Optical and electrical measurements on UV sensitive photodiodes

The optical and electrical characteristics of the various types of photodiodes potentially useful for UV radiometers were studied. It was concluded that both GaAsP and GaP photodiodes have advantages over silicon photodiodes in terms of spectral response and UV stability. Both GaAsP and GaP have excellent electrical characteristics for low frequency radiometers, although their high capacitance could be inconvenient for high frequency applications. GaAsP is particularly good with respect to dynamic range

Understanding practitioner professionalism in Aboriginal and Torres Strait Islander health: lessons from student and registrar placements at an urban Aboriginal and Torres Strait Islander primary health care service

Aboriginal and Torres Strait Islander peoples continue to be pathologised in medical curriculum, leaving graduates feeling unequipped to effectively work cross-culturally. These factors create barriers to culturally safe health care for Aboriginal and Torres Strait Islander peoples. In this pilot pre-post study, we followed the learning experiences of 7 medical students and 4 medical registrars undertaking clinical placements at an urban Aboriginal and Torres Strait Islander primary health care service in 2014. Through analysis and comparison of pre- and post-placement responses to a paper-based case study of a fictitious Aboriginal patient, we identified four learning principles for medical professionalism: student exposure to nuanced, complex and positive representations of Aboriginal peoples; positive practitioner role modelling; interpersonal skills that build trust and minimise patient-practitioner relational power imbalances; and, knowledge, understanding and skills for providing patient centred, holistic care. Though not exhaustive, these principles can increase the capacity of practitioners to foster culturally safe and optimal health care for Aboriginal peoples. Furthermore, competence and effectiveness in Aboriginal health contexts is an essential component of medical professionalism

Serological response to 13-valent pneumococcal conjugate vaccine in children and adolescents with perinatally acquired HIV infection

BACKGROUND: Children with perinatally acquired HIV (paHIV) remain at an increased risk of pneumococcal infection despite highly active antiretroviral therapy (HAART). Beyond infancy, responses to pneumococcal conjugate vaccine (PCV) remain under-investigated. There are currently no published data on serological response to 13-valent PCV (PCV13) in the HIV-infected populations. METHODS: We measured pneumococcal serotype-specific IgG in 48 paHIV-infected child patients (CP), 27 young adult healthy controls (AHC) and 30 child healthy controls (CHC). Opsonophagocytic assay (OPA) titres for three PCV13-exclusive serotypes were measured in a subset of children. Serotype-specific IgG was repeated 1 and 6 months following PCV13 vaccination of CP and AHC groups. OPA titres for four serotypes were measured at the 1-month time-point. RESULTS: The majority of CP, CHC and AHC had serotype-specific IgG above 0.35 μg/ml at baseline, although OPA activity was undetectable for two of the three serotypes studied. Baseline IgG concentrations were significantly lower in CP than AHC for a proportion of serotypes and were strongly predictive of responses to vaccine. After adjusting for baseline, postvaccination IgG concentrations were comparable, although responses to some serotypes were impaired for CP. OPA correlated well with IgG after vaccination. Detectable HIV viral load was associated with significantly lower IgG concentration and OPA titre. CONCLUSION: Children with paHIV mount a robust serological response to PCV13 for most but not all vaccine serotypes. Viral load suppression with HAART and higher baseline IgG concentration are associated with higher postvaccination antibody levels. This has implications for HAART treatment and vaccination practices

The influence of paediatric HIV infection on circulating B cell subsets and CXCR5+ T helper cells

Antiretroviral therapy (ART) only partially restores HIV-induced alterations in lymphocyte populations. We assessed B and T cell phenotypes in a cohort of children from a single centre in the United Kingdom with perinatally acquired HIV compared to healthy controls. The majority of HIV infected children (44 of 56) were on fully suppressive combination ART. Children with perinatally acquired HIV had significantly lower memory B and CD4(+) CD45RO(+) CXCR5(+) [follicular T helper cell (Tfh)-like] T cell percentages. Detectable viraemia was associated with higher CD21(-) (activated and exhausted/tissue-like memory) B cells. A greater proportion of life spent on suppressive ART was associated with higher memory B cell percentages. These results suggest that early and sustained suppressive ART may preserve B and T cell phenotypes in perinatally acquired HIV and limit deficits in humoral immunity. A lower proportion of circulating Tfh-like cells in HIV infected children appears to be independent of HIV treatment history and ongoing HIV viraemia and warrants further investigation

Fifteen minute consultation: Managing neonatal and childhood herpes encephalitis

Herpes simplex encephalitis (HSE) is the most common single cause of viral encephalitis in infants and children. Treated or untreated, it can be associated with considerable morbidity and mortality, and its presentation is usually insidious and non-specific. Prompt and careful investigation is important in order to establish the diagnosis so that treatment can be optimised. We address some common questions arising when diagnosing and treating presumed HSE throughout childhood

Control of human endometrial stromal cell motility by PDGF-BB, HB-EGF and trophoblast-secreted factors

