2,155 research outputs found
The hot gas content of fossil galaxy clusters
We investigate the properties of the hot gas in four fossil galaxy systems
detected at high significance in the Planck Sunyaev-Zeldovich (SZ) survey.
XMM-Newton observations reveal overall temperatures of kT ~ 5-6 keV and yield
hydrostatic masses M500,HE > 3.5 x 10e14 Msun, confirming their nature as bona
fide massive clusters. We measure the thermodynamic properties of the hot gas
in X-rays (out to beyond R500 in three cases) and derive their individual
pressure profiles out to R ~ 2.5 R500 with the SZ data. We combine the X-ray
and SZ data to measure hydrostatic mass profiles and to examine the hot gas
content and its radial distribution. The average Navarro-Frenk-White (NFW)
concentration parameter, c500 = 3.2 +/- 0.4, is the same as that of relaxed
`normal' clusters. The gas mass fraction profiles exhibit striking variation in
the inner regions, but converge to approximately the cosmic baryon fraction
(corrected for depletion) at R500. Beyond R500 the gas mass fraction profiles
again diverge, which we interpret as being due to a difference in gas clumping
and/or a breakdown of hydrostatic equilibrium in the external regions. Overall
our observations point to considerable radial variation in the hot gas content
and in the gas clumping and/or hydrostatic equilibrium properties in these
fossil clusters, at odds with the interpretation of their being old, evolved
and undisturbed. At least some fossil objects appear to be dynamically young.Comment: 4 pages, 2 figures. Accepted for publication in A&
De stem van patienten; een kaartmethode voor patientenbetrokkenheid bij translationeel onderzoek
Human immunodeficiency virus and human papilloma virus - why HPV-induced lesions do not spontaneously resolve and why therapeutic vaccination can be successful
HIV and HPV can both cause chronic infections and are acquired during sexual contact. HIV infection results in a progressive loss of CD4+ T cells that is associated with an increased prevalence of HPV infections, type-specific persistence and an increase in HPV-associated malignancies. On the one hand this illustrates the important role of HPV-specific CD4+ helper T-cell immunity, on the other it shows the Achilles heel of the HPV-specific immune response. The use of highly active antiretroviral therapy (HAART) results in a rapid reduction of HIV and a reconstitution of systemic CD4+ T-cell levels. The use of HAART thus has the potential to raise immunity to HPV but to the surprise of many, the incidence of HPV-induced diseases has increased rather than declined since the introduction of HAART. Here, the knowledge on how HPV-induced diseases develop in the face of a non-compromised immune system will be used to explain why the effect of HAART on HPV-induced diseases is modest at best. Furthermore, exciting new data in the field of therapeutic vaccines against HPV will be discussed as this may form a more durable and clinically successful therapeutic approach for the treatment of HPV-induced high-grade lesions in HIV-positive subjects on HAART
Need for uniform definitions in newborn screening for SCID: the next challenge for screeners and immunologists
During the ISNS meeting "Newborn Screening for SCID 'State of the Art'" on 26 and 27 January 2021, the topic of case definitions and related issues were discussed. There is currently a lack of uniform definitions and therefore a lack of uniform registration of screen-positive cases. This severely hampers the comparison of outcomes of different screening programs and the exchange of experiences gained by the different countries performing SCID screening, which is essential to improve screening programs. In this letter, I outline the current situation and indicate the need for uniform definitions and classification, which in my view needs to be a joined effort of screeners and immunologists.Transplantation and immunomodulatio
Student outcomes from diverse undergraduate research experiences - findings from a multi-disciplinary study
Undergraduate research experiences (UREs) provide students with opportunities to engage in high impact experiential learning. UREs have been especially prevalent in the sciences, but there are now extensive banks of case studies demonstrating the use of UREs as an educationally enriching activity in nearly all disciplines. This study investigated the diversity of UREs available across a wide range of disciplines at a large Australian research-intensive university and examined the perceived benefits. Through group interviews with 68 academics, we gathered detailed information about 81 URE activities, across 28 Schools within the institution (representing 77.8% of Schools), ranging from archaeology to political science, from biology to social work and from law to journalism. The most common URE model observed was that of activities embedded in courses. Across disciplines the most common feature was the requirement for students to engage with the research literature in their field. A smaller number of models incorporated features which allowed students to engage in other high impact learning activities such as community-based activities and internships. Although we identified a large ‘set’ of perceived student outcomes across the varied URE models the generic graduate attributes attained by students through these UREs appeared to be independent of the discipline itself. In most cases, the UREs were available to all students rather than an elite or specialist cohort. This leads us to believe that across a range of disciplinary contexts, there are many ways to use UREs to achieve high levels of engagement of large cohorts of students
