A high-speed, low-power interleaved trace-back memory for Viterbi decoder

This paper presents a high-speed, low-power trace-back memory structure for a Viterbi decoder. The new memory is based on an array of registers connected with trace-back signals that decode the output bits on the fly. The trace-back memory is internally interleaved such that high-speed characteristic is achieved while low-power consumption is maintained. The structure is used together with appropriate clock and power-aware control signals. The design is 100% portable and is suitable for a SoftIP approach. Based on the AMS 0.35 /spl mu/m CMOS implementation the trace-back memory is estimated to consume energy of 232 pJ, which is 53.6% less than a conventional RAM based design, with a maximum throughput of 1.1 Gbps

A Viterbi decoder with low-power trace-back memory structure for wireless pervasive communications

This paper presents a new trace-back memory structure for Viterbi decoders that reduces power consumption by 63% compared to the conventional RAM based design. Instead of the intensive read and write operations as required in RAM based designs, the new memory is based on an array of registers connected with trace-back signals that decode the output bits on the fly. The structure is used together with appropriate clock and power-aware control signals. Based on a 0.35 /spl mu/m CMOS implementation the trace-back back memory consumes energy of 182 pJ

Developing an Appropriate Digital Hearing Aid for Low-Resource Countries: A Case Study

This paper reviews the development process and discusses the key findings which resulted from our multidisciplinary research team’s effort to develop an alternative digital hearing suitable for low-resource countries such as Thailand. A cost-effective, fully programmable digital hearing aid, with its specifications benchmarking against WHO’s recommendations, was systematically designed, engineered, and tested. Clinically it had undergone a full clinical trial that employed the outcome measurement protocol adopted from the APHAB, the first time implemented in Thai language. Results indicated that using the hearing aid improves user’s satisfaction in terms of ease of communication, background noises, and reverberation, with clear benefit after 3 and 6 months, confirming its efficacy. In terms of engineering, the hearing aid also proved to be robust, passing all the designated tests. As the technology has successfully been transferred to a local company for the production phase, we also discuss other challenges that may arise before the device can be introduced into the market

Developing an Appropriate Digital Hearing Aid for Low-Resource Countries: A Case Study

This paper reviews the development process and discusses the key findings which resulted from our multidisciplinary research team's effort to develop an alternative digital hearing suitable for low-resource countries such as Thailand. A cost-effective, fully programmable digital hearing aid, with its specifications benchmarking against WHO's recommendations, was systematically designed, engineered, and tested. Clinically it had undergone a full clinical trial that employed the outcome measurement protocol adopted from the APHAB, the first time implemented in Thai language. Results indicated that using the hearing aid improves user's satisfaction in terms of ease of communication, background noises, and reverberation, with clear benefit after 3 and 6 months, confirming its efficacy. In terms of engineering, the hearing aid also proved to be robust, passing all the designated tests. As the technology has successfully been transferred to a local company for the production phase, we also discuss other challenges that may arise before the device can be introduced into the market

Intracranial Administration of P Gene siRNA Protects Mice from Lethal Chandipura Virus Encephalitis

Background: In parts of India, Chandipura Virus (CHPV) has emerged as an encephalitis causing pathogen in both epidemic and sporadic forms. This pediatric disease follows rapid course leading to 55–75 % mortality. In the absence of specific treatment, effectiveness of RNA interference (RNAi) was evaluated. Methods and Findings: Efficacy of synthetic short interfering RNA (siRNA) or short hairpin RNA (shRNA) in protecting mice from CHPV infection was assessed. The target genes were P and M genes primarily because important role of the former in viral replication and lethal nature of the latter. Real time one step RT-PCR and plaque assay were used for the assessment of gene silencing. Using pAcGFP1N1-CHPV-P, we showed that P-2 siRNA was most efficient in reducing the expression of P gene in-vitro. Both quantitative assays documented 2logs reduction in the virus titer when P-2, M-5 or M-6 siRNAs were transfected 2hr post infection (PI). Use of these siRNAs in combination did not result in enhanced efficiency. P-2 siRNA was found to tolerate four mismatches in the center. As compared to five different shRNAs, P-2 siRNA was most effective in inhibiting CHPV replication. An extended survival was noted when mice infected intracranially with 100 LD 50 CHPV were treated with cationic lipid complexed 5 mg P-2 siRNA simultaneously. Infection with 10LD 50 and treatment with two doses of siRNA first, simultaneously and second 24 hr PI, resulted in 70 % survival. Surviving mice showed 4logs less CHPV titers in brain without histopathological changes or antibody response. Gene expression profiles of P-2 siRNA treated mice showed no interferon response. First dose of siRNA at 2h

