Effects of radiation on the leach rates of vitrified radioactive waste

This report reviews the possible effects of both radiation damage to the glass and of radiolysis of the leachant on the leaching behaviour of vitrified radioactive waste. It has been stimulated particularly by recent papers, which have suggested that the leach rates of glasses will be enhanced by large factors after a ‘critical’ dose of radiation from alpha decays. These experiments have been conducted at highly accelerated rates using ion beams. The relationship between these experiments and the situation in vitrified waste has been assessed, taking into account the fact that experiments using alpha emitters incorporated in the glass have failed to find significantly enhanced leach rates after doses about five times larger than those equivalent to this ‘critical’ dose. It is concluded that these differences are observed partly because the ion beam experiments are carried out at such high dose rates that some recovery effects important at lower rates do not come into play. In the case of experiments with 2 keV argon ions, surface effects other than genuine radiation damage must be taken into account. In practice, if water has penetrated the canister, vitrified waste will be irradiated in the presence of the leaching solution. Enhancements of the leach rate due to the transient effects of radiation in the solid are shown to be completely negligible. The effects of radiolysis of the leaching solution and of any air in contact with the solution have also been considered in some detail and related to recent experiments by McVay and Pederson. It is shown that these radiolysis effects will not lead to any situations requiring special precautions in practice, although changes in surface leach rate by small factors can be expected under some circumstances. Any effect of irradiation on leach rates must be seen in the context of a waste repository. Along with other studies we hold the view that the rate of loss of material will be limited by the access of water to the repository, and will therefore depend on the effective saturation solubility of the glass in the leachant, not on the leach rate as usually determined in laboratory tests. Radiation damage is not expected to change the saturation solubility by more than a factor of two or three

Women who experience feelings of aversion while breastfeeding: A meta-ethnographic review.

PROBLEM:Limited literature is available about women who wish to breastfeed but experience unexpected feelings of aversion in reaction to their infant suckling at the breast while breastfeeding. BACKGROUND:Breastfeeding benefits mothers, infants and society yet breastfeeding rates continue to fall below recommendations in part due to inadequate tailored support after hospital discharge. Influences on breastfeeding are complex and include many physiological, psychosocial and cultural factors. AIM:To better understand the experience of women who have feelings of aversion during breastfeeding by synthesising the existing literature. METHODS:MEDLINE, CINAHL, PsycINFO, Maternity and Infant Care databases were searched for relevant literature published between 2000 to 2019. Using Covidence software, five qualitative research studies were identified. Studies were then analysed using meta-ethnographic qualitative synthesis. FINDINGS:Feelings of aversion during breastfeeding were described as visceral and overwhelming; leading to feelings of shame and inadequacy. This synthesis identified five findings; a central conceptual category of "it's such a strong feeling of get away from me" with four key metaphors translated from this central conceptual category: "I do it because I feel it is best for my baby", "I can't control those feelings", "I should be able to breastfeed my son and enjoy it", and "I'm glad I did it". This phenomenon may negatively affect a women's sense of self and impact on the mother-infant relationship. CONCLUSION:Some women who want to breastfeed can experience feelings of aversion while breastfeeding. The feelings of 'aversion' while breastfeeding can inhibit women from achieving their personal breastfeeding goals

Acute and Chronic Effects of Exercise on Appetite, Energy Intake, and Appetite-Related Hormones: The Modulating Effect of Adiposity, Sex, and Habitual Physical Activity.

