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Open access

Yongqiang Sun, Dina Liu and Nan Wang

Abstract

Although user information disclosure behavior in the context of social network service(SNS) has been well studied in previous literature, there is a lack of understanding about user information withholding behavior. To fill this research gap, the present study assumes that there might be a three-way interaction among information sensitivity, prevention focus, and interdependent self-construal regarding information withholding. The proposed model is empirically tested through an online survey of 479 users in the context of WeChat, one of the most popular SNSs in China. The results of hierarchical regression analysis verify the three-way interaction that prevention focus positively moderates the relationship between information sensitivity and information withholding, and interdependent self-construal strengthens the moderating effect of prevention focus. Findings in light of theoretical and practical implications as well as limitations of the study are discussed.

Open access

Shixia Zhang, Jiantao Zhang, Nan Zhang, Jiao Shi and Hongbin Wang

Abstract

The objective of this study was to describe laparoscopic-assisted colopexy (LAC) technique, and compare the extent of the surgical trauma after LAC and open colopexy (OC) by examing postoperative serum values of C-reactive protein (CRP) in dogs. Twelve healthy mixed-breed dogs with body weight ranging from 15 to 25 kg were used. Two portal sites were used for LAC procedures. OC was performed by laparotomy on linea alba. Colopexy was accomplished in all dogs without major intraoperative and postoperative complications. A permanent adhesion between the colon and abdominal wall was observed. There were statistically significant differences in serum CRP levels between LAC and OC immediately after the procedure and 1 d post operation. LAC had a similar pexy effect to OC, but had fewer surgical trauma than OC in dogs.

Open access

Yue Wang, Liang Chen Qi, Nan Gao, Zhi Feng Han and Hai Xiang Yu

Abstract

Background: Usually children mistakenly swallow foreign bodies, and most objects are spontaneously discharged through the digestive tract without consequence. However, sometimes the objects can cause gastrointestinal perforation, with serious complications.

Objective: To report the case of a 26-year-old male patient, who mistakenly swallowed a bamboo chopstick 14 years ago. The chopstick eventually perforated the gastric fundus and left diaphragm, pierced the lower left lobe of the lung, and caused a lower left lung abscess.

Method: A thoracotomy was conducted to remove the foreign body and the lower left lobe of the lung, followed by a patch fundoplication.

Result: The object was removed and the patient’s lesions healed after surgery.

Conclusion: The ingestion of foreign bodies rarely causes serious problems, but we should be vigilant to the occurrence of complications, and close follow-up should be conducted. This follow-up should include confirmation that the foreign body has passed through the alimentary tract.

Open access

Ming-ming Wang, Su-nan Cui and Yan-xue Gong

Abstract

Objective To compare and analyze serum levels of procalcitonin (PCT) of children with viral and bacterial infection and probe into the importance of determining the level of serum PCT in the diagnosis of bacterial infection in order to provide evidences of the clinical use of antibiotics.

Methods A total of 85 cases of children with an average age of 8.9 years (10 months -12 years) were enrolled in this study, 53 cases were with viral infection and 32 cases with bacterial infection. We determined serum levels of PCT by semi-quantitative solid phase immunoassay, and the serum levels of PCT were divided into four grades as <0.5 μg / L, ≥ 0.5μg / L, ≥ 2.0μg / L and ≥ 10μg / L for x2 test and Ridit analysis.

Results The serum level of PCT of the group with bacterial infection were significantly higher than that of the group with viral infection (P < 0.001). The sensitivity of diagnosis of bacterial infection in children with determination of serum levels of PCT was 87.50% while the specificity was 92.13%, and positive predictive value was 73.68% while negative predictive value was 91.49%, and positive likelihood ratio was 4.65 while negative likelihood ratio was 0.15, and the diagnostic accuracy was 83.53%.

Conclusions Serum PCT is a bacterial sensitive marker of bacterial infection in children, and the determination of the level of serum PCT is helpful for the diagnosis of bacterial infection, which can also be a basis for the use of antibiotics.

Open access

Bin Li, Xiaomeng Cui, Lucan Zhao, Le Wang, Guoyong Xie and Nan Deng

Summary

Establishing a realistic gas flow velocity distribution inside a cigarette filter during smoking is important to understand filtration mechanisms of different mainstream smoke species and the overall effect of filter designs on mainstream smoke composition. In this paper, an experimental method is described which directly measures the gas pressure field inside a cellulose acetate filter during cigarette smoking. This was demonstrated by using 3R4F research reference cigarettes smoked under a 35 mL puff of 6 s duration. In addition, filter temperature measurements were also carried out at multiple locations within the filter. Both the temperature and pressure sensing locations were selected to match the radial and longitudinal directions of the cigarette filter. The temperature and pressure measurements were then used to calculate the velocity according to Darcy’s Law along the mainstream flow direction in the cigarette filter at each puff. The spatially resolved maps of temperature, pressure and flow velocity on a puff-by-puff basis provide useful insights into the dynamic filtration of smoke aerosol under the influence of the approaching burning coal and progressive accumulation of smoke particulate matter.

Open access

Xiaoxue Lian, Yan Li, Dongmin An, Yunling Zou, Qiong Wang and Nan Zhang

Abstract

In this study, we fabricated ZnO nanostructures using bamboo fibers as templates. The starting material used was zinc acetate, and the nanostructures were synthesized by soaking and calcining the bamboo fibers. The fabricated nanostructures were characterized using X-ray powder diffraction (XRD) analysis, scanning electron microscopy (SEM), and ultraviolet-visible spectrophotometry. The results showed that the size of the ZnO nanoparticles was approximately 20–100 nm. When the ZnO nanoparticles were used as the catalyst in the photodegradation of methyl orange, the dye degraded by 95.98 % in 80 min. The response and recovery times of a gas sensor based on the ZnO nanoparticles were 25 and 24 s, respectively, during the detection of C2H5OH in a concentration of 10 ppm at 270 °C.

