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Microstructural evolution and micromechanical properties of thermally sprayed hydroxyapatite coating
No full textThe effects of preheating and annealing processes on the micromechanical features of thermally sprayed hydroxyapatite (HA) coatings were investigated. The results indicated that subsequent heat treatment at 700°C for 60 min promotes the development of a crystalline HA coating. The EDS line scan showed that the oxygen content was homogeneous along the thickness direction from the coating surface to the titanium–HA interface, whereas the calcium and phosphorus concentration gradually decreased at 7 μm from the interface. From the roughness profiles, the coatings on preheated substrates gave lower roughness compared to the coatings at room temperature. According to the nanoindentation results, the sample preheated at 300°C after annealing at 700°C exhibited an elastic modulus of 108.1 ± 6 GPa and hardness of 5.97 ± 0.3 GPa, which were almost 3% lower and 171% higher than the bare substrate, respectively
Media Attention for Climate Change Mitigation and Adaptation in Malaysia: A Comparative Analysis of Malaysia Chinese Newspaper Coverage
No full textClimate change is a global problem and it is more likely caused by human activities and human greed. Studies on media representations of climate change by far are less potent on Asia country compared with Western societies. Climate change is one of the crucial issues and the media has been established to play an essential key role in constructing public awareness and policy adaptation. The research aims to examine and compare Malaysia's Chinese newspapers' portrayal on climate change mitigation and adaption from January 2015 to December 2015. Agenda setting theory is used to guide this study. Two major Chinese newspapers in Malaysia which are Sin Chew Daily and China Press were chosen as content analysis materials as both newspapers have the highest readership and circulation compare with others Chinese newspaper. Through the analysis of Malaysia major Chinese newspaper, both newspapers have a different level of media attention on climate change mitigation and adaptation issue. The media attention includes news monthly distribution, news focus, news perception, news genre and domesticity. Both newspapers mentioned above represented a unique way of reporting climate change issue. The greater of media attention on climate change issue can provide a wider exposure with the community
Tunable Q-switched erbium-doped fiber laser using nickel oxide saturable absorber
No full textWe fabricated a Nickel oxide (NiO) polymer composite saturable absorber, and used it to passively generated Q-switch Erbium-doped fiber laser (EDFL). It was tunable from 1535 to 1565 nm. At operating wavelength of 1535 nm, the repetition rate of the self-starting Q-switching pulses could be increased from 17.9 kHz to 28.2 kHz while the pulse width reduced from 16.1 to 9.1 μs with increasing pump power from 14.9 to 37.7 mW. The highest slope efficiency of 22.11% was obtained at operating wavelength of 1540 nm. The output pulse energy increased from 139 nJ to 419 nJ as the pump power varied from 4.9 to 37.7 mW at the operating wavelength of 1565 nm. This saturable absorber forms a simple and cost-effective light source for environmental sensing, metrology and biomedical diagnostics
Non-dominated sorting biogeography-based optimization for bi-objective reentrant flexible manufacturing system scheduling
No full textScheduling in flexible manufacturing systems (FMS) is described as an NP-Hard problem. Its complexity has increased significantly in line with the development of FMS over the past years. This paper presents a non-dominated sorting biogeography-based optimization (NSBBO) for scheduling problem of FMS having multi loading-unloading and shortcuts infused in the reentrant characteristics. This model is formulated to identify the near optimal trade-off solutions capable of addressing the bi-objectives of minimization of makespan and total earliness. The goal is to simultaneously determine the best machine assignment and job sequencing to satisfy both objectives. We propose the development of NSBBO by substituting the standard linear function of emigration-immigration rate with three approaches based on sinusoidal, quadratic and trapezoidal models. A selection of test problems was examined to analyze the effectiveness, efficiency and diversity levels of the proposed approaches as compared to standard NSBBO and NSGA-II. The results have shown that the NSBBO-trapezoidal model performed favorably and is comparable to current existing models. We conclude that the developed NSBBO and its variants are suitable alternative methods to achieve the bi-objective satisfaction of reentrant FMS scheduling problem
People with disabilities: An ancient society got it right, but can we?
