Development of an OpenFOAM multiphysics solver for solid fission products transport in the Molten Salt Fast Reactor

The analysis of innovative reactor concepts such as the Molten Salt Fast Reactor (MSFR) requires the development of new modeling and simulation tools. In the case of the MSFR, the strong intrinsic coupling between thermal-hydraulics, neutronics and fuel chemistry has led to the adoption of the multiphysics approach as a state-of-the-art paradigm. One of the peculiar aspects of liquid-fuel reactors such as the MSFR is the mobility of fission products (FPs) in the reactor circuit. Some FP species appear in form of solid precipitates carried by the fuel flow and can deposit on reactor boundaries (e.g., heat exchangers), potentially representing design issues related to the degradation of heat exchange performance or radioactive hotspots. The integration of transport models for solid particles in multiphysics codes is therefore relevant for the prediction of deposited fractions. To this aim, we develop a multiphysics solver based on the OpenFOAM library to address the issue of solid fission products transport. Single-phase incompressible thermal hydraulics are coupled with neutron diffusion, and advection-diffusion-decay equations are implemented for fission products concentrations. Particle deposition and precipitation are considered as well. The developed solver is tested on two different MSFR application to showcase the capabilities of the solver in steady-state simulation and to investigate the role of precipitation and turbulence modeling in the determination of particle concentration distributions

Ivabradine, heart failure and chronic kidney disease

The incidence and prevalence of congestive heart failure are actually increasing worldwide, especially inWestern countries. In Europe and the United States, congestive heart failure represents a disabling clinical disease, accountable for increased hospitalization and health care costs. European guidelines have underlined the importance of pharmacological treatment to improve both patients\u2019 outcomes and quality of life. The latest clinical trials to evaluate ivabradine\u2019s efficacy have underlined its usefulness as a stand-alone medication and in combination with conventional congestive heart failure therapy, including in chronic kidney disease patients

Representing environmental harm and resistance on Twitter: The case of the TAP pipeline

This research explores a new methodological path for doing green cultural criminological research via social media. It provides original case-study data and aims to stimulate further empirical and theoretical debate. In particular, the study explores how Twitter users have represented the harms related to an ongoing pipeline project in Italy (referred to as TAP), and the resistance to those harms. To these ends, it offers a virtual and visual ethnography of Twitter posts and posted images

Il trattamento del diabete mellito di tipo 2 nei pazienti affetti da malattia renale cronica: cosa aspettarsi dai nuovi ipoglicemizzanti orali

Worldwide, an estimated 200 million people have chronic kidney disease (CKD), whose most common causes include hypertension, arteriosclerosis, and diabetes. About 40% of patients with diabetes develop CKD. Intensive blood glucose control through pharmacological intervention can delay CKD progression. Standard therapies for the treatment of type 2 diabetes include metformin, sulfonylureas, meglitinides, thiazolidinediones and insulin. While these drugs have an important role in the management of type 2 diabetes, only the thiazolidinedione pioglitazone can be used across the spectrum of CKD (stages 2\u20135) and without dose adjustment. Newer therapies, particularly dipeptidyl peptidase-IV inhibitors, glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter-2 inhibitors are increasingly being used in the treatment of type 2 diabetes. However, a major consideration is whether these newer therapies can also be used safely and effectively across the spectrum of renal impairment

High glucose up-regulates ENaC and SGK1 expression in HCD-cells

Background/Aim: Diabetic nephropathy is associated with progressive renal damage, leading to impaired function and end-stage renal failure. Secondary hypertension stems from a deranged ability of cells within the kidney to resolve and appropriately regulate sodium resorption in response to hyperglycaemia. However, the mechanisms by which glucose alters sodium re-uptake have not been fully characterised. Methods: Here we present RT-PCR, western blot and immunocytochemistry data confirming mRNA and protein expression of the serum and glucocorticoid inducible kinase (SGK1) and the a conducting subunit of the epithelial sodium channel (ENaC) in a model in vitro system of the human cortical collecting duct (HCD). We examined changes in expression of these elements in response to glucose challenge, designed to mimic hyperglycaemia associated with type 2 diabetes mellitus. Changes in Na+ concentration were assessed using single-cell microfluorimetry. Results: Incubation with glucose, the Ca2+-ionophore ionomycin and the cytokine TGF-beta 1 were all found to evoke significant and time-dependent increases in both SGK1 and alpha ENaC protein expression. These molecular changes were correlated to an increase in Na+-uptake at the single-cell level. Conclusion: Together these data offer a potential explanation for glucose-evoked Na+-resorption and a potential contributory role of SGK1 and ENaCs in development of secondary hypertension, commonly linked to diabetic nephropathy

Nomenclature for renal replacement therapy and blood purification techniques in critically ill patients: practical applications

This article reports the conclusions of the second part of a consensus expert conference on the nomenclature of renal replacement therapy (RRT) techniques currently utilized to manage acute kidney injury and other organ dysfunction syndromes in critically ill patients. A multidisciplinary approach was taken to achieve harmonization of definitions, components, techniques, and operations of the extracorporeal therapies. The article describes the RRT techniques in detail with the relevant technology, procedures, and phases of treatment and key aspects of volume management/fluid balance in critically ill patients. In addition, the article describes recent developments in other extracorporeal therapies, including therapeutic plasma exchange, multiple organ support therapy, liver support, lung support, and blood purification in sepsis. This is a consensus report on nomenclature harmonization in extracorporeal blood purification therapies, such as hemofiltration, plasma exchange, multiple organ support therapies, and blood purification in sepsis

