TRANSIENT RESPONSE OF SUPERCONDUCTING Pb MICROBRIDGES IRRADIATED BY PICOSECOND LASER PULSES AND ITS POTENTIAL APPLICATIONS

[[abstract]]The authors observed voltage pulses having half-widths of less than 500 ps generated by constant-current-biased superconducting Pb variable thickness microbridges driven normal by short (3 EM DASH 5 ps) light pulses. This represents a step to generate even shorter pulses, which according to an analysis of the Rothwarf-Taylor equations should be possible. The ultimate width should be equal to the phonon pair-breaking time which, for materials such as Nb, can be a few picoseconds. In addition to monitoring the voltage pulses directly use was made of a novel adoption of the optical autocorrelation technique having a time resolution limited only by the laser pulse width. It is pointed out that even shorter voltage pulses, and therefore greater potential for device applications, can be achieved by direct injection of quasiparticles.[[fileno]]2010127010023[[department]]物理

ON SECURITY OF A PRACTICAL THREE-PARTY KEY EXCHANGE PROTOCOL WITH ROUND EFfiCIENCY

[[abstract]]Recently, Chang proposed a practical three-party key exchange (C-3PEKE) protocol with round efficiency. Unfortunately, this paper shall show that C-3PEKE is not secure and suffers from off-line password guessing attacks

A new authenticated group key agreement in a mobile environment

[[abstract]]A group key agreement protocol enables a group of communicating parties over an untrusted, open network to come up with a common secret key. It is designed to achieve secure group communication, which is an important research issue for mobile communication. In 2007, Tseng proposed a new group key agreement protocol to achieve secure group communication for a mobile environment. Its security is based on the decisional Diffie-Hellman assumption. It remedies the security weakness of the protocol of Nam et al. in which participants cannot confirm that their contributions were actually involved in the group key. Unfortunately, Tseng's protocol is a nonauthenticated protocol that cannot ensure the validity of the transmitted messages. In this paper, the authors shall propose a new authenticated group key agreement to remedy it. It is based on bilinear pairings. We shall prove the security of the proposed protocol under the bilinear computational Diffie-Hellman assumption. It is also proven to a contributory group key agreement protocol

A new authentication protocol based on pointer forwarding for mobile communications

[[abstract]]A frequently moving mobile user in GSM must re-register at the HLR frequently, and, therefore, the signaling traffic is overhead and HLR database update cost raised. In this paper, the authors propose a new authentication protocol, based on pointer forwarding to reduce the HLR update cost and traffic load for the MS authentication protocol. The proposed protocol for GSM can achieve some objectives described in Introduction. Compared with other authentication protocols, our protocol is efficient

A secure e-auction scheme based on group signatures

[[abstract]]Recently, electronic auctions have been receiving more and more attention in the world of electronic commerce. The security and efficiency of electronic auctions are becoming important. We shall propose a securely sealed-bid auction scheme that uses our group signature scheme with the function of authenticated encryption. It can achieve the following goals: secrecy of bidding price, anonymity, verifiability, non-repudiation, and better performance

Do etoricoxib and indometacin have similar effects and safety for gouty arthritis? A meta-analysis of randomized controlled trials

Tzu-Min Lin,1,2,* Jia-En Chi,1,3,* Chi-Ching Chang,2,4,* Yi-No Kang1 1Center for Evidence-Based Medicine, Department of Education, Taipei Medical University Hospital, Taipei, Taiwan, Republic of China; 2Division of Rheumatology, Immunology and Allergy, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan, Republic of China; 3School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, Republic of China; 4Division of Allergy, Immunology and Rheumatology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, Republic of China *These authors contributed equally to this work Background: Gout, a common medical condition that causes pain, can be treated by painkillers and anti-inflammatories. Indometacin and etoricoxib are two such drugs. However, no synthesized evidence exists comparing etoricoxib with indometacin in treating patients with gout.Methods: We searched PubMed, Embase, Ovid MEDLINE, Web of Science, ScienceDirect, and the Cochrane Library without restrictions on language or publication date for potential randomized clinical trials comparing etoricoxib with indometacin for gout. The meta-analysis was conducted using a random-effects model.Results: Search results yielded 313 references from six electronic databases, four of which met the eligibility criteria. These four were randomized clinical trials, and they involved a total of 609 patients with gouty arthritis. No significant differences were observed in pain score change, tenderness, or swelling between etoricoxib and indometacin; the mean differences were −0.05 (95% CI, −0.21 to 0.10), −0.06 (95% CI, −0.18 to 0.05), and −0.04 (95% CI, −0.17 to 0.09). However, the pooled data revealed that significantly fewer overall adverse events occurred in the etoricoxib group (n=105, 33.5%) than in the indometacin group (n=130, 44.1%) and the risk ratio was 0.77 (95% CI, 0.62–0.94).Conclusion: Our meta-analysis revealed that etoricoxib and indometacin have similar effects on pain relief. However, etoricoxib has a significantly lower risk of adverse events than does indometacin, especially digestive system-related adverse events. Keywords: gout, etoricoxib, indometacin&nbsp

Deep level defect in Si-implanted GaN n +-p junction

The results of deep level transient spectroscopy (DLTS) experiments on GaN junctions, fabricated by silicon implantation, were discussed. An unusual appearance of a minority peak in the majority carrier DLTS spectra within the interfacial region of the junctions was observed. The presence of this minority peak suggested a high concentration of a deep level defect within the interfacial region.published_or_final_versio

Sprouty2 mediated tuning of signalling is essential for somite myogenesis

Background: Negative regulators of signal transduction cascades play critical roles in controlling different aspects of normal embryonic development. Sprouty2 (Spry2) negatively regulates receptor tyrosine kinases (RTK) and FGF signalling and is important in differentiation, cell migration and proliferation. In vertebrate embryos, Spry2 is expressed in paraxial mesoderm and in forming somites. Expression is maintained in the myotome until late stages of somite differentiation. However, its role and mode of action during somite myogenesis is still unclear. Results: Here, we analysed chick Spry2 expression and showed that it overlaps with that of myogenic regulatory factors MyoD and Mgn. Targeted mis-expression of Spry2 led to inhibition of myogenesis, whilst its C-terminal domain led to an increased number of myogenic cells by stimulating cell proliferation. Conclusions: Spry2 is expressed in somite myotomes and its expression overlaps with myogenic regulatory factors. Overexpression and dominant-negative interference showed that Spry2 plays a crucial role in regulating chick myogenesis by fine tuning of FGF signaling through a negative feedback loop. We also propose that mir-23, mir-27 and mir-128 could be part of the negative feedback loop mechanism. Our analysis is the first to shed some light on in vivo Spry2 function during chick somite myogenesis