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Mapping of tropical marine benthic habitat: Hydroacoustic classification of coral reefs environment using single-beam (RoxAnn™) system
No full textField studies on the performance and discussion of RoxAnn™ Acoustic Ground Discrimination System (AGDS) in discriminating different coral growth forms are often fractional and limited in tropical waters. The purpose of this study is to bridge the information gaps by conducting field surveys at the surrounding benthic habitats of the largest bay in Borneo – Darvel Bay, Malaysia. Accuracy assessment was carried out to evaluate the integrity of the reef habitat map of a tropical island (Baik Island), using test plot and point sampling method. Despite the unsatisfactory test plot method, we found that point sampling method yielded a better internal accuracy of 78%. We demonstrated that factors such as orientation to shore and water depth do not impose significant influence to the AGDS performance using U-Mann-Whitney tests and regression analysis. Overall, the resulting island's habitat map exhibits decent repeatability with map accuracy higher than 80%. The penultimate section of this manuscript also evaluates and provides beneficial information on the potential and strength of AGDS system and its inherent limitation in classifying benthic substrate to a preferred level of details based on the user requirement
Airway relaxation effects of water-soluble sclerotial extract from Lignosus rhinocerotis
No full textLignosus rhinocerotis has a long history of use by the indigenous community within East Asia to treat a range of health conditions including asthma and chronic cough. To date, there is limited scientific evidence to support its therapeutic effects in relieving these airways conditions. In this study, we examined the effects of the different molecular weight fractions [high-molecular-weight (HMW), medium-molecular-weight (MMW), and low-molecular-weight (LMW)] obtained from the cold water sclerotial extract (CWE) of L. rhinocerotis on airways patency using airway segments isolated from Sprague Dawley rat in an organ bath set-up. It is demonstrated that the HMW and MMW fractions exhibited higher efficacy in relaxing the pre-contracted airways when compared to the CWE and LMW fraction. In addition, the HMW fraction markedly supressed carbachol-, 5-hydroxytrptamine-, and calcium-induced airway contractions. CWE demonstrated a lower efficacy than the HMW fraction but it also significantly attenuated carbachol- and calcium-induced airway contractions. Results showed that the bronchorelaxation effect of CWE and fractions is mediated via blockade of extracellular Ca 2+ influx. The composition analysis revealed the following parts of carbohydrate and proteins, respectively: HMW fraction: 71 and 4%; MMW fraction: 35 and 1%; and LMW fraction: 22 and 0.3%. Our results strongly suggest that the polysaccharide-protein complex or proteins found in the HMW and MMW fractions is likely to contribute to the bronchorelaxation effect of CWE
Physico-thermal properties of kenaf fiber/high-density polyethylene/maleic anhydride compatibilized composites
No full textKenaf fiber/high-density polyethylene/maleic anhydride (MA)-compatibilized composites were melt mixed in a twin-screw extruder and molded using injection molding machine. Physicothermal properties of the composites were studied at different percentages of compatibilizer contents using various techniques. The addition of 8% compatibilizer into 8.5 and 17.5 wt% fiber content improved the adhesion and tensile strength by 14.5% and 13.6%, respectively. Compatibilized samples exhibited higher peak load and fracture energy on impact testing compared to the samples without maleic anhydride compatibilizer. The effect of the addition of maleic anhydride compatibilizer on peak load and fracture energy was observed to be at its highest at 8%. Differential scanning calorimetric measurements revealed that the melting enthalpy and degree of crystallinity of composites increased with increasing compatibilizer content up to 8% and then decreased at 12% compatibilizer content. Dynamic mechanical analysis showed that the storage modulus of composites was increased, but the loss modulus and tangent delta were decreased after the addition of compatibilizer. This indicates that compatibilized composites produced have improved toughness and reduced stiffness
