Memorial University of Newfoundland

About: Memorial University of Newfoundland is a education organization based out in St. John's, Newfoundland and Labrador, Canada. It is known for research contribution in the topics: Population & Gadus. The organization has 13818 authors who have published 27785 publications receiving 743594 citations. The organization is also known as: Memorial University & Memorial University of Newfoundland and Labrador.

WNT1 Mutations in Families Affected by Moderately Severe and Progressive Recessive Osteogenesis Imperfecta

Abstract: Osteogenesis imperfecta (OI) is a heritable disorder that ranges in severity from death in the perinatal period to an increased lifetime risk of fracture. Mutations in COL1A1 and COL1A2, which encode the chains of type I procollagen, result in dominant forms of OI, and mutations in several other genes result in recessive forms of OI. Here, we describe four recessive-OI-affected families in which we identified causative mutations in wingless-type MMTV integration site family 1 (WNT1). In family 1, we identified a homozygous missense mutation by exome sequencing. In family 2, we identified a homozygous nonsense mutation predicted to produce truncated WNT1. In family 3, we found a nonsense mutation and a single-nucleotide duplication on different alleles, and in family 4, we found a homozygous 14 bp deletion. The mutations in families 3 and 4 are predicted to result in nonsense-mediated mRNA decay and the absence of WNT1. WNT1 is a secreted signaling protein that binds the frizzled receptor (FZD) and the coreceptor low-density lipoprotein-receptor-related protein 5 (LRP5). Biallelic loss-of-function mutations in LRP5 result in recessive osteoporosis-pseudoglioma syndrome with low bone mass, whereas heterozygous gain-of-function mutations result in van Buchem disease with elevated bone density. Biallelic loss-of-function mutations in WNT1 result in a recessive clinical picture that includes bone fragility with a moderately severe and progressive presentation that is not easily distinguished from dominant OI type III.

FPGA implementation of MD5 hash algorithm

Abstract: In information security, message authentication is an essential technique to verify that received messages come from the alleged source and have not been altered. A key element of authentication schemes is the use of a message authentication code (MAC). One technique to produce a MAC is based on using a hash function and is referred to as an HMAC. The Message Digest 5 (MD5) is one of the algorithms, which has been specified for use in Internet Protocol Security (IPSEC), as the basis for an HMAC. The input message may be arbitrarily large and is processed in 512-bit blocks by executing 64 steps involving the manipulation of 128-bit blocks. There is an increasing interest in high-speed cryptographic accelerators for IPSEC applications such as virtual private networks. As we show, it is reasonable to construct cryptographic accelerators using hardware implementations of HMACs based on a hash algorithm such as MD5. Two different architectures, iterative and full loop unrolling, of MD5 have been implemented using field programmable gate arrays (FPGAs). The performance of these implementations is discussed.