On-line failure prediction in safety-critical systems

In safety-critical systems such as Air Traffic Control system, SCADA systems, Railways Control Systems, there has been a rapid transition from monolithic systems to highly modular ones, using off-the-shelf hardware and software applications possibly developed by different manufactures. This shift increased the probability that a fault occurring in an application propagates to others with the risk of a failure of the entire safety-critical system. This calls for new tools for the on-line detection of anomalous behaviors of the system, predicting thus a system failure before it happens, allowing the deployment of appropriate mitigation policies. The paper proposes a novel architecture, namely CASPER, for online failure prediction that has the distinctive features to be (i) black-box: no knowledge of applications internals and logic of the system is required (ii) non-intrusive: no status information of the components is used such as CPU or memory usage; The architecture has been implemented to predict failures in a real Air Traffic Control System. CASPER exhibits high degree of accuracy in predicting failures with low false positive rate. The experimental validation shows how operators are provided with predictions issued a few hundred of seconds before the occurrence of the failure

Probability of Potential Collision for Aircraft Encounters in High Density Airspaces

Failure Management consists of a set of functions that enable the detection, isolation, and correction of anomalous behavior in a monitored system trying to prevent system failures. An effective failure management should monitor the system looking for errors and faults that could end up in a failure and overcome such issues when they arise

Tungsten and Titanium Oxide Thin Films Obtained by the Sol-Gel Process as Electrodes in Electrochromic Devices

In this work, WO3 and TiO2 thin films have been obtained by the sol-gel spin coating method. The as-deposited samples were annealed at different annealing temperatures in the range between 100°C and 500°C. Micro-Raman spectroscopy confirmed that WO3 thin films annealed at 100°C and 300°C are amorphous while the crystallization process occurred at 500°C as established by the typical Raman modes of γ-WO3. Amorphous thin films of TiO2 have been obtained using annealing at 100°C and 300°C. The crystalline phase of the anatase-TiO2 has been obtained after the thermal treatment conducted at 500°C. The electrochromic devices were characterized by cyclic voltammetry and UV–Vis–NIR spectroscopy and it has been shown that the best configurations of the electrochromic devices studied in this work can be obtained by using the WO3 thin films amorphous, which means annealed at 100°C and 300°C, and TiO2 thin films crystalline, that is annealed at 500°C. The higher coloration efficiency values in the visible region (λ = 550 nm) and in the near-infrared region (λ = 1020 nm) support the idea that such devices could be used in order to control the light flux but also heat flux. It means that such electrochromic devices can be usefully employed as smart windows promoting energy and economic savings

Silk fibroin scaffolds enhance cell commitment of adult rat cardiac progenitor cells.

The use of three-dimensional (3D) cultures may induce cardiac progenitor cells to synthesize their own extracellular matrix (ECM) and sarcomeric proteins to initiate cardiac differentiation. 3D cultures grown on synthetic scaffolds may favour the implantation and survival of stem cells for cell therapy when pharmacological therapies are not efficient in curing cardiovascular diseases and when organ transplantation remains the only treatment able to rescue the patient’s life. Silk fibroin-based scaffolds may be used to increase cell affinity to biomaterials and may be chemically modified to improve cell adhesion. In the present study, porous, partially orientated and electrospun nanometric nets were used. Cardiac progenitor cells isolated from adult rats were seeded by capillarity in the 3D structures and cultured inside inserts for 21 days. Under this condition, the cells expressed a high level of sarcomeric and cardiac proteins and synthesized a great quantity of ECM. In particular, partially orientated scaffolds induced the synthesis of titin, which is a fundamental protein in sarcomere assembly

Remodeled eX vivo muscle engineered tissue improves heart function after chronic myocardial ischemia

