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Mobility, Residual Energy, and Link Quality Aware Multipath Routing in MANETs with Q-learning Algorithm
No full textTo facilitate connectivity to the internet, the easiest way to establish communication infrastructure in areas affected by natural disaster and in remote locations with intermittent cellular services and/or lack of Wi-Fi coverage is to deploy an end-to-end connection over Mobile Ad-hoc Networks (MANETs). However, the potentials of MANETs are yet to be fully realized as existing MANETs routing protocols still suffer some major technical drawback in the areas of mobility, link quality, and battery constraint of mobile nodes between the overlay connections. To address these problems, a routing scheme named Mobility, Residual energy and Link quality Aware Multipath (MRLAM) is proposed for routing in MANETs. The proposed scheme makes routing decisions by determining the optimal route with energy efficient nodes to maintain the stability, reliability, and lifetime of the network over a sustained period of time. The MRLAM scheme uses a Q-Learning algorithm for the selection of optimal intermediate nodes based on the available status of energy level, mobility, and link quality parameters, and then provides positive and negative reward values accordingly. The proposed routing scheme reduces energy cost by 33% and 23%, end to end delay by 15% and 10%, packet loss ratio by 30.76% and 24.59%, and convergence time by 16.49% and 11.34% approximately, compared with other well-known routing schemes such as Multipath Optimized Link State Routing protocol (MP-OLSR) and MP-OLSRv2, respectively. Overall, the acquired results indicate that the proposed MRLAM routing scheme significantly improves the overall performance of the network. © 2019 by the authors
Investigation of possible rickettsial infection in patients with malaria
No full textRickettsioses are a common health problem in many geographical areas, including rural areas in Southeast Asia. Co-infection of rickettsioses and malaria has been reported in Africa, where common reservoir and vectors are available. In this study, blood samples of Malaysian patients microscopically positive (n=148) and negative (n=88) for malaria parasites (Plasmodium knowlesi, Plasmodium malariae, Plasmodium falciparum, and Plasmodium vivax) were screened for the presence of rickettsial DNA, using PCR assays targeting specific genes. A partial fragment of rickettsial ompB gene was successfully amplified and sequenced from a patient microscopically positive for Plasmodium spp. and PCR-positive for P. vivax. BLAST analysis of the ompB sequence demonstrated the highest sequence similarity (99.7% similarity, 408/409nt) with Rickettsia sp. RF2125 (Genbank accession no. JX183538) and 91.4% (374/409 nt) similarity with Rickettsia felis URRWXCal2 (Genbank accession no. CP000053). This study reports rickettsial infection in a malaria patient for the first time in the Southeast Asia region. © 2019, Malaysian Society for Parasitology. All rights reserved
A New Single Phase Single Switched-Capacitor Based Nine-Level Boost Inverter Topology With Reduced Switch Count and Voltage Stress
No full textBased on the concept of switched-capacitor based multilevel inverter topology, a new structure for a boost multilevel inverter topology has been recommended in this paper. The proposed topology uses 11 unidirectional switches with a single switched capacitor unit to synthesize nine-level output voltage waveform. Apart from the twice voltage gain, self-voltage balancing of capacitor voltage without any auxiliary method along with reduced voltage stress has been the main advantages of this topology. The merits of proposed topology have been analyzed through various comparison parameters including component counts, voltage stresses, cost and efficiency with a maximum value of 98.3%, together with the integration of switched capacitors into the topology following recent development. Phase disposition pulse width modulation (PD-PWM) technique and nearest level control PWM (NLC-PWM) have been used for the control of switches. Different simulation and hardware results with different operating conditions are included in the paper to demonstrate the performance of the proposed topology. © 2013 IEEE
C-band tunable performance of passively Q-switched erbium-doped fiber laser using Tin(IV) oxide as a saturable absorber