Get PDFPersons with disabilities of today often have difficulty reaching full career and social status, due to physical, functional, practical and psychological factors. The Lenggong Valley, in the state of Perak, Malaysia contains the 11,000 year old remains of a member of the Austramelenesoid family. He was tall, but had several abnormalities. He had a skeletal deformity of the upper limb. His elbow was held flexed, wrist extended and he had an abnormal left middle finger. He also had a scoliosis and a shorter left lower limb. It is estimated that he walked with a limp. However he is estimated to have died at the age of 40 to 45 years, twice the life expectancy of his time. Archeological findings indicated that he was buried as an important person in the tribe, possibly a Shaman. With his abnormalities, he was probably unable to hunt effectively, yet obviously given a more appropriate role to play and able to lead a long life of a respected person, being buried with full honours of his time. An ancient civilization was able to adapt roles so that a person with disabilities could use his unique abilities to contribute to society and lead a respected life, something present society could think about and learn from. If current society could help the disabled to achieve their full potential everyone would stand to benefit
Ultrasmall superparamagnetic Fe3O4 nanoparticles: honey-based green and facile synthesis and in vitro viability assay
No full textIntroduction: In the present research, we report a quick and green synthesis of magnetite nanoparticles (Fe 3 O 4 -NPs) in aqueous solution using ferric and ferrous chloride, with different percentages of natural honey (0.5%, 1.0%, 3.0% and 5.0% w/v) as the precursors, stabilizer, reducing and capping agent, respectively. The effect of the stabilizer on the magnetic properties and size of Fe 3 O 4 -NPs was also studied. Methods: The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy. Results: The XRD analysis indicated the presence of pure Fe 3 O 4 -NPs while the TEM images indicated that the Fe 3 O 4 -NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM study demonstrated that the magnetic properties were enhanced with the decrease in the percentage of honey. In vitro viability evaluation of Fe 3 O 4 -NPs performed by using the MTT assay on the WEHI164 cells demonstrated no significant toxicity in higher concentration up to 140.0 ppm, which allows them to be used in some biological applications such as drug delivery. Conclusion: The presented synthesis method can be used for the controlled synthesis of Fe 3 O 4 -NPs, which could be found to be important in applications in biotechnology, biosensor and biomedicine, magnetic resonance imaging and catalysis
Climate change mitigation projections for ASEAN
No full textThis article analyses climate mitigation impact once the Association of Southeast Asian Nations (ASEAN) introduce their respective Intended Nationally Determined Contribution (INDC) using dynamic non-linear computable general equilibrium modelling and 2010 input-output tables. The results indicate that atmospheric concentration of carbon and temperatures under the business as usual (BAU) scenario will fall from 390 PPM and 0.80°C respectively in 2010 to 351PPM and 0.79°C respectively, whereas under the optimal scenario it will fall to 329PPM and 0.71°C respectively in 2060. Cumulative climate damage under BAU and optimal scenarios will remain the same at MYR8.0 Billion, MYR14.3 Billion and MYR 24.8 Billion respectively in 2010, 2015 and 2020 but it will rise after that to MYR579 Billion under the former compared to MYR513 Billion under the latter in 2060. The reduction in carbon emissions shall also be achieved without a tangible fall in GDP per capita
Beyond HbA1c: Comparing Glycemic Variability and Glycemic Indices in Predicting Hypoglycemia in Type 1 and Type 2 Diabetes