: The adult heart displays poor reparative capacities after injury. Cell transplantation and tissue engineering approaches have emerged as possible therapeutic options. Several stem cell populations have been largely used to treat the infarcted myocardium. Nevertheless, transplanted cells displayed limited ability to establish functional connections with the host cardiomyocytes. In this study, we provide a new experimental tool, named 3D eX vivo muscle engineered tissue (X-MET), to define the contribution of mechanical stimuli in triggering functional remodeling and to rescue cardiac ischemia. We revealed that mechanical stimuli trigger a functional remodeling of the 3D skeletal muscle system toward a cardiac muscle-like structure. This was supported by molecular and functional analyses, demonstrating that remodeled X-MET expresses relevant markers of functional cardiomyocytes, compared to unstimulated and to 2D- skeletal muscle culture system. Interestingly, transplanted remodeled X-MET preserved heart function in a murine model of chronic myocardial ischemia and increased survival of transplanted injured mice. X-MET implantation resulted in repression of pro-inflammatory cytokines, induction of anti-inflammatory cytokines, and reduction in collagen deposition. Altogether, our findings indicate that biomechanical stimulation induced a cardiac functional remodeling of X-MET, which showed promising seminal results as a therapeutic product for the development of novel strategies for regenerative medicine

Aurora Kinase A expression predicts platinum-resistance and adverse outcome in high-grade serous ovarian carcinoma patients

High-Grade Serous Ovarian Carcinoma (HGSOC) is the predominant histotype of epithelial ovarian cancer (EOC), characterized by advanced stage at diagnosis, frequent TP53 mutation, rapid progression, and high responsiveness to platinum-based-chemotherapy. To date, standard first-line-chemotherapy in advanced EOC includes platinum salts and paclitaxel with or without bevacizumab. The major prognostic factor is the response duration from the end of the platinum-based treatment (platinum-free interval) and about 10-0 % of EOC patients bear a platinum-refractory disease or develop early resistance (platinum-free interval shorter than 6 months). On these bases, a careful selection of patients who could benefit from chemotherapy is recommended to avoid unnecessary side effects and for a better disease outcome. In this retrospective study, an immunohistochemical evaluation of Aurora Kinase A (AURKA) was performed on 41 cases of HGSOC according to platinum-status. Taking into account the number and intensity of AURKA positive cells we built a predictive score able to discriminate with high accuracy platinum-sensitive patients from platinum-resistant patients (p < 0.001). Furthermore, we observed that AURKA overexpression correlates to worse overall survival (p = 0.001; HR 0.14). We here suggest AURKA as new effective tool to predict the biological behavior of HGSOC. Particularly, our results indicate that AURKA has a role both as predictor of platinum-resistance and as prognostic factor, that deserves further investigation in prospective clinical trials. Indeed, in the era of personalized medicine, AURKA could assist the clinicians in selecting the best treatment and represent, at the same time, a promising new therapeutic target in EOC treatment

A multiscale hybrid model for pro-angiogenic calcium signals in a vascular endothelial cell

Cytosolic calcium machinery is one of the principal signaling mechanisms by which endothelial cells (ECs) respond to external stimuli during several biological processes, including vascular progression in both physiological and pathological conditions. Low concentrations of angiogenic factors (such as VEGF) activate in fact complex pathways involving, among others, second messengers arachidonic acid (AA) and nitric oxide (NO), which in turn control the activity of plasma membrane calcium channels. The subsequent increase in the intracellular level of the ion regulates fundamental biophysical properties of ECs (such as elasticity, intrinsic motility, and chemical strength), enhancing their migratory capacity. Previously, a number of continuous models have represented cytosolic calcium dynamics, while EC migration in angiogenesis has been separately approached with discrete, lattice-based techniques. These two components are here integrated and interfaced to provide a multiscale and hybrid Cellular Potts Model (CPM), where the phenomenology of a motile EC is realistically mediated by its calcium-dependent subcellular events. The model, based on a realistic 3-D cell morphology with a nuclear and a cytosolic region, is set with known biochemical and electrophysiological data. In particular, the resulting simulations are able to reproduce and describe the polarization process, typical of stimulated vascular cells, in various experimental conditions.Moreover, by analyzing the mutual interactions between multilevel biochemical and biomechanical aspects, our study investigates ways to inhibit cell migration: such strategies have in fact the potential to result in pharmacological interventions useful to disrupt malignant vascular progressio

Valutazione di parametri di benessere in allevamenti di bovine da latte a stabulazione libera e fissa in Toscana.

