Tensile Behavior of Low Density Thermally Bonded Nonwoven Material

A discontinuous and non-uniform microstructure of alow-density thermally bonded nonwoven materialdisplays in a complicated and unstable tensilebehavior. This paper reports uniaxial tensile tests of alow density thermally bonded nonwoven toinvestigate the effect of the specimen size and shapefactor, as well as the cyclic tensile loading conditionsemployed to investigate the deformational behaviorand performance of the nonwoven at differentloading stages. The experimental data are comparedwith results of microscopic image analysis and FEmodels

A micromechanism study of thermosonic gold wire bonding on aluminum pad

A micromechanism of thermosonic gold wire bonding was elaborated by examining its interfacial characteristics as a result of the bonding process, including the fragmentation of the native aluminum oxide layer on Al pads, and formation of initial intermetallic compounds IMCs. It is found that the existence of an approximately 5 nm thick native oxide layer on original Al pads has a significant effect on the bonding, and the nucleation of IMCs during the bonding process must overcome this relatively inert thin film. Bonding strength was fundamentally determined by the degree of fragmentation of the oxide films, through which the formation of IMCs can be initiated due to the direct contact of the metal surfaces to be bonded. The extent of fracture the oxide layer was strongly influenced by the level of ultrasonic power, as at its high level alumina fragmentation becomes pervasive resulting in contiguous alloy interfaces and robust bonds. The IMCs formed at the interfaces were identified as Al₄Al and AuAl₂ with a thickness of 150–300 nm. The formation mechanism of such IMCs was explained by the effective heat of formation theory.This research was funded as a PMI2 Project Grant No. RC 41 through the UK Department for Innovation, Universities and Skills DIUS

A micromechanism study of thermosonic gold wire bonding on aluminum pad

A micromechanism of thermosonic gold wire bonding was elaborated by examining its interfacial characteristics as a result of the bonding process, including the fragmentation of the native aluminum oxide layer on Al pads, and formation of initial intermetallic compounds IMCs. It is found that the existence of an approximately 5 nm thick native oxide layer on original Al pads has a significant effect on the bonding, and the nucleation of IMCs during the bonding process must overcome this relatively inert thin film. Bonding strength was fundamentally determined by the degree of fragmentation of the oxide films, through which the formation of IMCs can be initiated due to the direct contact of the metal surfaces to be bonded. The extent of fracture the oxide layer was strongly influenced by the level of ultrasonic power, as at its high level alumina fragmentation becomes pervasive resulting in contiguous alloy interfaces and robust bonds. The IMCs formed at the interfaces were identified as Al₄Al and AuAl₂ with a thickness of 150–300 nm. The formation mechanism of such IMCs was explained by the effective heat of formation theory.This research was funded as a PMI2 Project Grant No. RC 41 through the UK Department for Innovation, Universities and Skills DIUS

Women's motivation for family planning in Kisii District: potentials and barriers

This paper is tentatively arguing that women in Kisii District are confronted with a number of factors which are acting both as potentials as well as barriers to their motivation for family planning. Focus is put on progressive and regressive changes in female status and role at the household level. Factors such as changing sexual division of labour, changing gender relations and gender roles and changing decision-making pattern are discussed as well as the way in which these changes are interacting positively or negatively on women’s motivation for limiting their child births and making use of family planning. As men and their attitude to family planning seem to create a major barrier for many women, research on men was included in the study, and their attitudes are tentatively discussed. Other factors interacting with women's motivation for family planning are considered to be value and costs of children and fears of side-effects. Also availability and quality of family planning services are discussed. It is argued that a number of potential users are lost because of inadequate services

Men in the Remaking: Conversion Narratives and Born-Again Masculinity in Zambia

The born-again discourse is a central characteristic of Pentecostal Christianity in Africa. In the study of African Christianities, this discourse and the way it (re)shapes people’s moral, religious, and social identities has received much attention. However, hardly any attention has been paid to its effects on men as gendered beings. In the study of men and masculinities in Africa, on the other hand, neither religion in general nor born-again Christianity in particular are taken into account as relevant factors in the construction of masculinities. On the basis of a detailed analysis of interviews with men who are members of a Pentecostal church in Lusaka, Zambia, this article investigates how men’s gender identities are reshaped by becoming and being born-again and how born-again conversion produces new forms of masculinity. The observed Pentecostal transformation of masculinity is interpreted in relation to men’s social vulnerability, particularly in the context of the HIV epidemic in Zambia

