Distributed Double Differential Space-Time Coding with Amplify-and-Forward Relaying

This paper provides the double differentially modulated distributed space-time coding for amplify-andforward (AF) relaying cooperative communications system under time-varying fading channels. In many wireless systems, the communication terminals are mobile. In such case, frequency offsets arise subjected to Doppler’s effect and frequency mismatch amongst the terminals’ local oscillators. The double differential coding is proposed to overcome the problem of frequency offsets that present in the channel due to the rapidly fast moving nodes. The advantage of the double differential is that the scheme requires neither channel nor frequency offset knowledge for decoding process at the desired destination. However, the conventional two-codeword approach fails to perform and leads to error floor, a region where the error probability performance curve flattens for high signal-to-noise ratio (SNR) regime in fast fading environment. Hence, a low complexity multiple-codeword double differential sphere decoding (MCDDSD) is proposed. The simulation results show that the proposed MCDDSD significantly improve the system performance in time-varying environment

Sequence analysis and gene expression of putative oil palm chitinase and chitinase-like proteins in response to colonization of Ganoderma boninense and Trichoderma harzianum

Chitinases are glycosyl hydrolases that cleave the β-1,4-glycosidic linkages between N-acetylglucosamine residues in chitin which is a major component of fungal cell wall. Plant chitinases hydrolyze fungal chitin to chitin oligosaccharides that serve as elicitors of plant defense system against fungal pathogens. However, plants synthesize many chitinase isozymes and some of them are not pathogenesis-related. In this study, three full-length cDNA sequences encoding a putative chitinase (EgChit3-1) and two chitinase-like proteins (EgChit1-1 and EgChit5-1) have been cloned from oil palm (Elaeis guineensis) by polymerase chain reaction (PCR). The abundance of these transcripts in the roots and leaves of oil palm seedlings treated with Ganoderma boninense (a fungal pathogen) or Trichoderma harzianum (an avirulent symbiont), and a combination of both fungi at 3, 6 and 12 weeks post infection were profiled by real time quantitative reverse-transcription (qRT)-PCR. Our findings showed that the gene expression of EgChit3-1 increased significantly in the roots of oil palm seedlings treated with either G. boninense or T. harzianum and a combination of both; whereas the gene expression of EgChit1-1 in the treated roots of oil palm seedlings was not significantly higher compared to those of the untreated oil palm roots. The gene expression of EgChit5-1 was only higher in the roots of oil palm seedlings treated with T. harzianum compared to those of the untreated oil palm roots. In addition, the gene expression of EgChit1-1 and EgChit3-1 showed a significantly higher gene expression in the leaf samples of oil palm seedlings treated with either G. boninense or T. harzianum

Multiple Symbol Double Differential Transmission for Amplify-and-Forward Cooperative Diversity Networks in Time-Varying Channel

In the cooperative diversity wireless networks, the task to perform cooperation communication amongst neighbouring nodes is very challenging. Subjected to rapidly increasing mobility of the nodes i.e. wireless devices in fast moving vehicles and trains, at the destination end the receiver may not ideally estimate the channel characteristics and frequency offsets. Due to these circumstances which results in time-varying channels, the performance network degrades drastically. In order to enhance the performance in such environment, Double Differential (DD) modulation employing multiple symbol based detection is proposed which takes mobility environment of different nodes into consideration. By utilizing the DD transmission approach, the channel properties and frequency offset estimation is omitted in the amplify-andforward cooperative networks. The MATLAB simulation and numerical analysis on Bit Error Rate (BER) are carried out with consideration on considering flat-fading (i.e. the frequency non-selective) Rayleigh channels and when frequency offsets. The results depict that the proposed method over fading channels without channel estimation requirements and in the presence of frequency offsets performs better as compared to the conventional DD transmission. Optimized power allocation is also carried out to enhance the network performance by minimizing the BER analytical expression. It is demonstrated that the proposed power allocation scheme offers enhancement over the equally distributed power allocation approach

Engineering Lactococcus lactis as a cell factory for the production of limonene

Limonene is a plant monoterpene which contributes significantly to the scent of most essential oils due to its pleasant fragrance. The compound had been reported to have anti-cancer properties against several types of cancer including colorectal cancer. However, the production of this compound in nature is limited because it is produced as a secondary metabolite. To overcome these challenges, Lactococcus lactis was developed as a heterologous host for the production of limonene. A synthesized limonene synthase (LS) from Mentha spicata (mint) was cloned into L. lactis NZ9000. Western blot analysis using mouse IgG His-Tag monoclonal antibody showed successful LS expression by L. lactis at the size of ~55 kDa. GC-MS analysis results showed that limonene production was optimum after 24 h of induction (~8.0 ppm). Metabolic engineering was attempted to enhance the limonene production by overexpression of lactococcal 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) and mevalonate kinase (mvk) genes in the bacterial host. The recombinant L. lactis carrying pNZ:LSMM plasmid successfully enhanced the limonene production to two-fold (~15.1 ppm) after 24 h of induction. The outcomes of this study show the potential of L. lactis to produce plant proteins and bioactive compounds production, which prospectively leads to an oral delivery system for anti-cancer compounds

Interference Screw vs. Suture Anchor Fixation for Open Subpectoral Biceps Tenodesis: Does it Matter?

<p>Abstract</p> <p>Background</p> <p>Bioabsorbable interference screw fixation has superior biomechanical properties compared to suture anchor fixation for biceps tenodesis. However, it is unknown whether fixation technique influences clinical results.</p> <p>Hypothesis</p> <p>We hypothesize that subpectoral interference screw fixation offers relevant clinical advantages over suture anchor fixation for biceps tenodesis.</p> <p>Study Design</p> <p>Case Series.</p> <p>Methods</p> <p>We performed a retrospective review of a consecutive series of 88 patients receiving open subpectoral biceps tenodesis with either interference screw fixation (34 patients) or suture anchor fixation (54 patients). Average follow up was 13 months. Outcomes included Visual Analogue Pain Scale (0–10), ASES score, modified Constant score, pain at the tenodesis site, failure of fixation, cosmesis, deformity (popeye) and complications.</p> <p>Results</p> <p>There were no failures of fixation in this study. All patients showed significant improvement between their preoperative and postoperative status with regard to pain, ASES score, and abbreviated modified Constant scores. When comparing IF screw versus anchor outcomes, there was no statistical significance difference for VAS (p = 0.4), ASES score (p = 0.2), and modified Constant score (P = 0.09). One patient (3%) treated with IF screw complained of persistent bicipital groove tenderness, versus four patients (7%) in the SA group (nonsignificant).</p> <p>Conclusion</p> <p>Subpectoral biceps tenodesis reliably relieves pain and improves function. There was no statistically significant difference in the outcomes studied between the two fixation techniques. Residual pain at the site of tenodesis may be an issue when suture anchors are used in the subpectoral location.</p

Accreditation Handbook

This handbook is a reference for the faculty, academic and administrative staff on the process and procedures involved in preparing and obtaining accreditation. This handbook also serves as a valuable guide for the faculty to develop an assessment plan in the process of future accreditation

Accreditation Handbook

This handbook is a reference for the faculty, academic and administrative staff on the process and procedure involved in preparing and obtaining accreditation. This handbook also serves as a valuable guide for the faculty to develop an assessment plan in the process of the future accreditation