Self-checking on-line testable static RAM

This is a fault-tolerant random access memory for use in fault-tolerant computers. It comprises a plurality of memory chips each comprising a plurality of on-line testable and correctable memory cells disposed in rows and columns for holding individually addressable binary bits and provision for error detection incorporated into each memory cell for outputting an error signal whenever a transient error occurs therein. In one embodiment, each of the memory cells comprises a pair of static memory sub-cells for simultaneously receiving and holding a common binary data bit written to the memory cell and the error detection provision comprises comparator logic for continuously sensing and comparing the contents of the memory sub-cells to one another and for outputting the error signal whenever the contents do not match. In another embodiment, each of the memory cells comprises a static memory sub-cell and a dynamic memory sub-cell for simultaneously receiving and holding a common binary data bit written to the memory cell and the error detection provision comprises comparator logic for continuously sensing and comparing the contents of the static memory sub-cell to the dynamic memory sub-cell and for outputting the error signal whenever the contents do not match. Capability for correction of errors is also included

Covert6: A Tool to Corroborate the Existence of IPv6 Covert Channels

Covert channels are any communication channel that can be exploited to transfer information in a manner that violates the system’s security policy. Research in the field has shown that, like many communication channels, IPv4 and the TCP/IP protocol suite have been susceptible to covert channels, which could be exploited to leak data or be used for anonymous communications. With the introduction of IPv6, researchers are acutely aware that many vulnerabilities of IPv4 have been remediated in IPv6. However, a proof of concept covert channel system was demonstrated in 2006. A decade later, IPv6 and its related protocols have undergone major changes, which has introduced a need to reevaluate the current state of covert channels within IPv6. The current research demonstrates the corroboration of covert channels in IPv6 by building a tool that establishes a covert channel against a simulated enterprise network. This is further validated against multiple channel criteria

Ballistic Performance of Alumina and Zirconia-toughened Alumina Against 7.62 Armour Piercing Projectile

A study was carried out to compare the ballistic performance of high purity alumina and zirconia-toughened alumina (ZTA) using depth of penetration (DoP) test configuration against 7.62 mm armour piercing (AP) ammunition. The effect of tile thickness on the differential efficiency factor (DEF) was studied for tile thickness in the range of 3 mm to 6 mm for alumina tiles and 3 mm to 5 mm for ZTA tiles. The DEF is found to increase as tile thickness increases. An analysis on the failed shots showed that the residual shot weight does not follow a single linear relationship with ceramic tile thickness unlike the residual DoP for all thicknesses of tiles. Post-ballistic analysis on ceramic powder for particle size distribution was carried out and the results are presented.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.477-483, DOI:http://dx.doi.org/10.14429/dsj.64.674

Comparison of experimental and numerical sloshing loads in partially filled tanks

Sloshing phenomenon consists in the movement of liquids inside partially filled tanks, whichgenerates dynamic loads on the tank structure. Resulting impact pressures are of great importance in assessingstructural strength, and their correct evaluation still represents a challenge for the designer due to the highnonlinearities involved, with complex free surface deformations, violent impact phenomena and influence of airtrapping. In the present paper a set of two-dimensional cases for which experimental results are available areconsidered to assess merits and shortcomings of different numerical methods for sloshing evaluation, namely twocommercial RANS solvers (FLOW-3D and LS-DYNA), and two own developed methods (Smoothed ParticleHydrodynamics and RANS). Impact pressures at different critical locations and global moment induced by watermotion for a partially filled tank with rectangular section having a rolling motion have been evaluated and resultsare compared with experiments

Leggere le Indicazioni. Riflessioni e proposte per la scuola dell'infanzia

Il volume presenta il testo delle indicazioni nazionali per il curricolo della scuola dell'infanzia e del primo ciclo d'istruzione, pubblicato in forma ufficiale dal Ministero dell'Istruzione nel 2013, e ne propone un commento per quanto riguarda la parte relativa alla scuola dell'infanzia, mettendo a fuoco alcune tematiche cruciali: l'idea di scuola, di relazione educativa, di contesto, di continuità, di attività professional

Nanoscale magnetic field mapping with a single spin scanning probe magnetometer

We demonstrate quantitative magnetic field mapping with nanoscale resolution, by applying a lock-in technique on the electron spin resonance frequency of a single nitrogen-vacancy defect placed at the apex of an atomic force microscope tip. In addition, we report an all-optical magnetic imaging technique which is sensitive to large off-axis magnetic fields, thus extending the operation range of diamond-based magnetometry. Both techniques are illustrated by using a magnetic hard disk as a test sample. Owing to the non-perturbing and quantitative nature of the magnetic probe, this work should open up numerous perspectives in nanomagnetism and spintronics

Antimicrobial Peptides Human Beta-Defensin-2 and -3 Protect the Gut During Candida albicans Infections Enhancing the Intestinal Barrier Integrity: In Vitro Study

