a predicting model of pats performance in off design operating conditions

Abstract The aim of this work is to propose a predicting model for evaluating Pump-as-Turbines' (PaTs) performance in off-design operating conditions. The predicting model has been derived from an elaboration of experimental test data available in literature on a set of several pumps operating in reverse mode. The performance prediction capability of the model has been compared with the results of the Computational Fluid Dynamics (CFD) analysis of a centrifugal pump running in turbine mode for several operating conditions. The comparison of the performance predicted by the model and the ones obtained with the numerical analysis has allowed to evaluate the effectiveness of the proposed model, highlighting its pros and cons and possible improvements. In general, it is possible to conclude that the proposed model is able to correctly assess the work and the efficiency of the studied PaT within errors in the range of few percentage points, especially for operating conditions not so far from the designed one

Study of a Pump-as-Turbine (PaT) speed control for a Water Distribution Network (WDN) in South-Tyrol subjected to high variable water flow rates

Abstract The development of renewable energy technologies for producing clean energy has more and more become a priority worldwide. Research activities have not just to target the technological improvement of such systems, but they have also to consider their market deployment. In such a scenario, hydraulic machines, in particular Pumps-as-Turbines (PaTs), can play a key role in energy recovery applications. One of the main open issues of PaTs is the performance forecast in turbine mode, due to the lack of data from manufacturers, and their use in some applications with high flow rate and pressure variability, especially at part-load operating conditions like in energy recovery applications within Water Distribution Networks (WDNs). In this work, a MATLAB® Simulink model is developed for simulating a branch of the WDN located in Laives (South-Tyrol), where specific PaTs have been selected and used to substitute Pressure Reducing Valves (PRVs). A speed control by means of an inverter is performed due to the high variability of the flow rate inside the grid branch, allowing the machines to operate at their Best Efficiency Point (BEP). A preliminary analysis showed that it is possible to increase the energy production of about 23% with respect to a constant-speed machine, leading to a significant decrease of the PayBack Period (PBP)

technical and economic analysis of pumps as turbines pats used in an italian water distribution network wdn for electrical energy production

Abstract The use of renewable resources is fundamental for achieving the emissions reduction targets. Small-scale hydropower is a viable solution that has only partially been exploited so far for producing electrical energy in rural/remote zones and for recovering energy where there is availability of pressure gradients and flow rates, like in Water Distribution Networks (WDNs) or in other industrial processes. In this paper, Pumps-as-Turbines (PaTs) are studied as a potential energy recovery and pressure regulation device, considering the case study of the Egna municipality WDN, a city located in the North of Italy. An innovative analytical approach is used for selecting PaTs, depending on WDN operating data, and for forecasting the machine performance under varying operating conditions. A MATLAB® Simulink model is developed for simulating two different set-ups configurations and installation of PaTs. Finally, an economic analysis is performed by evaluating the potential energy recovery and the PayBack Periods (PBPs)

energy recovery in oil refineries through the installation of axial pumps as turbines pats in a wastewater sewer a case study

Abstract This paper analyses an energy recovery solution for the application in an oil refinery, which has undergone significant changes in the last decades due to the construction of different plants, services, storage and logistics systems. Nowadays, with the aim to reduce the water contamination close to the refinery, the local regulations imposed to introduce solutions for the treatment of the groundwater underneath the oil treatment plants. In order to reclaim the site and to safeguard the areas close to the oil refinery, an intervention named "Pump & Treat" was adopted by an Italian company which consists in pumping up the underground water and treating it to remove any trace of polluting agent. Subsequently, a part of the treated water is discharged, by gravity, into the sea through a wastewater sewer. An Axial-Flow Pump (AFP) is studied in both pump and turbine modes for being installed in the wastewater sewer of the analysed oil refinery. After evaluating the availability of flow rate and head, the design characteristics of a proper axial turbine were identified. Computational Fluid Dynamics (CFD) simulations of an AFP are performed in both pump and turbine modes. The obtained results were used for scaling down the hydraulic machine and for defining a new one, properly adapted for the wastewater sewer, as energy recovery unit. The selected axial Pump-as-Turbine (PaT) allowed to achieve an economic saving of about 1706 €/year, leading to a Pay-Back Period (PBP) of about 1 year and 10 months

Critical issues and opportunities of emergency psychiatry in Italian emergency departments

In Italy emergency physicians are the front line of care for patients with medical conditions such as trauma, heart attacks, strokes or psychiatric disorders. Triage represents the first clinical contact with the person to determine urgency of care, and includes initial risk assessment and determination of observation level. It is necessary to undertake mental health triage for all service users on entry to the Emergency Department (ED), alongside physical health triage. The recourse to emergency services for psychiatric complaints is increasing and ED providers are often the first contact a patient will have with psychiatric care. The organization of Italian EDs is constantly evolving under the pressure of various external forces (population aging, increasing use of new substances, immigration, choices of economic policy, and technological development). The psychiatric emergency service contact represents a key to addressing the presenting problem and it is a critical link for continuity of care. The management of psychiatric disorders is an evolving issue in Italy as in other countries. Research increasingly suggests the importance of specific training for EDs teams in order to provide appropriate handling in acute settings. Psychiatrists and ED physicians can – and should – play a fundamental role in promoting a targeted and shared training for emergency services to deal with crisis according to evidence-based medicine. Service organization, legal issues, safety, training and education are not well defined and established and still imply improvisation, while they deserve attention as fundamental prerequisite to implement specific treatment guidelines