Human implantation involves extensive tissue remodeling at the fetal-maternal interface. It is becoming increasingly evident that not only trophoblast, but also decidualizing endometrial stromal cells are inherently motile and invasive, and likely contribute to the highly dynamic processes at the implantation site. The present study was undertaken to further characterize the mechanisms involved in the regulation of endometrial stromal cell motility and to identify trophoblast-derived factors that modulate migration. Among local growth factors known to be present at the time of implantation, heparin-binding epidermal growth factor-like growth factor (HB-EGF) triggered chemotaxis (directed locomotion), whereas platelet-derived growth factor (PDGF)-BB elicited both chemotaxis and chemokinesis (non-directed locomotion) of endometrial stromal cells. Supernatants of the trophoblast cell line AC-1M88 and of first trimester villous explant cultures stimulated chemotaxis but not chemokinesis. Proteome profiling for cytokines and angiogenesis factors revealed neither PDGF-BB nor HB-EGF in conditioned media from trophoblast cells or villous explants, while placental growth factor, vascular endothelial growth factor and PDGF-AA were identified as prominent secretory products. Among these, only PDGF-AA triggered endometrial stromal cell chemotaxis. Neutralization of PDGF-AA in trophoblast conditioned media, however, did not diminish chemoattractant activity, suggesting the presence of additional trophoblast-derived chemotactic factors. Pathway inhibitor studies revealed ERK1/2, PI3 kinase/Akt and p38 signaling as relevant for chemotactic motility, whereas chemokinesis depended primarily on PI3 kinase/Akt activation. Both chemotaxis and chemokinesis were stimulated upon inhibition of Rho-associated, coiled-coil containing protein kinase. The chemotactic response to trophoblast secretions was not blunted by inhibition of isolated signaling cascades, indicating activation of overlapping pathways in trophoblast-endometrial communication. In conclusion, trophoblast signals attract endometrial stromal cells, while PDGF-BB and HB-EGF, although not identified as trophoblast-derived, are local growth factors that may serve to fine-tune directed and non-directed migration at the implantation site

Haplotype-based association analysis of general cognitive ability in Generation Scotland, the English Longitudinal Study of Ageing, and UK Biobank

Background: Cognitive ability is a heritable trait with a polygenic architecture, for which several associated variants have been identified using genotype-based and candidate gene approaches. Haplotype-based analyses are a complementary technique that take phased genotype data into account, and potentially provide greater statistical power to detect lower frequency variants. Methods: In the present analysis, three cohort studies (ntotal = 48,002) were utilised: Generation Scotland: Scottish Family Health Study (GS:SFHS), the English Longitudinal Study of Ageing (ELSA), and the UK Biobank. A genome-wide haplotype-based meta-analysis of cognitive ability was performed, as well as a targeted meta-analysis of several gene coding regions. Results: None of the assessed haplotypes provided evidence of a statistically significant association with cognitive ability in either the individual cohorts or the meta-analysis. Within the meta-analysis, the haplotype with the lowest observed P-value overlapped with the D-amino acid oxidase activator (DAOA) gene coding region. This coding region has previously been associated with bipolar disorder, schizophrenia and Alzheimer’s disease, which have all been shown to impact upon cognitive ability. Another potentially interesting region highlighted within the current genome-wide association analysis (GS:SFHS: P = 4.09 x 10-7), was the butyrylcholinesterase (BCHE) gene coding region. The protein encoded by BCHE has been shown to influence the progression of Alzheimer’s disease and its role in cognitive ability merits further investigation. Conclusions: Although no evidence was found for any haplotypes with a statistically significant association with cognitive ability, our results did provide further evidence that the genetic variants contributing to the variance of cognitive ability are likely to be of small effect

Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age

World radiocommunication conference 12 : implications for the spectrum eco-system

Spectrum allocation is once more a key issue facing the global telecommunications industry. Largely overlooked in current debates, however, is the World Radiocommunication Conference (WRC). Decisions taken by WRC shape the future roadmap of the telecommunications industry, not least because it has the ability to shape the global spectrum allocation framework. In the debates of WRC-12 it is possible to identify three main issues: enhancement of the international spectrum regulatory framework, regulatory measures required to introduce Cognitive Radio Systems (CRS) technologies; and, additional spectrum allocation to mobile service. WRC-12 eventually decided not to change the current international radio regulations with regard to the first two issues and agreed to the third issue. The main implications of WRC-12 on the spectrum ecosystem are that most of actors are not in support of the concept of spectrum flexibility associated with trading and that the concept of spectrum open access is not under consideration. This is explained by the observation that spectrum trading and spectrum commons weaken state control over spectrum and challenge the main principles and norms of the international spectrum management regime. In addition, the mobile allocation issue has shown the lack of conformity with the main rules of the regime: regional spectrum allocation in the International Telecommunication Union (ITU) three regions, and the resistance to the slow decision making procedures. In conclusion, while the rules and decision-making procedures of the international spectrum management regime were challenged in the WRC-12, the main principles and norms are still accepted by the majority of countries

Resisting austerity in the era of COVID-19.:Between nationwide mobilisation and decentralised organising in Ecuador

Since 2017, the return of a neoliberal government in Ecuador has been characterized by austerity measures designed to lower state debt, particularly through cuts to social and environmental programs and the privatisation of state institutions. These policies have worsened ongoing economic and environmental crises suffered by the country’s poor, leading to massive protests in October 2019, which temporarily blocked further austerity measures. Yet, in subsequent months, the COVID-19 emergency enabled the government to move forward with neoliberal reforms and with policies promoting the expansion of extractive frontiers and the corporate food system. In this chapter, we examine decentralised organising among anti-neoliberal movements during the pandemic, particularly anti-extractivist and peasant agro-ecological collectives. We confirm prior findings regarding austerity that qualify it as a strategy not only to reduce state expenditure, but also to privately appropriate the commons, actively redirecting wealth to capital. Our research highlights that, in a context where mass protests are hindered by the pandemic, anti-neoliberal resistance in Ecuador operates in flexible articulations or assemblages that respond to shifting contexts. In 2019, marginalized sectors converged on urban political centres, concentrating a popular mass to pressure the central government and later, during COVID-19, local organisations advanced forms of decentralised resistance across the country, constructing or expanding solidarity networks, using legal and digital systems, and mobilizing alliances with local governments. Thus, subaltern anti-neoliberal movements continued to advance a politics of solidarity across changing contexts by flexibly articulating organisationally and tactically