Open access

Di Jin, Shengguo Zhao, Nan Zheng, Yves Beckers and Jiaqi Wang

Abstract

Urea is used as non-protein nitrogen in the rations of ruminants as an economical replacement for feed proteins. Urea transferred from the blood to the rumen is also an important source of nitrogen for rumen microbial growth. It is rapidly hydrolyzed by rumen bacterial urease to ammonia (NH3) and the NH3 is utilized for the synthesis of microbial proteins required to satisfy the protein requirements of ruminants. Urea has commonly become an accepted ingredient in the diets of ruminants. In recent decades, urea utilization in ruminants has been investigated by using traditional research methods. Recently, molecular biotechnologies have also been applied to analyze urea-degrading bacteria or urea nitrogen metabolism in ruminants. Combining traditional and molecular approaches, we can retrieve better information and understanding related to the mechanisms of urea metabolism in ruminants. This review focuses on urea utilization in ruminants and its regulation by rumen bacterial urease in the host. The accumulated research provides foundations for proposing further new strategies to improve the efficiency of urea utilization in ruminants.

Open access

Ren-Nan Feng, Cheng Wang, Chang-Hao Sun, Fu-Chuan Guo, Chen Zhao and Ying Li

Abstract

Background: Visceral adipose tissue-derived serine protease inhibitor (vaspin) is a novel adipocytokine. Several studies have indicated that vaspin may exert an important role in the development of metabolic disorders.

Objective: Evaluate serum vaspin and its relation to clinical parameters in newly and previously diagnosed Chinese type 2 diabetes mellitus (T2DM) females as a case-control study.

Materials and methods: One hundred twenty female participants (newly and previously diagnosed T2DM patients) were recruited from an affiliated hospital of Harbin Medical University. Sixty healthy female volunteers from various communities were included as controls. Anthropometric parameters, serum fasting blood glucose, fasting insulin, lipid profile, HbA1c, and vaspin were measured in each participant.

Results: Serum vaspin levels were significantly lower in previously diagnosed T2DM patients (0.51±0.29 ng/mL) than in newly diagnosed T2DM patients (0.62±0.28 ng/mL) and healthy controls (0.69±0.31 ng/mL). However, there was no difference in serum vaspin between newly diagnosed T2DM patients and healthy controls. In multiple linear regression analysis, serum vaspin was significantly and positively associated with HbA1c in both newly and previously diagnosed T2DM patients, negatively associated with homeostasis model assessment of insulin resistance in previously diagnosed patients, and positively correlated with age and body mass index in healthy controls.

Conclusion: Serum vaspin was significantly lower in previously diagnosed T2DM patients than in newly diagnosed T2DM patients and healthy controls. Serum vaspin might be a predictor of poor glucose control and insulin resistance in T2DM.

Open access

Nan Hu, Laura Cerviño, Paul Segars, John Lewis, Jinlu Shan, Steve Jiang, Xiaolin Zheng and Ge Wang

Abstract

Background. With the rapidly increasing application of adaptive radiotherapy, large datasets of organ geometries based on the patient’s anatomy are desired to support clinical application or research work, such as image segmentation, re-planning, and organ deformation analysis. Sometimes only limited datasets are available in clinical practice. In this study, we propose a new method to generate large datasets of organ geometries to be utilized in adaptive radiotherapy.

Methods. Given a training dataset of organ shapes derived from daily cone-beam CT, we align them into a common coordinate frame and select one of the training surfaces as reference surface. A statistical shape model of organs was constructed, based on the establishment of point correspondence between surfaces and non-uniform rational B-spline (NURBS) representation. A principal component analysis is performed on the sampled surface points to capture the major variation modes of each organ.

Results. A set of principal components and their respective coefficients, which represent organ surface deformation, were obtained, and a statistical analysis of the coefficients was performed. New sets of statistically equivalent coefficients can be constructed and assigned to the principal components, resulting in a larger geometry dataset for the patient’s organs.

Conclusions. These generated organ geometries are realistic and statistically representative

Open access

Xi-Lin Liu, Xiao-Li Feng, Guang-Ming Wang, Bin-Bin Gong, Waqas Ahmad, Nan-Nan Liu, Yuan-Yuan Zhang, Li Yang, Hong-Lin Ren and Shu-Sen Cui

Abstract

Introduction: The functions and mechanisms of prion proteins (PrPC) are currently unknown, but most experts believe that deformed or pathogenic prion proteins (PrPSc) originate from PrPC, and that there may be plural main sites for the conversion of normal PrPC into PrPSc. In order to better understand the mechanism of PrPC transformation to PrPSc, the most important step is to determine the replacement or substitution site.

Material and Methods: BALB/c mice were challenged with prion RML strain and from 90 days post-challenge (dpc) mice were sacrificed weekly until all of them had been at 160 dpc. The ultra-structure and pathological changes of the brain of experimental mice were observed and recorded by transmission electron microscopy.

Results: There were a large number of pathogen-like particles aggregated in the myelin sheath of the brain nerves, followed by delamination, hyperplasia, swelling, disintegration, phagocytic vacuolation, and other pathological lesions in the myelin sheath. The aggregated particles did not overflow from the myelin in unstained samples. The phenomenon of particle aggregation persisted all through the disease course, and was the earliest observed pathological change.

Conclusion: It was deduced that the myelin sheath and lipid rafts in brain nerves, including axons and dendrites, were the main sites for the conversion of PrPC to PrPSc, and the PrPSc should be formed directly by the conversion of protein conformation without the involvement of nucleic acids.