Differential electromagnetic attack on an FPGA implementation of elliptic curve cryptosystems

This paper describes a differential electromagnetic analysis attack performed on a hardware implementation of an elliptic curve cryptosystem. We describe the use of the distance of mean test. The number of measurements needed to get a clear idea of the right guess of the key-bit is taken as indication of the success of the attack. We can find the right key-bit by using only 2000 measurements. Also we give a electromagnetic model for the FPGA we use in our experiments. The amplitude, the direction and the position of the current on the FPGA’s lines with respect to the position of the antenna have an influence on the measured electromagnetic radiation in the FPGA’s surrounding area

Hyaluronic acid patellar peri-tentinous injection efficacy in sudden detrained rats

Introduzione L’attività fisica moderata seguita da improvvisa interruzione può influenzare le caratteristiche biologiche del tendine. Lo scopo del lavoro è stato quello di valutare l’attività cellulare, le caratteristiche istologiche, istomorfometriche e microstrutturali del tendine patellare e della sua entesi in condizioni di non allenamento (sedentarietà), allenamento ed improvviso arresto dell’attività fisica. E’ stato ipotizzato che un’iniezione peri-tendinea di acido ialuronico nelle settimane successive all’improvviso arresto dell’attività fisica potesse mantenere l’integrità strutturale e biologica del tendine patellare. Materiali e Metodi 24 ratti Sprague Dawley maschi di 8 settimane sono stati suddivisi in tre gruppi, allenati per 10 settimane, fino a 60-80% VO2max. I ratti sono stati suddivisi in tre gruppi: Non Allenati (6), Allenati (6), Disallenati (12). A 6 dei 12 ratti del gruppo Detrained, è stata praticata un’infiltrazione peri-tendinea a nel tendine patellare destro di 300 μl di acido ialuronico, mentre nei rimanenti 6, è stata praticata l’infiltrazione con soluzione fisiologica. I tendini rotulei espiantati sono stati valutati con coltura cellulare, valutazione biologica molecolare, valutazioni morfologiche microstrutturali, proliferazione, conta ed attività cellulare. Risultati I risultati in vitro hanno evidenziato vitalità e conta cellulare simili fra i Gruppi Trained e Detrained-HA con un incremento significativo del metabolismo cellulare rispetto agli altri Gruppi. La cellularità ha mostrato valori maggiori nei Gruppi Non Allenati e Detrained-NaCl ove si è osservata una biosintesi del collagene III superiore ai Gruppi Trained e Detrained-HA. Contrariamente, la produzione di collagene I e II presentava valori maggiori nei Gruppi Trained e Detrained-HA suggerendo una superiore efficienza tessutale e metabolica di questi ultimi. Conclusioni Questi risultati confermano che l’allenamento ed il suo improvviso arresto hanno effetti sulla struttura tendinea patellare di ratto e che l’iniezione peritendinea di acido ialuronico nel periodo di inattività ha effetti significativi su metabolismo cellulare e sul tendine rispetto al trattamento con soluzione fisiologica.Introduction Different conditions may alter tendon characteristics. Clinical evidence suggests that tendon injuries are more frequent in athletes that change type, intensity and duration of training. Aim of the study was the assessment of training and especially detraining on the patellar tendon (PT) and its enthesis. We also hypotized that peri-tendineous injection with Ialuronic acid in detrained rats could prevent structural tendon integrity. Materials and Methods: 24 male adult Sprague-Dawley rats were divided into 3 groups: 18 rats were trained on a treadmill for 10 weeks. Of these, 6 rats were euthanized immediately after training (trained group), 12 were caged without exercise for 4 weeks before being injected in peri patellar tendon tissue, 1 group with Ialuronic acid (de-trained HA group) and the other with Saline solution and then euthanized (de-trained Saline group). The remaining 6 rats used as controls (untrained rats). Patellar tendons were evaluated with cellular coltures, molecular biological evaluation, microstructural morphologic evaluation, cellular proliferation, cellular number and activity. Results In vitro results showed cells vitality and number similar between Trained and Detrained-HA groups with an increased significance cellular methabolism vs the others groups. Cellularity showed better values in Non Trained and Detrained-NaCl Groups where we saw superior collagen III biosinthesis vs Trained and Detrained-HA Groups. On the other side Collagen I and II showed better values in Trained and Detrained-HA suggesting a better tissue activity of Detrained-HA Group. Conclusion Sudden interruption of physical activity has a negative effect on tendons and peri-tendineous patellar injection with Ialuronic Acid can represent a protective tendon therapy after a sudden detraining period

Candida albicans-produced farnesol stimulates Pseudomonas quinolone signal production in LasR-defective Pseudomonas aeruginosa strains

Candida albicans has been previously shown to stimulate the production of Pseudomonas aeruginosa phenazine toxins in dual-species colony biofilms. Here, we report that P. aeruginosa lasR mutants, which lack the master quorum sensing system regulator, regain the ability to produce quorum-sensing-regulated phenazines when cultured with C. albicans. Farnesol, a signalling molecule produced by C. albicans, was sufficient to stimulate phenazine production in LasR− laboratory strains and clinical isolates. P. aeruginosa ΔlasR mutants are defective in production of the Pseudomonas quinolone signal (PQS) due to their inability to properly induce pqsH, which encodes the enzyme necessary for the last step in PQS biosynthesis. We show that expression of pqsH in a ΔlasR strain was sufficient to restore PQS production, and that farnesol restored pqsH expression in ΔlasR mutants. The farnesol-mediated increase in pqsH required RhlR, a transcriptional regulator downstream of LasR, and farnesol led to higher levels of N-butyryl-homoserine lactone, the small molecule activator of RhlR. Farnesol promotes the production of reactive oxygen species (ROS) in a variety of species. Because the antioxidant N-acetylcysteine suppressed farnesol-induced RhlR activity in LasR− strains, and hydrogen peroxide was sufficient to restore PQS production in las mutants, we propose that ROS are responsible for the activation of downstream portions of this quorum sensing pathway. LasR mutants frequently arise in the lungs of patients chronically infected with P. aeruginosa. The finding that C. albicans, farnesol or ROS stimulate virulence factor production in lasR strains provides new insight into the virulence potential of these strains

Provably Secure Double-Block-Length Hash Functions in a Black-Box Model

In CRYPTO’89, Merkle presented three double-block-length hash functions based on DES. They are optimally collision resistant in a black-box model, that is, the time complexity of any collision-finding algorithm for them is Ω(2^<l/2>) if DES is a random block cipher, where l is the output length. Their drawback is that their rates are low. In this article, new double-block-length hash functions with higher rates are presented which are also optimally collision resistant in the blackbox model. They are composed of block ciphers whose key length is twice larger than their block length