19672 research outputs found
Sort by
Age at menarche and sexual debut among young Filipino women
No full textThere has been a secular decline in age at menarche since the 19th century. Early-maturing women are more likely to have their sexual debut at a younger age, which in turn gives rise to a host of reproductive health and social problems. This study used data from five waves of National Demographic and Health Surveys conducted in the Philippines between 1993 and 2013 to examine the trends and socioeconomic differentials in age at menarche and sexual debut. The changing trend in age at menarche and sexual debut was examined across birth cohorts, and logistic regressions were used to identify the determinants of early sexual debut. In the Philippines, the mean and median ages at menarche declined from 13.2 years and 12.6 years, respectively, among young women born in 1973–1977, to 12.9 years and 12.3 years, respectively, among those born in 1993–1997. The proportion who had their sexual debut by age 20 increased from 41.2% for the 1968–1972 birth cohort to 53.4% for the 1988–1992 birth cohort. Filipino women with low education, from poor families and living in rural areas were more likely to have earlier sexual debut despite attaining menarche at a later age as compared with their higher educated counterparts, and those from wealthier families and urban areas. Logistic regression analysis showed that, besides marital status, women’s education and age at menarche were important determinants of early sexual debut. However, ethnicity, place of residence and family wealth had no significant effects on age at menarche. An increasing proportion of young women were found to be having unprotected sexual debut and at a younger age, with health and social ramifications. Hence, apart from increasing the enrolment of girls in schools and discouraging teenage marriage, there is a need for social and health agencies to implement appropriate adolescent sexual and reproductive health programmes such as counselling and educational campaigns, as well as support services, to address sexual problems among the youth
Slope monitoring: an application of time-lapse electrical resistivity imaging method in Bukit Antarabangsa, Kuala Lumpur
No full textSlope monitoring study using 2-D electrical resistivity imaging method was conducted on a slope where a massive landslide occurred in December 2008 in Bukit Antarabangsa, Kuala Lumpur, Malaysia. The main objective of the study is to determine the subsurface resistivity distribution of the study area and to map the risk/potential zone of landslide in the future. To detect the changes in the subsurface resistivity distribution due to variation in water saturation in the subsurface, time-lapse electrical resistivity imaging method was applied in this study. Repeated measurements of electrical resistivity over chosen lines at different times were done to monitor the changes in the subsurface resistivity distribution. The results obtained from the time-lapse electrical resistivity shows that there are significant changes in the subsurface resistivity distribution during different periods. Locations of possible slope failure are identified along the slope and are divided into Zone 1 and Zone 2. Weak zones are characterized by the large proportion of high water saturation zones and low resistivity values which are highly affected by the supply of water into the subsurface as well as the properties of the subsurface materials. These particular regions are more susceptible towards slope failure as high water content will ease the movement of soil in the subsurface. Thus, proper mitigation must be done at the problematic zones to prevent the occurrence of slope failure in the future
Instructional leadership in Malaysia: a review of the contemporary literature
No full textThis article provides a review of the contemporary instructional leadership research base in Malaysia. The core aim of this review is to assess the recent knowledge base on instructional leadership in Malaysia and to evaluate its current contribution to the existing international literature. The article explores a range of published material that has focused explicitly on instructional leadership and instructional leadership practices in Malaysia, including that written in Bahasa Malaysia. The article outlines the findings from the review and highlights certain strengths and limitations. The article concludes by identifying areas for further enquiry and investigation
Highly sensitive micro-hygrometer based on microfiber knot resonator
No full textIn this work, we experimentally demonstrated a microfiber knot resonator (MKR) for ambient relative humidity (RH) measurement. The microfiber device was manufactured by forming a ring from a low-loss microfiber, fabricated from a single-mode fiber (SMF) by using flame-heating technique. The resonator was successfully formed when a periodic output resonance spectrum was achieved. Without employing any coating hygroscopic material, the MKR was observed to highly sensitive to the variation of ambient RH ranging from of 30% RH to 94% RH. The proposed device is an extremely compact and fast response sensor, useful for a wide spectrum of industrial applications
Floristic and climatic changes at the Balingian Province of the Sarawak Basin, Malaysia, in response to Neogene global cooling, aridification and grassland expansion
No full textThe floristic and climatic changes at the onshore part of the Balingian Province of the Sarawak Basin in response to Neogene global cooling, aridification and grassland expansion were reconstructed in this study. We carried out palynological and petrographical studies on coal samples collected from the Early Pliocene Begrih Formation and the Late Pliocene Liang Formation. We compared these results with the available floristic and climatic data of the Early Miocene Balingian Formation to explore possible changes in vegetation and climate. The study results suggested that though there was increased seasonality or reduced rainfall as a result of Neogene global cooling and aridification, the onshore part of the Balingian Province had experienced everwet climates, and the flora in this region had changed from predominantly Kerangas forest during the Early Miocene to the species-rich peat swamp forest during the Early and Late Pliocene
