In lately December 2019, a novel coronavirus (SARS‐CoV‐2) outbreak occurred in Wuhan, PR China. It is a high contagious virus that has threatened human health worldwide. SARS‐CoV‐2 infection, termed COVID‐19, causes rapidly developing lung lesions that can lead to multiple organ failure in a short period. Whenever a novel virus emerges, reproductive risk assessments should be performed after infection. In this review, we show that male fertility might be damaged by coronavirus associated with (i) direct cytopathic effects derived from viral replication and viral dissemination in the testis; and (ii) indirect damage to male fertility derived from immunopathology. In this review, we briefly describe the impaired fertility of humans and animals infected with coronaviruses to deduce the impact of the new coronavirus on male fertility. Together with information related to other coronaviruses, we extrapolate this knowledge to the new coronavirus SARS‐CoV‐2, which may have a significant impact on our understanding of the pathophysiology of this new virus.

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Sperm morphology was once believed as one of the most predictive indicators of pregnancy outcome in assisted reproductive technology (ART). However, the impact of teratozoospermia on in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) outcomes and its offspring remains inconclusive. In order to evaluate the influence of teratozoospermia on pregnancy outcome and newborn status after IVF and ICSI, a retrospective study was conducted. This was a matched case-control study that included 2202 IVF cycles and 2574 ICSI cycles and was conducted at the Reproductive and Genetic Hospital of CITIC-Xiangya in Changsha, China, from June 2013 to June 2018. Patients were divided into two groups based on sperm morphology: teratozoospermia and normal sperm group. The pregnancy outcome and newborn outcome were analyzed. The results indicated that couples with teratozoospermia had a significantly lower optimal embryo rate compared to those with normal sperm morphology in IVF ( P = 0.007), while there were no statistically significant differences between the two groups in terms of the fertilization rate, cleavage rate, implantation rate, and pregnancy rate (all P > 0.05). Additionally, teratozoospermia was associated with lower infant birth weight in multiple births after IVF. With regard to ICSI, there was no significant difference in both pregnancy outcome and newborn outcome between the teratozoospermia and normal groups (both P > 0.05). Furthermore, no increase in the risk of birth defects occurred in the teratozoospermia group after IVF/ICSI. Consequently, we believe that teratozoospermia has limited predictive value for pregnancy outcomes in IVF/ICSI, and has little impact on the resulting offspring if multiple pregnancy is avoided.

Passenger ride comfort has become a focus of attention in rail transportation equipment design, manufacture and later operation to meet people's demand for travel quality. However, comfort is a very subjective concept, which is difficult to quantify and evaluate directly, and can be affected by various factors, leading to the corresponding technologies for ride comfort improvement becoming diverse. In this paper, recent research on the assessment method and improvement measures of railway passenger ride comfort is reviewed. The main types of ride comfort are summarized first according to the sources of discomfort, including static comfort, vibration comfort, noise comfort, aural pressure comfort, thermal comfort and visual comfort. The current assessment methods of ride comfort are introduced from the aspects of environmental parameters and human parameters based on the nature of evaluation indicators. Finally, the improvement technologies for each type of ride comfort are presented.