A review of recent work on discharge characteristics during plasma electrolytic oxidation of various metals

The review describes recent progress on understanding and quantification of the various phenomena that take place during plasma electrolytic oxidation, which is in increasing industrial use for production of protective coatings and other surface treatment purposes. A general overview of the process, and some information about usage of these coatings, are provided in the first part of the review. The focus is then on the dielectric breakdown that repeatedly occurs over the surface of the work-piece. These discharges are central to the process, since it is largely via the associated plasmas that oxidation of the substrate takes place and the coating is created. The details are complex, since the discharge characteristics are affected by a number of processing variables. The inter-relationships between electrical conditions, electrolyte composition, coating microstructure and rates of growth, which are linked via the characteristics of the discharges, have become clearer over recent years and these improvements in understanding are summarized here. There is considerable scope for more effective process control, with specific objectives in terms of coating performance and energy efficiency, and an attempt is made to identify key points that are likely to assist this

Hybridization in parasites: consequences for adaptive evolution, pathogenesis and public health in a changing world

[No abstract available

Canine respiratory coronavirus employs caveolin-1-mediated pathway for internalization to HRT-18G cells

Canine respiratory coronavirus (CRCoV), identified in 2003, is a member of the Coronaviridae family. The virus is a betacoronavirus and a close relative of human coronavirus OC43 and bovine coronavirus. Here, we examined entry of CRCoV into human rectal tumor cells (HRT-18G cell line) by analyzing co-localization of single virus particles with cellular markers in the presence or absence of chemical inhibitors of pathways potentially involved in virus entry. We also targeted these pathways using siRNA. The results show that the virus hijacks caveolin-dependent endocytosis to enter cells via endocytic internalization

Wet Granular Materials

Most studies on granular physics have focused on dry granular media, with no liquids between the grains. However, in geology and many real world applications (e.g., food processing, pharmaceuticals, ceramics, civil engineering, constructions, and many industrial applications), liquid is present between the grains. This produces inter-grain cohesion and drastically modifies the mechanical properties of the granular media (e.g., the surface angle can be larger than 90 degrees). Here we present a review of the mechanical properties of wet granular media, with particular emphasis on the effect of cohesion. We also list several open problems that might motivate future studies in this exciting but mostly unexplored field.Comment: review article, accepted for publication in Advances in Physics; tex-style change

Bacteraemia among severely malnourished children infected and uninfected with the human immunodeficiency virus-1 in Kampala, Uganda

BACKGROUND: To establish the magnitude of bacteraemia in severely malnourished children, and describe the types of bacteria and antimicrobial sensitivity by HIV status. METHOD: Isolates were recovered from 76 blood specimens. Antibiotic susceptibility tests were performed using commercial antibiotic disks and demographic and clinical findings were recorded. RESULTS: Of the 450 children 63% were male; median age 17.0 months (inter quartile range, IQR 12–24) and 57% had oedema. 151 (36.7 %) of 411 tested HIV-positive; 76 (17.1%) of 445 blood specimens grew bacterial isolates; 58% were Gram negative – S. typhimurium (27.6%) and S. enteriditis (11.8%). Staph. aureus (26.3%) and Strep. pneumoniae (13.2%) were the main Gram positive organisms. There was no difference in the risk of bacteraemia by HIV status, age < 24 months, male sex, or oedema, except for oral thrush (OR 2.3 CI 1.0–5.1) and hypoalbuminaemia (OR 3.5 CI 1.0–12.1). Isolates from severely immuno-suppressed children (CD4% <15%) were more likely to grow Salmonella enteriditis (OR 5.4; CI 1.6 – 17.4). The isolates were susceptible (≥ 80%) to ciprofloxacin, ceftriaxone and gentamicin; with low susceptibility to chlorampenicol, ampicillin (< 50%) and co-trimoxazole (<25%). Suspicion of bacteraemia had 95.9% sensitivity and 99.2% specificity. Among bacteraemic children, mortality was higher (43.5% vs 20.5%) in the HIV-positive; OR 3.0 (95%CI 1.0, 8.6). CONCLUSION: Bacteraemia affects 1 in every 6 severely malnourished children and carries high mortality especially among the HIV-positive. Given the high level of resistance to common antibiotics, there is need for clinical trials to determine the best combinations of antibiotics for management of bacteraemia in severely malnourished children

