Electrical resistivity-based study of self-sensing properties for shape memory alloy-actuated artificial muscle.

Shape memory alloy (SMA) has great potential to develop light and compact artificial muscle (AM) due to its muscle-like high power-to-weight ratio, flexibility and silent operation properties. In this paper, SMA self-sensing properties are explored and modeled in depth to imitate the integrated muscle-like functions of actuating and self-sensing for SMA-AM based on the investigation of SMA electrical resistivity (ER). Firstly, an ER transformation kinetics model is proposed based on the simulation of SMA differential scanning calorimetry (DSC) curves. Then a series of thermal-electrical-mechanical experiments are carried out to verify the validity of the ER model, whereby the SMA-AM self-sensing function is well established under different stress conditions. Finally the self-sensing capability is further demonstrated by its application to a novel SMA-AM-actuated active ankle-foot orthosis (AAFO).

[Virus spectrum features of adult influenza-like fever in outpatients].

OBJECTIVE: To analyze the results of detection on respiratory virus of influenza-like illness ( ILI ) in Beijing from June 2010 to February 2012 and understand the virus spectrum of adult influenza-like fever. METHODS: A total of 502 swabs were collected and 279 throat swabs tested for 12 respiratory viruses with multiplex reverse transcription-polymerase chain reaction (RT-PCR). And 413 swabs were tested for pH1N1 by virus isolation influenza viruses. And the data were statistically analyzed. RESULTS: One or two viruses were detected in 26.9% (75/279) of the samples. Influenza A virus (FLU-A) accounted for 85.3% of positive samples and 22.9% (64/279) of ILI tested. The positive rate of other viruses was less than 3.0 %. The positive rates among the following subtypes were: 2.7% (11/413) for pH1N1, 2.4% (10/413) for H3 and 6.5% (27/413) for FLU-B. FLU-A was the predominant virus during the 2010-2011 influenza season and the positive rate peaked in January 2011 in Beijing and north China. FLU-B was the primary virus during the 2011-2012 influenza season and the positive rate peaked in January and February 2012. There was a significant reduction in the incidence of ILI in 2010 and 2011 when compared with 2009. During the 2009-2012 influenza seasons, the incidence peaked in December 2009, January 2011 and January and February 2012 in Beijing. CONCLUSIONS: Exposure to pH1N1 had no impact on typical influenza seasonal peaks. Influenza virus was the predominant virus of adult influenza-like fever cases after the pandemic period of influenza A (H1N1) 2009 and the positive rate peaked in January and February during the 2009-2012 influenza seasons.

[Etiological study on sporadic viral gastroenteritis among adult in Beijing].

OBJECTIVE: To understand the infection and epidemiology of norovirus and rotavirus and enteral adenovirus among adult with sporadic viral gastroenteritis in Beijing and provide theoretical basis for clinical prevention and control. METHODS: Stool specimens were collected from all 312 sporadic outpatient among adult with non-cholera watery diarrhea in Infectious Disease Department of Peking University People's Hospital 2005-2006. PAGE were used for detection of rotavirus RNA in stool specimens; R-Biopharm RIDASCREEN norovirus and RIDASCREEN adenovirus were used for detection of norovirus and adenovirus. RESULTS: Rotavirus RNA was not present in all 312 stool specimens; Norovirus was present in 17.6% (22/125) and in 32.4% (11/34) in October; Adenovirus was present in 3.3% (3/92); Mixed infections of norovirus and adenovirus was present in 1 stool specimen. CONCLUSIONS: Norovirus is more common etiologic agents of sporadic acute viral gastroenteritis among adult in Beijing, The infection peak of norovirus is in autumn. Maybe the infection of rotavirus is few.

[Screening analysis of irregular antibodies from random donor population in Shaoguan area].

The study was purposed to analyze the frequency and distribution of irregular antibodies in Shaoguan area. Screening 15 033 random donor antibodies in Shaoguan area by screening cells, polybrene and antiglobulin tests. The results indicated that the irregular antibodies were found in 42 samples. The frequency of irregular antibodies in female was higher than that in male (P < 0.001), and Rh blood group antibodies such as anti-D, anti-E, and anti-Ec C were common (47.6%). 2 samples of Le antibodies were failed to be found by polybrene test. 2 samples of irregular antibodies with titer 2 were undiscovered by screening test of 10 pooled samples. In conclusion, because of irregular antibodies resulting in hemolytic transfusion reaction, the investigation of frequency and distribution of irregular antibodies is very important for safe transfusion. Antibody screening must be done for female donors, and especially for massive plasma transfusion of patients with severe and dangerous illness and infants so as to ensure safety.

[Study on blood ABO typing in patients with autoimmune hemolytic anemia].

To explore effect of autoantibody on identification of ABO and RhD blood group, the blood samples of 38 patients with autoimmune hemolytic anemia (AIHA) were identified by routine typing and typing after chloroquine elution test as well as PCR. The results showed that out of 38 patients with AIHA, 11 cases (31.6%) of ABO blood group were difficulty typed, indirect antiglobulin test were positive, and contradiction between cells typing and sera typing were observed. 1 case of RhD(-) was mistyped as RhD(+) and anti-D was found in its serum. The blood group of these cases were typed correctly by chloroquine elution test. It is concluded that blood group identification of patients with AIHA can be interfered by autoantibody, and the correct typing for blood group of these patients may be determined by using combination of several methods to ensure safe transfusion.