Doped silicon and NIS junctions for bolometer applications

We discuss the performance, of a normal metal hot electron bolometer (NHEB) that we have measured at 0.3 K. We found that the noise equivalent power was limited by the amplifier noise. To improve the NHEB power response and to make it more robust and reliable we propose to substitute the normal metal with heavily doped silicon. The heavily doped silicon behaves like a metal with lower carrier concentration and has a smaller electron–phonon thermal coupling. We have fabricated superconductor-doped silicon-superconductor contacts (S-Sm-S) and we have used them as thermometers and coolers.     

A Novel Particle/Photon Detector Based on a Superconducting Proximity Array of Nanodots

The current frontiers in the investigation of high-energy particles demand for new detection methods. Higher sensitivity to low-energy deposition, high-energy resolution to identify events and improve the background rejection, and large detector masses have to be developed to detect even an individual particle that weakly interacts with ordinary matter. Here, we will describe the concept and the layout of a novel superconducting proximity array which show dynamic vortex Mott insulator to metal transitions, as an ultra-sensitive compact radiation-particle detector.     

A Pharmacogenetics Study in Mozambican Patients Treated with Nevirapine: Full Resequencing of TRAF3IP2 Gene Shows a Novel Association with SJS/TEN Susceptibility

Steven–Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are severe adverse drug reactions, characterized by extensive epidermal detachment and erosions of mucous membrane. SJS/TEN is one of the most serious adverse reactions to Nevirapine (NVP) treatment, commonly used in developing countries as first-line treatment of human immunodeficiency virus infection. In the last years TRAF3IP2 gene variants had been described as associated with susceptibility to several diseases such as psoriasis and psoriatic arthritis. We hypothesized that this gene, involved in immune response and in NF-κB activation, could also be implicated in the SJS/TEN susceptibility. We performed a full resequencing of TRAF3IP2 gene in a population of patients treated with NVP. Twenty-seven patients with NVP-induced SJS/TEN and 78 controls, all from Mozambique, were enrolled. We identified eight exonic and three intronic already described variants. The case/control association analysis highlighted an association between the rs76228616 SNP in exon 2 and the SJS/TEN susceptibility. In particular, the variant allele (C) resulted significantly associated with a higher risk to develop SJS/TEN (p = 0.012 and OR = 3.65 (95% CI 1.33–10.01)). A multivariate analysis by logistic regression confirmed its significant contribution (p = 0.027, OR = 4.39 (95% CI 1.19–16.23)). In conclusion, our study suggests that a variant in TRAF3IP2 gene could be involved in susceptibility to SJS/TEN.     

A versatile framework for a narrow- and wide-band statisticalpropagation model for the LMS channel

In this paper a framework for the development of a versatile statistical land mobile satellite (LMS) channel model, both narrow- and wide-band, is presented. First, a review is made of the different model elements that can be described statistically. Another specification set for the development of a comprehensive statistical model is that some physical/geometrical information should be included in spite of its fully statistical nature. The model shall be valid for applications such as communications, broadcast, navigation, etc., also it must consider different orbit types, and frequency bands. This paper summarises some of the activities to be carried out under ESA (European Space Agency) Contract No 12409/97/NL/NB for the development of a “Statistical Model for the LMS Channel”     

Numerical Analysis on a Latent Thermal Energy Storage System with Phase Change Materials and Aluminum Foam

Abstract

A latent heat thermal energy storage system with phase change material (PCM) is numerically studied. To enhance the heat transfer inside the system, a highly conductive metal foam is employed with ceramic nanoparticles. The latter method of enhancement leads to a new class of material called Nano-PCM. The system under investigation is a 70-L tank filled up with pure PCM or Nano-PCM and several pipes are situated where the heat transfer fluid (HTF) flows. The pipe surfaces are assumed at constant temperature above the PCM melting temperature to simulate the heat transfer from the HTF. The enthalpy-porosity theory is applied to simulate the PCM phase change, while the porous media formulation is assumed to describe the metal foam behavior. The nano-PCM is modeled with single-phase model where the properties are the weighted-average between the fluid base and the nanoparticles. The simulations are accomplished for charging-discharging process at different porosities and nanoparticle concentration. The results are given in term of average melting fraction evolution, average temperature as function of time, average stored energy. The metal foam significantly improves the heat transfer between PCM and HTF respect to the addition of nanoparticles, reducing the charging and discharging time more than one order of magnitude.     

A collocation algorithm for calculating the periodic solutions of non-linear oscillators

An approximation method is given for calculating the periodic solutions of non-linear oscillators based upon the well-known method of collocation, which belongs to the class of projection methods. Unlike available techniques, the method leads to a simple and efficient algorithmic procedure which consists of solving a system of non-linear equations given in a simple explicit form. To demonstrate the effectiveness of the proposed algorithm, the results of some typical oscillator circuits are provided.     

