Infinitely many states and stochastic symmetry in a Gaussian Potts-Hopfield model

We study a Gaussian Potts-Hopfield model. Whereas for Ising spins and two disorder variables per site the chaotic pair scenario is realized, we find that for q-state Potts spins [{q(q-1} \over 2]-tuples occur. Beyond the breaking of a continous stochastic symmetry, we study the fluctuations and obtain the Newman-Stein metastate description for our model.Comment: latex, 17 page

"The difference that makes a difference": highlighting the role of variable contexts within an HIV Prevention Community Randomised Trial (HPTN 071/PopART) in 21 study communities in Zambia and South Africa.

This paper explores contextual heterogeneity within a community randomised trial HPTN 071 (Population Effects of Antiretroviral Treatment to Reduce HIV Transmission) carried out in 21 study communities (12 Zambian, 9 South African). The trial evaluates the impact of a combination HIV prevention package (including household-based HIV counselling and testing and anti-retroviral treatment (ART) eligibility regardless of CD4-count) on HIV incidence. The selection, matching and randomisation of study communities relied on key epidemiological and demographic variables and community and stakeholder support. In 2013, following the selection of study communities, a "Broad Brush Survey" (BBS) approach was used to rapidly gather qualitative data on each study community, prior to the implementation of the trial intervention. First-year process indicator intervention data (2014-2015) were collected during the household-based intervention by community lay workers. Using an open/closed typology of urban communities (indicating more or less heterogeneity), this qualitative inquiry presents key features of 12 Zambian communities using a list of four meta-indicators (physical features, social organisation, networks and community narratives). These indicators are then compared with four intervention process indicators in a smaller set of four study communities. The process indicators selected for this analysis indicate response to the intervention (uptake) amongst adults. The BBS qualitative data are used to interpret patterns of similarity and variability in the process indicators across four communities. We found that meta-indicators of local context helped to interpret patterns of similarity and variability emerging across and within the four communities. Features especially significant for influencing heterogeneity in process indicators include proportion of middle-class residents, proximity to neighbouring communities and town centre, the scale of the informal economy, livelihood-linked mobility, presence of HIV stakeholders over time and commitment to community action. Future interdisciplinary analysis is needed to explore if these patterns of difference continue to hold up over the full intervention period and all intervention communities

High-Latitude HI in the Low Surface Brightness Galaxy UGC7321

From the analysis of sensitive HI 21-cm line observations, we find evidence for vertically extended HI emission (|z|<~2.4 kpc) in the edge-on, low surface brightness spiral galaxy UGC7321. Three-dimensional modelling suggests that the HI disk of UGC7321 is both warped and flared, but that neither effect can fully reproduce the spatial distribution and kinematics of the highest z-height gas. We are able to model the high-latitude emission as an additional HI component in the form of a ``thick disk'' or ``halo'' with a FWHM~3.3 kpc. We find tentative evidence that the vertically extended gas declines in rotational velocity as a function of z, although we are unable to completely rule out models with constant V(z). In spite of the low star formation rate of UGC7321, energy from supernovae may be sufficient to sustain this high-latitude gas. However, alternative origins for this material, such as slow, sustained infall, cannot yet be excluded.Comment: to appear in the August 20 Astrophysical Journal; 17 pages; version with full resolution figures available at http://cfa-www.harvard.edu/~lmatthew

Liefde voor het Openbaar Bestuur en Liefde voor de Bestuurskunde

Arthur Ringeling heeft in zijn afscheidsrede van 28 september 2007 aan de Erasmus Universiteit Rotterdam een terugblik gegeven op de langdurige studiereis die hij op het vakgebied der bestuurskunde heeft afgelegd. Zijn academische studiereis in de bestuurskunde nam een aanvang met zijn studie politicologie aan de Vrije Universiteit van Amsterdam, welke hij in 1969 afrondde. Daarna verhuisde de protestantse Amsterdammer naar het katholieke Zuiden om aan de katholieke Universiteit van Nijmegen wetenschappelijk medewerker te worden en in 1978 met succes een proefschrift te verdedigen over ‘beleidsvrijheid van ambtenaren’. In 1981 werd hij benoemd tot hoogleraar aan de Erasmus Universiteit Rotterdam, waar hij in 1983 zijn oratie uitsprak met de titel ‘De Instrumenten van het Beleid’. In 1987 was hij betrokken bij het onderzoek van de parlementaire enquêtecommissie rond de paspoortaffaire. In 1992 verbleef hij een ‘sabbatical year’ op de School of Public and Environmental Affairs (SPEA) aan de Indiana University te Bloomington. In 1993 publiceerde hij zijn bekende boek ‘Het imago van de overheid’. En zoals we hierna zullen zien, ondernam hij daarna nog allerlei activiteiten die hem tot een bestuurskundige maakten die zowel in de wetenschap als de praktijk van het Nederlandse openbaar bestuur naam en faam heeft gemaakt

Online One-Stop Shop for Disaster Response Services After the MH17 Airplane Crash:An Evaluation Study

Background: A one-stop shop for disaster response services provides a central location for information and advice in an accessible way. Yet little is known about its organization and outcomes. After the MH17 airplane crash, the one-stop shop concept was realized through a digital environment called the Information and Referral Center (IRC). The aim of this study was to evaluate the experiences of users and providers in regard to the IRC and to identify improvement points for future IRCs. Method: Data was collected among affected ones as well as involved organizations, using interviews, focus groups, surveys and online user information. Existing evaluation and quality models were combined to design the study and analyze the data. Results: First, affected ones and a variety of organizations involved were positive about the merits of the IRC. Affected ones indicated they perceived the IRC as a reliable source of information and appreciated the referral possibilities. Second, the feature of the IRC to serve as a community where affected ones could meet, share experiences and support each other was hardly used according to participants. Lastly, tracking evolving psychosocial needs and problems through the IRC was hampered due to difficulty in accessing relevant data. Conclusions: The IRC helped organizations to structure and align their services. Affected ones were positive about its reliability and accessibility. An IRC has to be embedded within the established care structures. Future research could indicate whether an IRC is useful in other event types and population contexts as well

T cell receptor sequence clustering and antigen specificity

There has been increasing interest in the role of T cells and their involvement in cancer, autoimmune and infectious diseases. However, the nature of T cell receptor (TCR) epitope recognition at a repertoire level is not yet fully understood. Due to technological advances a plethora of TCR sequences from a variety of disease and treatment settings has become readily available. Current efforts in TCR specificity analysis focus on identifying characteristics in immune repertoires which can explain or predict disease outcome or progression, or can be used to monitor the efficacy of disease therapy. In this context, clustering of TCRs by sequence to reflect biological similarity, and especially to reflect antigen specificity have become of paramount importance. We review the main TCR sequence clustering methods and the different similarity measures they use, and discuss their performance and possible improvement. We aim to provide guidance for non-specialists who wish to use TCR repertoire sequencing for disease tracking, patient stratification or therapy prediction, and to provide a starting point for those aiming to develop novel techniques for TCR annotation through clustering