This is a brief report of 4 paediatric cases of COVID-19 infection in Malaysia
COVID-19, a coronavirus, first detected in Wuhan, China has now spread rapidly to over 60 countries and territories ...around the world, infecting more than 85000 individuals. As the case count amongst children is low, there is need to report COVID-19 in children to better understand the virus and the disease.
In Malaysia, until end of February 2020, there were four COVID-19 paediatric cases with ages ranging from 20 months to 11 years. All four cases were likely to have contracted the virus in China. The children had no symptoms or mild flu-like illness. The cases were managed symptomatically. None required antiviral therapy.
There were 2 major issues regarding the care of infected children. Firstly, the quarantine of an infected child with a parent who tested negative was an ethical dilemma. Secondly, oropharyngeal and nasal swabs in children were at risk of false negative results. These issues have implications for infection control. Consequently, there is a need for clearer guidelines for child quarantine and testing methods in the management of COVID-19 in children.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Crimean-Congo haemorrhagic fever virus (CCHFV) is a tick-borne virus causing Crimean-Congo haemorrhagic fever (CCHF), a disease reported to have a high fatality rate in numerous countries. The virus ...is geographically widespread due to its vector, and numerous wild and domestic animals can develop asymptomatic infection. Serological and limited molecular evidence of CCHFV has previously been reported in
(the dromedary, or one-humped camel) in the United Arab Emirates (UAE). In this study, 238 camel samples were screened for CCHFV RNA where 16 camel samples were positive for CCHFV by RT-PCR. Analysis of full-length CCHFV genome sequences revealed a novel lineage in camels from the UAE, and potential reassortment of the M segment of the genome.
Cerium substituted yttrium iron garnet films with a chemical formula Y3−xCexFe5O12 (x=0.0–0.3) have been successfully prepared by a sol–gel method. The microstructure analysis showed that all films ...exist in the cubic garnet structure. The lattice parameter and grain size increased with the increment of Ce concentrations up to 0.25, indicating the complete Ce substitution in yttrium site. For a film with x=0.3, the lattice parameter remained unchanged and grain size decreased. The film thickness increased and surface roughness varied with the increment of Ce content. All of the films have high optical transparency (above 80%). The Ce content reduced the saturation magnetization of the film up to a certain limit where above this limit the value increased. Overall, the findings showed that the films with x≤0.25 exhibited very excellent properties, hence they are promising materials for magneto-optical devices.
•The maximum substitution of Ce3+ ions in the CexY3−xFe5O12 sol-gel film was x = 0.25.•The Ce content reduced the saturation magnetization (Ms) of the film at a certain x value then the Ms increased.•The coercivity values of films indicate there are multi domain and single domain film.•The films with x≤0.25 are suitable to be applied in magneto-optical devices.
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•Thirty-five novel triazine-based compounds were designed and synthesized as colchicine binding site inhibitors.•Cytotoxicity was determined against MCF-7, HepG-2, and HCT-116 cell ...lines.•Tubulin polymerization inhibitory activities and apoptotic potential were evaluated.•In Silico studies and an evaluation of drug-likeness properties were carried out.
Thirty-five new colchicine binding site inhibitors have been designed and synthesized based on the 1,2,4-triazin-3(2H)-one nucleus. Such molecules were synthesized through a cascade reaction between readily accessible α-amino ketones and phenyl carbazate as a masked N-isocyanate precursor. The synthesized derivatives are cisoid restricted combretastatin A4 analogues containing 1,2,4-triazin-3(2H)-one in place of the olefinic bond, and they have the same essential pharmacophoric features of colchicine binding site inhibitors. The synthesized compounds were evaluated in vitro for their antiproliferative activities against a panel of three human cancer cell lines (MCF-7, HepG-2, and HCT-116), using colchicine as a positive control. Among them, two compounds 5i and 6i demonstrated a significant antiproliferative effect against all cell lines with IC50 ranging from 8.2 − 18.2 µM. Further investigation was carried out for the most active cytotoxic agents as tubulin polymerization inhibitors. Compounds 5i and 6i effectively inhibited microtubule assembly with IC50 values ranging from 3.9 to 7.8 µM. Tubulin polymerization assay results were found to be comparable with the cytotoxicity results. The cell cycle analysis revealed significant G2/M cell cycle arrest of the analogue 5i in HepG-2 cells. The most active compounds 4i, 4j, 5 g, 5i and 6i did not induce significant cell death in normal human lung cells Wl-38, suggesting their selectivity against cancer cells. Also, These compounds upregulated the level of active caspase-3 and boosted the levels of the pro-apoptotic protein Bax by five to seven folds in comparison to the control. Moreover, apoptosis analyses were conducted for compound 5i to evaluate its apoptotic potential. Finally, in silico studies were conducted to reveal the probable interaction with the colchicine binding site. ADME prediction study of the designed compounds showed that they are not only with promising tubulin polymerization inhibitory activity but also with favorable pharmacokinetic and drug-likeness properties.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•YIG films with grain size <12 nm were prepared by a sol-gel method.•The saturation magnetization decreases with increasing temperature from 10 to 300 K.•The coercivity decreases with increasing ...temperatures from 10 to 300 K.•The Curie temperature is in the range of 554 to 601 K.
