HELNED: Helium-3-free low-cost neutron detectors

We developed a technique for thermal neutron detection not making use of 3He, also suitable for online real time monitoring of CASTOR spent fuel containers. As a neutron converter we used 6LiF, being the neutron capture cross section of 6Li very well known and with only an alpha and a triton in the exit channel. We can deposit thin layers of converter onto several different substrates, to be placed on top of solid state detectors or scintillators capable of efficiently detecting the decay products

Erectile Dysfunction in Diabetic Patients: From Etiology to Management

Diabetes mellitus (DM) is a widespread chronic disease with a prevalence that is expected to further increase in the near future. The classical management of DM includes the normalization of the glycometabolic profile and the evaluation of cardiac and cerebral vascular health by the intervention of an array of different specialists. However, so far, sexual dysfunctions are still a neglected complication in patients with DM, although there is an elevated prevalence of this long-term complication in male and female patients. Furthermore, some of them may represent a sign of vascular alteration and/or hypogonadism and require timely management to prevent the onset of major adverse cardiac events. This narrative review briefly summarizes the current evidence on epidemiology, pathogenesis, diagnosis, and therapy of erectile dysfunction in male patients with DM to support diabetologists in clinical practice

Surgical management of Glioma Grade 4: technical update from the neuro-oncology section of the Italian Society of Neurosurgery (SINch®): a systematic review

Purpose: The extent of resection (EOR) is an independent prognostic factor for overall survival (OS) in adult patients with Glioma Grade 4 (GG4). The aim of the neuro-oncology section of the Italian Society of Neurosurgery (SINch®) was to provide a general overview of the current trends and technical tools to reach this goal. Methods: A systematic review was performed. The results were divided and ordered, by an expert team of surgeons, to assess the Class of Evidence (CE) and Strength of Recommendation (SR) of perioperative drugs management, imaging, surgery, intraoperative imaging, estimation of EOR, surgery at tumor progression and surgery in elderly patients. Results: A total of 352 studies were identified, including 299 retrospective studies and 53 reviews/meta-analysis. The use of Dexamethasone and the avoidance of prophylaxis with anti-seizure medications reached a CE I and SR A. A preoperative imaging standard protocol was defined with CE II and SR B and usefulness of an early postoperative MRI, with CE II and SR B. The EOR was defined the strongest independent risk factor for both OS and tumor recurrence with CE II and SR B. For intraoperative imaging only the use of 5-ALA reached a CE II and SR B. The estimation of EOR was established to be fundamental in planning postoperative adjuvant treatments with CE II and SR B and the stereotactic image-guided brain biopsy to be the procedure of choice when an extensive surgical resection is not feasible (CE II and SR B). Conclusions: A growing number of evidences evidence support the role of maximal safe resection as primary OS predictor in GG4 patients. The ongoing development of intraoperative techniques for a precise real-time identification of peritumoral functional pathways enables surgeons to maximize EOR minimizing the post-operative morbidity

National trends in total cholesterol obscure heterogeneous changes in HDL and non-HDL cholesterol and total-to-HDL cholesterol ratio : a pooled analysis of 458 population-based studies in Asian and Western countries

Background: Although high-density lipoprotein (HDL) and non-HDL cholesterol have opposite associations with coronary heart disease, multi-country reports of lipid trends only use total cholesterol (TC). Our aim was to compare trends in total, HDL and nonHDL cholesterol and the total-to-HDL cholesterol ratio in Asian and Western countries. Methods: We pooled 458 population-based studies with 82.1 million participants in 23 Asian and Western countries. We estimated changes in mean total, HDL and non-HDL cholesterol and mean total-to-HDL cholesterol ratio by country, sex and age group. Results: Since similar to 1980, mean TC increased in Asian countries. In Japan and South Korea, the TC rise was due to rising HDL cholesterol, which increased by up to 0.17 mmol/L per decade in Japanese women; in China, it was due to rising non-HDL cholesterol. TC declined in Western countries, except in Polish men. The decline was largest in Finland and Norway, at similar to 0.4 mmol/L per decade. The decline in TC in most Western countries was the net effect of an increase in HDL cholesterol and a decline in non-HDL cholesterol, with the HDL cholesterol increase largest in New Zealand and Switzerland. Mean total-to-HDL cholesterol ratio declined in Japan, South Korea and most Western countries, by as much as similar to 0.7 per decade in Swiss men (equivalent to similar to 26% decline in coronary heart disease risk per decade). The ratio increased in China. Conclusions: HDL cholesterol has risen and the total-to-HDL cholesterol ratio has declined in many Western countries, Japan and South Korea, with only a weak correlation with changes in TC or non-HDL cholesterol.Peer reviewe

Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018 population-based measurement studies with 88.6 million participants

© The Author(s) 2018. Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups

Quench Protection Heaters FE Analysis and Thermal Conductivity Measurements of Nb3Sn Cables for High-Field Accelerator Magnets

The Large Hadron Collider (LHC), the world’s largest and most powerful particle accelerator, represents a research instrument at CERN to improve our understanding of matter and the Universe. To date, scientists and engineers around the world are working hard to develop its upgrade, the High-Luminosity LHC (HL-LHC). More powerful superconducting accelerator magnets are being designed at CERN, allowing the peak magnetic field strength to be augmented by around 50% than current LHC magnets. These magnets will permit to increase the HL-LHC integrated luminosity - i.e. the total number of collisions – by a factor of ten beyond the LHC’s design value, allowing the scientific community to study the phenomena discovered at the LHC in greater detail. Due to the high peak field, in the range of 12 T to 13 T, magnets will use an innovative superconducting technology based on the use of Nb3Sn as a superconductor. From this perspective, quench protection is becoming a topic of very high interest. That means preventing damage in the case of an unexpected loss of superconductivity and the heat generation related to that. This procedure foresees the disconnection of the magnet current supply and the use of so-called quench heaters. The heaters suppress the superconducting state in a large fraction of the windings and permit a uniform dissipation of the stored energy. In this thesis work, a numerical analysis on state-of-the-art quench protection heaters for high-field accelerators magnets is proposed, aiming to investigate on their performance and evaluate the prospects in high-field magnet protection. FE-analyses simulating the heat transfer from protection heater to superconducting cables in Nb3Sn magnets were carried-out in COMSOL Multiphysics®, in order to evaluate the heater efficiency from the time delay between the heater activation and normal zone initiation in the coil. Results from simulations were compared with measured data from R&D Nb3Sn quadrupoles and dipoles under development at CERN for the HiLumi project. The thesis was also focused on the study of the thermal conductivity of epoxy-impregnated coils, for having a better understanding of this thermal property which plays a key role in heat transfer phenomena during a quench. The thermal conductivity of different insulating materials used in Nb3Sn impregnated coils was studied. Finally, a multi-strand cables FE-model was built in COMSOL to replicate the experimental procedure used at CERN Cryolab to measure the thermal conductivity of epoxy-impregnated Nb3Sn Rutherford cable stacks

On the Lifetime Estimation of SiC Power MOSFETs for Motor Drive Applications

This work presents a step-by-step procedure to estimate the lifetime of discrete SiC power MOSFETs equipping three-phase inverters of electric drives. The stress of each power device when it is subjected to thermal jumps from a few degrees up to about 80 °C was analyzed, starting from the computation of the average power losses and the commitment of the electric drive. A customizable mission profile was considered where, by accounting the working conditions of the drive, the corresponding average power losses and junction temperatures of the SiC MOSFETs composing the inverter can be computed. The tool exploits the Coffin–Manson theory, rainflow counting, and Miner’s rule for the lifetime estimation of the semiconductor power devices. Different operating scenarios were investigated, underlying their impact on the lifetime of SiC MOSFETs devices. The lifetime estimation procedure was realized with the main goal of keeping limited computational efforts, while providing an effective evaluation of the thermal effects. The method enables us to set up any generic mission profile from the electric drive model. This gives us the possibility to compare several operating scenario of the drive and predict the worse operating conditions for power devices. Finally, although the lifetime estimation tool was applied to SiC power MOSFET devices for a general-purpose application, it can be extended to any type of power switch technology