Beta Adrenergic Receptors Stimulation Attenuates Phosphorylation of NF-κB and IκBα in Hyperglycemic Endothelial Cells
No full textBackground/Aims: NF-κB induces transcription of a number of genes, associated with inflammation and apoptosis. In this study, we have investigated the effect of β-adrenergic receptor stimulation on NF-κB and IκBα in HUVECs. Methods: Human umbilical vein endothelial cells (HUVECs) were cultured in high and low glucose concentrations. All HUVECs were treated with different concentrations of isoproterenol and propranolol for different time periods. The analytical procedures consisted of Western Blot, ELISA, DCFH-DA and TUNEL assays. Results: Isoproterenol (agonist of a beta-adrenergic receptor) significantly reduced phosphorylation at Ser-536 of NF-κB; and Ser-32 and Ser-36 of IκBα in hyperglycemic HUVECs. Isoproterenol also significantly reduced apoptosis and ROS generation. No effect of IκBα was observed on Tyr-42 phosphorylation. The effect of isoproterenol was reversed by the antagonist propranolol. We also checked if NF-κB inhibitor MG132 causes any change at the level of apoptosis. However, we observed an almost similar effect. Conclusion: Given data demonstrates that beta-adrenergic receptors stimulation has a protective effect on HUVECs that might be occuring via NF-κβ and IκBα pathway
A New Discordancy Test on a Regression for Cylindrical Data
No full textA cylindrical data set consists of circular and linear variables. We focus on developing an outlier detection procedure for cylindrical regression model proposed by Johnson and Wehrly (1978) based on the k-nearest neighbour approach. The procedure is applied based on the residuals where the distance between two residuals is measured by the Euclidean distance. This procedure can be used to detect single or multiple outliers. Cut-off points of the test statistic are generated and its performance is then evaluated via simulation. For illustration, we apply the test on the wind data set obtained from the Malaysian Meteorological Department
The economic cost of the Islamic State on the Syrian and Iraqi economies
No full textIn this paper, we evaluate the economic cost of the Islamic State on the Syrian and Iraqi economies from 2010 to 2016. To do so, we use the Post-Terrorism Final Economic Damage Simulator—PTFED-Simulator. The PTFED-Simulator assesses the economic damage of terrorism based on ten different indicators: (1) total regional terrorism tension (∆Tt); (2) harmonized anti-terrorist strategy (AT+); (3) war losses from terrorism (−πt); (4) total economic leakage from terrorism (−Ψt); (5) economic desgrowth from terrorism (−δt); (6) military dimension of terrorism (MDt); (7) post-terrorism economic damage (−Πt); (8) post terrorism economic damage evaluation; (9) post-terrorism reconstruction plan (PTRt); and (10) terrorism effect on mega-disk networks mapping. Overall, we seek to evaluate the impact of terrorism on economic performance from a multi-dimensional perspective in both the short run and long run
Biodegradation of Crystal Violet dye by bacteria isolated from textile industry effluents
No full textIndustrial effluent containing textile dyes is regarded as a major environmental concern in the present world. Crystal Violet is one of the vital textile dyes of the triphenylmethane group; it is widely used in textile industry and known for its mutagenic and mitotic poisoning nature. Bioremediation, especially through bacteria, is becoming an emerging and important sector in effluent treatment. This study aimed to isolate and identify Crystal Violet degrading bacteria from industrial effluents with potential use in bioremediation. The decolorizing activity of the bacteria was measured using a photo electric colorimeter after aerobic incubation in different time intervals of the isolates. Environmental parameters such as pH, temperature, initial dye concentration and inoculum size were optimized using mineral salt medium containing different concentration of Crystal Violet dye. Complete decolorizing efficiency was observed in a mineral salt medium containing up to 150 mg/l of Crystal Violet dye by 10% (v/v) inoculums of Enterobacter sp. CV-S1 tested under 72 h of shaking incubation at temperature 35 °C and pH 6.5. Newly identified bacteria Enterobacter sp. CV-S1, confirmed by 16S ribosomal RNA sequencing, was found as a potential bioremediation biocatalyst in the aerobic degradation/de-colorization of Crystal Violet dye. The efficiency of degrading triphenylmethane dye by this isolate, minus the supply of extra carbon or nitrogen sources in the media, highlights the significance of larger- scale treatment of textile effluent