Gli inibitori della Neprilisina nei pazienti affetti da Malattia Renale Cronica e Sindrome Cardio-Renale

I pazienti affetti da malattia renale cronica (CKD) presentano una maggiore incidenza di eventi cardiovascolari (acuti e cronici) che, a loro volta, comportano un rischio aumentato di progressione verso la malattia renale cronica terminale (end \u2013 stage renal disease \u2013 ESRD) L\u2019inibizione della neprilisina, oltre ad offrire un nuovo target terapeutico nei pazienti affetti da scompenso cardiaco, potrebbero rappresentare una strategia di potenziale miglioramento negli outcomes, sia cardio-vascolari che renali, dei pazienti affetti da CKD. L\u2019inibizione della neprilisina, favorendo una maggiore biodisponibilit\ue0 dei peptidi natriuretici atriali, determina un incremento della diuresi e della natriuresi, oltre ad esercitare un\u2019azione di inibizione del sistema renina \u2013 angiotensina \u2013 aldosterone (RAAS). L\u2019inibizione del RAAS, a sua volta, genera una serie di controregolazioni in grado di bilanciarne gli effetti sfavorevoli in corso di CKD e di insufficienza cardiaca (HF). L\u2019idea del blocco della neprilisina non \ue8 recentissima, ma i primi farmaci impiegati, essendo molecole di associazione con antagonisti dell\u2019angiotensina II (ARBs), risultavano gravati da un\u2019incidenza inammissibile di angioedema. Tra le molecole di ultima generazione in grado di esercitare un\u2019azione inibente specifica sul recettore della neprilisina e su quello dell\u2019angiotensina II, grazie alla associazione con il valsartan, vi \ue8 l\u2019LCZ696 (sacubitril/valsartan) che ha mostrato evidenti benefici sia nel trattamento dell\u2019ipertensione arteriosa che nell\u2019insufficienza cardiaca.Patients with chronic kidney disease (CKD) have a higher incidence of cardiovascular (acute and chronic) events, which in turn have an increased risk of progression to end-stage renal disease (ESRD) Inhibition of neprilysin, in addition to offering a new therapeutic target in patients with heart failure, could represent a potential improvement strategy in cardiovascular and renal outcome of patients with CKD. Inhibition of neprilysin by inhibiting the breakdown of natriuretic peptides, increases their bioavailability resulting in an increase in diuresis and sodium excretion and, in addition to exerting an inhibition of the renin-angiotensin-aldosterone (RAAS) system. Inhibition of RAAS, in turn, generates a series of counter-regulations that can balance the adverse effects present in CKD and heart failure (HF). The idea of blocking neprilysin is not very recent, but the first drugs used as inhibitors had an inadmissible incidence of angioedema. Among the latest generation molecules that can perform a specific inhibitory action on the neprilysin receptor and, at the same time, on the angiotensin II receptor thanks to the association with valsartan there is the LCZ696 (sacubitril / valsartan). This drug has shown promising benefits both in the treatment arterial hypertension and heart failure. It is hoped that equally positive effects may occur in CKD patients, particularly those with macroproteinuria

Gli inbitori della neprilisina nei pazienti affetti da malattia renale cronica sindrome cardio-renale

I pazienti affetti da malattia renale cronica (CKD) presentano una maggiore incidenza di eventi cardiovascolari (acuti e cronici) che, a loro volta, comportano un rischio aumentato di progressione verso la malattia renale cronica terminale (end \u2013 stage renal disease \u2013 ESRD) L\u2019inibizione della neprilisina, oltre ad offrire un nuovo target terapeutico nei pazienti affetti da scompenso cardiaco, potrebbero rappresentare una strategia di potenziale miglioramento negli outcomes, sia cardio-vascolari che renali, dei pazienti affetti da CKD. L\u2019inibizione della neprilisina, favorendo una maggiore biodisponibilit\ue0 dei peptidi natriuretici atriali, determina un incremento della diuresi e della natriuresi, oltre ad esercitare un\u2019azione di inibizione del sistema renina \u2013 angiotensina \u2013 aldosterone (RAAS). L\u2019inibizione del RAAS, a sua volta, genera una serie di controregolazioni in grado di bilanciarne gli effetti sfavorevoli in corso di CKD e di insufficienza cardiaca (HF). L\u2019idea del blocco della neprilisina non \ue8 recentissima, ma i primi farmaci impiegati, essendo molecole di associazione con antagonisti dell\u2019angiotensina II (ARBs), risultavano gravati da un\u2019incidenza inammissibile di angioedema. Tra le molecole di ultima generazione in grado di esercitare un\u2019azione inibente specifica sul recettore della neprilisina e su quello dell\u2019angiotensina II, grazie alla associazione con il valsartan, vi \ue8 l\u2019LCZ696 (sacubitril/valsartan) che ha mostrato evidenti benefici sia nel trattamento dell\u2019ipertensione arteriosa che nell\u2019insufficienza cardiaca.