Pulse-tube dilution refrigeration below 10 mK for Astrophysics

International audienceAstroparticle bolometric detectors often rely on the use of dilution refrigerators providing a large cooling power at millikelvin temperatures. Conventional machines, however, need a systematic supply of cryogenic fluids, complicating and making more expensive their operation, particularly in underground laboratories. We describe here novel cryogen-free dilution units, able to cool down large detectors to millikelvin temperatures, and where cooling and warming times have been optimised

Experimental results on the free cooling power available on 4K pulse tube coolers

International audienceWe report experimental results on the free cooling power available at the level of the second stage regenerator of a 4K pulse tube cooler. By using two localised heat exchangers we obtained additional cooling power, in the range 400 and 600mW at 4.8K or between 500 and 700mW at 18K. We have investigated in detail the thermal behavior of the system. In this manuscript we report on the evolution of the temperature of the heat exchangers and the pulse tube stages under different distributions of the total heat load

Pulse-tube dilution refrigeration below 10 mK

International audienceWe report the design, realization and performance of dilution refrigerators using a pulse-tube cooler as a first cryogenic stage. The absence of a Dewar containing cryogenic fluids makes this new type of refrigerators particularly versatile. The system provides relatively high cooling power, and reaches temperatures well below 10 mK

Depth of Formation of Ferropericlase Included in Super-Deep Diamonds

Super-deep diamonds are believed to have formed at depths of at least 300 km depth (Harte, 2010). A common mineral inclusion in these diamonds is ferropericlase, (Mg,Fe)O (see Kaminsky, 2012 and references therein). Ferropericlase (fPer) is the second most abundant mineral in the lower mantle, comprising approximately 16\u201320 wt% (660 to 2900 km depth), and inclusions of fPer in diamond are often considered to indicate a lower-mantle origin (Harte et al., 1999). Samples from S\ue3o Luiz/Juina, Brazil, are noteworthy for containing nanometer-sized magnesioferrite (Harte et al., 1999; Wirth et al., 2014; Kaminsky et al., 2015; Palot et al., 2016). Based upon a phase diagram valid for 1 atm, such exsolutions would place the origin of this assemblage in the uppermost part of the lower mantle. However, a newly reported phase diagram for magnesioferrite demonstrates that the latter is not stable at such pressures and, thus, it cannot exsolve directly from fPer at lower-mantle conditions (Uenver-Thiele et al., 2017). Here we report the investigation of two fPer inclusions, extracted from a single S\ue3o Luiz diamond, by single-crystal X-ray diffraction and field emission scanning electron microscopy. Both techniques showed micrometer-sized exsolutions of magnesioferrite within the two fPers. We also completed elastic geobarometry (see Angel et al., 2015), which determined an estimate for the depth of entrapment of the two ferropericlase \u2013 diamond pairs. In the temperature range between 1273 and 1773 K, pressures varied between 9.88 and 12.34 GPa (325-410 km depth) for one inclusion and between 10.69 and 13.16 GPa (350-440 km depth) for the other one. These results strengthen the hypothesis that solitary fPer inclusions might not be reliable markers for a lower-mantle provenance

Depth of diamond formation obtained from single periclase inclusions

Super-deep diamonds (SDDs) are those that form at depths between ~300 and ~1000 km in Earth's mantle. They compose only 1% of the entire diamond population but play a pivotal role in geology, as they represent the deepest direct samples from the interior of our planet. Ferropericlase, (Mg,Fe)O, is the most abundant mineral found as inclusions in SDDs and, when associated with low-Ni enstatite, which is interpreted as retrogressed bridgmanite, is considered proof of a lower-mantle origin. As this mineral association in diamond is very rare, the depth of formation of most ferropericlase inclusions remains uncertain. Here we report geobarometric estimates based on both elasticity and elastoplasticity theories for two ferropericlase inclusions, not associated with enstatite, from a single Brazilian diamond. We obtained a minimum depth of entrapment of 15.7 (±2.5) GPa at 1830 (±45) K (~450 [±70] km depth), placing the origin of the diamond-inclusion pairs at least near the upper mantle-transition zone boundary and confirming their super-deep origin. Our analytical approach can be applied to any type of mineral inclusion in diamond and is expected to allow better insights into the depth distribution and origin of SDDs

Subcutaneous immunoglobulins replacement therapy in secondary antibody deficiencies: real life evidence as compared to primary antibody deficiencies

