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Hepatitis E virus （HEV） is a universal foodborne pathogen that infects swine， deer， rabbits， camels， and other animals. Direct contact with infected pigs and other animals or consumption of contaminated food （uncooked or undercooked） poses a risk of HEV infection in humans. This article summarizes the etiology and epidemiology of HEV， its prevalence in various animal species， and the contamination of meat and meat products， the aquatic environment， seafood， vegetables， and other crops. Therefore， people can better understand the risk of foodborne HEV transmission and provide a scientific basis for preventing and controlling its prevalence.

Aiming to address the problem of low classification accuracy caused by the different shapes of meniscus tears in the computer-aided diagnosis (CAD) system for meniscus, a multidimensional information fusion network (MDIFNet) model for menissus tear classification was proposed. Firstly, a convolutional neural network (CNN) architecture consisting of four sub-networks was used to obtain meniscus feature information from different perspectives and dimensions. Simultaneously, multi-scale attention mechanism was proposed to enrich fine-grained features. Finally, a multi kernel model based on support vector machines (SVM) was constructed as the final classifier. The experimental results on the MRNet dataset show that the proposed method has a meniscal tear classification accuracy of 0.782, which has promotion compared to the existing state-of-the-art meniscus tear classification methods based on deep learning.

Forests cover four billion hectares (31%) of the Earth’s landmass and contain over 75% of all carbon in vegetation. They provide renewable raw materials and natural amenities, protect land and water resources, harbor biological diversity, and mitigate climate change. However, due to less precipitation, the forest coverage rate is only 5.86% in Northwest China. The forests in these arid areas are mainly distributed in alpine areas, which play a key role in runoff regulation and ensure the ecological and economic development of the middle and lower reaches of the inland basins. In the past several decades, China had experienced large-scale deforestation and reforestation. What were the changes of the few forest areas and growing stock in arid Northwest China? Has forest quality been restored? Changes of that had been analyzed in this article. The results showed that the forest area and growing stock decreased greatly from the 1950s to 1970s; the artificial forest area increased clearly; the natural forest area stabilized from the 1980s, growing stock of forest per unit area was still lower than that in the 1950s; and the forest quality had not yet been restored. Results of the analysis of influencing factors showed that the policy-led human activities in different periods were the efficient cause of forest changes in Northwest China. With the development of forestry science, more and more attention has been paid to forest ecological restoration. “Three-North Shelter Forest Program (TNSFP)” in 1978 had made great progress on forest areas by afforestation, and the ecological benefits and economic benefits also increased remarkably owing to the increase in the artificial forest area. In recent years, great progress on forest areas has been made by afforestation, and the forests also contribute significantly to the ecology and economy. However, large-scale afforestation in the Loess Plateau had caused a phenomenon of large investment and little effect on water conservation in some afforestation areas, which showed that afforestation initiated under different polices, which were not always scientifically based, resulted in unintended consequences. Clear ecological principles should be used to ensure best environmental and forest ecology outcomes.

[Objectives] This paper presents a numerical study of the air environment comfort in a four-person accommodation cabin of a ship in order to analyze the influence of different air supply schemes on the air environment.[Methods] The evaluating indicators of airflow organization are analyzed by CFD and a simulation of the air supply velocity,temperature,relative humidity,PMV and CO2 concentration of the fluid-domain model under summer design conditions is conducted. Through comparisons with the simulation results of different air supply schemes,the influence of the air supply angle,temperature and rate on the thermal comfort and air quality are studied.[Results] The simulation results show that when the air supply angle is 30 to 45 degrees,it has little influence. Although reducing the air supply temperature and rate leads to a lower relative humidity and higher CO2 concentration,it can successfully meet the design requirements and improve thermal comfort when considering the evaluation indexes of airflow organization.[Conclusions] These research results can provide certain guiding references for the air supply layout in the accommodation cabins of ships.

Flexible strain sensors from biaxially stretched carbon nanotubes (CNTs)/polydimethylsiloxane (PDMS) nanocomposites are fabricated in this study. It is shown that biaxial stretching promotes the homogeneous distribution and alignment of CNTs in the stretching plane, improving the sensing performance of the strain sensors. The optimized stretching ratios (SRs) of CNT/PDMS nanocomposites are determined. Compared to an unstretched CNT/PDMS-1.0 sensor (gauge factor [GF] value = 0.73, detectable range from 0 to 60%), the 1.5 wt% CNT/PDMS-1.5 sensor (SR = 1.5) exhibits enhanced strain sensitivity (GF = 2.8), a wider detectable range (0-370%) and better performance stability. The GF values of CNT/PDMS-2.0 and CNT/PDMS-2.5 sensors with SRs of 2.0 and 2.5, respectively, were 1.18 and 1.06, respectively, due to more significant conductive network reconstruction in the process of applying strain, leading to a decreasing GF. The possibility of sensors in the application of wearable electronic components is also demonstrated. The sensor shows a clear and stable signal output when different strain modes are applied, such as tensile, compressive, bending, and twisting. KEYWORDS CNTs, flexible strain sensor, PDMS, simultaneous biaxial stretching, orcid.org/0000-0002-8714-6576 orcid.org/0000-0001-7355-8759 orcid.org/0000-0002-1148-777X orcid.org/0000-0001-6106-1868 1 | INTRODUCTION With the development of new materials and the great progress of manufacturing technology, flexible and stretchable electronic products, such as stretchable conductors, transistors, [...]