No full textWe report on the detailed study of wavelength tunability of passively Q-switched erbium doped fiber laser using Tin(IV) Oxide (SnO 2 ) as saturable absorber (SA). As a typical n-type semiconductor, SnO 2 has been widely used in gas sensors, oxidation catalyst, transparent conductor, and electrode materials in solar cell. Herein, we fabricated saturable absorber by compositing SnO 2 nanoparticle with polyvinyl alcohol (PVA). The SnO 2 -SA is incorporated in the laser cavity by sandwiching it between two fiber ferrules. Q-switched laser operation can be continuously tuned from 1521 to 1565 nm, with a wavelength tuning range of up to 45 nm, covering almost the entire C-band. Q-switched pulse parameters such as repetition rate, average power, pulse width, pulse energy, and peak power at different wavelengths were studied in detail. Our experimental results suggest that the SnO 2 -SA is a suitable and cost-effective solution for broadband tunable laser applications with relatively simple fabrication process. © 2019 Elsevier B.V
Fractal dimension methods to determine optimum EEG electrode placement for concentration estimation
No full textIn this study, fractal dimension approaches were used for analyzing EEG to determine the optimum electrode placement to distinguish between concentration and relaxation states. The EEG of participants was recorded from multiple electrode placements while under relaxed state and while in a state of heightened mental activity. Higuchi and Katz algorithms were applied to extract the fractal dimension FD indices of windowed segments of the EEG. These were then plotted in a graph, and a simple threshold was applied to best divide the indices of relaxation and concentration. The Higuchi algorithm was found to be better than Katz at distinguishing between relaxation and concentration, and P3 was found to be the best position to measure concentration, with P8 being a close contender. © 2017, The Natural Computing Applications Forum
Predictors of functional outcome in patients with stroke thrombolysis in a tertiary hospital in Malaysia
No full textINTRODUCTION Intravenous (IV) thrombolysis with alteplase (rt-PA) is effective in ischaemic stroke. The primary objective was to evaluate predictors of functional outcome in acute ischaemic stroke (AIS) patients treated with IV rt-PA. The secondary objective was to assess the outcome with the modified Rankin scale (mRS). We also examined the predictive value of the Totaled Health Risks in Vascular Events (THRIVE) score. METHODS AIS patients treated with IV rt-PA from February 2012 to August 2016 were recruited. Demographic data, National Institutes of Health Stroke Scale (NIHSS) scores, timing and neuroradiological findings were recorded. Patients received a dose of 0.9 mg/kg IV rt-PA within 4.5 hours of symptom onset. mRS score was evaluated at discharge and three months, and good and poor clinical outcomes were defined as scores of 0–2 and 3–6, respectively. Baseline THRIVE scores were assessed. RESULTS 36 patients received IV rt-PA. 20 (55.6%) patients had an mRS score of 0–2 at three months. Based on THRIVE score, 86.1% had a good or moderately good prognosis. On univariate analysis, poor outcome was associated with NIHSS score before rt-PA (p = 0.03), THRIVE score (p = 0.02), stroke subtype (p = 0.049) and diabetes mellitus (DM; p = 0.06). Multiple logistic regression showed that outcome was significantly associated with NIHSS score before rt-PA (p = 0.032) and DM (p = 0.010). CONCLUSION Our newly developed Malaysian IV rt-PA service is safe, with similar outcomes to the published literature. Functional outcome after thrombolysis was associated with baseline NIHSS score and DM. © 2019, Singapore Medical Association. All rights reserved
A cobalt oxide nanocubes interleaved reduced graphene oxide nanocomposite modified glassy carbon electrode for amperometric detection of serotonin
No full textCobalt oxide nanocubes incorporated with reduced graphene oxide (rGO-Co 3 O 4 ) was prepared by using simple one-step hydrothermal route. Crystallinity and structural characteristics of the nanocomposite were analyzed and confirmed using X-ray diffraction (XRD) and Raman analysis, respectively. The cubical shape of the Co 3 O 4 nanostructures and the distribution of Co 3 O 4 nanocubes on the surface of rGO sheets were identified through field emission scanning electron microscopy (FESEM) and energy dispersive X-ray (EDX) mapping analysis, respectively. Raman spectra depicted the presence of D and G bands for GO and rGO with different I D /I G values and thus confirmed the reduction of GO into rGO. The electrochemical study reflects that the rGO-Co 3 O 4 nanocomposite shows good electrocatalytic activity in oxidation of depression biomarker serotonin (5-HT) in phosphate buffer (pH 7.2). The detection of 5-HT was carried out by using rGO-Co 3 O 4 nanocomposite modified glassy carbon electrode under dynamic condition using amperometry technique with a linear range of 1–10 μM. The limit of detection and limit of quantification were calculated and found to be 1.128 and 3.760 μM, respectively with a sensitivity value of 0.133 μΑ·μM −1 . The sensor showed selectivity in the presence of different interferent species such as ascorbic acid, dopamine and uric acid. © 2019 Elsevier B.V
