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Open access

Mingxiang Ling, Huimin Li and Qisheng Li

Abstract

Measurement uncertainty evaluation based on the Monte Carlo method (MCM) with the assumption that all uncertainty sources are independent is common. For some measure problems, however, the correlation between input quantities is of great importance and even essential. The purpose of this paper is to provide an uncertainty evaluation method based on MCM that can handle correlated cases, especially for measurement in which uncertainty sources are correlated and submit to non-Gaussian distribution. In this method, a linear-nonlinear transformation technique was developed to generate correlated random variables sampling sequences with target prescribed marginal probability distribution and correlation coefficients. Measurement of the arm stretch of a precision centrifuge of 10-6 order was implemented by a high precision approach and associated uncertainty evaluation was carried out using the mentioned method and the method proposed in the Guide to the Expression of Uncertainty in Measurement (GUM). The obtained results were compared and discussed at last.

Open access

Ying Li and Baotian Dong

Abstract

The existing cloud data models cannot meet the management requirements of structured data very well including a great deal of relational data, therefore a two-layer cloud data model is proposed. The composite object is defined to model the nested data in the representation layer, while a 4-tuple is defined to model the non-nested data in the storage layer. Referring the relational algebra, the concept of SNO (Simple Nested Object) is defined as basic operational unit of the algebraic operations; the formal definitions of the algebraic operations consisting of the set operations and the query operations on the representation layer are proposed. The algorithm of extracting all SNOs from a CAO (Component-Attribute-Object) set of a composite object is proposed firstly as the foundation, and then as the idea; the pseudo code implementation of algorithms of the algebraic operations on the storage layer are proposed. Logic proof and example proof indicate that the definition and the algorithms of the algebraic operations are correct.

Open access

Minghan Yang, Xuedong Gao and Ling Li

Abstract

Although Clustering Algorithm Based on Sparse Feature Vector (CABOSFV) and its related algorithms are efficient for high dimensional sparse data clustering, there exist several imperfections. Such imperfections as subjective parameter designation and order sensibility of clustering process would eventually aggravate the time complexity and quality of the algorithm. This paper proposes a parameter adjustment method of Bidirectional CABOSFV for optimization purpose. By optimizing Parameter Vector (PV) and Parameter Selection Vector (PSV) with the objective function of clustering validity, an improved Bidirectional CABOSFV algorithm using simulated annealing is proposed, which circumvents the requirement of initial parameter determination. The experiments on UCI data sets show that the proposed algorithm, which can perform multi-adjustment clustering, has a higher accurateness than single adjustment clustering, along with a decreased time complexity through iterations.

Open access

Hong-Ling Li, Zhi Chai, Garry X. Shen and Chun-Yang Li

Abstract

This study evaluated the antioxidant activity of ethanol extracts of Osmanthus fragrans (Thunb.) Lour. flowers (EOF) and identified phenolic compounds in EOF using liquid chromatography-mass spectrometry. Nine compounds, 3-O-caffeoylquinic acid, caffeic acid 4-O-glucoside, salidroside, 5-O-coumaroylquinic acid, 4-O-coumaroylquinic acid, acteoside, ligustroside, fucosterol and arjunolic acid were identified. To our knowledge, caffeic acid 4-O-glucoside, 5-O-coumaroylquinic acid and 4-O-coumaroylquinic acid have not been detected in EOF. In vitro antioxidant activity analysis demonstrated that EOF possessed strong DPPH and ABTS radicals scavenging activity with EC50 values at 0.26±0.06 mg/mL and 0.36±0.01 mg/mL, respectively, and reducing power with Ab0.5 value at 13.04±0.16 μg/mL. The value of oxygen radical absorbance capacity (ORAC) was 333.23±13.39 μmol Trolox/g. Antioxidant activity assay in human umbilical vein endothelial cells (HUVEC) showed that the activity of superoxide dismutase (SOD) was significantly improved and the reactive oxygen species (ROS) was removed effectively from cells when treated with EOF of 300~3000 μg/L.

Open access

Li-ping Sun, Hui-yu Li, Xiao-ling Yi, Aime Niyonsaba, Ning-fang Wang and Sheng-hua Jie

Abstract

Objective Microvesicles (MV) released from blood cells play an important role in the progress of diseases. The purpose of this study is to detect circulating MV level of patients suffering from severe fever with thrombocytopenia syndrome (SFTS).

Methods The plasma samples of SFTS patients and healthy controls were collected. And MV from samples were isolated and MV levels were detected quantitatively.

Results The results showed that the level of the circulating MV in SFTS patients was obviously higher than that of the healthy control, with statistically significant difference. Further analysis revealed that MV level was relevant to the severity of SFTS patients, namely the higher the concentration of MV, the more severity of the disease. Linear correlation analysis showed that the circulating MV level in SFTS was correlated positively with leukocyte count (r = 0.243, P < 0.05), but no correlation with the platelet count (r = 0.193, P >0.05).

Conclusions We demonstrated that there existed high level of circulating MV in SFTS patients, and the level of circulating MV had a close relationship with the severity of the disease and leukocyte count. Therefore, monitoring the level of circulating MV may provide a new indicator for predicting the prognosis of SFTS patients.

Open access

Chen-Yang Li, Yan-Hui Liu, Yu-Nan Ji, Ling-Li Xie and Zhen-Hua Hou

Abstract

Objective

This meta-analysis aims to evaluate the effects of traditional Chinese medicine (TCM) nursing combined with conventional nursing in patients with chronic obstructive pulmonary disease (COPD).

