Integrated motor drives: state of the art and future trends

With increased need for high power density, high efficiency and high temperature capabilities in Aerospace and Automotive applications, Integrated Motor Drives (IMD) offers a potential solution. However, close physical integration of the converter and the machine may also lead to an increase in components temperature. This requires careful mechanical, structural and thermal analysis; and design of the IMD system. This paper reviews existing IMD technologies and their thermal effects on the IMD system. The effects of the power electronics (PE) position on the IMD system and its respective thermal management concepts are also investigated. The challenges faced in designing and manufacturing of an IMD along with the mechanical and structural impacts of close physical integration is also discussed and potential solutions are provided. Potential converter topologies for an IMD like the Matrix converter, 2-level Bridge, 3-level NPC and Multiphase full bridge converters are also reviewed. Wide band gap devices like SiC and GaN and their packaging in power modules for IMDs are also discussed. Power modules components and packaging technologies are also presented

Gendering the careers of young professionals: some early findings from a longitudinal study. in Organizing/theorizing: developments in organization theory and practice

Wonders whether companies actually have employees best interests at heart across physical, mental and spiritual spheres. Posits that most organizations ignore their workforce – not even, in many cases, describing workers as assets! Describes many studies to back up this claim in theis work based on the 2002 Employment Research Unit Annual Conference, in Cardiff, Wales

Withdrawal of maintenance therapy for cytomegalovirus retinitis in AIDS patients exhibiting immunological response to HAART

BACKGROUND: Before the introduction of highly active antiretroviral therapy (HAART), CMV retinitis was a common complication in patients with advanced HIV disease and the therapy was well established; it consisted of an induction phase to control the infection with ganciclovir, followed by a lifelong maintenance phase to avoid or delay relapses. METHODS: To determine the safety of CMV maintenance therapy withdrawal in patients with immune recovery after HAART, 35 patients with treated CMV retinitis, on maintenance therapy, with CD4+ cell count greater than 100 cells/mm³ for at least three months, but almost all patients presented these values for more than six months and viral load < 30000 copies/mL, were prospectively evaluated for the recurrence of CMV disease. Maintenance therapy was withdrawal at inclusion, and patients were monitored for at least 48 weeks by clinical and ophthalmologic evaluations, and by determination of CMV viremia markers (antigenemia-pp65), CD4+/CD8+ counts and plasma HIV RNA levels. Lymphoproliferative assays were performed on 26/35 patients. RESULTS: From 35 patients included, only one had confirmed reactivation of CMV retinitis, at day 120 of follow-up. No patient returned positive antigenemia tests. No correlation between lymphoproliferative assays and CD4+ counts was observed. CONCLUSION: CMV retinitis maintenance therapy discontinuation is safe for those patients with quantitative immune recovery after HAART

Evaluation of lasers to disperse American crows, \u3ci\u3eCorvus brachyrhynchos\u3c/i\u3e, from urban night roosts

American crows (Corvus brachyrhynchos) have a long history of causing agricultural damage in North America. Shooting and bombing at crow night roosts have been employed to reduce such damage. Most roosts were located in rural locations, but in the latter half of the 1900s crows began to roost in urban locations. Urban crow roosts are presently a nationwide problem in the United States. Thousands of crows at a roost create problems for businesses and residents. Improved control techniques are needed. Lasers have been used in Europe to scare and disperse birds but the technique has only recently received formal testing. We treated urban roosts with lasers to determine if crows react to laser light, can be dispersed from roosts, and whether lasers are effective for eliciting roost abandonment. We treated 63 roosts in Woodland, California and recorded the immediate and short-term reactions of crows. We counted crows at five roosts in Davis, California during an 8-day pre-treatment period and then again during a 4-day treatment period to evaluate crow response to laser treatment. Crows reacted to the laser beam. In Woodland 100% of the crows flew immediately away from 49% of the treated roosts. Between 50% to 99% of all crows flew immediately away at 44% of the treated roosts. At 84% of the roosts crows left without vocalizing and at 95% of the roosts flew directly away without circling overhead. Crows returned to all roosts within 15 min. In Davis there was no difference in the number of crows using roosts during the pre-treatment versus treatment periods. Despite initial dispersal upon treatment, crows reoccupied all treated roosts the same night after treatment. No roosts were abandoned. Therefore, we do not recommend lasers as a stand-alone dispersal tool at urban crow roosts