Q-switched erbium-doped fiber laser using thulium fiber saturable absorber
No full textWe demonstrated a passive Q-switched Erbium-doped fiber laser (EDFL) based on Thulium fiber saturable absorber (SA). The EDFL generates a Q-switching pulse operating at 1564 nm as the pump power is increased above the threshold pump power of 66 mW. The Q-switching operation is maintained before disappearance when the pump power is above 104 mW. This is due to the fact that the thulium fiber could not fully recover in time after a pulse and less gain populations is excited before the next pulsing. With the SA, the laser produces a stable pulse train with repetition rate ranging from 2.18 to 3.16 kHz and the pulse width reduces from 127.4 to 75.4 µs while varying the pump power from 66 mW to 104 mW. The maximum pulse energy of 8.2 nJ is obtained at a pump power of 104 mW. The advantages of the fiber based saturable-absorbers are their ability to hold enormous gain excited in the gain fiber from lasing and their high damage threshold for high-power Q-switched pulses
Early AbobotulinumtoxinA (Dysport®) in Post-Stroke Adult Upper Limb Spasticity: ONTIME Pilot Study
No full textThe ONTIME study investigated whether early post-stroke abobotulinumtoxinA injection delays appearance or progression of upper limb spasticity (ULS) symptoms. ONTIME (NCT02321436) was a 28-week, exploratory, double-blind, randomized, placebo-controlled study of abobotulinumtoxinA 500U in patients with ULS (Modified Ashworth Scale [MAS] score ≥ 2) 2–12 weeks post-stroke. Patients were either symptomatic or asymptomatic (only increased MAS) at baseline. Primary efficacy outcome measure: time between injection and visit at which re-injection criteria were met (MAS ≥ 2 and ≥1, sign of symptomatic spasticity: pain, involuntary movements, impaired active or passive function). Forty-two patients were randomized (abobotulinumtoxinA 500U: n = 28; placebo: n = 14) with median 5.86 weeks since stroke. Median time to reach re-injection criteria was significantly longer for abobotulinumtoxinA (156 days) than placebo (32 days; log-rank: p = 0.0176; Wilcoxon: p = 0.0480). Eleven (39.3%) patients receiving abobotulinumtoxinA did not require re-injection for ≥28 weeks versus two (14.3%) in placebo group. In this exploratory study, early abobotulinumtoxinA treatment significantly delayed time to reach re-injection criteria compared with placebo in patients with post-stroke ULS. These findings suggest an optimal time for post-stroke spasticity management and help determine the design and sample sizes for larger confirmatory studies
The Clinimetric Properties of Instruments Measuring Home Hazards for Older People at Risk of Falling: A Systematic Review
No full textHome hazards are associated with falls among older people living in the community. However, evaluating home hazards is a complex process as environmental factors vary according to geography, culture, and architectural design. As a result, many health practitioners commonly use nonstandardized assessment methods that may lead to inaccurate findings. Thus, the aim of this systematic review was to identify standardized instruments for evaluating home hazards related to falls and evaluate the clinimetric properties of these instruments for use by health practitioners. A systematic search was conducted in the Medline, CINAHL, AgeLine, Web of Science databases, and the University of Sydney Library CrossSearch Engine. Study screening, assessment, and quality ratings were conducted independently. Thirty-six studies were identified describing 19 instruments and three assessment techniques. The clinimetric properties varied between instruments. The Home Falls and Accidents Screening Tool, Home Safety Self-Assessment Tool, In-Home Occupational Performance Evaluation, and Westmead Home Safety Assessment were the instruments with high potential for evaluating home hazards associated with falls. Health practitioners can choose the most appropriate instruments for their practice, as a range of standardized instruments with established clinimetric properties are available