Comparison of small‑angle neutron and X‑ray scattering for studying cortical bone nanostructure

In this study, we present a combined small-angle neutron and X-ray scattering (SANS and SAXS) study of the nanoscale structure of cortical bone specimens from three different species. The variation of the scattering cross section of elements across the periodic table is very different for neutrons and X-rays. For X-rays, it is proportional to the electron density while for neutrons it varies irregularly with the atomic number. Hence, combining the two techniques on the same specimens allows for a more detailed interpretation of the scattering patterns as compared to a single-contrast experiment. The current study was performed on bovine, porcine and ovine specimens, obtained in two perpendicular directions with respect to the main axis of the bone (longitudinal and radial) in order to maximise the understanding of the nanostructural organisation. The specimens were also imaged with high resolution micro-computed tomography (micro-CT), yielding tissue mineral density and microstructural orientation as reference. We show that the SANS and SAXS patterns from the same specimen are effectively identical, suggesting that these bone specimens can be approximated as a two-component composite material. Hence, the observed small-angle scattering results mainly from the mineral-collagen contrast, apart from minor features associated with the internal collagen structure

Better long-term survival in young and middle-aged women than in men after a first myocardial infarction between 1985 and 2006. an analysis of 8630 patients in the Northern Sweden MONICA Study

<p>Abstract</p> <p>Background</p> <p>There is conflicting and only scant evidence on the effect of gender on long-term survival after a myocardial infarction (MI). Our aim was to analyse sex-specific survival of patients for up to 23 years after a first MI in northern Sweden and to describe time trends.</p> <p>Methods</p> <p>The Northern Sweden MONICA Myocardial Infarction Registry was linked to The Swedish National Cause of Death Registry for a total of 8630 patients, 25 to 64 years of age, 6762 men and 1868 women, with a first MI during 1985-2006. Also deaths before admission to hospital were included. Follow-up ended on August 30, 2008.</p> <p>Results</p> <p>Median follow-up was 7.1 years, maximum 23 years and the study included 70 072 patient-years. During the follow-up 45.3% of the men and 43.7% of the women had died. Median survival for men was 187 months (95% confidence interval (CI) 179-194) and for women 200 months (95% CI 186-214). The hazard ratio (HR) for all cause mortality after adjustment for age group was 1.092 (1.010-1.18, <it>P </it>= 0.025) for females compared to males, <it>i.e</it>. 9 percent higher survival in women. After excluding subjects who died before reaching hospital HR declined to 1.017 (95%CI 0.93-1.11, <it>P </it>= 0.7). For any duration of follow-up a higher proportion of women were alive, irrespective of age group. The 5-year survivals were 75.3% and 77.5%, in younger (<57 years) men and women and were 65.5% and 66.3% in older (57-64 years) men and women, respectively. For each of four successive cohorts survival improved. Survival time was longer for women than for men in all age groups.</p> <p>Conclusions</p> <p>Age-adjusted survival was higher among women than men after a first MI and has improved markedly and equally in both men and women over a 23-year period. This difference was due to lower risk for women to die before reaching hospital.</p

Evaluation of composition and mineral structure of callus tissue in rat femoral fracture.

ABSTRACT. Callus formation is a critical step for successful fracture healing. Little is known about the molecular composition and mineral structure of the newly formed tissue in the callus. The aim was to evaluate the feasibility of small angle x-ray scattering (SAXS) to assess mineral structure of callus and cortical bone and if it could provide complementary information with the compositional analyses from Fourier transform infrared (FTIR) microspectroscopy. Femurs of 12 male Sprague-Dawley rats at 9 weeks of age were fractured and fixed with an intramedullary 1.1 mm K-wire. Fractures were treated with the combinations of bone morphogenetic protein-7 and/or zoledronate. Rats were sacrificed after 6 weeks and both femurs were prepared for FTIR and SAXS analysis. Significant differences were found in the molecular composition and mineral structure between the fracture callus, fracture cortex, and control cortex. The degree of mineralization, collagen maturity, and degree of orientation of the mineral plates were lower in the callus tissue than in the cortices. The results indicate the feasibility of SAXS in the investigation of mineral structure of bone fracture callus and provide complementary information with the composition analyzed with FTIR. Moreover, this study contributes to the limited FTIR and SAXS data in the field

School absenteeism among students in Germany, Japan, Sweden, and the United Kingdom:

School absenteeism is a challenge in many countries. Still, there are few comparisons between countries, which is partly due to a lack of shared definitions of concepts. This article makes use of PISA data to compare self-reported student absenteeism in Germany, Japan, Sweden, and the United Kingdom (UK). Three data sets are used, from 2012, 2015, and 2018. The self-reported absenteeism, which is referred to as truancy in the PISA studies, was measured as having skipped a whole school day at least once in the two full weeks before students completed the PISA student questionnaire. The results show great variation between the studied countries, from 24.4% in the UK in 2015 to 1.5% in Japan in 2012. The percentage of students who reported having skipped school is much higher in the UK than in the other three countries. The differences between the countries concerning the percentage of students reporting having been absent from school are significant for all years, except between Sweden and Germany in 2015. Germany and the UK have a similar pattern in development, with the highest percentages in 2015, while Sweden and Japan have small (albeit not significant) increases from 2012 to 2018. The UK is the only country where the changes between 2012 and 2015 as well as between 2015 and 2018 were significant. It is not possible to see any obvious patterns between the countries that might be linked to differences related to their welfare regimes, education systems, or values. To find such patterns, it may be necessary either to include more countries in a study or to conduct more in-depth studies on each country

Våld mot vårdare i sjukhemsvård

This thesis aimed to explore factors related to the prevalence of violence towards caregivers working in a nursing home context. The aim was also to describe caregivers’ perceptions and experiences of violence in a nursing home context. The thesis comprises four studies. Study I includes data regarding environmental and organizational factors, residents’ and caregivers’ characteristics, and violence. Data concerning job satisfaction and working climate were also obtained. In study II, questionnaires were used to collect data concerning caregivers’ exposure to violence and their personal characteristics. Data concerning personality traits, coping resources, and burnout were collected by means of instruments. In order to illuminate caregivers’ perceptions of violence (III) and experiences of being exposed to violence (IV) interviews were performed. Quantitative data were analyzed by means of comparative and descriptive statistics. The interviews were transcribed and interpreted using a qualitative content analysis method. The results showed that 15 percent of the residents exhibited violent behaviour during the week of in-vestigation. A significant higher proportion of male residents were assessed by the caregivers to present violent behaviour compared to female residents. A discriminate analysis showed that the prevalence of behavioural symptoms and psychiatric symptoms, residents needing assistance with dressing, the caregivers’ psychological workload, and job satisfaction were the strongest discriminators between nursing home wards with a high versus low proportion of residents with violent behaviour (I). The results from study II showed that among the 196 caregivers participating in the study, 68 % re-ported exposure to violence during the previous year. Twenty-two percent reported exposure several times per week, and 51 % reported exposure at least once during the previous month. A higher proportion of caregivers 50 years or younger were exposed to violence compared to older caregivers. A higher proportion of caregivers with a work experience of three years or more reported exposure to violence compared to less experienced caregivers. A higher proportion caregivers who reported exposure to violence assessed symptoms on burnout and motherly rejection. No significant differences between the two groups were found concerning coping resources, defence mechanisms, temperament, and character. Study III showed that caregivers’ perceptions of violence are subjective and in the eye of the beholder. The caregivers perceive violence as challenging and expressed that caring situations had to be solved even though their own safety is perceived to be in danger. The caregivers perceive violence as intentional when the residents are judged to have a good cognitive capacity and are perceived to be conscious. However, the care-givers perceive violence as excusable when the residents are described as old and sick. The caregivers perceive violence as ordinary and as a part of the work situation. The caregivers also perceive violence as contextual since similar violence is accepted at the work place but not outside it. The result from study IV showed that the caregivers’ experiences of exposure to violence range be-tween being overwhelmed by contradictory emotions and being resigned. The caregivers have preconceived ideas towards the violent behaviour and describe being on guard in order to avoid being exposed to violence. The caregivers experience that they lose the control over a violent situation and strive to regain the control. They are overwhelmed by emotions such as surprise, anger, and repulsiveness and describe a resignation hav-ing to care for violent residents. Caring for violent residents is described as a constant struggle and the care-givers express a disappointment over insufficient support. The caregivers strive to regain the control by means of seeking excuses for the violent behaviour or by support from colleagues. The conclusions from this thesis are that the prevalence of violence is related to factors among the residents as well as the caregivers, that caregivers’ perceptions of violence are subjective and caregivers’ experi-ences varies between being overwhelmed by contradictory emotions and resignation. There is a risk that vio-lence in nursing homes becomes a norm, is accepted, and in this way is maintained. The boundary between what is acceptable and what is not acceptable becomes erased, the caregiver resigns, and the violence is not looked upon as a divergence but becomes a part of the working situation. It is therefore important that the problems with violence at nursing homes are attended to and that the caregivers are supported in their work