Methods

Data were collected from the databases of PubMed, Embase, the Cochrane Library, Web of Science, Google Scholar, China National Knowledge Infrastructure (CNKI), WanFang Data (WF) and VIP Database, including literature regarding the effects of TCM nursing combined with conventional nursing in patients with COPD published before January 2017. The Jadad scale was used to assess the quality of the eligible literature. The weighted mean differences and odds ratios were used to analyze St. George’s Respiratory Questionnaire (SGRQ) scores, pulmonary function, hospital stay, and clinical efficacy.

Results

Twenty-three randomized controlled trials comprising 3116 cases (TCM nursing combined with the conventional nursing group: 1559; conventional nursing group: 1557) met the inclusion criteria. TCM nursing combined with conventional nursing was associated with a lower SGRQ score, higher forced expiratory volume in 1 second (FEV1) value, higher FEV1/forced vital capacity (FVC) value, higher FEV1% value, higher FEV1 predicted value, shorter hospital stay, and preferable clinical efficacy.

Conclusions

TCM nursing combined with conventional nursing emphasized that dialectical nursing can be performed preferably in patients with COPD.

Open access

Chen Xiao-Qiang, Hao Chun-Ling, Qiu Hao and Li Min

Abstract

In this paper, a low kilo-volt-ampere rating zigzag connected autotransformer based 36-pulse rectifier system supplying vector controlled induction motor drives (VCIMD) is designed, modeled and simulated. Detailed design procedure and magnetic rating calculation of the proposed autotransformer and interphase reactor is studied. Moreover, the design process of the autotransformer is modified to make it suitable for retrofit applications. Simulation results confirm that the proposed 36-pulse rectifier system is able to suppress less than 35th harmonics in the utility line current. The influence of load variation and load character is also studied to demonstrate the performance and effectiveness of the proposed 36-pulse rectifiers. A set of power quality indices at AC mains and DC link are presented to compare the performance of 6-, 24- and 36-pulse AC-DC converters.

Open access

Chen Zhang, Fangxu Chen, Zhixin Ling, Gang Jian and Yuanliang Li

Abstract

Microstructure and dielectric properties of La2O3 doped Ti-rich barium strontium titanate ceramics, prepared by solid state method, were investigated with non-stoichiometric level and various La2O3 content, using XRD, SEM and LCR measuring system. With an increase of non-stoichiometric level, the unit cell volumes of perovskite lattices for the single phase Ti-rich barium strontium titanate ceramics increased due to the decreasing A site vacancy concentration V″A. The unit cell volume increased and then decreased slightly with the increasing La2O3 content. Relatively high non-stoichiometric level and high La2O3 content in Ti-rich barium strontium titanate ceramics contributed to the decreased average grain size as well as fine grain size distribution, which correspondingly improved the temperature stability of the relative dielectric constant. The relative dielectric constant єrRT, dielectric loss tanδRT and the maximum relative dielectric constant єrmax decreased and then increased with the increasing non-stoichiometric level. With the increase of La2O3 doping content, the relative dielectric constant єrRT increased initially and then decreased. The maximum relative dielectric constant єrmax can be increased by applying low doping content of La2O3 in Ti-rich barium strontium titanate ceramics due to the increased spontaneous polarization.

Open access

Hui Li, Ya-ling Wang and De-ying Tian

Abstract

Objective To observe the therapeutic effects of intraperitoneal injection of antibiotics, intravenous injection of terlipressin, and combined treatment of coloclysis and plasma exchange on hepatic failure(HF), the subjects included 494 inpatient cases of hepatic failure who were treated in Department of Infectious Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China from 1997 to 2008.

Methods The patients that met the inclusion criteria were divided into intraperitoneal antibiotic injection group, intravenous terlipressin injection group, coloclysis group, plasma exchange group, combination group of coloclysis and plasma exchange in terms of treatment given and a control group was set up for each of the treatment group. In the intraperitoneal injection group, the prognosis and changes in clinical manifestations were observed in HF patients complicated with spontaneous peritonitis (SBP). In terlipressin injection group,HF patients complicated with hepatorenal syndrome (HRS) were observed for prognosis and changes in serum creatinine. In the combination group, the improvement in serum total bilirubin and prothrombin activity were observed.

Results Two weeks after intraperitoneal injection of antibiotics, the ease ratios of abdominal pain, pressure pain and rebound tenderness were 87.64%, 82.02% and 82.02% in the intraperitoneal injection group, respectively and the volume of ascites obviously decreased in 69 patients (77.53%). The survival rate in intraperitoneal injection group was significantly higher than in control group (P = 0.004). Four to eight days after the intravenous injection of terlipressin, the survival rate and the rate of serum creatinine decline of the treatment group were significantly higher than those in the control group (P = 0.003, P = 0.000). After 4 weeks of treatment, the ratio of clinical symptoms improvement (acratia, anorexia, abdominal distension, constipation) in coloclysis group were 60.27%, 57.53%, 91.78% and 94.52%, in plasma exchange group were 71.83%, 69.44%, 75% and 72.22%, and in combination group were 82.14%, 79.46%, 92.85% and 95.54%. The serum total bilirubin was decreased and the prothrombin activity increased and the differences were statistically significant as compared with control group (P = 0.000).

Conclusions The intraperitoneal injection of antibiotics, intravenous injection of terlipressin and combined treatment of coloclysis and plasma exchange were all effective for the treatment of HF and its complications.