No full textBackground: Hypoglycemia is the major impediment to therapy intensification in diabetes. Although higher individualized HbA1c targets are perceived to reduce the risk of hypoglycemia in those at risk of hypoglycemia, HbA1c itself is a poor predictor of hypoglycemia. We assessed the use of glycemic variability (GV) and glycemic indices as independent predictors of hypoglycemia. Methods: A retrospective observational study of 60 type 1 and 100 type 2 diabetes subjects. All underwent professional continuous glucose monitoring (CGM) for 3-6 days and recorded self-monitored blood glucose (SMBG). Indices were calculated from both CGM and SMBG. Statistical analyses included regression and area under receiver operator curve (AUC) analyses. Results: Hypoglycemia frequency (53.3% vs. 24%, P < 0.05) and %CV (40.1% ± 10% vs. 29.4% ± 7.8%, P < 0.001) were significantly higher in type 1 diabetes compared with type 2 diabetes. HbA1c was, at best, a weak predictor of hypoglycemia. %CVCGM, Low Blood Glucose Index (LBGI)CGM, Glycemic Risk Assessment Diabetes Equation (GRADE)HypoglycemiaCGM, and Hypoglycemia IndexCGM predicted hypoglycemia well. %CVCGM and %CVSMBG consistently remained a robust discriminator of hypoglycemia in type 1 diabetes (AUC 0.88). In type 2 diabetes, a combination of HbA1c and %CVSMBG or LBGISMBG could help discriminate hypoglycemia. Conclusion: Assessment of glycemia should go beyond HbA1c and incorporate measures of GV and glycemic indices. %CVSMBG in type 1 diabetes and LBGISMBG or a combination of HbA1c and %CVSMBG in type 2 diabetes discriminated hypoglycemia well. In defining hypoglycemia risk using GV and glycemic indices, diabetes subtypes and data source (CGM vs. SMBG) must be considered
Exacerbated symptoms in Blastocystis sp.-infected patients treated with metronidazole: two case studies
No full textBlastocystis sp. is a gastrointestinal (GI) protozoan parasite reported to cause non-specific GI symptoms including diarrhea, flatulence, abdominal pain, and nausea. Complete eradication of Blastocystis sp. is rather challenging even with the drug of choice, i.e., metronidazole. Here, we report on two Blastocystis sp.-infected individuals, who presented increased parasite load and exacerbated symptoms upon treatment with the usual recommended dosage and regime of metronidazole. The two studies uniquely demonstrate for the first time a cyst count as high as fivefold more than the original cyst count before treatment and show an exacerbation of GI symptoms despite treatment. The study provides additional support in recognizing metronidazole resistance in Blastocystis sp. and its consequences towards the pathogenicity of the parasite
Physical Characterization of a Deep Weathering Profile Over Rhyolite in Humid Tropical Peninsular Malaysia
No full textThe weathering profile, exposed at 38.2 km of the Kuala Lumpur—Karak Highway, can be differentiated into three broad zones; the topmost Zone I (pedological soil) comprising A, B and C soil horizons and made up of clayey silty sand with indistinct relict bedrock textures. The intermediate Zone II (saprock) consists of gravelly silty sand with distinct relict bedrock texture and structures, and can be sub-divided based on differences in volumes of litho-relicts. The bottom Zone III (bedrock) is a continuous outcrop of rhyolite with alteration along discontinuity planes; its upper surface marked by an unconfined groundwater table. The weathering zones thin towards valley sides and can be assigned rock mass weathering grades; Zones I and II defining the residual soil over bedrock. Constant volume samples in Zone II show an upward decrease in dry unit weights, porosities and silt contents, but a corresponding increase in clay contents. Constant volume samples in Zone I show it to be distinct from Zone II with large clay contents but low porosities and silt contents. Decreasing fine clay contents with depth and stained quartz grains show pedological processes to have given rise to Zone I. As the silt-sized (sericite) particles mainly originate from alteration of bedrock feldspars and later break-down to clay-sized (illite and kaolinite) particles, a textural weathering index (Iw) based on the ratio of clay to silt and clay contents, is proposed to describe the progress of weathering within the profile. It is concluded that the saprock results from in situ alteration of the rhyolite rock mass due to lowering of an unconfined groundwater table whilst the A, B and C soil horizons have formed by pedological processes acting on saprock