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  • Author: Yang Dong x
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Abstract

The health status of the vaginal microenvironment, a complicated system, is an important indicator of female reproductive health. The vaginal flora is in a state of balance, and the microorganisms coexist and are interdependent to maintain the vaginal microecological balance, which is a kind of dynamic balance influenced by endogenous and exogenous factors. Vaginal infections are traditionally treated by killing microbes in the vagina. Given the extensive study of the internal vaginal environment, people have become gradually aware of the significance of maintaining the vaginal microecological balance rather than blindly using antimicrobial agents. The balance in the vaginal internal environment is disrupted during the gestation period as the secretion of progesterone increases. The imbalanced vaginal microecological environment may lead to vaginal infectious diseases. This article provides a review of the relationship between the vaginal microecology and infectious diseases during the gestation period.

Conceptual Design and Performance Analysis of an Exhaust Gas Waste Heat Recovery System for a 10000TEU Container Ship

According to operation characteristics of the main engine 9K98ME-C7, a combined turbines-exhaust gas waste heat recovery system is proposed to recover waste heat and increase system energy efficiency. Thermodynamic models based on the first thermodynamic law and the second thermodynamic law are formulated. The superheated steam yield, the total electric power yield, the first thermodynamic law efficiency, the exergy efficiency at different exhaust gas boiler working pressure, and the variation of the exergy efficiency under different feed water temperature and different steam turbine back pressure are analyzed. Thermodynamic results indicate that the most appropriate exhaust gas boiler pressure is 0.8MPa for studied main engine and the total thermal efficiency with combined turbines arrangement has climbed up to 53.8% from 48.5%.

Abstract

Background and Aims Recently, epidemiology studies of hepatitis E in different areas are attracted more attention. Extensive studies of prevalent status and clinical manifestations could help us to broaden our knowledge, so as to excellently prevent and treat hepatitis E. The study analyzed the epidemiological characteristics and clinical features of 394 cases of sporadic acute hepatitis E (AHE) in Southwest of China from 2008 to 2010.

Methods The clinical data of 394 cases with sporadic AHE in Southwest of China from 2008 to 2010 were reviewed.

Results In the 394 cases with sporadic AHE, the ratio of male/female was 1.432 : 1, and the mean age was (31.53 ± 18.12) years. Totally, 94 (23.86%) patients aged under 18, 271 (68.78%) patients aged between 18 and 60, and 29 (7.36%) patients aged above 60. The incidence rate was significantly increased in summer (P = 0.000), especially in May (14.72%) and July (13.71%). In addition, the characteristics of occupation and ethnic group distribution were migrant laborers (106/394, 26.90%) and Han people (365/394, 92.64%). The length of stay, incidence of jaundice, the peak value of total bilirubin and alanine aminotransferase in male patients were all higher than those in female patients significantly (P < 0.05). The prolonged length of stay, decreased levels of ALT/ALB/CHE, increased levels of TBil, and increased incidence of jaundice and fatigue were associated with older age significantly (P < 0.05). The differences in peak values of total bilirubin (TBil), total bile acid (TBA), glutamyltransferase (GGT), cholinesterase (CHE) between AHE group and the groups of AHE accompanied respectively by chronic hepatitis B (CHB), acute alcoholic fatty liver (AFL), nonalcoholic fatty liver disease (NAFLD) were significant (P < 0.05). In addition, no significant difference was found in length of stay and biochemical indexes among anti-HEV-IgG positive group, anti-HEV-IgM positive group and anti- HEV-IgM/IgG both positive group (P > 0.05).

Conclusions Four epidemiological characteristics, including aged between 18 and 60, male, summer and migrant laborers, are found to be associated with acute hepatitis E. The prognosis of AHE in the majority of patients was favorable, but aged above 60 years and coexistence with CHB, AFL and NAFLD could be considerede as the factors inducing the infaust prognosis.

Abstract

- The spatial distribution of surface sediment diatoms in Chaohu Lake (southeast China), and their relationships with environmental and spatial variables were analyzed in this study. The diatom assemblages were dominated by planktonic species. Three dominant species Cyclostephanos dubius, Aulacoseira granulata and Aulacoseira alpigena are unevenly distributed across the lake. The distribution of surface sediment diatoms must be subject to trophic status, hydrodynamics and other spatial variables in the lake.

