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Ultrasonic signals will be generated when partial discharge occurs in internal insulation faults in large oil immersed power transformers: because the ultrasonic signal has strong anti-interference ability and has no direct electromagnetic contact with the equipment, it is widely used in transformer fault detection and positioning. In this paper, the finite element method (FEM) is used to simulate the ultrasonic signal in a 35 kV power transformer. The influence of transformer case on ultrasonic signal propagation is considered, and the propagation law of the ultrasonic signal inside the transformer is obtained. Fabry–Perot (F–P) fibre acoustic sensors with a centre frequency of 28 kHz were fabricated. A partial discharge detection test was carried out in a 35 kV transformer winding model using the F–P sensors. The test results show that the ultrasonic waveform detected by the F–P sensors are in good agreement with the simulation results, and the propagation of the ultrasonic wave inside the transformer is verified. It lays a foundation for detecting and locating PDs in power transformer by F–P acoustic sensors.

This paper proposes a subsystem-based structure evolution algorithm for stable IIR digital filter design. The method designs the IIR digital filter through optimizing the filter structure. A filter structure is defined as the connection of the subsystems. A subsystem is a 2-order IIR digital structure with uncertain parameters. Subsystems are randomly connected with the constraints of no feedback branches between subsystems. The subsystem’s parameters and the connections between subsystems are optimized by evolutionary algorithms. An adaptive multiple-elites-guided composite differential evolution algorithm (AMECoDEs) is used to optimize this problem. Four classic types of filters, lowpass, highpass, bandpass and bandstop filters are designed. Five state-of-the-art evolutionary algorithms are compared. The simulation results show that AMECoDEs holds the first place on comprehensive performance and convergence rate. At the same time, the poles of filters all reside within the unit circle, which validates the stability of the IIR digital filters.

Acetic acid bacteria (AAB) can spoil food. Acetobacter aceti as a core subgroup of AAB is usually isolated from yogurt. A. aceti should be timely and effectively detected to prevent yogurt contamination. The present study focused on A. aceti to establish an assay that can be performed to detect AAB in yogurt. LAMP, PCR, and real-time PCR were applied and compared for detecting A. aceti from pure culture and artificially contaminated yogurt samples. In pure culture, LAMP showed the highest detection sensitivity with 10−1 CFU/mL. For yogurt samples, the sensitivity limit of LAMP was 102 CFU/mL, which was lower than that of real-time PCR (101 CFU/mL). The results indicated that these methods could be quickly and efficiently applied to detect A. aceti. As LAMP technology has low cost and high detection efficiency, it can potentially be applied for detecting A. aceti in production and quality control programs of yogurt.

Rapid production of doubled haploids (DHs) through isolated microspore culture is an important and promising method for genetic study of alfalfa. To induce embryogenesis in alfalfa, isolated microspores were submitted to abiotic stresses during their initial culture, in order to stimulate them to form embryos and plantlets. ‘Baoding’ and ‘Zhongmu No 1’ alfalfa cultivars supported reproducible and reliable proliferation response irrespective of any stress treatment of microspores. The microspore developmental stage for isolated microspore culture was studied and we found that uninucleate microspores were best to initiate culture. Exposure of microspores to appropriate low temperature or heat shock stresses were able to increase the efficiency of embryogenesis. The most effective low-temperature treatment was 4 °C for 24 h and the frequency of plantlets induction was 20.0%. The most effective heat shock treatment was 32 °C for 2 d and the frequency of plantlets induction was 14.17%. The analysis of ploidy level performed by flow cytometer revealed that the majority of 278 regenerated plantlets were haploid (65.83%) or doubled haploid (33.81%). This is the first report of haploid production in alfalfa through isolated microspore culture.

MPEG was modified with 1,1'-carbonyldiimidazole, then the activated MPEG reacted with primary amino groups of chitosan. Synthesize the graft copolymer of chitosan and polyethylene glycol in two steps. The structure of the copolymer was characterized by FT-IR and 1H-NMR. It agrees with the PEG content of classical stealth nanoparticles materials. The X-ray diffraction and DSC analysis proved that the crystallinity of the copolymer increased. It is a promising material for the stealth nanoparticles. It is a potential new carrier for the drug delivery systems of long-circulation and solid carcinoma.

Epidemiological studies on the association between SULT1A1 codon 213 polymorphism and breast cancer risk are inconclusive. In order to derive a more precise estimation of the association, a meta-analysis was conducted in this article. Sixteen studies including 9,881 cases and 13,564 controls were collected for SULT1A1 codon 213 polymorphism by searching the databases of Medline, PubMed, Embase, and ISI Web of Knowledge. The strength of association between SULT1A1 codon 213 polymorphism and breast cancer susceptibility was assessed by calculating crude ORs with 95% CIs. When all the 21 studies were pooled into the meta-analysis, there was no evidence for significant association between SULT1A1 codon 213 polymorphism and breast cancer susceptibility (for Arg/Arg versus Arg/His: OR = 0.999, 95% CI = 0.941-1.061; for Arg/Arg versus His/His: OR = 1.121, 95% CI = 1.013-1.242; for dominant model: OR = 1.128, 95% CI = 1.01-1.26; for recessive model: OR = 1.151, 95% CI = 0.950-1.394). In the subgroup analysis by the source of controls, significant increased risk was found for hospital-based studies (for Arg/Arg versus Arg/His: OR = 1.173, 95% CI = 1.000-1.376; for Arg/Arg versus His/His: OR = 1.600, 95% CI = 1.134-2.256; for dominant model: OR = 1.269, 95% CI = 1.134-2.256; for recessive model: OR = 1.664, 95% CI = 1.070-2.588). In summary, the meta-analysis suggests that SULT1A1 codon 213 polymorphism may be associated with the hospital-based studies. However, large number of samples and representative hospital-based studies with homogeneous breast cancer patients and well-matched controls are warranted to confirm this finding.

Chronic pharyngitis, a chronic inflammation of the pharyngeal mucous membrane and submucous lymphoid tissues, is often caused by unsatisfactory treatment of acute pharyngitis or repeated occurrences of upper respiratory tract infection and is related to a high-dust environment. Traditional herbal pharmacotherapy is well known for combining plant species to create complex phytochemical mixtures in the attempt to ameliorate pathophysiological processes. The aim of current study is to investigate the effect of immunoregulation and anti-inflammation with the traditional Chinese medicine (TCM) "Li-Yan Zhi-Ke Granule" in rats. Determination of serum hemolysin and the carbon particle clearance test were performed. The results demonstrate that administration of the TCM "Li-Yan Zhi-Ke Granule" may improve the effect of phagocytosis by mononuclear macrophages and immune function in rats, and may also increase the immunoregulatory and anti-inflammatory responses of rats with chronic pharyngitis. This traditional drug could relieve the symptoms of sore throat and cough in rats with chronic pharyngitis.