Adherence to yoga and exercise interventions in a 6-month clinical trial

<p>Abstract</p> <p>Background</p> <p>To determine factors that predict adherence to a mind-body intervention in a randomized trial.</p> <p>Design</p> <p>We analyzed adherence data from a 3-arm trial involving 135 generally healthy seniors 65–85 years of age randomized to a 6-month intervention consisting of: an Iyengar yoga class with home practice, an exercise class with home practice, or a wait-list control group. Outcome measures included cognitive function, mood, fatigue, anxiety, health-related quality of life, and physical measures. Adherence to the intervention was obtained by class attendance and biweekly home practice logs.</p> <p>Results</p> <p>The drop-out rate was 13%. Among the completers of the two active interventions, average yoga class attendance was 77% and home practice occurred 64% of all days. Average exercise class attendance was 69% and home exercise occurred 54% of all days. There were no clear effects of adherence on the significant study outcomes (quality of life and physical measures). Class attendance was significantly correlated with baseline measures of depression, fatigue, and physical components of health-related quality of life. Significant differences in baseline measures were also found between study completers and drop-outs in the active interventions. Adherence was not related to age, gender, or education level.</p> <p>Conclusion</p> <p>Healthy seniors have good attendance at classes with a physically active intervention. Home practice takes place over half of the time. Decreased adherence to a potentially beneficial intervention has the potential to decrease the effect of the intervention in a clinical trial because subjects who might sustain the greatest benefit will receive a lower dose of the intervention and subjects with higher adherence rates may be functioning closer to maximum ability before the intervention. Strategies to maximize adherence among subjects at greater risk for low adherence will be important for future trials, especially complementary treatments requiring greater effort than simple pill-taking.</p

Human Immunity and the Design of Multi-Component, Single Target Vaccines

BACKGROUND: Inclusion of multiple immunogens to target a single organism is a strategy being pursued for many experimental vaccines, especially where it is difficult to generate a strongly protective response from a single immunogen. Although there are many human vaccines that contain multiple defined immunogens, in almost every case each component targets a different pathogen. As a consequence, there is little practical experience for deciding where the increased complexity of vaccines with multiple defined immunogens vaccines targeting single pathogens will be justifiable. METHODOLOGY/PRINCIPAL FINDINGS: A mathematical model, with immunogenicity parameters derived from a database of human responses to established vaccines, was used to predict the increase in the efficacy and the proportion of the population protected resulting from addition of further immunogens. The gains depended on the relative protection and the range of responses in the population to each immunogen and also to the correlation of the responses between immunogens. In most scenarios modeled, the gain in overall efficacy obtained by adding more immunogens was comparable to gains obtained from a single immunogen through the use of better formulations or adjuvants. Multi-component single target vaccines were more effective at decreasing the proportion of poor responders than increasing the overall efficacy of the vaccine in a population. CONCLUSIONS/SIGNIFICANCE: Inclusion of limited number of antigens in a vaccine aimed at targeting a single organism will increase efficacy, but the gains are relatively modest and for a practical vaccine there are constraints that are likely to limit multi-component single target vaccines to a small number of key antigens. The model predicts that this type of vaccine will be most useful where the critical issue is the reduction in proportion of poor responders

Quantifying trends in disease impact to produce a consistent and reproducible definition of an emerging infectious disease.

The proper allocation of public health resources for research and control requires quantification of both a disease's current burden and the trend in its impact. Infectious diseases that have been labeled as "emerging infectious diseases" (EIDs) have received heightened scientific and public attention and resources. However, the label 'emerging' is rarely backed by quantitative analysis and is often used subjectively. This can lead to over-allocation of resources to diseases that are incorrectly labelled "emerging," and insufficient allocation of resources to diseases for which evidence of an increasing or high sustained impact is strong. We suggest a simple quantitative approach, segmented regression, to characterize the trends and emergence of diseases. Segmented regression identifies one or more trends in a time series and determines the most statistically parsimonious split(s) (or joinpoints) in the time series. These joinpoints in the time series indicate time points when a change in trend occurred and may identify periods in which drivers of disease impact change. We illustrate the method by analyzing temporal patterns in incidence data for twelve diseases. This approach provides a way to classify a disease as currently emerging, re-emerging, receding, or stable based on temporal trends, as well as to pinpoint the time when the change in these trends happened. We argue that quantitative approaches to defining emergence based on the trend in impact of a disease can, with appropriate context, be used to prioritize resources for research and control. Implementing this more rigorous definition of an EID will require buy-in and enforcement from scientists, policy makers, peer reviewers and journal editors, but has the potential to improve resource allocation for global health

Human-like PB2 627K Influenza Virus Polymerase Activity Is Regulated by Importin-α1 and -α7

Influenza A viruses may cross species barriers and transmit to humans with the potential to cause pandemics. Interplay of human- (PB2 627K) and avian-like (PB2 627E) influenza polymerase complexes with unknown host factors have been postulated to play a key role in interspecies transmission. Here, we have identified human importin-α isoforms (α1 and α7) as positive regulators of human- but not avian-like polymerase activity. Human-like polymerase activity correlated with efficient recruitment of α1 and α7 to viral ribonucleoprotein complexes (vRNPs) without affecting subcellular localization. We also observed that human-like influenza virus growth was impaired in α1 and α7 downregulated human lung cells. Mice lacking α7 were less susceptible to human- but not avian-like influenza virus infection. Thus, α1 and α7 are positive regulators of human-like polymerase activity and pathogenicity beyond their role in nuclear transport