Monitoring and evaluation in global HIV/AIDS control - weighing incentives and disincentives for coordination among global and local actors

This paper discusses coordination efforts of both donors and recipient countries in the monitoring and evaluation (M&E) of health outcomes in the field of HIV/AIDS. The coordination of M&E is a much underdeveloped area in HIV/AIDS programming in which, however, important first steps towards better synchronisation have already been taken. In this paper, we review the concepts and meanings commonly applied to M&E, and approaches and strategies for better coordination of M&E in the field of HIV/AIDS. Most importantly, drawing on this analysis, we examine why the present structure of global health governance in this area is not creating strong enough incentives for effective coordination among global and local actors. Copyright © 2010 John Wiley & Sons, Ltd

Damage and fracture of biological and biomedical materials

In the last decade, the topic of damage and fracture of biological and biomedical materials not only became one of the central research areas in the healthcare engineering, but also drew attention of specialists in mechanics of materials and fracture. One of the motivations behind these developments is a continuing increase in the use of medical devices made of various materials that are exposed to challenging loading and environmental conditions. Many of them should have significant levels of durability to avoid recurring surgical interventions (typical examples being implants for hip and knee replacements or dental implants). A lack of understanding of their responses to specific conditions and interaction with biological environment can result in malfunctioning and failures or traumas to surrounding tissues. The typical application problems are additionally complicated by insufficient knowledge of mechanical behaviour of biomaterials at various length and time scales and under different loading conditions including their fracture and fatigue. These types of application presuppose the understanding of properties and performance of two classes of materials – natural (biomaterials) and engineering (biomedical materials), as well as their interaction at interfaces between, on the one hand, life tissues (or organs) and, on the other hand, implants and prostheses. Among engineering materials, used in such applications, are familiar metals and alloys, ceramics, polymers and composites. Their properties and performance seem to be well studied; still, biomedical applications are characterised by rather specific usability envelopes as well as, in most cases, additional constraints such as non-toxicity (biocompatibility) and/or resistance to harsh physiological environments. In some cases, a requirement, opposite to structural integrity, is needed, e.g. controlled degradation for scaffolds and stents..

Talking South African fathers: a critical examination of men’s constructions and experiences of fatherhood and fatherlessness

The absence of biological fathers in South Africa has been constructed as a problem for children of both sexes but more so for boy-children. Arguably the dominant discourse in this respect has demonized non-nuclear, female-headed households. Fathers are constructed as either absent or ‘bad’. Thus it has become important to explore more closely how male care-givers have been experienced by groups of men in South Africa. This article examines discourses of fatherhood and fatherlessness by drawing on qualitative interviews with a group of 29 men who speak about their reported experiences and understandings of being fathered or growing up without biological fathers. Two major and intertwined subjugated discourses about adult men’s experiences of being fathered that counter- balance the prevailing discourses about meaning of fatherhood and fatherlessness became evident, namely, ‘being always there’ and ‘talking fatherhood’. The importance of the experience of fatherhood as ‘being there’, which relates to a quality of time and relationship between child and father rather than physical time together, is illustrated. It is not only biological fathers who can ‘be there’ for their sons but also social fathers, other significant male role models and father figures who step in at different times in participants’ lives when biological fathers are unavailable for whatever reason. Second, many positive experiences of fathers or father figures that resist a traditional role of authority and control and subscribe to more nurturant and non-violent forms of care, represented as ‘talking’ fathers, are underlined. If we are to better understand the impact of colonial and apartheid history and its legacy on family life in contemporary society, there is a need for more historically and contextually informed studies on the meaning of fatherhood and fatherlessness.Web of Scienc