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Objective To investigate the prevalence of zika virus (ZIKV), dengue virus (DENV) and chikungunya virus (CHIKV) infections in blood donors in Kunming, China. Methods A total of 10 662 samples from blood donors in Kunming from August 2022 to October 2023 were randomly collected, and ZIKV RNA, DENV RNA and CHIKV RNA were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction(RT-qPCR). Results Effective test results were obtained from 10 554 samples, and no positive case of ZIKV RNA, DENV RNA and CHIKV RNA was found in this investigation. Conclusion The risk of ZIKV, DENV and CHIKV infections among blood donors in Kunming is low, and there is no immediate need for routine screening for these viruses among blood donors in this region.

With the continuous development of the Internet industry, the function and technology of instant translation software can be continuously improved. This paper takes the machine translation model based on neural networks as the research basis and proposes a translation model suitable for the use of English instant translation software. Through word vector transformation, natural language is transformed into digitized symbols, and the n -gram model is used to improve the fluency of the processing. Using the neural probabilistic language model, the conditional probability of language processing is calculated. Introduce a recurrent neural network and optimize and adjust it based on the original model. Design the model framework for instant translation software for a series of operations, such as language signal processing. The case study revealed the factors that influenced users’ experience of using the software and their expectations of the instant translation software. The results show that the OR estimate of users’ satisfaction is 3.1655, and a one-unit increase in satisfaction will increase the advantage of instant translation software by 3.17 times. The error rate of translation software, as well as the learning cycle, have different degrees of influence on the advantage of the software. The period 2001-2022 was chosen as the study period, and the number of published patents for instant translation software research was examined. The overall trend during the study period showed a gradual increase. The number of patent publications increased by 40.9% to 62 in 2017, compared to the previous year. Instant translation software's future development trend is positive.

Objective To screen non-invasive indicators for predicting poor response to ursodeoxycholic acid in patients with primary biliary cholangitis（PBC）and establish a logistic regression model. Methods A total of 106 patients with PBC were selected in the modeling group. Clinical data of PBC patients before and after receiving 1 year ursodeoxycholic acid therapy were retrospectively analyzed. According to ParisⅡcriteria， all patients were divided into two groups： poor response group （n = 38） and complete response group （n = 68）. The general condition， laboratory indicators and ultrasound examination results of the patients were analyzed by non-conditional logistic regression model before and after treatment. Non-invasive indicators for predicting poor response to ursodeoxycholic acid were screened， and the regression model was established. To validate this model， 47 patients with PBC who visited Ditan Hospital for the first time were selected in the validation group， and were treated with ursodeoxycholic acid for 1 year. Results Univariate analysis showed that in the modeling group， there were significant differences in cholinesterase， alkaline phosphatase， direct bilirubin， γ-glutamyltranspeptidase， globulin， total triglyceride， total cholesterol， low-density lipoprotein cholesterol， erythrocyte sedimentation rate， CD4+T cell count and CD8+T cell count between the poor response and complete response groups before treatment （all P < 0.05）. Multivariate unconditional logistic analysis showed that cholinesterase， alkaline phosphatase and direct bilirubin before treatment were effective predictors of poor response. The regression model was： Y = 0.000339× cholinesterase （U/L） +2.227292× （whether the ALP is lower than 2 times of normalupper limit； 1= yes， 2= no） +0.024151×DBIL （μmol/L）. The sensitivity and specificity of the model for predicting poor response were 88.6% and 84.8%， respectively. In this validation cohort， the area under the receiver operating characteristic curve was 0.81（95% CI 0.69-0.94）. Conclusion Cholinesterase， alkaline phosphatase and direct bilirubin before treatment can predict poor response to ursodeoxycholic acid in PBC patients.

【Background and objective】 Sufficient sunlight and large diurnal temperature variation in Huaian-Xuanhua Basin in Zhangjiakou City of Hebei province makes it an ideal area for growing wine grape, but this is hindered by its scarce water resource and pore soil quality. Traditional irrigation and fertilization not only waste precious water and fertilizers but also compromise grape yield and quality. Improving use efficiency of irrigation water and fertilizers is hence essential to sustaining wine grape industry in this region. The purpose of this paper is to investigate experimentally how to achieve this via drip fertigation. 【Method】 We used 10- year cabernet sauvignon as the model plant. The field experiment was conducted in 2019 at a grape vineyard in Zhangjiakou. There were three irrigation treatments: sufficient irrigation (HW), moderate deficit irrigation using 80% of the water in HW (MW), and severe deficit irrigation using 60% of the water in HW (LW). For each treatment, we measured the sap flow from May to October in the stems, fruit yield and quality, and water use efficiency of the grapes, from which we analysed the relationship between sap flow and environmental factors. 【Result】 The sap flow showed a circadian rhythm; seasonally, it increased first and then fell as time elapsed. The impact of irrigation amount on sap flow was ranked in the order of HW > MW > LW. It was found that the sap flow rate was positively correlated to solar radiation and air temperature, while negatively correlated to air relative humidity. Multiple regression revealed the sap flow rate varied with air temperature, solar radiation, air relative humidity and wind speed, all at significant level, especially in MW. The maximum fruit yield was 10 736.68 kg/hm2 achieved in MW, and the least was 9 900.93 kg/hm2 due to water deficit in LW. Irrigation amount had a significant effect on irrigation water use efficiency (IWUE) (P