Abstract

The use of ergative verbs results in the agent being backgrounded in an English sentence, and it is often used in the media together with other means such as the use of intransitive verbs, passives, and nominalized nouns to achieve the pragmatic purpose of accusation avoidance. A great deal of research has been done on the role of ergative verbs in media discourse in English as well as the acquisition of ergative verbs by learners of English as a Foreign Language (EFL). However, it remains unclear how EFL Chinese learners of advanced levels of competence, such as postgraduates of translation majors and professional translators, use ergative verbs when translating newspaper editorials from Chinese into English. Nor is it clear whether learners have acquired the requisite knowledge of ergative verbs in order to use them effectively so as to avoid blaming the agent of an action or process in translation. This study recruited 30 native Chinese-speaking translators who fell into three categories: undergraduate translators, graduate translators, and professional translators. A small parallel translation corpus was built, which consisted of 150 English translations of 5 Chinese editorials produced by the translators. Accusation-avoidance expressions in the source text and their translations were then extracted and input into an SPSS spreadsheet. The results show that the use of ergative verbs in translations by undergraduate translators is significantly higher than in translations by graduate and professional translators in terms of quantity. The results of the study may be useful for translation teaching and learning.

Abstract

Accurate tide height is crucial for the safe navigation of large deep-draft ships when they enter and leave the port. We have proposed an accurate forecasting method for the tide heights from the observation data and neural networks, which can easily calculate the tidal window period of large deep-draft ships’ navigation through long channels at high tide. Moreover, an artificial neural network is established for the tide height from the observation of tide heights before their current time node. For an ideal forecast, the neural network was optimized for one year with the tide height data of Huanghua Port. In case of large ships, their tidal characteristics of channels for are complex. A new method is proposed for the observation of multiple stations and artificial neural networks of each observation station. When ships are navigating through the port, the tide height is predicted from the observed data and forecast tide heights of multiple observation stations. Thus, a valid tidal window period is secured when the ships enter the port. Comparative analysis of the ship’s tidal window period with that of the measured one can lead us to conclude that the forecasted data has a strong correlation with the measurement. So, our proposed algorithm can accurately predict the tide height and calculate the node timing when the ship enters and depart the port. Finally, these results can be applied for the safe navigation of large deep-draft ships when the port is at high tide.

Abstract

Shell model calculations have been carried out for 90Nb nucleus with the model space in which the valence protons occupy the f5/2, p3/2, p1/2, and g9/2 orbitals and the valence neutrons occupy the p1/2, g9/2, d5/2, and g7/2 orbitals. According to the calculated results, the negative parity is from the contribution of the proton of the f5/2, p3/2, and p1/2 orbits. The moderate spin states of 90Nb are mainly due to the excitation of protons from the f5/2 and p3/2 orbits to the p1/2 and g9/2 orbits across the Z = 38 subshell closure, and the high spin states arise from the excitation of a single neutron from the g9/2 orbit into the d5/2 orbit across the N = 50 shell closure.

Abstract

As a developing country with the world’s largest population, China faces a serious challenge in satisfying its continuously increasing energy demands. Tung trees (Vernicia sp., especially V. fordii and V. montana), are multipurpose, perennial plants belonging to the Euphorbiaceae family. The unique chemical properties of tung seed oil make it one of the best known industrial drying oils. In this review, the breeding status of tung trees in China and some factors which limit the development of tung tree breeding will be summarised. Improvements in ecological performance and pathogen resistance, through to improved breeding methods, will help to rapidly expand the development and use of tung trees and their oil products in China. It is essential for tung tree breeding to advance in the future to keep pace with the increased demand.

Abstract

Energy consumption forecasting is a kind of fundamental work of the energy management in equipment-manufacturing enterprises, and an important way to reduce energy consumption. Therefore, this paper proposes an intellectualized, short-term distributed energy consumption forecasting model for equipment-manufacturing enterprises based on cloud computing and extreme learning machine considering the practical enterprise situation of massive and high-dimension data. The analysis of the real energy consumption data provided by LB Enterprise was undertaken and corresponding calculating experiments were completed using a 32-node cloud computing cluster. The experimental results show that the energy consumption forecasting accuracy of the proposed model is higher than the traditional support vector regression and the generalized neural network algorithm. Furthermore, the proposed forecasting algorithm possesses excellent parallel performance, overcomes the shortcoming of a single computer’s insufficient computing power when facing massive and high-dimensional data without increasing the cost.

Abstract

Copper germanate (CuGeO3) nanowires have been synthesized by the hydrothermal deposition process using GeO2 and copper foil as the resource as well as the deposition substrate. The factors including hydrothermal temperature, pressure and duration of the process were investigated in order to analyze the processing parameters that control the formation process, morphology and size of the nanowires. The dependence of the nanowires properties on the growth conditions shows that the CuGeO3 nanowires can be synthesized in a large range of different hydrothermal parameters from 400 °C to 250 °C. The hydrothermal pressure has an important effect on the formation and growth of the CuGeO3 nanowires. The CuGeO3 nanowires exhibit good electrochemical cyclic voltammetry characteristics owing to offering many advantages in sensing applications including their small size, high aspect ratio and conductance.