Long-term care use after a stroke or femoral fracture and the role of family caregivers
Background: There has been a shift from institutional care towards home care, and from formal to informal care to
contain long-term care (LTC) costs in many countries. However, substitution to home care or informal care might
be harder to achieve for some conditions than for others. Therefore, insight is needed in differences in LTC use, and
the role of potential informal care givers, across specific conditions. We analyze differences in LTC use of previously
independent older patients after a fracture of femur and stroke, and in particular examine to what extent having a
partner and children affects LTC use for these conditions.
Methods: Using administrative data on Dutch previously independent older people (55+) with a fracture of femur
or stroke in 2013, we investigate their LTC use in the year after the condition takes place. We use administrative
treatment data to select individuals who were treated by a medical specialist for a stroke or femoral fracture in
2013. Subsequent LTC use is measured as using no formal care, home care, institutional care or being deceased at
13 consecutive four-weekly periods after initial treatment. We relate long-term care use to having a partner, having
children, other personal characteristics and the living environment.
Results: The probability to use no formal care 1 year after the initial treatment is equally high for both conditions,
but patients with a fracture are more likely to use home care, while patients with a stroke are more likely to use
institutional care or have died. Having a spouse has a negative effect on home care and institutional care use, but
the timing of the effect, especially for institutional care, differs strongly between the two conditions. Having
children also has a negative effect on formal care use, and this effect is consistently larger for patients with a
fracture than patients with a stroke.
Conclusion: As the condition and the effect of potential informal care givers matter for subsequent long-term care
use, policy makers should take the expected prevalence of specific conditions within the older people population
into account when designing long-term car
Bridging youth and gender studies to analyse rural young women and men's livelihood pathways in Central Uganda
Many development countries are currently undergoing major demographic shifts as the percentage of young people of the total population rapidly increases. This shift is associated with high rates of migration, unemployment and instability. In policy discourses, engaging youth in commercial agricultural is often presented as a measure to control or even counter these trends. In Uganda, a country with one of the youngest populations in the world, we investigated whether young people themselves see a career in farming as an option. We studied the livelihood pathways of rural-born young men and women from Central Uganda and in particular; 1) their aspirations, 2) the extent to which these aspirations are associated with agriculture, and 3) the importance of gender in shaping their opportunity spaces. Data consisted of in-depth interviews with 8 young men and 8 young women originating from the same rural community in Central Uganda (2017) and was supported by three additional datasets collected between 2010 and 2014; one qualitative case-study conducted in the same site (2014) and two survey datasets collected in three rural sites in Central Uganda in 2010 (N = 199) and 2012 (N = 54). Our findings suggest a large proportion of youth out-migrating from the rural communities, with young women migrating more often than young men. Farming was seldom an aspiration but irrespective of sex or residence most young men and women did remain engaged in agriculture in some way. The nature of the engagement was different for men and women though, with young women specifically refraining from commercial agriculture. By analyzing the opportunity space of young men and women, we uncovered how their livelihood pathways were linked to a set of normative and structural constraints maintaining gender inequality. Examples were young women's weaker resource base (land) and gender norms which discourage young women's independent commercial (agricultural) activities. To advance the engagement of young men and especially women in commercial agriculture, it is important to acknowledge these patterns and their underlying structural gender differences.</p
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