Infrared Diameter of IRC+10216 Determined from Lunar Occultations

Lunar occultations of IRC+10216 have been used to determine the size of the regions emitting 2.2-, 3.5-, 4.8-, and 10-μ radiation. The results are interpreted as the first direct measurement of the physical size of a dust shell surrounding a late-type star

Ceramic Paste for Patching High-Temperature Insulation

A ceramic paste that can be applied relatively easily, either by itself or in combination with one or more layer(s) of high-temperature ceramic fabrics, such as silicon carbide or zirconia, has been invented as a means of patching cracks or holes in the reinforced carbon-carbon forward surfaces of a space shuttle in orbit before returning to Earth. The paste or the paste/fabric combination could also be used to repair rocket-motor combustion chambers, and could be used on Earth to patch similar high-temperature structures. The specified chemical composition of the paste admits of a number of variations, and the exact proportions of its constituents are proprietary. In general, the paste consists of (1) silicon carbide, possibly with addition of (2) hafnium carbide, zirconium carbide, zirconium boride, silicon tetraboride, silicon hexaboride, or other metal carbides or oxides blended with (3) a silazane-based polymer. Because the paste is viscous and sticky at normal terrestrial and outer-space ambient temperatures, high-temperature ceramic fabrics such as silicon carbide or zirconia fabric impregnated with the paste (or the paste alone) sticks to the damaged surface to which it is applied. Once the patch has been applied, it is smoothed to minimize edge steps as required [forward-facing edge steps must be < or equal to 0.030 in. (< or equal to 0.76 mm) in the original intended space-shuttle application]. The patch is then heated to a curing temperature thereby converting it from a flexible material to a hard, tough material. The curing temperature is 375 to 450 F (approx.190 to 230 C). In torch tests and arc-jet tests, the cured paste was found to be capable of withstanding a temperature of 3,500 F (approx. 1,900 C) for 15 minutes. As such, the material appears to satisfy the requirement, in the original space-shuttle application, to withstand re-entry temperatures of approx.3,000 F (approx. 1,600 C)

Genetic Variants and Related Biomarkers in Sporadic Alzheimer's Disease.

From a neuropathological perspective, elderly patients who die with a clinical diagnosis of sporadic Alzheimer's disease (AD) are a heterogeneous group with several different pathologies contributing to the AD phenotype. This poses a challenge when searching for low effect size susceptibility genes for AD. Further, control groups may be contaminated by significant numbers of preclinical AD patients, which also reduces the power of genetic association studies. Here, we discuss how cerebrospinal fluid and imaging biomarkers can be used to increase the chance of finding novel susceptibility genes and as a means to study the functional consequences of risk alleles

Intergenerational residential school attendance and increased substance use among First Nation adults living off-reserve: An analysis of the aboriginal peoples survey 2017

IntroductionThe Truth and Reconciliation Commission of Canada (TRCC) published 94 Calls to Action in 2015 to address long-term, intergenerational effects of the residential school system, highlighting the pervasive impact of colonialism on the wellbeing of Indigenous peoples in Canada. Indeed, research with Indigenous populations in Canada has captured that prior experiences of residential schools contributes to the intergenerational transmission of mental and physical health disparities. Despite these studies, further research is needed that contextualizes the influence of residential schools within broader frameworks that consider Indigenous social determinants of health in Canada. As such, the purpose of the present study was to examine patterns of substance use and mental and physical health among individuals with a history of residential school attendance (RSA) and individuals reporting parent or two-generation (parent and grandparent) RSA.MethodData from the Aboriginal Peoples Survey (2017), involving 10,030 First Nations individuals living off reserve, were analyzed.ResultsSelf-reported mental and physical health scores were significantly lower among those had attended residential schools, whose parents attended residential schools, and whose grandparents attended residential schools, when compared to those who did not. Further, family RSA was associated with increased substance use among participants, though the findings were variable based on sex and specific substance analyzed. Meanwhile, individual and family RSA was not associated with increased likelihood of a mental health diagnosis.DiscussionThese findings provide additional support for how both parental and two-generation family histories of RSA are associated with individual physical and mental health outcomes. Further, these findings articulate the need for the TRCC's Calls to Action to be actually implemented, including community-based approaches that harness the strength of Indigenous people and communities who aim to close the gap in these health disparities for their children and families

Ageing, masculinity and Parkinson's disease: Embodied perspectives

Parkinson&rsquo;s Disease (PD) presents as an illness which predominantly affects older men. However older men&rsquo;s lived experiences of PD, including how they are influenced by age and gender relations has seen little empirical study. Drawing on Watson&rsquo;s (2000) male body schema, this paper explores PD&rsquo;s effects on men&rsquo;s bodies, alongside how men engage with masculinities and ageing in order to make meaning from these experiences. Data is presented from 30 narrative and semi structured interviews with 15 men of various ages who were living with PD. Findings suggest that PD threatens a pragmatic embodiment expressed through men&rsquo;s everyday occupations; a visceral embodiment located in difficulties with the body&rsquo;s basic movements and intimate functions and an experiential embodiment concerned with emotions and sensations within and about the body. In addition, each dimension of men&rsquo;s embodiment also intersected with the ageing process, a process also shaped in turn by broader social and cultural concerns regarding the positions and possibilities of men&rsquo;s lives as they move through the life course. This paper concludes by discussing the implications of gender and ageing in understanding men&rsquo;s experiences of PD

Strong damping of phononic heat current by magnetic excitations in SrCu_2(BO_3)_2

Measurements of the thermal conductivity as a function of temperature and magnetic field in the 2D dimer spin system SrCu$_2$(BO$_3$)$_2$ are presented. In zero magnetic field the thermal conductivity along and perpendicular to the magnetic planes shows a pronounced double-peak structure as a function of temperature. The low-temperature maximum is drastically suppressed with increasing magnetic field. Our quantitative analysis reveals that the heat current is due to phonons and that the double-peak structure arises from pronounced resonant scattering of phonons by magnetic excitations.Comment: a bit more than 4 pages, 2 figures included; minor changes to improve the clarity of the presentatio

Climate change curricula for adult audiences in agriculture and forestry: A review

Agricultural and forestry advisers and other technical service providers play an important role in supporting farmers and foresters to adapt to climate change. However, not all agricultural and forestry advisers are comfortable talking about climate change with land managers. While there is a demonstrated interest related to climate related professional development, few examples of curricula developed with the express purpose of serving this audience and a systematic review of these curricula has not been conducted. To address this gap, we reviewed 12 curricula which were developed and implemented between 2001 and 2017. The goal of this review is to apply the lessons learned from a range of climate change-focused curricula to new, regionally or sector-specific educational programs targeting both agricultural advisers and innovative farmers. Our findings suggest that developers of future educational programs consider the following: (a) the specific needs of their audience, including topical interests and learning needs; (b) the use of interdisciplinary teams for curricula development; (c) trade-offs associated with inclusivity and depth of course content; and (d) the advantages of project-based education approaches suited for adult learning audiences. By applying these concepts to future curricula, these curricula are likely to have the greatest level of impact