Broad-Spectrum Antiviral Activity of RNA Interference against Four Genotypes of Japanese Encephalitis Virus Based on Single MicroRNA Polycistrons

Japanese encephalitis virus (JEV), a neurotropic mosquito-borne flavivirus, causes acute viral encephalitis and neurologic disease with a high fatality rate in humans and a range of animals. Small interfering RNA (siRNA) is a powerful antiviral agent able to inhibit JEV replication. However, the high rate of genetic variability between JEV strains (of four confirmed genotypes, genotypes I, II, III and IV) hampers the broad-spectrum application of siRNAs, and mutations within the targeted sequences could facilitate JEV escape from RNA interference (RNAi)-mediated antiviral therapy. To improve the broad-spectrum application of siRNAs and prevent the generation of escape mutants, multiple siRNAs targeting conserved viral sequences need to be combined. In this study, using a siRNA expression vector based on the miR-155 backbone and promoted by RNA polymerase II, we initially identified nine siRNAs targeting highly conserved regions of seven JEV genes among strains of the four genotypes of JEV to effectively block the replication of the JEV vaccine strain SA14-14-2. Then, we constructed single microRNA-like polycistrons to simultaneously express these effective siRNAs under a single RNA polymerase II promoter. Finally, these single siRNAs or multiple siRNAs from the microRNA-like polycistrons showed effective anti-virus activity in genotype I and genotype III JEV wild type strains, which are the predominant genotypes of JEV in mainland China. The anti-JEV effect of these microRNA-like polycistrons was also predicted in other genotypes of JEV (genotypes II and IV), The inhibitory efficacy indicated that siRNAs×9 could theoretically inhibit the replication of JEV genotypes II and IV

Homeobox transcription factor muscle segment homeobox 2 (Msx2) correlates with good prognosis in breast cancer patients and induces apoptosis in vitro

Introduction: The homeobox-containing transcription factor muscle segment homeobox 2 (Msx2) plays an important role in mammary gland development. However, the clinical implications of Msx2 expression in breast cancer are unclear. The aims of this study were to investigate the potential clinical value of Msx2 as a breast cancer biomarker and to clarify its functional role in vitro. Methods: Msx2 gene expression was first examined in a well-validated breast cancer transcriptomic dataset of 295 patients. Msx2 protein expression was then evaluated by immunohistochemistry in a tissue microarray (TMA) containing 281 invasive breast tumours. Finally, to assess the functional role of Msx2 in vitro, Msx2 was ectopically expressed in a highly invasive breast tumour cell line (MDA-MB-231) and an immortalised breast cell line (MCF10a), and these cell lines were examined for changes in growth rate, cell death and cell signalling. Results: Examination of Msx2 mRNA expression in a breast cancer transcriptomic dataset demonstrated that increased levels of Msx2 were associated with good prognosis (P = 0.011). Evaluation of Msx2 protein expression on a TMA revealed that Msx2 was detectable in both tumour cell nuclei and cytoplasm. Cytoplasmic Msx2 expression was associated with low grade tumours (P = 0.012) and Ki67 negativity (P = 0.018). Nuclear Msx2 correlated with low-grade tumours (P = 0.015), estrogen receptor positivity (P = 0.038), low Ki67 (P = 0.005) and high cyclin D1 expression (P = 0.037). Increased cytoplasmic Msx2 expression was associated with a prolonged breast cancer-specific survival (P = 0.049), recurrence-free survival (P = 0.029) and overall survival (P = 0.019). Ectopic expression of Msx2 in breast cell lines resulted in radically decreased cell viability mediated by induction of cell death via apoptosis. Further analysis of Msx2-expressing cells revealed increased levels of p21 and phosphorylated extracellular signal-regulated kinase (ERK) and decreased levels of Survivin and the 'split ends' (SPEN) protein family member RBM15. Conclusions: We conclude that increased Msx2 expression results in improved outcome for breast cancer patients, possibly by increasing the likelihood of tumour cell death by apoptosis

Area-time-power view of VLSI pipelined wave digital filters

Available from British Library Document Supply Centre-DSC:DXN048747 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo