A study on the thermal conductivity of compacted bentonites

Thermal conductivity of compacted bentonite is one of the most important properties in the design of high-level radioactive waste repositories where this material is proposed for use as a buffer. In the work described here, a thermal probe based on the hot wire method was used to measure the thermal conductivity of compacted bentonite specimens. The experimental results were analyzed to observe the effects of various factors (i.e. dry density, water content, hysteresis, degree of saturation and volumetric fraction of soil constituents) on the thermal conductivity. A linear correlation was proposed to predict the thermal conductivity of compacted bentonite based on experimentally observed relationship between the volumetric fraction of air and the thermal conductivity. The relevance of this correlation was finally analyzed together with others existing methods using experimental data on several compacted bentonites

The analysis of longitudinal quality of life measures with informative drop-out: a pattern mixture approach

The analysis of longitudinal health-related quality of life measures (HRQOL) can be seriously hampered due to informative drop-out. Random effects models assume Missing At Random and do not take into account informative drop-out. We therefore aim to correct the bias due to informative drop-out. Analyses of data from a trial comparing standard-dose and high-dose chemotherapy for patients with breast cancer with respect to long-term impact on HRQOL will serve as illustration. The subscale Physical Function (PF) of the SF36 will be used. A pattern mixture approach is proposed to account for informative drop-out. Patterns are defined based on events related to HRQOL, such as death and relapse. The results of this pattern mixture approach are compared to the results of the commonly used random effects model. The findings of the pattern mixture approach are well interpretable, and different courses over time in different patterns are distinguished. In terms of estimated differences between standard dose and high dose, the results of both approaches are slightly different, but have no consequences for the clinical evaluation of both doses. Under the assumption that drop-out is at random within the patterns, the pattern mixture approach adjusts the estimates to a certain degree. This approach accounts in a relatively simple way for informative drop-out

A Sample of Ultra Steep Spectrum Sources Selected from the Westerbork In the Southern Hemisphere (WISH) survey

The 352 MHz Westerbork In the Southern Hemisphere (WISH) survey is the southern extension of the WENSS, covering 1.60 sr between -9 < DEC < -26 to a limiting flux density of ~18 mJy (5sigma). Due to the very low elevation of the observations, the survey has a much lower resolution in declination than in right ascension (54" x 54"cosec(DEC)). A correlation with the 1.4 GHz NVSS shows that the positional accuracy is less constrained in declination than in right ascension, but there is no significant systematic error. We present a source list containing 73570 sources. We correlate this WISH catalogue with the NVSS to construct a sample of faint Ultra Steep Spectrum (USS) sources, which is accessible for follow-up studies with large optical telescopes in the southern hemisphere. This sample is aimed at increasing the number of known high redshift radio galaxies to allow detailed follow-up studies of these massive galaxies and their environments in the early Universe.Comment: 12 Pages, including 5 PostScript figures. Accepted for publication in Astronomy & Astrophysics. The full WISH catalog with 73570 sources is available from http://www.strw.leidenuniv.nl/wenss

Both perimenstrual and nonperimenstrual migraine days respond to anti-calcitonin gene-related peptide (receptor) antibodies

Background and purpose: Anti-calcitonin gene-related peptide (CGRP) (receptor) antibodies effectively reduce overall migraine attack frequency, but whether there are differences in effect between perimenstrual and nonperimenstrual migraine days has not been investigated. Methods: We performed a single-arm study among women with migraine. Participants were followed with electronic E-diaries during one (pretreatment) baseline month and 6 months of treatment with either erenumab or fremanezumab. Differences in treatment effect on perimenstrual and nonperimenstrual migraine days were assessed using a mixed effects logistic regression model, with migraine day as dependent variable; treatment, menstrual window, and an interaction term (treatment × menstrual window) as fixed effects; and patient as a random effect. Results: There was no interaction between the menstrual window and treatment effect, indicating that the reduction in migraine days under treatment was similar during the menstrual window and the remainder of the menstrual cycle (odds ratio for treatment = 0.44, 95% confidence interval = 0.38–0.51). Conclusions: Our findings support prophylactic use of anti-CGRP (receptor) antibodies for women with menstrual migraine, as this leads to consistent reductions in number of migraine days during the entire menstrual cycle.</p

A catalogue of damped Lyman alpha absorption systems and radio flux densities of the background quasars

We present a catalogue of the 322 damped Lyman alpha absorbers taken from the literature. All damped Lyman alpha absorbers are included, with no selection on redshift or quasar magnitude. Of these, 123 are candidates and await confirmation using high resolution spectroscopy. For all 322 objects we catalogue the radio properties of the background quasars, where known. Around 60 quasars have radio flux densities above 0.1 Jy and approximately half of these have optical magnitudes brighter than V = 18. This compilation should prove useful in several areas of extragalactic/cosmological research.Comment: 26 Pages, 12 PS tables, 1 embedded table. Accepted by PASA. Continuously updated online catalogue available at http://www.phys.unsw.edu.au/~sjc/dl

