Qualification Tests of the R11410-21 Photomultiplier Tubes for the XENON1T Detector

The Hamamatsu R11410-21 photomultiplier tube is the photodetector of choice for the XENON1T dual-phase time projection chamber. The device has been optimized for a very low intrinsic radioactivity, a high quantum efficiency and a high sensitivity to single photon detection. A total of 248 tubes are currently operated in XENON1T, selected out of 321 tested units. In this article the procedures implemented to evaluate the large number of tubes prior to their installation in XENON1T are described. The parameter distributions for all tested tubes are shown, with an emphasis on those selected for XENON1T, of which the impact on the detector performance is discussed. All photomultipliers have been tested in a nitrogen atmosphere at cryogenic temperatures, with a subset of the tubes being tested in gaseous and liquid xenon, simulating their operating conditions in the dark matter detector. The performance and evaluation of the tubes in the different environments is reported and the criteria for rejection of PMTs are outlined and quantified.Comment: 24 pages, 16 figure

Acceptability of new formulations of Corn-Soy Blends and Lipid-based Nutrient Supplements in Province du Passoré, Burkina Faso

The objective of this study was to evaluate the acceptability of new formulations of six corn-soy blended flours (CSB) and six lipid-based nutrient supplements (LNS) with different quantities of milk and qualities of soy to be used for the treatment of moderate acute malnutrition (MAM). Furthermore, we wanted to explore the acceptability of foods currently used for the prevention and treatment of malnutrition in Burkina Faso to identify possible barriers that could affect the acceptability of the new formulations of supplementary foods. The study was carried out prior to a randomized controlled trial evaluating the effectiveness of these new formulations. The study involved an observed test-meal and a three-day take-home ration of the experimental food supplements to 6-30-months-old healthy children, followed by questionnaire-based interviews about the acceptability of these supplements. Interviews and focus group discussions were carried out to explore the acceptability of foods currently used for the prevention and treatment of malnutrition. The results suggest that both LNS and CSB products with different quantities of milk and qualities of soy are equally well accepted among healthy children in rural Burkina Faso based on general appreciation of the supplements and organoleptic properties. All experimental foods received good ratings and there was no significant difference between the foods. However, after the take-home ration, 58% of participants receiving CSB reported having left-overs at the end of the day compared to 37% (n=33) of the participants receiving LNS (p=0.004), suggesting that CSB was not as readily consumed as LNS. Yet, both CSB and LNS products were perceived as easy to administer and the frequency of feeding was estimated to be adequate. The study also found that similar foods, used for the prevention and treatment of malnutrition, were well appreciated in the study location. LNS were to a higher degree associated with medicine or foods with medicinal properties, but both LNS and CSB were perceived as beneficial to child health

Matriarchy in Bronze Age Crete

"Matriarchy in Bronze Age Crete: A Perspective from Archaeomythology and Modern Matriarchal Studies offers a very different perspective of Crete than is usually found in academic writing; making a compelling case for a matriarchal Bronze Age Crete. Bronze Age Crete evokes for many the image of an exceptionally sophisticated civilization: peaceful, artistic, and refined; a society in which women were highly visible and important, and the supreme deity was a Goddess. Yet, despite the fact that authorities acknowledge that the preeminent deity of Crete was a Female Divine, and that women played a major role in Cretan society, there is a gap in the scholarly literature, and a lively, ongoing debate regarding the centrality of women and the existence of matriarchy in Bronze Age Crete. The purpose of this work is to fill that gap, and to advance the debate over whether or not ancient Crete was a woman-centered and matriarchal society toward a more complex, detailed, and certain conclusion. To that end this publication utilises the field of modern matriarchal studies, with its carefully elucidated definition of the term matriarchy, and employs the methodology of archaeomythology – the use of historical, mythological, linguistic, and folkloric as well as archaeological sources. Given its scope, the volume will be of interest to scholars and students in the fields encompassed by archaeomythology, as well as the fields of women’s studies, women’s history, women’s spirituality, and modern matriarchal studies.

Removing krypton from xenon by cryogenic distillation to the ppq level

The XENON1T experiment aims for the direct detection of dark matter in a cryostat filled with 3.3 tons of liquid xenon. In order to achieve the desired sensitivity, the background induced by radioactive decays inside the detector has to be sufficiently low. One major contributor is the $\beta$-emitter $^{85}$Kr which is an intrinsic contamination of the xenon. For the XENON1T experiment a concentration of natural krypton in xenon $\rm{^{nat}}$Kr/Xe < 200 ppq (parts per quadrillion, 1 ppq = 10$^{-15}$ mol/mol) is required. In this work, the design of a novel cryogenic distillation column using the common McCabe-Thiele approach is described. The system demonstrated a krypton reduction factor of 6.4$\cdot$10$^5$ with thermodynamic stability at process speeds above 3 kg/h. The resulting concentration of $\rm{^{nat}}$Kr/Xe < 26 ppq is the lowest ever achieved, almost one order of magnitude below the requirements for XENON1T and even sufficient for future dark matter experiments using liquid xenon, such as XENONnT and DARWIN

Genome-wide study of association and interaction with maternal cytomegalovirus infection suggests new schizophrenia loci.

