation in the vaneless area.
Prostate cancer is one of the most common male malignant neoplasms; however, its causes are not completely understood. A few recent studies have used gene expression profiling of prostate cancer to ...identify differentially expressed genes and possible relevant pathways. However, few studies have examined the genetic mechanics of prostate cancer at the pathway level to search for such pathways. We used gene set enrichment analysis and a meta-analysis of six independent studies after standardized microarray preprocessing, which increased concordance between these gene datasets. Based on gene set enrichment analysis, there were 12 down- and 25 up-regulated mixing pathways in more than two tissue datasets, while there were two down- and two up-regulated mixing pathways in three cell datasets. Based on the meta-analysis, there were 46 and nine common pathways in the tissue and cell datasets, respectively. Three up- and 10 down-regulated crossing pathways were detected with combined gene set enrichment analysis and meta-analysis. We found that genes with small changes are difficult to detect by classic univariate statistics; they can more easily be identified by pathway analysis. After standardized microarray preprocessing, we applied gene set enrichment analysis and a meta-analysis to increase the concordance in identifying biological mechanisms involved in prostate cancer. The gene pathways that we identified could provide insight concerning the development of prostate cancer.
The influences of sludge on horizontal electric current (HEC) in metal pad of cell were analyzed using a 3D model. The results show that the sludge located in the center has small influence on the ...HEC. And the sludge located in the side has great effect on the HEC. As the length of sludge increases, the negative peak move from the side to the middle. Moreover, it produces a large positive peak close to the side. The sludge located in side has small influence on the cathode voltage drop than that of the sludge located in center.
This work is aimed at studying the foaming behavior of polypropylene (PP) with supercritical carbon dioxide (scCO
2). The effects of saturation time, foaming temperature, saturation pressure and ...depressurization rate on the foam structure and volume expansion ratio were investigated. A likely foaming zone delimited by the upper and lower limits for foaming temperature and saturation pressure was determined. The upper limit for foaming was dictated by the melt strength of the PP while the lower one by the deformability of the PP. The maximum likely foaming temperature range was very narrow, only about 4
°C, whatever the saturation pressure, showing the poor foamability of PP. There was a sort of equivalence between increasing foaming temperature and increasing saturation pressure in terms of the foamability. However, a lower foaming temperature and a higher saturation pressure were more favorable for obtaining uniform foam than a higher foaming temperature and a lower saturation pressure. At given foaming temperature and saturation pressure, increasing depressurization rate led to an increase in cell density. However, both the cell size and the foam volume expansion ratio first increased with increasing depressurization rate, reached a maximum at some point and then decreased with a further increase in depressurization rate.
Packing optimization problems aim to seek the best way of placing a given set of rectangular cartons within a minimum volume rectangular container. Currently, packing optimization methods either have ...difficulty in finding a globally optimal solution or are computationally inefficient, because models involve too many 0-1 variables and because use of just a single computer. This study proposes a distributed computation method for solving a packing problem by a set of personal computers via the Internet. First, the traditional packing optimization model is converted into an equivalent model containing many fewer 0-1 variables. Then the model is decomposed into several sub-problems by dividing the objective value into many intervals. Each of these sub-problems is a linearized logarithmic program expressed as a linear mixed 0-1 problem. The whole problem is solvable and reaches a globally optimal solution. The numerical examples demonstrate that the proposed method can obtain the global optimum of a packing problem effectively.
Toxoplasmosis is caused by the intracellular protozoan Toxoplasma gondii. It is anopportunistic zoonosis in warm-blooded animals and humans, with a worldwide distribution. Toxoplasma gondii dense ...granule protein 16 (TgGRA16) can modulate some functions in host cells and is considered a significant virulent factor of the parasite. The present study reports sequence variation in TgGRA16 gene among T. gondii strains from different hosts and geographical locations, and the construction of phylogenetic relationships of these T. gondii strains based on sequences of TgGRA16, and analysis of B cell epitopes in TgGRA16. Our results showed that all TgGRA16 gene sequences were 1518 bp and the C+G contents ranged from 52.17% to 52.59%. Sequence variation in the TgGRA16 gene was 0-1.51%. Phylogenetic analysis revealed that TgGRA16 gene sequence could not be used to differentiate the different T. gondii genotypes. Six B cell epitopes were predicted in TgGRA16. These results indicated that TgGRA16 gene is not an ideal marker for studying genetic relationships of T. gondii isolates, but may represent a good vaccine candidate against toxoplasmosis.
Estimated central systolic blood pressure (cSBP) and amplification (Brachial SBP-cSBP) are non-invasive measures potentially prognostic of cardiovascular (CV) disease. No worldwide, multiple-device ...reference values are available. We aimed to establish reference values for a worldwide general population standardizing between the different available methods of measurement. How these values were significantly altered by cardiovascular risk factors (CVRFs) was then investigated.
Existing data from population surveys and clinical trials were combined, whether published or not. Reference values of cSBP and amplification were calculated as percentiles for 'Normal' (no CVRFs) and 'Reference' (any CVRFs) populations. We included 45,436 subjects out of 82,930 that were gathered from 77 studies of 53 centres. Included subjects were apparently healthy, not treated for hypertension or dyslipidaemia, and free from overt CV disease and diabetes. Values of cSBP and amplification were stratified by brachial blood pressure categories and age decade in turn, both being stratified by sex. Amplification decreased with age and more so in males than in females. Sex was the most powerful factor associated with amplification with 6.6 mmHg (5.8-7.4) higher amplification in males than in females. Amplification was marginally but significantly influenced by CVRFs, with smoking and dyslipidaemia decreasing amplification, but increased with increasing levels of blood glucose.
Typical values of cSBP and amplification in a healthy population and a population free of traditional CVRFs are now available according to age, sex, and brachial BP, providing values included from different devices with a wide geographical representation. Amplification is significantly influenced by CVRFs, but differently in men and women.
To further study the corrosion mechanism of pure phase La(Fe,Si)13, Ce were added into the LaFe11.5Si1.5 compounds to facilitate phase formation and improve corrosion resistance and magnetic ...properties. The corrosion test conducted on the pure phase La1-xCexFe11.5Si1.5 (x = 0.1, 0.2, 0.3) revealed a significant number of minute corrosion pits with irregular shapes such as round, square and triangular after only 1 h of corrosion in tap water. However, in the case of La0.7Ce0.3Fe11.5Si1.5 compound, the number of corrosion pits was significantly lower. Potentiodynamic polarization curves showed that Ecorr goes up from −0.76 V to −0.59 V, and the Icorr goes down from 4.92 × 10−6 A/cm2 to 2.46 × 10−6A/cm2 as a result of Ce addition from 0.1 to 0.3. With the increase of Ce content, the corrosion resistance of La1-xCexFe11.5Si1.5 compounds was improved. Adding Ce element in the LaFe11.5Si1.5 compounds can also enhance the magnetocaloric effect. Significant extra spike-shaped peaks were observed on the M-H curves of La0.8Ce0.2Fe11.5Si1.5 and La0.7Ce0.3Fe11.5Si1.5, indicating a strong first-order magnetic phase transition. Furthermore，-△SM values improved from 21.2 J/kg K to 51.6 J/kg K by increasing Ce from 0.1 to 0.3.
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