The endophytic microbiome of X. fastidiosa susceptible and resistant olives

A multi-factorial strategy is required to co-exist with X. fastidiosa infections, which are devastating olive trees in the southern area of Apulia (Italy). Observations in the outbreak area can provide information on potential approaches for containment. Olive cvs Leccino and FS17 show lessened symptoms and host lower bacterial populations (1,2) than cvs Ogliarola salentina, Cellina di Nardò and Kalamata. We are evaluating whether microbial communities inhabiting the xylem vessels of olive cvs showing different susceptibilities to X. fastidiosa -infection play a role in resistance. To explore these endophytic microbiomes, a whole-metagenome shotgun analysis is currently ongoing. X. fastidiosa -infected and healthy olive plants of the cultivars FS17, Leccino and Kalamata, were selected from the same plot to limit the influence of diverse soil composition and crop management. Shotgun sequencing of DNA extracted from the xylem tissues will be used to investigate the microbiome community by bio-informatic analysis. Moreover, efforts to isolate culturable microorganisms to be used in antagonistic assays against X. fastidiosa, will be performed. Concurrently, the X. fastidiosa-biocontrol potency of Paraburkholderia phytofirmans PsJN strain, whose beneficial effects in the reduction of symptoms in Pierce’s Disease (3) have been recently described, are under evaluation. We are testing the ability of P. phytofirmans to colonise xylem vessels and interact with X. fastidiosa in tobacco and olive

Decreasing mortality with drotrecogin alfa in high risk septic patients A meta-analysis of randomized trials in adult patients with multiple organ failure and mortality >40%

Objective. Sepsis is a complex inflammatory disease, rising in response to infection. Drotrecogin alfa, approved in 2001 for severe sepsis, has been withdrawn from the market. The aim of this study was to assess if drotrecogin alfa-activated can reduce mortality in the more severe septic patients. Methods. We searched PubMed, Embase, Scopus, BioMedCentral, and in Clinicaltrials. gov databases to identify every randomized study performed on drotrecogin alfa-activated in any clinical setting in humans, without restrictions on dose or time of administration. Our primary end-point was mortality rate in high risk patients. Secondary endpoints were mortality in all patients, in patients with an Acute Physiology and Chronic Health Evaluation (APACHE) 2 score ≥ 25 and in those with an APACHE 2 score ≤25. Results. Five trials were identified and included in the analysis. They randomized 3196 patients to drotrecogin alfa and 3111 to the control group. Drotrecogin alfa was associated with a reduction in mortality (99/263 [37.6%] vs 115/244 [47.1%], risk ratios (RR) = 0.80[0.65; 0.98], p = 0.03) in patients with multiple organ failure and a mortality risk in the control group of >40%, but not in the overall population or in lower risk populations. Conclusions. In high risk populations of patients with multiple organ failure and a mortality of >40% in the control group, Drotrecogin alfa may still have a role as a lifesaving treatment. No beneficial effect in low risk patients was found. An individual patient meta-analysis including all randomized controlled trial on sepsis is warranted, along with new studies on similar drugs such as protein C zymogen

A novel mechanism of phenotypic heterogeneity in Creutzfeldt-Jakob disease

One of remarkable features of sporadic Creutzfeldt-Jakob disease (sCJD) is the great phenotypic variability. Understanding the molecular basis of this variability has important implications for the development of therapeutic approaches. It is well established that, in many cases, phenotypic heterogeneity of sCJD is under control of two determinants: the genotype at the methionine (M)/valine (V) polymorphic codon 129 of the human prion protein gene and the type, 1 or 2, of the pathogenic and disease-related form of the prion protein, PrPD. However, this scenario fails to explain the existence of distinct heterozygous sCJDMV2 subtypes, where heterogeneity occurs without any variation of the 129 allotype and PrPD type. One of these subtypes, denoted sCJDMV2C, associated with PrPD type 2, is characterized by widespread spongiform degeneration of the cerebral cortex (C). The second variant, denoted sCJDMV2K, features prominent deposition of PrPD amyloid forming kuru type (K) plaques. Here we used a mass spectrometry based approach to test the hypothesis that phenotypic variability within the sCJDMV2 subtype is at least partly determined by the abundance of 129 M and 129 V polymorphic forms of proteinase K-resistant PrPD (resPrPD). Consistent with this hypothesis, our data demonstrated a strong correlation of the MV2C and MV2K phenotypes with the relative populations of protease-resistant forms of the pathogenic prion proteins, resPrPD-129 M and resPrPD-129 V, where resPrPD-129 M dominated in the sCJDMV2C variant and resPrPD-129 V in the sCJDMV2K variant. This finding suggests an important, previously unrecognized mechanism for phenotypic determination in human prion diseases

An ancestral host defence peptide within human beta-defensin 3 recapitulates the antibacterial and antiviral activity of the full-length molecule

Host defence peptides (HDPs) are critical components of innate immunity. Despite their diversity, they share common features including a structural signature, designated “γ-core motif”. We reasoned that for each HDPs evolved from an ancestral γ-core, the latter should be the evolutionary starting point of the molecule, i.e. it should represent a structural scaffold for the modular construction of the full-length molecule, and possess biological properties. We explored the γ-core of human β-defensin 3 (HBD3) and found that it: (a) is the folding nucleus of HBD3; (b) folds rapidly and is stable in human serum; (c) displays antibacterial activity; (d) binds to CD98, which mediates HBD3 internalization in eukaryotic cells; (e) exerts antiviral activity against human immunodeficiency virus and herpes simplex virus; and (f) is not toxic to human cells. These results demonstrate that the γ-core within HBD3 is the ancestral core of the full-length molecule and is a viable HDP per se,since it is endowed with the most important biological features of HBD3. Notably, the small, stable scaffold of the HBD3 γ-core can be exploited to design disease-specific antimicrobial agents