We report on YIG film with small grain size (<12 nm) that has the potential to be used in microwave device application. The nanostructured film has been deposited on quartz substrate by a sol-gel spin coating technique, followed by annealing at temperatures in the range between 700 and 900 °C. The structural and magnetic properties of the film in the range 10–610 K were investigated. The X-ray diffraction results demonstrate that the films formed in a polycrystalline structure with lattice parameter in the range of 12.249–12.359 Å, lower than that of bulk materials. The saturation magnetization decreased not linearly with increasing the temperature from 10 to 300 K, differently from that reported for the bulk YIG. The coercivity value decreased with increasing temperatures (10–300 K), except for the film annealed at 800 °C. The Curie temperature of the film annealed at 700 °C was 554 K, however, other films showed higher Curie temperature values than that reported for bulk YIG. These properties are strongly influenced by the stress in the film’s structure due to the different thermal expansion coefficient of the YIG and the quartz substrate.
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Cerium substitute Y2.8−xDy0.2CexFe5O12 (x=0, 0.2, 0.25, 0.3, 0.35) films have been prepared on quartz substrates by a simple sol–gel method and followed by a spin-coating technique. The crystalline ...structures, surface and magnetic properties of the films has been investigated by an X-ray diffractometer (XRD), a field emission scanning electron microscope (FESEM), an atomic force microscope (AFM) and a vibrating sample magnetometer (VSM). The XRD analysis revealed that the films have garnet structure. The lattice parameter increased as Ce content was increased up to 0.25 due to the Ce3+ ions completely substituted for Y3+ ions. For films x≥0.3, the lattice parameter decreased. The FESEM results showed that the average grains were small, ranging from 11 to 14nm and the thickness of films increased with the increment of Ce contents. VSM results for both in and out-plane magnetic measurement showed the film with x=0 has the highest saturation magnetization (Ms) values. With the increment of Ce contents, the Ms of films decreased due to the substitution of Ce3+, Dy3+ ions in the c-site. For films x≥0.3 the reduction of Ms values was due to the presence of CeO2 in the film. The films with x=0–0.25 exhibited increases in Hc values. The improvement of coercivity value, small grain size and high crystalline structure of film with x=0.25 has a potential to be used in magneto optical (MO) memory storage applications.
•Ce-doped Y2.8−xDy0.2CexFe5O12 films were prepared by the sol–gel method.•The solubility limit of Ce3+ ions in the film was x=0.25.•The average grain size ranging from 11 to 14nm with the increment of Ce doping.•Increasing Ce contents degrades the saturation of magnetization of films.•Increasing Ce contents improve the coercivity of films.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A method based on micellar liquid chromatography to quantify levodopa, carbidopa and entacapone in plasma is reported. The sample pretreatment was a simple dilution in a pure micellar solution then ...filtration and direct injection, without requiring extraction or purification steps. The three drugs were resolved from the matrix in 7 min, using an aqueous solution of 0.1 M sodium dodecyl sulphate-10% n-propanol-0.3 tiethylamine, adjusted at pH 2.8 with 0.02 M orthophosphoric acid as mobile phase, running under isocratic mode at 1.0 mL/ min through VP-ODS column. The detection was done by UV (ultraviolet) absorbance at 225 nm. The method was successfully validated by the International Conference Harmonization guidelines in terms of: selectivity, linearity (r2 > 0.998) over the concentration ranges of 0.025–1.2, 0.05–1.0 and 0.3–2.0 μg mL−1 with limits of detection of 0.01, 6.16 × 10−3 and 0.02 μg mL−1 and limits of quantification of 0.03, 0.02 and 0.07 μg mL−1 for levodopa, carbidopa and entacapone, respectively. The proposed method was applied successfully for quantification of the studied drugs in their different dosage forms. Moreover, the method was further extensive to the quantification of the studied drugs in spiked human plasma and was successfully validated by the guidelines of the European Medicines Agency. The proposed procedures were successfully evaluated to determine the studied drugs in real human plasma. The procedure was found reliable, practical, cost-effective, available, short period, easy-to-handle, low-cost, environmental-friendly, secure, useful for the analysis of numerous samples per day. Lastly, the method was performed to the analysis of incurred, using quality control samples in the same analytical run, with adequate results. Therefore, it can be implementable for custom analysis in clinical laboratories.
•This is the first method on micellar liquid chromatographic method for the simultaneous determination of levodopa, carbidopa and entacapone in their pharmaceutical preparations.•Micellar liquid chromatographic is one mode of green analytical chemistry, where it reduces analysis costs and avoids the analytical methodologies hazards.•The high sensitivity of the proposed method allowed the determination of levodopa and carbidopa or levodopa, carbidopa and entacapone in spiked human plasma and real human plasma, and to study its pharmacokinetics.
