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Open access

Xiao-Yan Xu, Janusz Mindykowski and C. Chen

Study on Hybrid Filtering Solution for Marine Electric Network

This paper presents a Hybrid APF/PFC/PPF Circuit (active power filtering and power factor correction circuit aided by shunt passive filter) for harmonic suppression and power factor correction in a marine electric network. By employing the proposed hybrid circuit, marine electric power network voltage and current can be maintained as being sinusoidal, and the power factor is close to 1. The effectiveness of the proposed method that is applied to a marine electric network is demonstrated through a simulation experiment. The results show that the expected performances are achieved.

Open access

Bin Xu and Yan Liu

Abstract

The primary evaluation of the economic losses caused by water pollution in Shanghai in the year 2009 is made by classification approach in order to provide basis for decision of the relative water management policy. The result shows that the portion of water pollution losses in GDP of Shanghai was 2.7%, which was still lower than the average level of whole China despite of the local high population density and the scale of industry, suggesting to some extent the continuous attention in water protection paid by Shanghai government.

Open access

Xuesong Fu, Yan Yang, QuanYang Ma, Xiaodong Peng and Tiancai Xu

Abstract

Mg-0.5Si-xSn (x=0.95, 2.9, 5.02wt.%) alloys were cast and extruded at 593K (320 oC) with an extrusion ratio of 25. The microstructure and mechanical properties of as-cast and extruded test alloys were investigated by OM, SEM, XRD and tensile tests. The experimental results indicate that the microstructure of the Mg-0.5Si-xSn alloys consists of primary α-Mg dendrites and an interdendritic eutectic containing α-Mg, Mg2Si and Mg2Sn. There is no coarse primary Mg2Si phase in the test alloys due to low Si content. With the increase in the Sn content, the Mg2Si phase was refined. The shape of Mg2Si phase was changed from branch to short bar, and the size of them were reduced. The ultimate tensile strength and yield strength of Mg-0.52Si-2.9Sn alloy at the temperature of 473K (200 oC) reach 133MPa and 112MPa respectively. Refined eutectic Mg2Si phase and dispersed Mg2Sn phase with good elevated temperature stability are beneficial to improve the elevated temperature performance of the alloys. However, with the excess addition of Sn, large block-like Mg2Sn appears around the grain boundary leading to lower mechanical properties.

Open access

Yi-Hui Xu and Cai-Mei Yan

Abstract

Let A(p) denote the class of functions of the form f(z) = zp Σ k=1+p akzk (p ∈ N = {1, 2, 3,...}) which are analytic in the open unit disk U = {z : z ∈ C and |z| < 1} By making use of the Noor integral operator, we obtain some interesting properties of multivalent analytic functions.

Open access

Su-Hua Zheng, Min Yan, Tiffany Field and Xiao Xu

Abstract

Objective

To evaluate the available evidence from randomized controlled trials (RCTs) of auricular acupressure (AA) therapy for preventing constipation in breast cancer patients undergoing chemotherapy.

Methods

The following databases were searched from their inception until August 2017: Ovid Medline, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), and Allied and Alternative Medieine (AMED). We also searched four Chinese databases: Chinese BioMedical Database (CBM), China National Knowledge Infrastructure (CNKI), WANFANG Data, and Chinese VIP Database. Only the RCTs related to the effects of AA therapy on preventing constipation in breast cancer patients undergoing chemotherapy were included in this study. Quantitative syntheses of data from RCTs were conducted using RevMan 5.3 software. Study selection, data extraction, and validation were performed independently by two authors. Cochrane criteria for risk of bias were used to assess the methodological quality of the trials.

Results

Four RCTs met the inclusion criteria, and most were of low methodological quality. Study participants in the AA plus routine care group showed significantly greater improvements in the response rate (risk ratio [RR] = 1.27, 95% confidence interval [CI] [1.14,1.42], P < 0.01) with low heterogeneity χ2 = 2.31, P = 0.31, l2 = 14%). In addition, when compared with routine care alone, one RCT suggested favorable statistically significant effects of AA plus routine care on Constipation Assessment Scale (CAS; mean difference [MD] = -5.07,95% CI [-6.86, -3.28], P < 0.01). Furthermore, when compared with routine care alone, one RCT suggested positive statistically significant effects of AA plus routine care on Patient Assessment of Constipation-Quality of Life (PAC-QOL; MD = -1.26,95% CI [-1.59, -0.93], P < 0.01).

Conclusions

Overall, as a potential safety therapy, only weak evidence can support the hypothesis that AA can effectively prevent constipation in breast cancer patients undergoing chemotherapy.

Open access

Yan Zhang, Changbin Quan, Weimin Li, Liying Chen, Xiaoyan Song, Jianbin Xu and Guangqing Zhu

Abstract

Background

Pituitary stalk interruption syndrome (PSIS) is characterized by a thin or interrupted pituitary stalk, impairing delivery of hypothalamic hormones to the pituitary, and anterior pituitary dysplasia.

Objectives

To summarize the manifestations and treatment of PSIS.

Methods

We performed a meta-analysis of PSIS research published between January 1, 2004 and December 31, 2013. Chinese databases were searched using the terms “pituitary stalk interruption syndrome”, “PSIS”, and “vertebral handle interrupts syndrome”; and results limited to clinical studies. Age of onset and diagnosis, sex, symptoms at presentation, main clinical signs, magnetic resonance imaging (MRI), laboratory results, and other data were extracted from qualifying studies.

Results

We included 311 cases from 33 papers in the meta-analysis. The male:female ratio was 257:54, and 183 of the 311 patients had a history of abnormal birth or cerebral hypoxia. MRI showed 239 cases of missing and 62 cases of tapered pituitary stalk. Multiple pituitary hormone deficiency was identified in 190 cases, and single growth hormone deficiency in 75. There were significant associations between missing pituitary stalk and multiple pituitary hormone deficiency, and pituitary stalk tapering and single hormone deficiency (P < 0.01). The clinical signs included growth retardation and the absence or delay in development of secondary sexual characteristics. Therapy was usually inadequate, with only 12 patients (3.86%) undergoing growth hormone replacement.

Conclusions

Abnormal delivery and cerebral hypoxia may be important causes of PSIS, and MRI is valuable for its diagnosis. Measuring the levels of pituitary hormones is necessary for timely diagnosis and treatment.

Open access

Lian Fei Cao, Huo Qing Zheng, Qi Yan Shu, Fu Liang Hu and Zi Wei Xu

Abstract

China is the largest producer and exporter of royal jelly in the world. The high production of royal jelly in China is mainly attributed to a high royal jelly-producing lineage of honeybees (Apis mellifera) (HRJB). However, few studies have been conducted on the genetic characterization of HRJB. In this study, the mitochondrial DNA intergenic region between cytochrome oxidase I and II (COI-COII) and the mitochondrial NADH dehydrogenase subunit 2 sequences (ND2) were determined for 90 HRJB colonies, collected from the regions of China where HRJB originated, and 25 unimproved A. m. ligustica colonies from China. COI-COII sequence analysis revealed two mitotypes (C1 and C2d) in HRJB colonies and one mitotype (C1) in unimproved A. m. ligustica colonies. The main mitotype (C1) in HRJB accounted for 93% of the colonies. Based on ND2 sequences, four and two mitotypes were found in HRJB and unimproved A. m. ligustica colonies, respectively. Sequence alignment showed that nucleotides in three positions of the ND2 sequence were different between the main mitotype of HRJB and that of unimproved A. m. ligustica. Our study suggested that HRJB was bred from A. m. ligustica and possibly had genetic characteristics different from unimproved A. m. ligustica.