Exercise facilitates weight control, partly through effects on appetite regulation. Single bouts of exercise induce a short-term energy deficit without stimulating compensatory effects on appetite, whilst limited evidence suggests that exercise training may modify subjective and homeostatic mediators of appetite in directions associated with enhanced meal-induced satiety. However, a large variability in responses exists between individuals. This article reviews the evidence relating to how adiposity, sex, and habitual physical activity modulate exercise-induced appetite, energy intake, and appetite-related hormone responses. The balance of evidence suggests that adiposity and sex do not modify appetite or energy intake responses to acute or chronic exercise interventions, but individuals with higher habitual physical activity levels may better adjust energy intake in response to energy balance perturbations. The effect of these individual characteristics and behaviours on appetite-related hormone responses to exercise remains equivocal. These findings support the continued promotion of exercise as a strategy for inducing short-term energy deficits irrespective of adiposity and sex, as well as the ability of exercise to positively influence energy balance over the longer term. Future well-controlled studies are required to further ascertain the potential mediators of appetite responses to exercise

Morphological and Structural Aspects of the Extremely Halophilic Archaeon Haloquadratum walsbyi

Ultrathin square cell Haloquadratum walsbyi from the Archaea domain are the most abundant microorganisms in the hypersaline water of coastal salterns and continental salt lakes. In this work, we explore the cell surface of these microorganisms using amplitude-modulation atomic-force microscopy in nearly physiological conditions. We demonstrate the presence of a regular corrugation with a periodicity of 16–20 nm attributed to the surface layer (S-layer) protein lattice, striped domains asymmetrically distributed on the cell faces and peculiar bulges correlated with the presence of intracellular granules. Besides, subsequent images of cell evolution during the drying process indicate the presence of an external capsule that might correspond to the giant protein halomucin, predicted by the genome but never before observed by other microscopy studies

Mortality and causes of death in people diagnosed with HIV in the era of highly active antiretroviral therapy compared with the general population: an analysis of a national observational cohort

BACKGROUND: Deaths in HIV-positive people have decreased since the introduction of highly active antiretroviral therapy (HAART) in 1996. Fewer AIDS-related deaths and an ageing cohort have resulted in an increase in the proportion of HIV patients dying from non-AIDS-related disorders. Here we describe mortality and causes of death in people diagnosed with HIV in the HAART era compared with the general population. METHODS: In this observational analysis, we linked cohort data collected by Public Health England (PHE) for individuals aged 15 years and older, diagnosed with HIV in England and Wales from 1997 to 2012, to the Office for National Statistics (ONS) national mortality register. Cohort inclusion began at diagnosis with follow-up clinical information collected every year from all 220 National Health Service (NHS) HIV outpatient clinics nationwide. To classify causes of death we used a modified Coding Causes of Death in HIV (CoDe) protocol, which uses death certificate data and clinical markers. We applied Kaplan-Meier analysis for survival curves and mortality rate estimation and Cox regression to establish independent predictors of all-cause mortality, adjusting for sex, infection route, age at diagnosis, region of birth, year of diagnosis, late diagnosis, and history of HAART. We used standardised mortality ratios (SMRs) to make comparisons with the general population. FINDINGS: Between 1997 and 2012, 88 994 people were diagnosed with HIV, contributing 448 839 person-years of follow up. By the end of 2012, 5302 (6%) patients had died (all-cause mortality 118 per 10 000 person-years, 95% CI 115–121). In multivariable analysis, late diagnosis was a strong predictor of death (hazard ratio [HR] 3·50, 95% CI 3·13–3·92). People diagnosed more recently had a lower risk of death (2003–07: HR 0·66, 95% CI 0·62–0·70; 2008–12: HR 0·65, 95% CI 0·60–0·71). Cause of death was determinable for 4808 (91%) of 5302 patients; most deaths (2791 [58%] of 4808) were attributable to AIDS-defining illnesses. Cohort mortality was significantly higher than the general population for all causes (SMR 5·7, 95% CI 5·5–5·8), particularly non-AIDS infections (10·8, 9·8–12·0) and liver disease (3·7, 3·3–4·2). All-cause mortality was highest in the year after diagnosis (SMR 24·3, 95% CI 23·4–25·2). INTERPRETATION: Despite the availability of free treatment and care in the UK, AIDS continues to account for the majority of deaths in HIV-positive people, and mortality remains higher in HIV-positive people than in the general population. These findings highlight the importance of prompt diagnosis, care engagement, and optimum management of comorbidities in reducing mortality in people with HIV