Translanguaging in an academic setting
No full textPakistan is home to diverse multilingual practices. However, these practices have not been extensively explored. This paper unpacks the interactive practices of a group of students in a university in Pakistan from the perspective of translanguaging. In particular, the paper examines the languages students use in informal class discussions in a university setting and explores their motivations for using different languages within this setting. Data collected through observations, video-recording and semi-structured interviews were ethnographically analysed. The findings indicate that although the Medium of Instruction at the university is English, the students displayed unconscious use of translanguaging in their discussions of mainly English and Pashto (their native language), and some Urdu (the national language). © 2019 Elsevier B.V
Pandoraea fibrosis sp. nov., a novel Pandoraea species isolated from clinical respiratory samples
No full textPandoraea species have been isolated from diverse environmental samples and are emerging important respiratory pathogens, particularly in people with cystic fibrosis (CF). In the present study, two bacterial isolates initially recovered from consecutive sputum samples collected from a CF patient and identified as Pandoraea pnomenusa underwent a polyphasic taxonomic analysis. The isolates were found to be Gram-negative, facultative anaerobic motile bacilli and subsequently designated as strains 6399 T (=LMG29626 T =DSM103228 T ) and 7641 (=LMG29627=DSM103229), respectively. Phylogenetic analysis based on 16S rRNA and gyrB gene sequences revealed that 6399 T and 7641 formed a distinct phylogenetic lineage within the genus Pandoraea. Genome sequence comparison analysis indicated that strains 6399 T and 7641 are clonal and share 100 % similarity, however, similarity to other type strains (ANIb 73.2–88.8 %, ANIm 83.5–89.9 % and OrthoANI 83.2– 89.3 %) indicates that 6399 T and 7641 do not belong to any of the reported type species. The major cellular fatty acids of 6399 T were C 16: 0 (32.1 %) C 17: 0 cyclo (18.7 %) and C 18: 1 !7c (14.5 %), while Q-8 was the only respiratory quinone detected. The major polar lipids identified were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The genomic DNA G+C content of 6399 T was 62.9 (mol%). Strain 6399 T can be differentiated from other members of Pandoraea by the absence of C 19: 0 !8c cyclo and by the presence of C 17: 0 !8c cyclo. Together our data show that the bacterial strains 6399 T and 7641 represent a novel species of the genus Pandoraea, for which the name Pandoraea fibrosis sp. nov. is proposed (type strain 6399 T ). © 2019 IUMS
Comparative static and shaking culture of metabolite derived from methyl red degradation by Lysinibacillus fusiformis strain W1B6
No full textThis paper reports on the comparative characteristics and properties of the metabolites derived from methyl red (MR) decolorization by Lysinibacillus fusiformis strain W1B6 under static and shaking conditions. A batch culture system was used to investigate the effect of aeration on azoreductase activity in the biodegradation process, transformation of colour removal and the metabolite products. Biodegradation analysis was monitored using Fourier transform infrared spectroscopy and high-performance liquid chromatography while metabolites were determined using gas chromatography- mass spectroscopy. Phytotoxicity and anti-microbial tests were also conducted to detect the toxicity of metabolites. The results showed that this strain grew more rapidly under shaking conditions while azoreductase activity increased more rapidly under static conditions. Despite that, no significant difference in the decolorization was observed under both static and shaking conditions with up to 96% and 93.6% decolorization achieved, respectively, within 4 h of incubation. MR was degraded into two fragmented compounds, i.e. 2-aminobenzoic acid and N,N-dimethyl-1.4-benzenediamine. The concentration of 2-amino benzoic acid was higher under static conditions resulting the biotransformation of 2-amino benzoic acid into methyl anthranilate more rapidly under static conditions. Other metabolites were also detected as intermediate biotransformation products and by-products. Less or no toxic effect was found in the metabolite degradation products under both culture conditions. © 2019 The Authors