Conceptualising consumer-based service brand equity (CBSBE) and direct service experience in the airline sector
No full textThe intense competition taking place in the airline sector requires a concurrently suitable branding strategy. Although contemporary brand equity models have been acknowledged and tested in the service branding context, they are not quite adaptable to the airline sector. These models are more appropriate for product-dominant brands, as they ignore the crucial roles of direct service experience and brand consistency in creating airline brand equity. Therefore, through a systematic and critical review of the literature, we propose a conceptualisation of consumer-based service brand equity (CBSBE) model by emphasising the importance of direct service experience and brand consistency that will equip airline marketing/brand managers to design effective branding strategies
Empirical study on temporal variations of canopy-level Urban Heat Island effect in the tropical city of Greater Kuala Lumpur
No full textA very few studies have evaluated and understood the temporal dynamics of UHI in many expanding tropical cities. Hence, this study investigated the temporal variations of canopy-level UHI in selected urban stations, namely Petaling Jaya (PJ) and Subang (SUB), of Greater Kuala Lumpur (GKL) using 2016’s hourly data set obtained from meteorological observatories. The association between meteorological factors and UHI Intensity (UHII) is evaluated using linear regression models and Pearson correlation analysis. The findings revealed positive thermal contrasts between urban and sub-urban stations with maximum UHII during dry, southwest monsoon season in PJ (June: 1.68 °C) and SUB (August: 1.29 °C) stations respectively. PJ station exhibited a distinct diurnal cycle with the maximum nocturnal UHII of 1.71 °C at about 8 p.m. after sunset under ideal meteorological conditions. The results also demonstrated that UHI events occurred more frequently at nights in urban stations in the magnitude range of 0–2 °C. Cooling at all urban sites starts around 2–3 p.m. with the highest rate of 0.73 °C/h and 0.96 °C/h in PJ and SUB stations. Meanwhile, relative humidity displayed a low positive correlation (r = 0.37, p ≥ 0.05) and a high negative correlation (r = −0.79, p < 0.05) with UHII in PJ and SUB stations respectively. The influence of wind speed on UHII is weak (r = −0.44, p < 0.05) in PJ station and strong (r = 0.83, p < 0.05) in SUB station. Overall, this study can be regarded as one of the comprehensive observational investigations of canopy-level UHI in a tropical city that provide vital inputs to enrich the tropical urban climate literacy
Novel palladium-guanine-reduced graphene oxide nanocomposite as efficient electrocatalyst for methanol oxidation reaction
No full textThe agglomeration of metal catalysts can limit the performance of fuel cells. Herein, an easy, scalable, one-pot microwave-assisted method is proposed to introduce guanine, which is a nucleobase found in deoxyribonucleic acid and ribonucleic acid, to the reduced graphene oxide-supported palladium via noncovalent functionalization. Considering the abundant amino, amide, and imino functional groups of guanine that act as anchoring sites, palladium nanoparticles of various shapes such as triangular, rectangular, circular, and diamond are uniformly distributed. The guanine itself is revealed to be catalytically active toward methanol oxidation reaction, serving as second catalyst. Consequently, the as-produced nanocomposite has a larger electrochemically active surface area (111.98 m2 g−1 vs. 63.80 m2 g−1), greater methanol electro-oxidation ability (1017.42 mA mg−1 vs. 359.80 mA mg−1), and higher stability in alkaline medium than its counterpart without guanine
Enrichment of PHA-accumulators for sustainable PHA production from crude glycerol
No full textPolyhydroxyalkanoates (PHAs) as biodegradable polymers produced by microorganisms with thermo-plastic properties are of high interest. In this study, PHA-accumulators were cultivated using crude glycerol and activated sludge in a sequencing batch reactor (SBR) with the aerobic dynamic feeding (ADF) strategy. This study aimed to enrich PHA-accumulators by evaluating the stability of the cultivation reactor followed by the effect of organic loading rate (OLR). The cultivation reactor was stable while maintaining a steady feast/famine (F/F) ratio. The increase of OLR from 360 mgC/(L·d) to 1000 mgC/(L·d) led to the increment of biomass concentration from less than 0.7 g/L to 2 g/L. The enriched mixed culture produced a maximum PHA content of 80 wt% in biomass dry weight with a production yield of 0.7 mg C PHA/mg C. The mixed culture were found to accumulate both 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3 HV) monomers at a HB:HV molar ratio of 60:40. Based on fluorescence in situ hybridization (FISH) analysis, Alphaproteobacteria and Betaproteobacteria were the most dominant species during peak PHA production. This method provides an option for resource recovery operation in converting waste to value-added products
Ice-templated graphene oxide/chitosan aerogel as an effective adsorbent for sequestration of metanil yellow dye
No full textGraphene oxide/chitosan aerogel (GOCA) was prepared by a facile ice-templating technique without using any cross-linking reagent for metanil yellow dye sequestration. The adsorption performance of GOCA was investigated by varying the adsorbent mass, shaking speed, initial pH, contact time, concentration and temperature. The combined effects of adsorption parameters and the optimum conditions for dye removal were determined by response surface methodology. GOCA exhibited large removal efficiencies (91.5–96.4%) over a wide pH range (3–8) and a high adsorption capacity of 430.99 mg/g at 8 mg adsorbent mass, 400 mg/L concentration, 35.19 min contact time and 175 rpm shaking speed. The adsorption equilibrium was best represented by the Langmuir model. GOCA could be easily separated after adsorption and regenerated for re-use in 5 adsorption-desorption cycles thereby maintaining 80% of its adsorption capability. The relatively high adsorption and regeneration capabilities of GOCA render it an attractive adsorbent for treatment of azo dye-polluted water