Experimental and CFD airflow studies of a cleanroom with special respect to air supply inlets

Investigations were carried out into the airflow in a non-unidirectional airflow cleanroom and its affect on the local airborne particle cleanliness The main influence was the method of air supply A supply inlet with no diffuser gave a pronounced downward jet flow and low levels of contamination below it, but poorer than average conditions in much of the rest of the room A 4-way diffuser gave much better air mixing and a more even airborne particle concentration throughout the cleanroom Other variables such as air inlet supply velocity, temperature difference between air supply and the room, and the release position of contamination also influenced the local airborne cleanliness A CFD analysis of airflow fields in a cleanroom was compared with measured values It was considered that a turbulent intensity of 6%, and a hydraulic diameter based on the actual size of the air inlet, should be used for the inlet boundary conditions and, when combined with a k-epsilon standard turbulence model, a reasonable prediction of the airflow and airborne particle concentration was obtained

'Bring us the female condom': HIV intervention, gender and political empowerment in two South African communities

The quotation which heads this paper encapsulates two important issues in AIDS research in South Africa: the one is substantive, the other methodological. The link between them is the rapid spread of HIV/AIDS in the country and the indication not only that women are more at risk of infection than men, but that, as in many other parts of the world, much of their vulnerability is gender based. ‘Bring us the female condom’ sums up the response of one particular group of black South African women to AIDS education. Their demand was a reflection of their relative domestic and gender empowerment - and also a high degree of political mobilization. However, their position is not necessarily shared by other black women. But the call for the female condom went further: it was a challenge to rethink our position as researchers and particularly to face the implications of commitment to a participatory model of community based intervention research

A comprehensive survey of hearing questionnaires: how many are there, what do they measure, and how have they been validated?

The self-report questionnaire is a popular tool for measuring outcomes in trials of interventions for hearing impairment. Many have been designed over the last fifty years, and there is no single standard questionnaire that is widely accepted and used. We felt it would be a valuable resource to have a comprehensive collection of all adult hearing-loss questionnaires (excluding those wholly devoted to tinnitus, children, or cochlear implants) and to survey their degree of validation. We collated copies of every published hearing difficulty questionnaire that we could find. The search was primarily done by iterative reference searching. Questionnaire topics were obtained by mapping the text of each questionnaire onto a set of categories; reports of validation methods were taken from the primary paper(s) on each questionnaire. In total we found 139 hearing-specific questionnaires (though many others were found that were primarily about something else). Though not formally systematic, we believe that we have included every questionnaire that is important, most of those of some notice, and a fair fraction of those obscure. We classified 111 as “primary” and the remaining 28 as “contractions”, being shortened versions of a primary without any new questions. In total, there were 3618 items across all the primary questionnaires. The median number of items per questionnaire was 20; the maximum was 158. Across all items, about one third were concerned with the person’s own hearing, another third with the repercussions of it, and about a quarter with hearing aids. There was a wide range in validation methods, from only using items chosen statistically from wider pools and with formal validation against independent measures of clinical outcomes, to just reporting a correlation with an audiogram measure of hearing loss. The “state of play” of the field of hearing questionnaires will be discussed

Emotion processing and social participation following stroke : study protocol

Peer reviewedPublisher PD

The identification of markers of macrophage differentiation in PMA-stimulated THP-1 Cells and monocyte-derived macrophages

Differentiated macrophages are the resident tissue phagocytes and sentinel cells of the innate immune response. The phenotype of mature tissue macrophages represents the composite of environmental and differentiation-dependent imprinting. Phorbol-12-myristate-13-acetate (PMA) and 1,25-dihydroxyvitamin D3 (VD3) are stimuli commonly used to induce macrophage differentiation in monocytic cell lines but the extent of differentiation in comparison to primary tissue macrophages is unclear. We have compared the phenotype of the promonocytic THP-1 cell line after various protocols of differentiation utilising VD3 and PMA in comparison to primary human monocytes or monocyte-derived macrophages (MDM). Both stimuli induced changes in cell morphology indicative of differentiation but neither showed differentiation comparable to MDM. In contrast, PMA treatment followed by 5 days resting in culture without PMA (PMAr) increased cytoplasmic to nuclear ratio, increased mitochondrial and lysosomal numbers and altered differentiation-dependent cell surface markers in a pattern similar to MDM. Moreover, PMAr cells showed relative resistance to apoptotic stimuli and maintained levels of the differentiation-dependent anti-apoptotic protein Mcl-1 similar to MDM. PMAr cells retained a high phagocytic capacity for latex beads, and expressed a cytokine profile that resembled MDM in response to TLR ligands, in particular with marked TLR2 responses. Moreover, both MDM and PMAr retained marked plasticity to stimulus-directed polarization. These findings suggest a modified PMA differentiation protocol can enhance macrophage differentiation of THP-1 cells and identify increased numbers of mitochondria and lysosomes, resistance to apoptosis and the potency of TLR2 responses as important discriminators of the level of macrophage differentiation for transformed cells

The subjective effect of multiple co-channel frequency modulated television interference

As the geostationary orbit/spectrum becomes saturated, there is a need for the ability to reuse frequency assignments. Protection ratios (the ratio of wanted signal power to interfering signal power at the receiver) play a key role in determining efficient frequency reuse plans. A knowledge of the manner in which multiple sources of co-channel interference combine is vital in determining protection ratio requirements such that suitable margin may be allocated for multiple interfering signals. Results of tests examining the subjective assessment of multiple co-channel frequency modulated television signals interfering with another frequency modulated TV system are presented

Optically controlled grippers for manipulating micron-sized particles

We report the development of a joystick controlled gripper for the real-time manipulation of micron-sized objects, driven using holographic optical tweezers (HOTs). The gripper consists of an arrangement of four silica beads, located in optical traps, which can be positioned and scaled in order to trap an object indirectly. The joystick can be used to grasp, move (lateral or axial), and change the orientation of the target object. The ability to trap objects indirectly allows us to demonstrate the manipulation of a strongly scattering micron-sized metallic particle

Cognitive effects following acute wild blueberry supplementation in 7 – 10 year old children

Purpose: Previously, anthocyanin-rich blueberry treatments have shown positive effects on cognition in both animals and human adults. However, little research has considered whether these benefits transfer to children. Here we describe an acute time-course and dose–response investigation considering whether these cognitive benefits extend to children. Methods: Using a double-blind cross-over design, on three occasions children (n = 21; 7–10 years) consumed placebo (vehicle) or blueberry drinks containing 15 or 30 g freeze-dried wild blueberry (WBB) powder. A cognitive battery including tests of verbal memory, word recognition, response interference, response inhibition and levels of processing was performed at baseline, and 1.15, 3 and 6 h following treatment. Results: Significant WBB-related improvements included final immediate recall at 1.15 h, delayed word recognition sustained over each period, and accuracy on cognitively demanding incongruent trials in the interference task at 3h. Importantly, across all measures, cognitive performance improved, consistent with a dose–response model, with the best performance following 30 g WBB and the worst following vehicle. Conclusion: Findings demonstrate WBB-related cognitive improvements in 7- to 10-year-old children. These effects would seem to be particularly sensitive to the cognitive demand of task