In this article, we examine knowledge of contraceptives and sexually transmitted diseases (STDs) and contraceptive practices amongst young Vietnamese people. We conducted a qualitative study on sexuality and abortion with young people in Ho Chi Minh City, Vietnam. Twelve female and 4 male young people were individually interviewed using an in-depth interview technique. We found that condoms and pills were contraceptives known by almost all young people, but their knowledge of condoms and pills was still inadequate. Fears of side effects of taking pills and rumors and beliefs regarding condoms were quite common among young people. The limitations in young people's knowledge of contraceptives and STDs were a reflection of limited sources of their knowledge. Sexual education provided by educational institutions and within families was very basic. It did not provide clear knowledge on the sensitive topics such as contraceptive methods, and other issues related to sexuality for unmarried people. From a gender perspective, there are two points to note here: While sex issues were discussed openly among unmarried men, most unmarried women felt uncomfortable or expressed difficulty when talking about these issues; and the passiveness of unmarried women in making the decision of using condoms as well as contraceptives was marked. Amongst young people, the use of contraceptives was based mainly on ineffective methods including withdrawal and periodic abstinence. Further, young people's understanding of these methods was neither clear nor adequate. For the young people who did not use any contraceptives, sexual relations occurred unexpectedly. We conclude that creating a climate in which sexual issues can be discussed openly is an important step for the improvement of sexual health for young people. This will inevitably improve knowledge and understanding of contraceptives and STDs and may lead to a safer sexual life among this group of young people.

This paper discusses the impacts of gender norms on the sexual life and experience of a group of young Vietnamese people. It is based on a qualitative study on sexuality and abortion among young people in Ho Chi Minh City, Vietnam. There were two general attitudes towards premarital sex. One view supported young people in a serious, loving relationship engaging in sex before marriage; the other opposed premarital sex because it affected the reputation of girls and their families. These general attitudes were similar to the views on virginity: one group believed strongly in girls maintaining their virginity and the other group emphasised love, emotion and trust, not virginity, as the most important criteria for marriage. Among women there were more supporters than opponents of the traditional view of premarital sex and virginity. Premarital sex was more acceptable for young people in a serious, loving relationship with certain commitment to marriage. Young men considered sex a way to express their love and to become more intimate. Women's view was that premarital sex only occurred within a serious, loving relationship or when there was a serious commitment to marriage. It is clear that young people's sexual life is shaped and constrained by gender norms through political interventions, sexual education and moral judgements. Under the pressure of these norms, young people face many difficulties in order to fulfill a safe and satisfying sexual life.

High bearing load roller shafts are made of high performance steels as they are subjected to severe fatigue conditions, which combine a shrink-fit load and a rotating bending. Alternating stress intensity for fatigue analysis under said conditions, using elastic and maximum shear stress theories, shows a waving behaviour within a short distance near the contact edge. This discovery is observed by using structured 3D finite element models with surface-to-surface contact and element sizes varying from a coarse size far from the contact edge down to the order of sliding displacement near the contact edge. These FE models provide proof that stresses near the contact edge increase indefinitely when element size reduces. It is also found that the maximum alternating stress intensity at the depth of one ten-thousandth of the shaft diameter, using the friction coefficient of 0.01 in FE models, gives a good comparison with empirical fatigue data of classic shrink-fit assemblies for a wide range of geometry and loading.