On the Lifetime Estimation of SiC Power MOSFETs for Motor Drive Applications

This work presents a step-by-step procedure to estimate the lifetime of discrete SiC power MOSFETs equipping three-phase inverters of electric drives. The stress of each power device when it is subjected to thermal jumps from a few degrees up to about 80 °C was analyzed, starting from the computation of the average power losses and the commitment of the electric drive. A customizable mission profile was considered where, by accounting the working conditions of the drive, the corresponding average power losses and junction temperatures of the SiC MOSFETs composing the inverter can be computed. The tool exploits the Coffin–Manson theory, rainflow counting, and Miner’s rule for the lifetime estimation of the semiconductor power devices. Different operating scenarios were investigated, underlying their impact on the lifetime of SiC MOSFETs devices. The lifetime estimation procedure was realized with the main goal of keeping limited computational efforts, while providing an effective evaluation of the thermal effects. The method enables us to set up any generic mission profile from the electric drive model. This gives us the possibility to compare several operating scenario of the drive and predict the worse operating conditions for power devices. Finally, although the lifetime estimation tool was applied to SiC power MOSFET devices for a general-purpose application, it can be extended to any type of power switch technology

Does Sperm <i>SNRPN</i> Methylation Change with Fertility Status and Age? A Systematic Review and Meta-Regression Analysis

Background: The Small Nuclear Ribonucleoprotein Polypeptide N (SNRPN) gene is a paternally expressed imprinted gene, whose abnormal methylation appears to be associated with syndromes associated with the use of assisted reproductive techniques (ART), such as Angelman and Prader–Willi. Data present in the literature suggest the association between aberrant sperm SNRPN gene methylation and abnormal sperm parameters. The latest meta-analysis on the methylation pattern of this gene in spermatozoa of infertile patients published in 2017 reported a higher degree of methylation in the spermatozoa of infertile patients compared to fertile controls. Objectives: Here we provide an updated and comprehensive systematic review and meta-analysis of the sperm methylation pattern of the SNRPN gene in patients with abnormal sperm parameters/infertility compared to men with normal sperm parameters/fertile. For the first time in the literature, we performed a meta-regression analysis to evaluate whether age or sperm concentration could influence the methylation status of this gene at the sperm level. Methods: This meta-analysis was registered in PROSPERO (n. CRD42023397056). The Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) and the MOOSE guidelines for meta-analyses and systematic reviews of observational studies were strictly followed in our meta-analysis. According to our Population Exposure Comparison Outcome (PECO) question, we included data from original articles assessing the levels of SNRPN gene methylation at the sperm level in infertile patients or patients with abnormalities in one or more sperm parameters compared to fertile or normozoospermic men. Results: Only six of 354 screened studies were included in the quantitative synthesis. Our analysis showed significantly higher levels of SNRPN gene methylation in patients compared to controls. However, significant heterogeneity was found between studies. In sensitivity analysis, no studies were sensitive enough to skew the results. The Egger test showed no publication bias. In the meta-regression analysis, the results were independent of age and sperm concentration in the overall population. The same results were found in the control group. However, when analyzing the patient group, a direct correlation was found between SNRPN methylation and age, indicating that the degree of methylation of the SNRPN gene increases with advancing age. Conclusions: Fertility status or abnormality of sperm parameters is associated with a change in the methylation pattern of the SNRPN gene, with higher levels found in infertile patients or those with abnormal sperm parameters compared to fertile men or men with normal sperm parameters. In the group of infertile patients/patients with abnormal sperm parameters, age was directly correlated to the degree of SNRPN methylation, highlighting the presence of a mechanism that explains the age-related altered sperm quality and the risk of ART. Despite some limitations present in the analyzed studies, our results support the inclusion of SNRPN methylation in the genetic panel of prospective studies aimed at identifying the most representative and cost-effective genes to analyze in couples who want to undergo ART