This study examines the use of nonsystematic channel codes to obtain secure transmissions over the additive white Gaussian noise (AWGN) wire-tap channel. Unlike the previous approaches, we propose to implement nonsystematic coded transmission by scrambling the information bits, and characterize the bit error rate of scrambled transmissions through theoretical arguments and numerical simulations.We have focused on some examples of Bose-Chaudhuri-Hocquenghem (BCH) and low-density paritycheck (LDPC) codes to estimate the security gap, which we have used as a measure of physical layer security, in addition to the bit error rate. Based on a number of numerical examples, we found that such a transmission technique can outperform alternative solutions. In fact, when an eavesdropper (Eve) has a worse channel than the authorized user (Bob), the security gap required to reach a given level of security is very small. The amount of degradation of Eve's channel with respect to Bob's that is needed to achieve sufficient security can be further reduced by implementing scrambling and descrambling operations on blocks of frames, rather than on single frames. While Eve's channel has a quality equal in Ricerca 2010" funding program. to or better than that of Bob's channel, we have shown that the use of a hybrid automatic repeat-request (HARQ) protocol with authentication still allows achieving a sufficient level of security. Finally, the secrecy performance of some practical schemes has also been measured in terms of the equivocation rate about the message at the eavesdropper and compared with that of ideal codes.

This paper studies a variant of the McEliece cryptosystem able to ensure that the code used as the public key is no longer permutationequivalent to the secret code. This increases the security level of the public key, thus opening the way for reconsidering the adoption of classical families of codes, like Reed-Solomon codes, that have been longly excluded from the McEliece cryptosystem for security reasons. It is well known that codes of these classes are able to yield a reduction in the key size or, equivalently, an increased level of security against information set decoding; so, these are the main advantages of the proposed solution. We also describe possible vulnerabilities and attacks related to the considered system, and show what design choices are best suited to avoid them.

IMPORTANCE Myotonic dystrophy type 1 (DM1), the most common muscular dystrophy observed in adults, is a genetic multisystem disorder affecting several other organs besides skeletal muscle, including the brain. Cognitive and personality abnormalities have been reported; however, no studies have investigated brain functional networks and their relationship with personality traits/disorders in patients with DM1. OBJECTIVE To use resting-state functional magnetic resonance imaging to assess the potential relationship between personality traits/disorders and changes to functional connectivity within the default mode network (DMN) in patients with DM1. DESIGN, SETTING, AND PARTICIPANTS We enrolled 27 patients with genetically confirmed DM1 and 16 matched healthy control individuals. Patients underwent personality assessment using clinical interview and Minnesota Multiphasic Personality Inventory-2 administration; all participants underwent resting-state functional magnetic resonance imaging. Investigations were conducted at the Istituto di Ricovero e Cura a

A differential CpG methylation profile upstreamof the expanded CTG array at the DMPK locus has been reported\ud in patientswith myotonic dystrophy type 1 (DM1), suggesting that hypermethylation mightmodulate DM1 phenotype,\ud possibly affecting expression levels of DMPK and/or flanking genes. To clarify this issue,we characterized\ud by methylation sensitive high resolution melting (MS-HRM) the CpG methylation pattern of DNA sequences\ud flanking the pathological CTG expansion in 13 childhood-onset, 37 juvenile/adult-onset, 7 congenital DM1 patients\ud carrying uninterrupted CTG expansions and in 9 DM1 patients carrying variant expansions vs 30 controls.\ud Association of methylation status with disease features (nCTG, age, sex, MIRS, disease duration) was also\ud assessed. Finally, DMPK and SIX5 expression levels were evaluated in leukocytes from controls, methylated and\ud unmethylated DM1 patients.\ud Wefound hypermethylation involving upstreamsequences ofDM1 locus in patientswith uninterrupted CTG expansions\ud N1000 CTG and affected by a congenital or childhood onset form. Besides the n(CTG) and early disease\ud onset, hypermethylation was also significantly associated with maternal transmission.\ud On the other hand, hypermethylation involved the 3′ of the CTG array in DM1 patients carrying variant expansions.\ud DMPK and SIX5 expression did not significantly differ in methylated vs unmethylated DM1 patients. Our\ud results suggest that either the inherited size of the expanded allele and the presence of interruptions at the 3′\ud end are associated with a highly polarized pattern of CpG methylation at the DM1 locus and that, at least in leukocytes,\ud DM1 locus hypermethylation would not significantly affect DMPK or SIX5 expression