Provision of foot health services for people with rheumatoid arthritis in New South Wales: a web-based survey of local podiatrists

Background: It is unclear if podiatric foot care for people with rheumatoid arthritis (RA) in New South Wales (NSW) meets current clinical recommendations. The objective of this study was to survey podiatrists' perceptions of the nature of podiatric foot care provision for people who have RA in NSW.Methods: An anonymous, cross-sectional survey with a web-based questionnaire was conducted. The survey questionnaire was developed according to clinical experience and current foot care recommendations. State registered podiatrists practising in the state of NSW were invited to participate. The survey link was distributed initially via email to members of the Australian Podiatry Association (NSW), and distributed further through snowballing techniques using professional networks. Data was analysed to assess significant associations between adherence to clinical practice guidelines, and private/public podiatry practices.Results: 86 podiatrists participated in the survey (78% from private practice, 22% from public practice). Respondents largely did not adhere to formal guidelines to manage their patients (88%). Only one respondent offered a dedicated service for patients with RA. Respondents indicated that the primary mode of accessing podiatry was by self-referral (68%). Significant variation was observed regarding access to disease and foot specific assessments and treatment strategies. Assessment methods such as administration of patient reported outcome measures, vascular and neurological assessments were not conducted by all respondents. Similarly, routine foot care strategies such as prescription of foot orthoses, foot health advice and footwear were not employed by all respondents.Conclusions: The results identified issues in foot care provision which should be explored through further research. Foot care provision in NSW does not appear to meet the current recommended standards for the management of foot problems in people who have RA. Improvements to foot care could be undertaken in terms of providing better access to examination techniques and treatment strategies that are recommended by evidence based treatment paradigms. © 2013 Hendry et al.; licensee BioMed Central Ltd

Defining linkage to care following human immunodeficiency virus (HIV) diagnosis for public health monitoring in Europe

Prompt linkage to human immunodeficiency virus (HIV) care after diagnosis is crucial to ensure optimal patient outcomes. However, few countries monitor this important public health marker and different definitions have been applied, making country and study comparisons difficult. This article presents an expert-agreed, standard definition of linkage to care for a pragmatic approach to public health monitoring, appropriate to the European context. Here, linkage to care is defined as patient entry into specialist HIV care after diagnosis, measured as the time between the HIV diagnosis date and one of the following markers: either the first clinic attendance date, first CD4+ cell count or viral load date, or HIV treatment start date, depending on data availability; Linkage is considered prompt if within 3 months of diagnosis. Application of this definition by researchers and public health professionals when reporting surveillance or research data relating to linkage to care after HIV diagnosis will enable reliable comparisons across countries, better assessment of the success of health services programmes aimed at improving peoples access to HIV treatment and care and the identification of barriers limiting access to HIV care across Europe

The NeuARt II system: a viewing tool for neuroanatomical data based on published neuroanatomical atlases

BACKGROUND: Anatomical studies of neural circuitry describing the basic wiring diagram of the brain produce intrinsically spatial, highly complex data of great value to the neuroscience community. Published neuroanatomical atlases provide a spatial framework for these studies. We have built an informatics framework based on these atlases for the representation of neuroanatomical knowledge. This framework not only captures current methods of anatomical data acquisition and analysis, it allows these studies to be collated, compared and synthesized within a single system. RESULTS: We have developed an atlas-viewing application ('NeuARt II') in the Java language with unique functional properties. These include the ability to use copyrighted atlases as templates within which users may view, save and retrieve data-maps and annotate them with volumetric delineations. NeuARt II also permits users to view multiple levels on multiple atlases at once. Each data-map in this system is simply a stack of vector images with one image per atlas level, so any set of accurate drawings made onto a supported atlas (in vector graphics format) could be uploaded into NeuARt II. Presently the database is populated with a corpus of high-quality neuroanatomical data from the laboratory of Dr Larry Swanson (consisting 64 highly-detailed maps of PHAL tract-tracing experiments, made up of 1039 separate drawings that were published in 27 primary research publications over 17 years). Herein we take selective examples from these data to demonstrate the features of NeuArt II. Our informatics tool permits users to browse, query and compare these maps. The NeuARt II tool operates within a bioinformatics knowledge management platform (called 'NeuroScholar') either as a standalone or a plug-in application. CONCLUSION: Anatomical localization is fundamental to neuroscientific work and atlases provide an easily-understood framework that is widely used by neuroanatomists and non-neuroanatomists alike. NeuARt II, the neuroinformatics tool presented here, provides an accurate and powerful way of representing neuroanatomical data in the context of commonly-used brain atlases for visualization, comparison and analysis. Furthermore, it provides a framework that supports the delivery and manipulation of mapped data either as a standalone system or as a component in a larger knowledge management system