Adiponectin and Leptin Exert Antagonizing Effects on HUVEC Tube Formation and Migration Modulating the Expression of CXCL1, VEGF,MMP-2 and MMP-9

Adiponectin and leptin are two abundant adipokines with different properties but both described such as potent factors regulating angiogenesis. AdipoRon is a small-molecule that, binding to AdipoRs receptors, acts as an adiponectin agonist. Here, we investigated the effects of AdipoRon and leptin on viability, migration and tube formation on a human in vitro model, the human umbilical vein endothelial cells (HUVEC) focusing on the expression of the main endothelial angiogenic factors: hypoxia-inducible factor 1-alpha (HIF-1α), C-X-C motif chemokine ligand 1 (CXCL1), vascular endothelial growth factor A (VEGF-A), matrix metallopeptidase 2 (MMP-2) and matrix metallopeptidase 9 (MMP-9). Treatments with VEGF-A were used as positive control. Our data revealed that, at 24 h treatment, proliferation of HUVEC endothelial cells was not influenced by AdipoRon or leptin administration; after 48 h longer exposure time, the viability was negatively influenced by AdipoRon while leptin treatment and the combination of AdipoRon+leptin produced no effects. In addition, AdipoRon induced a significant increase in complete tubular structures together with induction of cell migration while, on the contrary, leptin did not induce tube formation and inhibited cell migration; interestingly, the co-treatment with both AdipoRon and leptin determined a significant decrease of the tubular structures and cell migration indicating that leptin antagonizes AdipoRon effects. Finally, we found that the effects induced by AdipoRon administration are accompanied by an increase in the expression of CXCL1, VEGF-A, MMP-2 and MMP-9. In conclusion, our data sustain the active role of adiponectin and leptin in linking adipose tissue with the vascular endothelium encouraging the further deepening of the role of adipokines in new vessel’s formation, to candidate them as therapeutic targets.     

Telomere Length and Male Fertility

Over the past decade, telomeres have attracted increasing attention due to the role they play in human fertility. However, conflicting results have been reported on the possible association between sperm telomere length (STL) and leukocyte telomere length (LTL) and the quality of the sperm parameters. The aim of this study was to run a comprehensive study to investigate the role of STL and LTL in male spermatogenesis and infertility. Moreover, the association between the sperm parameters and 11 candidate single nucleotide polymorphisms (SNPs), identified in the literature for their association with telomere length (TL), was investigated. We observed no associations between sperm parameters and STL nor LTL. For the individual SNPs, we observed five statistically significant associations with sperm parameters: considering a p < 0.05. Namely, ACYP2˗rs11125529 and decreased sperm motility (p = 0.03); PXK˗rs6772228 with a lower sperm count (p = 0.02); NAF1˗rs7675998 with increased probability of having abnormal acrosomes (p = 0.03) and abnormal flagellum (p = 0.04); ZNF208˗rs8105767 and reduction of sperms with normal heads (p = 0.009). This study suggests a moderate involvement of telomere length in male fertility; however, in our analyses four SNPs were weakly associated with sperm variables, suggesting the SNPs to be pleiotropic and involved in other regulatory mechanisms independent of telomere homeostasis, but involved in the spermatogenic process.     

Robust state of charge and state of health estimation for batteries using a novel multi model approach

Estimation of state-of-charge and state-of-health for batteries is one of the most important feature for modern battery management system (BMS). Robust or adaptive methods are the most investigated because a more intelligent BMS could lead to sensible cost reduction of the entire battery system. We propose a new robust method, called ERMES (extendible range multi-model estimator), for determining an estimated state-of-charge (SoC), an estimated state-of-health (SoH) and a prediction of uncertainty of the estimates (state-of-uncertainty—SoU), thanks to which it is possible to monitor the validity of the estimates and adjust it, extending the robustness against a wider range of uncertainty, if necessary. Specifically, a finite number of models in state-space form are considered starting from a modified Thevenin battery model. Each model is characterized by a hypothesis of SoH value. An iterated extended Kalman filter (EKF) is then applied to each model in parallel, estimating for each one the SoC state variable. Residual errors are then considered to fuse both the estimated SoC and SoH from the bank of EKF, yielding the overall SoC and SoH estimates, respectively. In addition, a figure of uncertainty of such estimates is also provided.     

Atypical presentation of Clostridium difficile colitis in patients with cystic fibrosis

OBJECTIVE: This report describes the unusual presentation of Clostridium difficile colitis in five patients with cystic fibrosis and the role of CT in first suggesting the correct diagnosis in this group of patients. Because of the absence of watery diarrhea and the presence of abdominal bloating and decreased stooling, cystic fibrosis patients with C. difficile colitis will be treated for stool impaction, meconium ileus equivalent, or distal intestinal obstruction syndrome. CT of the abdomen, performed in these five patients because of their lack of improvement after standard therapy for stool impaction, showed an extensive pancolitis later confirmed to be caused by C. difficile infection. CONCLUSION: In patients with cystic fibrosis, imaging findings of a pancolitis should raise the possibility of C. difficile colitis despite the lack of watery diarrhea. Anticlostridial treatment can be initiated before bacteriologic confirmation is obtained.