Secondary antibody deficiencies (SAD) may require immunoglobulin replacement therapy (IgRT). While the intravenous route (IVIG) is broadly considered effective in SAD, the use of subcutaneous immunoglobulins (SCIG) is mainly adopted from the experience in primary antibody deficiencies (PAD), where SCIG have been shown to perform as effective as IVIG. However, evidence-based data on SCIG administration in SAD patients are still insufficient. Herein we retrospectively evaluated the efficacy and safety profile of SCIG treatment in 131 SAD patients as compared to a group of 102 PAD patients. We found SCIG being equally effective in reducing annual infectious rate both in SAD and PAD patients. However, SAD patients required lower SCIG dosage and lower IgG through level to achieve similar biological effect in terms of infection burden, at the steady state. SAD patients also showed better correlation between SCIG dose and serum IgG achieved value. Furthermore, within SAD, SCIG were found to work irrespective of the underlying disease. Especially in Non-Hodgkin Lymphoma patients, whose indication to IgRT is still not included in all guidelines and for whom evidence-based data are still lacking, SCIG were as effective as in Chronic Lymphocytic Leukemia or Multiple Myeloma patients, and SCIG discontinuation, without evidence of B cell recovery, led to IgG decline and relapsed infections. Finally, treatment tolerance in SAD patients was comparable to the PAD cohort. Globally, our data suggest that SCIG, as already appreciated in PAD, represent a valuable option in SAD patients, independent on the disease leading to antibody deficiency

Common and uncommon CT findings in CVID-related GL-ILD: correlations with clinical parameters, therapeutic decisions and potential implications in the differential diagnosis

Purpose: To investigate computed tomography (CT) findings of Granulomatous Lymphocytic Interstitial Lung Disease (GL-ILD) in Common Variable Immunodeficiency (CVID), also in comparison with non-GL-ILD abnormalities, correlating GL-ILD features with functional/immunological parameters and looking for GL-ILD therapy predictive elements. Methods: CT features of 38 GL-ILD and 38 matched non-GL-ILD subjects were retrospectively described. Correlations of GL-ILD features with functional/immunological features were assessed. A logistic regression was performed to find a predictive model of GL-ILD therapeutic decisions. Results: Most common GL-ILD CT findings were bronchiectasis, non-perilymphatic nodules, consolidations, Ground Glass Opacities (GGO), bands and enlarged lymphnodes. GL-ILD was usually predominant in lower fields. Multiple small nodules (≤10 mm), consolidations, reticulations and fibrotic ILD are more indicative of GL-ILD. Bronchiectasis, GGO, Reticulations and fibrotic ILD correlated with decreased lung performance. Bronchiectasis, GGO and fibrotic ILD were associated with low IgA levels, whereas high CD4+ T cells percentage was related to GGO. Twenty out of 38 patients underwent GL-ILD therapy. A model combining Marginal Zone (MZ) B cells percentage, IgA levels, lower field consolidations and lymphnodes enlargement showed a good discriminatory capacity with regards to GL-ILD treatment. Conclusions: GL-ILD is a lower field predominant disease, commonly characterized by bronchiectasis, non-perilymphatic small nodules, consolidations, GGO and bands. Multiple small nodules, consolidations, reticulations and fibrotic ILD may suggest the presence of GL-ILD in CVID. MZ B cells percentage, IgA levels at diagnosis, lower field consolidations and mediastinal lymphnodes enlargement may predict the need of a specific GL-ILD therapy

Saúde Ambiental e Atenção Primária à Saúde nos microterritórios: a taxa de mortalidade infantil para subsidiar a atuação da equipe de saúde

