Hepatitis E virus as an emerging zoonotic pathogen

Hepatitis E outbreaks are a serious public health concern in developing countries. The disease causes acute infections, primarily in young adults. The mortality rate is approximately 2%; however, it can exceed 20% in pregnant women in some regions in India. The causative agent, hepatitis E virus (HEV), has been isolated from several animal species, including pigs. HEV genotypes 3 and 4 have been isolated from both humans and animals, and are recognized as zoonotic pathogens. Seroprevalence studies in animals and humans indirectly suggest that HEV infections occur worldwide. The virus is primarily transmitted to humans via undercooked animal meats in developed countries. Moreover, transfusion- and transplantation-mediated HEV infections have recently been reported. This review summarizes the general characteristics of hepatitis E, HEV infection status in animals and humans, the zoonotic transmission modes of HEV, and HEV vaccine development status.     

Blood, Bull Terriers and Babesiosis: further evidence for direct transmission of Babesia gibsoni in dogs

This study reports on the epidemiology of Babesia gibsoni in American Pit Bull Terriers living in a region of western Victoria in southern Australia. Both American Pit Bull Terriers (n = 100) and other dog breeds (n = 51) were screened for B gibsoni using immunofluorescent antibody testing (IFAT) and/or polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). A questionnaire was also completed by each dog owner, ascertaining the husbandry and habits of the dogs sampled. Fourteen dogs were positive for B gibsoni using IFAT and/or PCR-RFLP and all were American Pit Bull Terriers. Dogs that were male and/or had been bitten by or were biters of other American Pit Bull Terriers were more likely to be B gibsoni positive, thus suggesting that blood-to-blood transmission contributes to the spread of this disease between dogs.     

Purinergic control of the quail rectum: modulation of adenosine 5'-triphosphate-mediated contraction with acetylcholine

Electrical field stimulation (EFS) induces frequency-dependent contractions of the longitudinal muscle of isolated quail rectum which were sensitive to tetrodotoxin. The aim of the present study was to investigate whether purinergic neurons are implicated in the response to nerve stimulation. The shape of the EFS-induced contractile response was different depending on stimulus frequency; low frequencies (0.5-2 Hz) induced fast monophasic contractions with a small subsequent relaxation; whereas higher frequencies (5-50 Hz) induced biphasic contractile response that comprised fast initial component (as in case of low frequency) and a slow delayed contractile component in addition to the relaxation that follows the fast contractile component. Prior application of atropine (10 microM) completely abolished the slow delayed component but significantly enhanced the fast initial contractile component. Physostigmine (1-10 microM) significantly enhanced the slow delayed component with an inhibitory effect on the initial fast component. The nonspecific purinergic receptor antagonist, suramin (100-500 microM) significantly inhibited the fast initial contractile component with no significant effect on the slow delayed one. Complete blockade of the fast component was achieved by prior application of a combination consisted of suramin (50 microM) and pyridoxicalphosphate-6-azophenyl 2',4'-disulphonic acid tetrasodium (PPADS; 10 microM). Exogenous applications of adenosine 5'-triphosphate and acetylcholine (10 microM each), produced contractile responses that mimicked those induced by EFS. These data suggest that ATP is the main noncholinergic excitatory transmitter controlling the contractile activity of the quail rectum; and that its action could be modulated by acetylcholine.     

基于MaxEnt模型预测梨火疫病菌的潜在地理分布

为探究梨火疫病菌解淀粉欧文氏菌Erwinia amylovora在全球的潜在地理分布,基于其全球分布数据和筛选得到的环境变量,利用MaxEnt模型对其在当前气候和未来气候条件下的潜在地理分布进行预测,并利用刀切法和皮尔逊相关性分析法筛选对梨火疫病菌分布有重要影响的环境变量。结果显示,对梨火疫病菌分布有重要影响的环境变量包括2月平均最高温度、1月平均降水量、7月平均最低温度、温度变化方差、昼夜温差月均值和7月平均降水量,表明春季和夏季的温度和降水对梨火疫病菌的分布有较大影响。在当前气候条件下,梨火疫病菌在全球的适生区分布较广,适生区总面积达到5.58×10⁷ km²,且高适生区主要分布在北美洲沿海地区、地中海沿岸和亚洲中部及东部的部分地区;梨火疫病菌在我国的适生区总面积为7.36×10⁶ km²,占全国陆地总面积的76.70%;在未来气候SSP126和SSP585情景下,梨火疫病菌在全球的适生区总面积分别为5.52×10⁷ km²和5.24×10⁷ km²。表明梨火疫病菌对我国大部分地区有潜在威胁,应加强监测与防控。     

Electro-circuit Design About the Data Acquisition and Wireless Transmission System Based on High-speed SCM

Considering the difficult of acquiring and transmission the signal from the moving equipment, a new fault diagnosis monitoring system is presented. The system acquires the state signal from the moving equipment by data acquisition module that based in W77E58 high-speed SCM, and transmits the data fast by wireless mode. The signal data can be use for fault diagnosis and precise analysis. The system has the ability for acquiring abundance of data with a high speed, the ability for high accuracy data conversion, and has a function of programme controlling gain and programme controlling low-pass filtering. The successful application of this system on the vibration monitor about the material-transporting bogie in an iron works of a domestic steel enterprise proves the stability and credibility about the design project, also testifies its practical value and versatility.     

Transmission Congestion Management Based on Power Influence Coefficient

Basing eliminating on the idea that the generator who has the most influence on the power flow of line is mostly in favor of transmission congestion, the model of congestion management with the object of minimizing adjustments of bufions varied with generation outputs is proposed. It can eliminate the congestion effectively by judging the generators who should be adjusted and the amounts of adjustment. The test on IEEE-RTS24 buses system and other practical systems show that the proposed method is effective.     

VARIABLE DAMP STRUCTURAL RELIABILITY DUE TO MULTIPLE RANDOM EXCITATIONS AND SENSETIVITY ANALYSIS

The reliability of random vibration is discussed,and then by using the first order perturbation method and with the aid of relation of the systemic response function to the first order sensetivity of variable damp parameter, the rate of change of structural reliability indication is derived, therefore the constraint equation to guarantee reliability for the structural optimization design is proved and the satisfactory result is obtained,test and the practicability of this method is tested.     

Influence of HVDC System on the Shaft of Hydro-generator Unit

Widely concerns of the influence of the HVDC system on the Three Gorges power station have been shown so far. Based on the understanding of the mechanism of the non-characteristic harmonics introduced by HVDC system, the influence of interharmonics on the shaft of hydro-generator unit is studied. A MATLAB simulation model for the Three Gorges hybrid AC and DC transmission system with considering the effect of generator-unit shaft is established. Through time-domain simulation, the influence of the minor-associated component of interharmonics on the generator-unit shaft is analyzed, which arise from the asynchronous operation of the HVDC system. Also, the complex torque coefficient method in frequency-domain is used to analyze this problem. Same conclusions can be drawn from the results of timedomain and frequency-domain analyses.