The intestinal mucosa is composed of a monolayer of epithelial cells, which is highly polarized and firmly united to each other thanks to the presence of proteins complexes, called Tight junctions (TJs). Alteration of the mucus layer and TJs causes an increase in intestinal permeability, which can lead to a microbial translocation and systemic disorders. Candida albicans, in addition to its role of commensal, is an opportunistic pathogen responsible for disseminated candidiasis, especially in immunocompromised subjects where the dysbiosis leads to damage of the intestinal mucosal barrier. In this work, we used a line of intestinal epithelial cells able to stably express the genes that encodes human beta defensin-2 (HBD-2) and -3 (HBD-3) to monitor the invasion of C. albicans in vitro. Defensins are a group of antimicrobial peptides (AMPs) found in different living organisms, and are involved in the first line of defense in the innate immune response against pathogens. The results obtained show that the presence of antimicrobial peptides improves the expression of TJs and increases the Trans Epithelial Electrical Resistence value. In addition, the invasive ability of C. albicans in transfected cells is significantly reduced, as well as the expression levels of genes involved in the apoptotic pathway. Through the study of interaction between antimicrobial peptides and microbiota we will be able in the future to better understand the mechanisms by which they exert the host defense function against intestinal pathogens

An alleged hoard of third century Alexandrian tetradrachms

Un ripostiglio di tetradrammi alessandrini viene pubblicat

A Study Comparison of Supraglottic Airway Devices I-Gel and ILMA (Intubating Laryngeal Mask Airway) for Ease of Insertion and as Conduit for Blind Endotracheal Intubation: A Prospective Comparative study

BACKGROUND : Tracheal intubation with Macintosh laryngoscope is considered gold standard in airway management. Supraglottic airway devices [SADS] are helpful in difficult airways and emercency life threatening situations. They are considered alternative to Endotracheal Tube and face mask for ventilation. They induce reduced stress response as compared to laryngoscopy and intubation. They can be easily inserted by staffs as it requires minimal training especially during Cardiopulmonary Resuscitation[CPR].They are associated with lower incidence of postoperative sore throat. Some SADS like ILMA and I-GEL allow for subsequent tracheal intubation for management of airway.This study is designed to evaluate the quality and ease of insertion of ILMA and IGEL and also Feasibility of blind endotracheal intubation using this devices. METHOD : 60 patients posted for surgical procedures under general anaesthesia. Patients fulfilling inclusion criteria were included in the study and were enrolled and analysed. Patients induced with appropriate Induction gents and Non depolarizing muscle relaxants and ventilated for 3 min prior to SAD insertion and again ventilated for one minute prior to blind ETT intubation. Group A – ILMA ( 30 ) inserted after 3 min ventilation followed by blind ETT intubation. Group B – I GEL (30) inserted after 3 min ventilation followed by blind ETT intubation. Variables such as Ease of insertion ,Number of attempts and Duration of insertion of SADS , Number of attempts and Duration of blind ETT insertion and Postoperative sorethroat, dysphagia etc. were compared. The collected data were statistically analysed and tabulated . RESULTS : The statistical analysis tools used in this study for the comparison of demographic variables, ease of insertion, number of attempts and duration of insertion of SAD, number of attempts and duration for ETT insertion, failure and postoperative sore throat and dysphagia were Chi square test and Fishers exact test. The p value derived for ease of insertion , number of attempts ,and duration of insertion of SGADS I-GEL and ILMA were p < 0.001 favouring I-GEL. Likewise the p value derived for number of attempts and duration for ETT insertion through I-GEL and ILMA were p< 0.0001 favouring ILMA. The p value derived for incidence of postoperative sore throat and dysphagia was p< 0.0125, favouring I-GEL. CONCLUSION : It was concluded that from above results that I-GEL is a better device for emergency rescue ventilation because of its ease of insertion and lesser incidence of postoperative sore throat and dysphagia as compared to ILMA whereas ILMA is a better device for blind endotracheal intubation compared to I-GE

Antimicrobial peptide human β-defensin-2 improves in vitro cellular viability and reduces pro-inflammatory effects induced by enteroinvasive Escherichia coli in Caco-2 cells by inhibiting invasion and virulence factors’ expression

Escherichia coli is one of the commensal species most represented in the intestinal microbiota. However, there are some strains that can acquire new virulence factors that enable them to adapt to new intestinal niches. These include enteroinvasive E. coli (EIEC) that is responsible for the bacillary dysentery that causes severe diarrheal symptoms in both children and adults. Due to the increasing onset of antibiotic resistance phenomena, scientific research is focused on the study of other therapeutic approaches for the treatment of bacterial infections. A promising alternative could be represented by antimicrobial peptides (AMPs), that have received widespread attention due to their broad antimicrobial spectrum and low incidence of bacterial resistance. AMPs modulate the immune defenses of the host and regulate the composition of microbiota and the renewal of the intestinal epithelium. With the aim to investigate an alternative therapeutic approach, especially in the case of antibiotic resistance, in this work we created a line of intestinal epithelial cells able to express high concentrations of AMP human β-defensin-2 (HBD-2) in order to test its ability to interfere with the pathogenicity mechanisms of EIEC. The results showed that HBD-2 is able to significantly reduce the expression of the proinflammatory cytokines by intestinal epithelial cells, the invasiveness ability of EIEC and the expression of invasion-associated genes