In the past 20 years, the Brazilian Unified Health System has improved primary health care and the implementation of environmental health surveillance. In Brazil, basic sanitation coverage has also improved. Macro-regional inequalities are known to exist, but there is little information about the micro-territories where primary care actions are being carried out. This study attempts to describe the influence of drinking water coverage (DWC), sanitation (SC) and solid waste management services (SWMS) on the infant mortality rate (IMR) in areas covered by primary care facilities (PCF), within the Northwest Health District of Campinas/SP. An ecological study was conducted using secondary data for the year 2000. In the eight PCF, DWC varied between 96.3 % and 99.9 %, SC between 67 % and 99.8 %, and SWMS between 95.8 % and 99.9 %. The IMR varied between 5.5 ‰ and 22.9 ‰. An inverse relationship was found, in which the larger the DWC (R2= 0.73), SC (R2= 0.78) and SWMS (R2= 0.95) the lower was the IMR. In addition to other factors, basic sanitation affects the health of the population and, according to the results presented here, there are inequalities in the areas covered by the PCF. Therefore, managers and health professionals, especially those in primary care, should take these factors into consideration to set priorities, actions and targets for integral care, intersectoral collaboration and health surveillance.En los últimos 20 años, el Sistema Único de Salud en el Brasil ha mejorado la atención primaria de salud y la vigilancia de la salud ambiental. En Brasil, mejoró también la cobertura de saneamiento básico. Existen desigualdades macrorregionales y poca información sobre los microterritorios donde se llevan a cabo las acciones de la atención primaria. Se pretende describir la influencia de la cobertura de agua potable (CAP), servicios de saneamiento (SS) y servicios de gestión de los residuos sólidos municipales (RSM) en la tasa mortalidad infantil (TMI) de las zonas cubiertas por las unidades básicas de salud (UBS) del Distrito de Salud Noroeste de Campinas-SP. Se trata de un estudio ecológico realizado con datos secundarios para el año 2000. En las ocho UBS la CAP osciló entre 96,3 % y 99,9 %; los SS entre 67 % y 99,8 %; los servicios de gestión de RSM entre 95,8 % y 99,9 %. La TMI osciló en las diferentes UBS entre 5,5 ‰ y 22,9 ‰. Se observó que existe una relación inversa, cuanto mayor es la CAP (R2= 0,73), los SS (R2= 0,78) y los servicios de gestión de RSM (R2= 0,95) menor es la TMI. Además de otros factores, el saneamiento básico interfiere en la salud de la población y de acuerdo con los resultados presentados, también existen desigualdades en las áreas cubiertas por las UBS. Estas deben ser consideradas por los directivos y profesionales de la salud, especialmente de la atención primaria, para establecer las prioridades, acciones y metas para la atención integral y vigilancia de la salud y el trabajo intersectorial.Nos últimos 20 anos, o Sistema Único de Saúde no Brasil vem avançando no aprimoramento da atenção primaria e da vigilância em saúde ambiental. No País, também, melhorou a cobertura do saneamento básico. Mas existem iniquidades macrorregionais e são escassas as informações sobre os microterritórios, onde as ações básicas de saúde se concretizam. Descrever a influência das coberturas do sistema de abastecimento de água (SAA), esgotamento sanitário (ES) e coleta de resíduos sólidos domiciliares (CRSD) na taxa mortalidade infantil (TMI) nas áreas de abrangência das unidades básicas de saúde (UBS) do Distrito de Saúde Noroeste de Campinas-SP. Foi conduzido estudo ecológico com dados secundários referentes a 2000. As coberturas nas oito UBS: do SAA variou entre 96,3 %, de Valença, e 99,9 % de Integração; de ES entre 67 %, de Ipaussurama e 99,8 % de Integração; da CRSD entre 95,8 % de Florence e 99,9 % de Perseu e Integração. A TMI variou entre 5,5 ‰, na UBS Perseu e 22,9 ‰ Floresta. Observou-se que existe relação inversa, quanto maior a cobertura do SAA (R2=0,73), de ES (R2=0,78) e da CRSD (R2= 0,95) menor a TMI nas UBS. Além de outros fatores, o saneamento básico determina o processo saúde doença da população e conforme os achados, existem iniquidades também nos microterritórios de abrangência das UBS que devem ser consideradas pelos gestores e profissionais de saúde, principalmente, da atenção primária na pactuação das prioridades, ações e metas para atenção integral e vigilância em saúde e atuação intersetorial

Granulomatous Lymphocytic Interstitial Lung Disease (GLILD) in Common Variable Immunodeficiency (CVID): A Multicenter Retrospective Study of Patients From Italian PID Referral Centers

Background: Granulomatous and Lymphocytic Interstitial Lung Diseases (GLILD) is a severe non-infectious complication of Common Variable Immunodeficiency (CVID), often associated with extrapulmonary involvement. Due to a poorly understood pathogenesis, GLILD diagnosis and management criteria still lack consensus. Accordingly, it is a relevant cause of long-term loss of respiratory function and is closely associated with a markedly reduced survival. The aim of this study was to describe clinical, immunological, laboratory and functional features of GLILD, whose combination in a predictive model might allow a timely diagnosis. Methods: In a multicenter retrospective cross-sectional study we enrolled 73 CVID patients with radiologic features of interstitial lung disease (ILD) associated to CVID (CVID-ILD) and 125 CVID patients without ILD (controls). Of the 73 CVID-ILD patients, 47 received a definite GLILD diagnosis while 26 received a clinical-radiologic diagnosis of CVID related ILD defined as uILD. Results: In GLILD group we found a higher prevalence of splenomegaly (84.8 vs. 39.2%), autoimmune cytopenia (59.6 vs. 6.4%) and bronchiectasis (72.3 vs. 28%), and lower IgA and IgG serum levels at CVID diagnosis. GLILD patients presented lower percentage of switched-memory B cells and marginal zone B cells, and a marked increase in the percentage of circulating CD21lo B cells (14.2 vs. 2.9%). GLILD patients also showed lower total lung capacity (TLC 87.5 vs. 5.0%) and gas transfer (DLCO 61.5 vs. 5.0%) percent of predicted. By univariate logistic regression analysis, we found IgG and IgA levels at CVID diagnosis, presence of splenomegaly and autoimmune cytopenia, CD21lo B cells percentage, TLC and DCLO percent of predicted to be associated to GLILD. The joint analysis of four variables (CD21lo B cells percentage, autoimmune cytopenia, splenomegaly and DLCO percent of predicted), together in a multiple logistic regression model, yielded an area under the ROC curve (AUC) of 0.98 (95% CI: 0.95-1.0). The AUC was only slightly modified when pooling together GLILD and uILD patients (0.92, 95% CI: 0.87-0.97). Conclusions: we propose the combination of two clinical parameters (splenomegaly and autoimmune cytopenia), one lung function index (DLCO%) and one immunologic variable (CD21lo%) as a promising tool for early identification of CVID patients with interstitial lung disease, limiting the use of aggressive diagnostic procedures