Genetic and environmental components as well as their interaction contribute to the risk of schizophrenia, making it highly relevant to include environmental factors in genetic studies of schizophrenia. This study comprises genome-wide association (GWA) and follow-up analyses of all individuals born in Denmark since 1981 and diagnosed with schizophrenia as well as controls from the same birth cohort. Furthermore, we present the first genome-wide interaction survey of single nucleotide polymorphisms (SNPs) and maternal cytomegalovirus (CMV) infection. The GWA analysis included 888 cases and 882 controls, and the follow-up investigation of the top GWA results was performed in independent Danish (1396 cases and 1803 controls) and German-Dutch (1169 cases, 3714 controls) samples. The SNPs most strongly associated in the single-marker analysis of the combined Danish samples were rs4757144 in ARNTL (P=3.78 × 10(-6)) and rs8057927 in CDH13 (P=1.39 × 10(-5)). Both genes have previously been linked to schizophrenia or other psychiatric disorders. The strongest associated SNP in the combined analysis, including Danish and German-Dutch samples, was rs12922317 in RUNDC2A (P=9.04 × 10(-7)). A region-based analysis summarizing independent signals in segments of 100 kb identified a new region-based genome-wide significant locus overlapping the gene ZEB1 (P=7.0 × 10(-7)). This signal was replicated in the follow-up analysis (P=2.3 × 10(-2)). Significant interaction with maternal CMV infection was found for rs7902091 (P(SNP × CMV)=7.3 × 10(-7)) in CTNNA3, a gene not previously implicated in schizophrenia, stressing the importance of including environmental factors in genetic studies

Matriarchy in Bronze Age Crete

Matriarchy in Bronze Age Crete: A Perspective from Archaeomythology and Modern Matriarchal Studies offers a very different perspective of Crete than is usually found in academic writing; making a compelling case for a matriarchal Bronze Age Crete.Bronze Age Crete evokes for many the image of an exceptionally sophisticated civilization: peaceful, artistic, and refined; a society in which women were highly visible and important, and the supreme deity was a Goddess. Yet, despite the fact that authorities acknowledge that the preeminent deity of Crete was a Female Divine, and that women played a major role in Cretan society, there is a gap in the scholarly literature, and a lively, ongoing debate regarding the centrality of women and the existence of matriarchy in Bronze Age Crete.The purpose of this work is to fill that gap, and to advance the debate over whether or not ancient Crete was a woman-centered and matriarchal society toward a more complex, detailed, and certain conclusion. To that end this publication utilises the field of modern matriarchal studies, with its carefully elucidated definition of the term matriarchy, and employs the methodology of archaeomythology – the use of historical, mythological, linguistic, and folkloric as well as archaeological sources.Given its scope, the volume will be of interest to scholars and students in the fields encompassed by archaeomythology, as well as the fields of women’s studies, women’s history, women’s spirituality, and modern matriarchal studies

Matriarchy in Bronze Age Crete

"Matriarchy in Bronze Age Crete: A Perspective from Archaeomythology and Modern Matriarchal Studies offers a very different perspective of Crete than is usually found in academic writing; making a compelling case for a matriarchal Bronze Age Crete. Bronze Age Crete evokes for many the image of an exceptionally sophisticated civilization: peaceful, artistic, and refined; a society in which women were highly visible and important, and the supreme deity was a Goddess. Yet, despite the fact that authorities acknowledge that the preeminent deity of Crete was a Female Divine, and that women played a major role in Cretan society, there is a gap in the scholarly literature, and a lively, ongoing debate regarding the centrality of women and the existence of matriarchy in Bronze Age Crete. The purpose of this work is to fill that gap, and to advance the debate over whether or not ancient Crete was a woman-centered and matriarchal society toward a more complex, detailed, and certain conclusion. To that end this publication utilises the field of modern matriarchal studies, with its carefully elucidated definition of the term matriarchy, and employs the methodology of archaeomythology – the use of historical, mythological, linguistic, and folkloric as well as archaeological sources. Given its scope, the volume will be of interest to scholars and students in the fields encompassed by archaeomythology, as well as the fields of women’s studies, women’s history, women’s spirituality, and modern matriarchal studies.