Intensity interferometry of single x-ray pulses from a synchrotron storage ring

We report on measurements of second-order intensity correlations at the high brilliance storage ring PETRA III using a prototype of the newly developed Adaptive Gain Integrating Pixel Detector (AGIPD). The detector recorded individual synchrotron radiation pulses with an x-ray photon energy of 14.4 keV and repetition rate of about 5 MHz. The second-order intensity correlation function was measured simultaneously at different spatial separations that allowed to determine the transverse coherence length at these x-ray energies. The measured values are in a good agreement with theoretical simulations based on the Gaussian Schell-model.Comment: 16 pages, 6 figures, 42 reference

High rates of suicide and attempted suicide using pesticides in Nickerie, Suriname, South America

Suicide and attempted suicide are identified as a serious mental health problem in Suriname, especially in the district of Nickerie. An epidemiological study in the Nickerie catchment area revealed high rates of suicide (48 per 100,000) and attempted suicide (207 per 100,000) on average in the years 2000–2004. Particularly remarkable is the high number of attempted suicides among males (49%), and the use of pesticides in both fatal (55%) and nonfatal suicidal behavior (44%). Probably this high incidence of suicidal behavior reflects the very poor economic situation of the district, poverty of most of the population, high levels of alcohol misuse, domestic violence, the rigidity of Hindustani culture regarding family traditions, the accessibility of pesticides, and the lack of future perspectives. Health care alone will not be sufficient to tackle this problem. One of the most urgent measures to prevent suicides is to stow away pesticides in locked cabinets with the key held by the proprietor

2D Detectors for Particle Physics and for Imaging Applications

The demands on detectors for particle detection as well as for medical and astronomical X-ray imaging are continuously pushing the development of novel pixel detectors. The state of the art in pixel detector technology to date are hybrid pixel detectors in which sensor and read-out integrated circuits are processed on different substrates and connected via high density interconnect structures. While these detectors are technologically mastered such that large scale particle detectors can be and are being built, the demands for improved performance for the next generation particle detectors ask for the development of monolithic or semi-monolithic approaches. Given the fact that the demands for medical imaging are different in some key aspects, developments for these applications, which started as particle physics spin-off, are becomming rather independent. New approaches are leading to novel signal processing concepts and interconnect technologies to satisfy the need for very high dynamic range and large area detectors. The present state in hybrid and (semi-)monolithic pixel detector development and their different approaches for particle physics and imaging application is reviewed

The Adaptive Gain Integrating Pixel Detector at the European XFEL

The Adaptive Gain Integrating Pixel Detector (AGIPD) is an x-ray imager, custom designed for the European x-ray Free-Electron Laser (XFEL). It is a fast, low noise integrating detector, with an adaptive gain amplifier per pixel. This has an equivalent noise of less than 1 keV when detecting single photons and, when switched into another gain state, a dynamic range of more than 10$^4$ photons of 12 keV. In burst mode the system is able to store 352 images while running at up to 6.5 MHz, which is compatible with the 4.5 MHz frame rate at the European XFEL. The AGIPD system was installed and commissioned in August 2017, and successfully used for the first experiments at the Single Particles, Clusters and Biomolecules (SPB) experimental station at the European XFEL since September 2017. This paper describes the principal components and performance parameters of the system.Comment: revised version after peer revie

The efficacy of positive psychological interventions from non-western countries: a systematic review and meta-analysis

Recently, there has been a sharply incremental number of studies of positive psychology interventions (PPIs) from non-western countries. The aim of this study is to review and evaluate the efficacy of these PPIs. Databases, including PubMed, PsycInfo, and Scopus, were searched up to December 2017. In addition, we performed hand searches and reference checks. After removal of duplicates, 7,516 studies were screened and finally 28 randomized controlled trials (RCTs) were included in the meta-analysis. A random effects model was used to calculate between group effect-sizes at post-test. Results showed that PPIs from non-western countries have a moderate effect on subjective well-being (g = 0.48) and psychological well-being (g = 0.40), and a large effect on depression (g = 0.62) and anxiety (g = 0.95). The overall low study quality of the studies indicates the possibility of biases, which may explain why PPIs from non-western countries report larger effect sizes than PPIs from western countries. However, PPIs could also be more effective in non-western countries due to a better cultural fit