RIASSUNTO La questione del benessere animale in allevamento è una tematica molto dibattuta sia dall’opinione pubblica che dagli operatori del settore zootecnico. Il benessere della vacca da latte, come delle altre specie in produzione zootecnica, può risultare influenzato dal management aziendale e in particolare dal sistema di stabulazione. In questo comparto, nonostante l’orientamento verso strutture che prevedono la disponibilità per gli animali di apposite aree (di esercizio, di alimentazione, di riposo), la presenza di realtà che prevedono il mantenimento degli animali legati senza possibilità di movimento, è ancora diffusa. Questa privazione viene percepita come uno dei fattori più importanti nel limitare il benessere delle bovine da latte. Questo studio ha avuto come scopo la valutazione del benessere animale attraverso l’analisi di parametri immunologici, metabolici e stress correlati in vacche da latte pluripare di razza Frisona allevate a stabulazione fissa o libera. Lo studio ha interessato 155 vacche appartenenti a diciotto aziende dislocate nelle Province di Firenze, Massa. Lucca, Pisa e Livorno. Per ogni soggetto è stato prelevato un campione di sangue e di pelo e allo stesso tempo è stato valutato il Body Condition Score (BCS). Tutte le valutazioni e i prelievi sono stati effettuati di mattina e in presenza del personale di stalla per limitare il disturbo agli animali. Sono stati determinati i seguenti parametri: alanina-aminotransferasi (ALT), aspartato-aminotransferasi (AST), beta-idrossibutirrato (BHBA), azoto ureico (BUN), acidi grassi non esterificati (NEFA), proteine totali (TP), creatinina (Creat), calcio (Ca), cloro (Cl), potassio (K), fosforo inorganico (P), lisozima sierico (SL), aptoglobina (Hp), radicali liberi dell’ossigeno (OFR), cortisolo del pelo (Cortis) e BCS. I risultati hanno messo in evidenza che il tipo di stabulazione ha influenzato in maniera significativa ALT, AST, BUN, BHBA, Cl, SL, OFR. Tutti i parametri ricadono all’interno dei range di normalità ad eccezione di ALT, BUN, NEFA e SL. OFR è risultato più elevato negli allevamenti a stabulazione libera, molto probabilmente a causa del maggiore livello produttivo delle bovine allevate in questa tipologia. Il Cortisolo, nonostante sia risultato più alto nella posta fissa, non suscita particolari preoccupazioni riconducibili a stress cronico, poiché i valori ottenuti sono più bassi di molti riferiti in bibliografia. Dai risultati ottenuti emerge che la stabulazione fissa non sembra compromettere la salute e lo stato di benessere degli animali, probabilmente a seguito delle maggiori attenzioni sul singolo soggetto e sull’ambiente di allevamento da parte dell’uomo. ABSTRACT The increasing attention paid both by the legislator and the consumers regarding animal welfare has brought to the criticism towards the tie stall (TS) farming system of dairy cattle because it probably restricts the voluntary movement and the social behaviour of cows. The aim of this study was to compare the welfare of dairy cows reared in a tie-stall (TS) and open-stall (OS) system by metabolic, immunological and stress related parameters. The study involved 155 cows belonging to 18 farms located in some provinces of Tuscany. Blood samples were collected in the morning to estimate alanina-aminotransferase (ALT), aspartate-aminotransferase (AST), betahidroxibutirrate (BHBA), nitrogen ureic (BUN), non esterified fatty acids (NEFA), total proteins (TP), creatinine (Creat), calcium (Ca), Clorum (Cl), potassium (K), phosphorus (P), serum lisozyme (SL), haptoglobin (Hp), oxygen free radicals (OFR), and hair cortisol. At the same time a body condition score (BCS) was recorded. The results showed that the housing system affected various parameters such as ALT, AST, BHBA, BUN, Cl, SL, and OFR. Most of these parameters showed mean values within the range of reference without revealing any signs of suffering. An interesting outcome regarded the OFR level which was higher in the OS system probably as a consequence of the high productive effort. TS did not show a comparable overall situation with serious signs of welfare impairment. Cortisol, despite resulted higher in TS, did not raise particular concern related to chronic stress, since the obtained values were lower than data reported in literature. TS did not show a comparable overall situation with serious signs of welfare impairmen