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Fertility levels and differentials in Malaysia / Lim Evone
No full textThe main objective of this paper is to examine the fertility differentials among women by selected socio-economic and demographic variables in Malaysia. Over the past 40 years, the fertility level in Malaysia has declined considerably due to social and economic changes and has been below the replacement level of 2.1 children since 2013. The problem of population aging in Malaysia rises due to the increasing people’s life expectancy and declining fertility rates. It is critical for Malaysian policymakers to have a deeper understanding of the factors influencing fertility behavior. The fifth series of the Malaysian Population and Family Survey (MPFS-5) collected in 2014 is used as the main data source. Bivariate analysis is conducted on a sample of 5,146 women to determine how fertility varies with selected socio-economic and demographic factors such as women’s age, stratum, state, ethnicity, the highest education level of women, age at first marriage, the current employment status of women and the status of family planning. Moreover, this paper examines the significant relationship between these variables and the difference in the number of children ever born by women. This study found that all of the selected factors have a significant effect on fertility differentials in Malaysia. In brief, fertility patterns are different across socio-demographic subgroups and over time
Relative contribution of arms and legs through repetitive assisted sit-to-stand motion in individuals with incomplete spinal cord injury / Musfirah Abd Aziz
No full textSit-To-Stand (SitTS) exercise is one of important prerequisites to achieve some functional independence goals in everyday life especially for individuals undergoing rehabilitation In general, the execution of SitTS in spinal cord injury (SCI) patients involves motor function in both upper and lower extremities. The use of arm support in particular is a very significant element while executing SitTS movement for SCI population. In addition, application of functional electrical stimulation (FES) onto the quadriceps muscles is one of the prescribed management for incomplete SCI to improve muscle action for simple lower limb movements. However, the relative contribution of upper and lower extremities during SitTS has not been studied thoroughly. Therefore, the objective of this study is to determine the contribution of arm and leg during repetitive SitTS in incomplete SCI participants with and without FES. Two motor incomplete SCI participants performed repetitive SitTS-to fatigue exercise challenge. Three sets of SitTS test were completed with five-minute resting period were allocated in between set, with mechanomyography (MMG) sensors attached over the belly of the quadriceps muscles bilaterally. A total of 399 and 463 SitTS trials were completed without and with FES respectively by both participants. A SitTS cycle can be divided into three phases; Phase 1 (Preparation to stand), Phase 2 (Seat-off) and Phase 3 (Initiation of hip extension) which contributed to 23 ± 7%, 16 ± 4% and 61 ± 6% of the SitTS cycle respectively. Overall, the mean time to complete each FES-SitTS cycle between early trials for each set was identified to be significantly shorter compared to the final trials in each set (p<0.0005). The contribution of leg and arm during SitTS movement varied in different participants based on their legs Medical Research Council (MRC) muscle grade. During early Phase
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2 of voluntary and assisted SitTS, in terms of percentage of total participant�s body weight, both participants showed higher arms percentage contribution compared to their legs. Meanwhile throughout the end of Phase 3 in the SitTS activity, the percentage of arms contribution increased only for Participant 1 due to his right leg condition that was weak. For Participant 2, the percentage of arms contribution decreased as the contribution of leg percentage increased. For both conditions, there were significant average differences in the percentage of total body weight contribution between early Phase 2 and the end of Phase 3 for arm (p<0.001) and leg (p<0.001). This study highlighted the relative contribution of arm support in SitTS activity in two individuals with motor incomplete SCI. The finding might serve as a reference for SCI individuals to do a safe SitTS protocol hence future rehabilitative SitTS exercise where strength training of arm and leg can be emphasised
Acculturative stress, social support and oral health related quality of life among international graduate students in Malaysian public universities / Hala Fathalla Ben Ghasheer
No full textBackground: Oral health related quality of life (OHRQoL) reflects the impact of the oral
condition on physical, social, and psychological functioning and well-being from an
individual’s perspective. It is an important health outcome that is influenced by several
factors which together are known as the determinants of health. Psychosocial factors are
among many other factors that have a crucial role in shaping oral health. Understanding
their role in relation to diminished oral health has gained more interest in recent years
since such factors could serve as points of intervention for new oral health promotion
strategies. Aim: This study aimed to investigate the relationship of acculturative stress
and social support with the OHRQoL among international graduate students in Malaysian
public universities. Methods: A total of 312 international graduate students completed a
web-based questionnaire, including measures of acculturative stress (ASSIS-36),
perceived stress (PSS-4), social support (MSPSS-12), oral health perceptions (global
rating item), and oral health-related quality of life (OHRQoL, OIDP-8). The hypotheses
of the conceptual model were tested employing structural equation modelling using
partial least squares (SEM-PLS) with the support of SmartPLS. Results: Twenty-seven
percent (27.1 %) of the variance in OHRQoL was explained by acculturative stress,
perceived stress, social support, and oral health perceptions. The path coefficients
between oral health perception and OHRQoL was the strongest (β = - 0.385, P < 0.001).