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•The experimental test rig is developed utilising the FPLG principle of a dual-piston air-driven system.•Effects of FPLG aspect ratio on the power generation are investigated.•Effects of FPLG aspect ...ratio on combustion efficiency and energy density are discussed.•Effects of equivalence ratio on the FPLG aspect ratio stability and conversion efficiency are identified.
The thermal efficiency (40–50%) of free-piston linear generator (FPLG) engines is widely known to be higher than the conventional reciprocating engine (CRE) (30–40%). Future technology to optimise FPLG engine combustion necessitates the identification of a stroke to bore ratio (Aspect Ratio, AR). This paper presents a report on the effects of different aspect ratios (1, 1.5, and 2) on the FPLG operating frequency and power output. The development of an experimental test rig was through the utilisation of the FPLG principle of a dual-piston (bounce and combustion chamber) air-driven system. The mechanical function of the FPLG is converted into electric power through the linear generator. The piston velocity, power output (Prms), operating frequency, as well as system energy density and conversion efficiency are discussed in the paper. The FPLG operation using long-stroke (AR2) shows obvious advantages in the peak velocity and Prms; however, the operating frequency is higher in the short stroke, although the in-cylinder pressure, compression ratio, and piston velocity are slightly lower. The calculated energy density indicates the medium stroke (AR1.5) is the optimum in the operating frequency and Prms for overall FPLG operation; besides, it works perfectly in a lean condition. The shortest stroke has better combustion efficiency (38.5%) at the stoichiometric condition; however, this percentage significantly increased in a lean condition (ER = 0.4) for AR1.5 and AR2 to 55.67% and 62.39%, respectively, with an increment of 49.3% and 46.6%. The system conversion efficiency decreases with the increase of the aspect ratio.
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•Simultaneous dearomatization of four impurities using a salt-acid-based eutectic solvent.•The solvent was characterized by its eutectic point, physical, and critical ...properties.•Phase behavior was determined experimentally, predicted via COSMO-RS, and correlated via NRTL.•Molecular-level interactions and mechanisms of extraction were studied.•Parametric investigation of the multicomponent extraction process was conducted.
Eutectic solvents (ESs) have been extensively studied in the literature for the purification of fuels. Nevertheless, most studies investigated the extraction of a single type of aromatic from n-alkanes. In this work, aiming to provide insights about the performance of ESs in a process that mimics the multicomponent dearomatization used industrially, a salt-acid-based ES, comprised of methyltriphenyl-phosphonium bromide and acetic acid, was applied in simultaneously extracting toluene, thiophene, quinoline, and pyrrole from n-decane. First, the DES was characterized for its eutectic composition, physicochemical, and critical properties. Then, an initial screening to determine the molecular-level interactions and extraction mechanism were studied experimentally and using COSMO-RS screening charge density profiles and potentials. A physical mechanism was confirmed for the extraction of pyrrole, thiophene, and toluene while for quinoline, an acid-base reaction was the predominant extraction mechanism. The phase diagrams of each impurity were also experimentally determined, predicted using the COSMO-RS model, and correlated using the NRTL model in Aspen Plus. Lastly, a parametric investigation studying the impact of key parameters including stirring time, initial concentration, mixing effects, solvent-to-feed ratio, multi-stage extraction, and repetitive usage of solvent was conducted. On multi-stage extraction, full recovery of pyrrole and quinoline (≈99.9%) was achieved in only 2-stages, whereas for thiophene and toluene efficiencies of 82.2% and 58.4% were reached after the 5th stage, respectively.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This paper proposed and implemented an energy-aware routing multi-level and mapping problem (EARMLP) algorithm to minimize the overall power consumption in Software-Defined Networking (SDN)-based ...core networks. To enforce network utilization toward green policies design for Data Centers (DCs), SDN leverages protocol configurations for routing available in the infrastructure. Therefore, the proposed mechanism aimed to design an optimal routing strategy that considers system configuration and traffic demand between the data and control planes in networks. The problem is then addressed from the perspective of the policy-based EARMLP technique, which is used to carefully determine the optimal assignment between controllers and their switches to optimize network energy savings. Hence, a controller placement problem (CPP) is established to select the optimal locations and number of controllers in core networks and create an optimal mapping and resource allocation between switches and controllers. Since the formulated energy-aware routing algorithm is designed as a multi-objective NP-hardness of the problem, a heuristic approach is developed to find optimal solutions for traffic routing between inter-controllers and controller-switch in terms of energy-aware consumption strategies. Consequently, the proposed optimal routing mechanism can rearrange traffic to meet provisioning criteria by utilizing the capacity-aware design. Remarkably, the energy saved in networks by our suggested method can approach up to 70% of the energy saved in SDN-based networks compared to other methods.
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