Mid-term results of the Latitude primary total elbow arthroplasty

Background: The Latitude total elbow prosthesis is a third-generation implant, developed to restore the natural anatomy of the elbow. Literature on this prosthesis is scarce. The aim of this study was to analyze the mid-term results of the Latitude total elbow prosthesis. Methods: We retrospectively evaluated 62 patients (21 men and 41 women). The mean age at the time of surgery was 65 years (range, 28-87 years). The main indication for surgery was inflammatory arthritis. The outcome measures were complications, reoperations, self-reported physical functioning, pain, satisfaction, objectively measured physical functioning, and radiologic signs of loosening. Kaplan-Meier survival analysis was used to determine survival with revision as the endpoint. Results: Sixty-nine primary Latitude prostheses were placed in 62 patients between 2008 and 2019. Six patients (7 prostheses) died, 3 elbows underwent revision, and 9 patients were lost to follow-up. A total of 44 patients (50 prostheses) were available for follow-up. The mean length of follow-up was 51 months (range, 10-144 months). Kaplan-Meier survival analysis showed a survival rate of 82% at 10 years after surgery. The main reason for revision was aseptic loosening. Radial head dissociation was seen in 8 patients (24%), but none had complaints. Self-reported and objectively measured physical functioning yielded good results, although 23 patients (46%) did show radiolucent lines on radiographs. Conclusion: Latitude total elbow arthroplasty is considered a successful procedure with low pain scores, high patient satisfaction, and good physical functioning. Survival rates nonetheless remain low and complication rates remain high yet are comparable to those of other elbow arthroplasties. We recommend biomechanical studies to concentrate on specific postoperative loading instructions to minimize wear and consequent loosening

Flat-spectrum symmetric objects with ~1 kpc sizes I. The candidates

In order to understand the origin and evolution of radio galaxies, searches for the youngest such sources have been conducted. Compact-medium symmetric objects (CSO-MSOs) are thought to be the earliest stages of radio sources, with possible ages of <10^3 yrs for CSOs (<1 kpc in size) and 10^4-10^5 yrs for MSOs (1-15 kpc). From a literature selection in heterogeneous surveys, we have established a sample of 37 confirmed CSOs. In addition, we only found three confirmed flat-spectrum MSOs in the literature. The typical CSO resides on a z<0.5 galaxy, has a flat radio spectrum (a_thin<0.5; S_v proportional to v^-a), is <0.3 kpc in size, has an arm length ratio <2, and well-aligned (theta<20 deg) opposite lobes with a flux density ratio <10. In order to populate the 0.3-1 kpc size range (large CSOs) and also in order to find more flat-spectrum MSOs, we have built a sample of 157 radio sources with a_{1.40}^{4.85}<0.5 that were resolved with the VLA-A 8.4 GHz. As first results, we have 'rediscovered' nine of the known CSO/MSOs while identifying two new ~14 kpc MSOs and two candidate CSO/MSOs (which only lack redshifts for final classification). We were able to reject 61 of the remaining 144 objects from literature information alone. In the series of papers that starts with this one we plan to classify the remaining 83 CSO/MSO candidates (thanks to radio and optical observations) as well as characterize the physical properties of the (likely) many 0.3-15 kpc flat-spectrum CSO/MSOs to be found.Comment: 19 pages, 14 figures, 6 tables (note that Table 2, in landscape format, has a separate file); accepted by MNRA

Alcohol and Brain Development in Adolescents and Young Adults: A Systematic Review of the Literature and Advisory Report of the Health Council of the Netherlands

Young people, whose brains are still developing, might entail a greater vulnerability to the effects of alcohol consumption on brain function and development. A committee of experts of the Health Council of the Netherlands evaluated the state of scientific knowledge regarding the question whether alcohol negatively influences brain development in young people. A systematic literature search for prospective studies was performed in PubMed and PsychINFO, for longitudinal studies of adolescents or young adults ranging between 12 and 24 y of age at baseline, investigating the relation between alcohol use and outcome measures of brain structure and activity, cognitive functioning, educational achievement, or alcohol use disorder (AUD), with measures at baseline and follow-up of the outcome of interest. Data were extracted from original articles and study quality was assessed using the Newcastle-Ottawa Scale. A total of 77 studies were included, 31 of which were of sufficient quality in relation to the study objectives. There were indications that the gray matter of the brain develops abnormally in young people who drink alcohol. In addition, the more often young people drink or the younger they start, the higher the risk of developing AUD later in life. The evidence on white matter volume or quality, brain activity, cognitive function, and educational achievement is still limited or unclear. The committee found indications that alcohol consumption can have a negative effect on brain development in adolescents and young adults and entails a risk of later AUD. The committee therefore considers it a wise choice for adolescents and young adults not to drink alcohol.Clinical epidemiolog