Changing indications and socio-demographic determinants of (adeno)tonsillectomy among children in England--are they linked? A retrospective analysis of hospital data.

OBJECTIVE: To assess whether increased awareness and diagnosis of obstructive sleep apnoea syndrome (OSAS) and national guidance on tonsillectomy for recurrent tonsillitis have influenced the socio-demographic profile of children who underwent tonsillectomy over the last decade. METHOD: Retrospective time-trends study of Hospital Episodes Statistics data. We examined the age, sex and deprivation level, alongside OSAS diagnoses, among children aged <16 years who underwent (adeno)tonsillectomy in England between 2001/2 and 2011/12. RESULTS: Among children aged <16 years, there were 29,697 and 27,732 (adeno)tonsillectomies performed in 2001/2 and 2011/12, respectively. The median age at (adeno)tonsillectomy decreased from 7 (IQR: 5-11) to 5 (IQR: 4-9) years over the decade. (Adeno)tonsillectomy rates among children aged 4-15 years decreased by 14% from 350 (95%CI: 346-354) in 2001/2 to 300 (95%CI: 296-303) per 100,000 children in 2011/12. However, (adeno)tonsillectomy rates among children aged <4 years increased by 58% from 135 (95%CI: 131-140) to 213 (95%CI 208-219) per 100,000 children in 2001/2 and 2011/2, respectively. OSAS diagnoses among children aged <4 years who underwent surgery increased from 18% to 39% between these study years and the proportion of children aged <4 years with OSAS from the most deprived areas increased from 5% to 12%, respectively. CONCLUSIONS: (Adeno)tonsillectomy rates declined among children aged 4-15 years, which reflects national guidelines recommending the restriction of the operation to children with more severe recurrent throat infections. However, (adeno)tonsillectomy rates among pre-school children substantially increased over the past decade and one in five children undergoing the operation was aged <4 years in 2011/12.The increase in surgery rates in younger children is likely to have been driven by increased awareness and detection of OSAS, particularly among children from the most deprived areas

Diversity of Haloquadratum and other haloarchaea in three, geographically distant, Australian saltern crystallizer ponds

Haloquadratum walsbyi is frequently a dominant member of the microbial communities in hypersaline waters. 16S rRNA gene sequences indicate that divergence within this species is very low but relatively few sites have been examined, particularly in the southern hemisphere. The diversity of Haloquadratum was examined in three coastal, but geographically distant saltern crystallizer ponds in Australia, using both culture-independent and culture-dependent methods. Two 97%-OTU, comprising Haloquadratum- and Halorubrum-related sequences, were shared by all three sites, with the former OTU representing about 40% of the sequences recovered at each site. Sequences 99.5% identical to that of Hqr. walsbyi C23T were present at all three sites and, overall, 98% of the Haloquadratum-related sequences displayed ≤2% divergence from that of the type strain. While haloarchaeal diversity at each site was relatively low (9–16 OTUs), seven phylogroups (clones and/or isolates) and 4 different clones showed ≤90% sequence identity to classified taxa, and appear to represent novel genera. Six of these branched together in phylogenetic tree reconstructions, forming a clade (MSP8-clade) whose members were only distantly related to classified taxa. Such sequences have only rarely been previously detected but were found at all three Australian crystallizers