A kind of underground adaptive positioning algorithm based on PSO-BP neural network was proposed. In view of the problem that traditional positioning algorithm based on ranging model is sensitive to coal mine environment disturbance and ranging error is large, a fingerprint matching positioning model is selected for positioning. In view of the problem that strong time-varying nature of coal mine environment is easy to increase matching error between the fingerprint information collected in real time and the static fingerprint database information established in offline phase, the beacon node is used as calibration node to better reflect the condition of reference point changes with environment, and avoid adding additional calibration nodes. The dynamic compensation method is used to correct the fingerprint data of the target node in real time without increasing the hardware cost, which solves the problem of poor adaptation of the fingerprint matching positioning model. At the matching positioning stage, PSO is used to optimize weight of BP neural network to accelerate convergence of BP neural network and improve learning speed. The experimental results show that the algorithm is more adapted to the coal mine environment varies with time, and meets the requirement of adaptive underground positioning.

The high power transfer case as a key component of a multi-axis super-heavy chassis transmission system,with the characteristics of large torque,high speed,and large temperature difference,rely on splash lubrication and natural air cooling has been unable to meet the need of the chassis for high mobility,high through off-road and extreme ambient temperature. It is necessary to use the forced lubrication system to lubricate the internal hot spots of the transfer case,especially the bearing position. Therefore,the power thermal energy model of the hotspots of the transmission parts is built first,through the heat balance conditions,the flow demand of the lubrication point and the overall are estimated,and then a hydraulic simulation analysis model is established,the matching lubrication system piping is designed. Aiming at the problem of the natural air cooling can’t achieve the system thermal balance requirements in the great power of the transmission system,by calculating the surface wind speed and heat dissipation surface,the heat dissipation capacity of the transfer case itself is evaluated,the external air-cooled radiator and fan are matched according to the heat dissipation requirement.Finally,through the bench and running vehicle test,the design of the high power transfer case forced lubrication system to meet a multi-axis super-heavy chassis of the use of the requirements is verified.

Based on the theory of dimension chain,the dimension chain compute with extremum method and probability method is researched. It defines that compute method determined by the number of composition loops,the real statistical data and the statistical process control ability can be used to optimize the dimension chain. Usually,the structure of gearbox is complicated,but the accumulative error must be controlled in a minor range. That method can avoid severe dimension tolerances of components and parts in the design of gearbox,meanwhile products can be manufactured reliably and economically.

In the multi-axis super-heavy-duty test platform,the high-power transfer case has the problem of broken teeth during fatigue endurance. The comprehensive analysis is carried out on the failure gears,the causes of gear damage,such as gear strength,shaft and box stiffness,gear tooth profile and tooth orientation precision,surface heat treatment,etc. are analyzed one by one,and finally it is positioned as the gear tooth surface grinding burns,resulting in reduced hardness of the tooth surface,contact fatigue strength decreased,the occurrence of premature failure damage. In the improvement work,the grinding process of the gear tooth surface is modified,and 100% grinding burn monitoring is added. The improved high-power transfer case passed the fatigue endurance test.

The inter- axle differentials as a core component of power transfer cases is used to achieve the distribution of chassis power and meet the needs of working conditions of vehicle cornering and climbing,which has played a key role in ensuring the reliability of the vehicle power transmission. By using the two- stage optimization method,the inter- axle differential planetary wheel structure optimized design is carried out,on the one hand to ensure the strength of the structure,on the other hand to reduce the quality of products to meet the requirements of the vehicle light weight and high maneuverability. By the checking of classic strength calculation and finite element method,it shows that the optimization program could meet the requirements of both high torque and high- reliability design of the planetary gear inter- axle differential of multi- axis ultra- heavy-duty chassis large power transfer case.