Playing Snake on a Graph

Snake is a classic computer game, which has been around for decades. Based on this game, we study the game of Snake on arbitrary undirected graphs. A snake forms a simple path that has to move to an apple while avoiding colliding with itself. When the snake reaches the apple, it grows longer, and a new apple appears. A graph on which the snake has a strategy to keep eating apples until it covers all the vertices of the graph is called snake-winnable. We prove that determining whether a graph is snake-winnable is NP-hard, even when restricted to grid graphs. We fully characterize snake-winnable graphs for odd-sized bipartite graphs and graphs with vertex-connectivity 1. While Hamiltonian graphs are always snake-winnable, we show that non-Hamiltonian snake-winnable graphs have a girth of at most 6 and that this bound is tight

Children's Human Capabilities and Child Maltreatment

There are no known studies that have explored a conceptual basis for valorizing child maltreatment as a human development impediment using the Human Capability Approach. The pilot study assessed the prevalence of child maltreatment amongst 68 (N=219) school-aged children 12 – 17 years in one secondary school in Aruba using Nussbaum’s list of 10 central human capabilities. Among this sample, the prevalence of child maltreatment was at 100%. The most prevalent types of child maltreatment were emotional abuse (94.2%), physical abuse (88.4%), severe physical abuse (66.7%) and neglect (42%). Sexual abuse had the lowest prevalence rate at 18.8%. The levels of functionings achieved varied according to types of child maltreatment and their prevalence. Neglect, witnessing inter-parental violence and sexual abuse were associated with lower achievements on the combined 10 central human capabilities except for emotional abuse, physical abuse and severe physical abuse which reported highest prevalence.  These types of child maltreatment were too common and left little to no variability to calculate statistical relationships with the 10 human capabilities. These findings are disturbing and raise concerns about the normalization of abuse.  Further research is recommended to determine the contributing factors to widespread use of emotional and physical abuse and the potential for intergenerational transmission of child maltreatment. Future research is also recommended with a larger sample that may provide more meaningful analysis of the capability space of children affected by child maltreatment.No hay estudios conocidos que hayan explorado una base conceptual para valorizar al maltrato infantil como un impedimento para el desarrollo humano utilizando el Enfoque de Capacidad Humana. El estudio piloto evaluó la prevalencia del maltrato infantil entre 68 (N = 219) niños en edad escolar de 12 a 17 años en una escuela secundaria en Aruba utilizando la lista de Nussbaum de 10 capacidades humanas centrales. La prevalencia del maltrato infantil es del 100%. Los tipos de maltrato infantil más frecuentes fueron: el abuso emocional, con 94,2%, abuso físico 88,4%, abuso físico severo 66,7% y negligencia 42%. El abuso sexual tuvo la tasa de frecuencia más baja, en 18,8%. Los niveles de funcionamiento alcanzados variaron según los tipos de maltrato infantil y su prevalencia. La negligencia, presenciar la violencia entre padres y el abuso sexual se asociaron con logros más bajos entre las 10 capacidades humanas centrales combinadas, excepto el abuso emocional, el abuso físico y el abuso físico severo que tuvieron la prevalencia más alta. Estos tipos de maltrato infantil eran demasiado altos y dejaban poca o ninguna variabilidad para calcular las relaciones estadísticas con las 10 capacidades humanas. Estos hallazgos son inquietantes y generan inquietudes sobre la normalización del abuso. Se recomienda realizar más investigaciones para determinar los factores que contribuyen al uso generalizado del abuso físico y emocional y el potencial de transmisión intergeneracional del maltrato infantil. Se recomienda, además, realizar investigaciones futuras con una muestra más grande que pudiera proporcionar un análisis más significativo del espacio de capacidad de los niños afectados por el maltrato infantil