Acculturative stress directly influenced OHRQoL (β=0.20, P=0.009), and indirectly
through perceived stress (β=0.05, P=0.019). Social support had a moderating effect
(t=1.98) on the psychosocial domain of OHRQoL and mediated the relationship between
perceived stress and OHRQoL (β=0.046, P= 0.02). The overall predictive power of the
model was 23 %. Conclusion: Results indicated that acculturative stress, perceived stress,
and social support are among the predictors of OHRQoL. Oral health perceptions and
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acculturative stress were the most significant predictors that contributed the largest
amount to the model. The findings emphasize the potential role of psychosocial factors
in relation to oral health. The empirical evidence of this study could facilitate the planning
of targeted strategies by incorporating stress reduction and social support enhancement.
Such strategies might be a new promising way to enhance OHRQoL since these elements
can be modified and response to interventions.
Keywords: OHRQoL - Acculturative stress – Perceived stress- Social support�International students - Malaysia - Structural Equation Modellin
Development of b-type and multi-ion doped carbonated hydroxyapatite bioceramics / Marjan Safarzadeh
No full textThe present research is aimed to investigate the effect of varying the carbonate to phosphate (CO32−/ PO43‒) molar ratios from 0.5 to 5 on the physical and mechanical properties of carbonated hydroxyapatite (CHA) synthesized by a wet chemical method. The sintering was performed under dry carbon dioxide atmosphere at 900 °C to maintain the B-type CHA structure. It was found that increases in CO32−/ PO43‒ ratio was accompanied by an increase in the c/a lattice ratio. The diffraction peaks of the synthesized 0.5-5 CHA powders exhibited a single phase material except for 5CHA which revealed the some minor calcite or (CaCO3) as a secondary phase. The sintering studies indicated that all CHA was thermally stable and retained the apatite structure after sintering. The relative density of the sintered CHA was found to decrease along with the Vickers hardness and fracture toughness as the CO32−/ PO43‒ ratio increased from 0.5 to 4. The improvement in the mechanical properties was associated with improvement in the relative density and the larger grain size of the sintered samples.
The CHA with upper limit of carbonate was chose as the optimum CHA for the next investigations. Subsequently, evaluate the effect of varying sintering temperature (800 °C, 900 °C, 1000 °C and 1100 °C) under the dry CO2 atmosphere on the compacted CHA sample. The results shown that all samples retained single phase B-type CHA except at 1100 °C which was accompany with the formation of CaO in the apatite structure. Increasing sintering temperature led to a gradual decrease in the carbonate content of the CHA pellets and an increase in mechanical properties up to 1000 °C. In particular, the HV and KIc values increased with increasing sintering temperature.
An in vitro bioactivity test was evaluated on the 0.5-4 CHA pellets using simulated body fluid (SBF) solution. It was found that increasing the carbonate content enhanced the solubility of CHA pellets and increased the thickness of the apatite layer on the sample’s surface. Lastly the effect of multi-ions (Mg2+, SiO44-, Zn2+ and Cu2+) doping on the properties of carbonated hydroxyapatite (CHA) prepared by a wet chemical method was investigated. Different combinations of ions were doped into the CHA and the as-synthesized compacts were sintered at 900 °C and wet CO2 atmosphere prior to body characterization. It was found that regardless of ions doping, the lattice structure of the CHA was not disrupted. In addition, secondary phases were not detected for all the multi-ions doped samples. The XRD and FTIR results further confirmed the presences of a B-Type CHA in the as-synthesized and sintered samples. The XRD analysis revealed that the lattice parameters (c/a ratio) increased with dopant addition and resulted in a smaller crystallite size. The FESEM examination also showed the presences of smaller grain size for the multi-ions doped CHA samples thus indicating that the doping was beneficial in suppressing grain coarsening in carbonated hydroxyapatite.
The main advantageous of this synthesis method is low production costs and relatively time-saving that exhibited higher mechanical properties at lower sintering temperature in CO2 atmosphere. Additionally, the presence of minor elements in CHA is more promising to enhance biomedical properties
Assessment of various groundwater recharge methods in the lower Kelantan River Basin, Malaysia / Nur Hayati Hussin
No full textGroundwater recharge is a natural process to replenish the aquifer system. Since 1930s the groundwater demand has risen as it has supported 70% of water supply in Lower Kelantan River Basin. However, a comprehensive study on groundwater recharge mechanism has never been reported. This study evaluated various methods to identify recharge flow processes using stable isotopes of deuterium (2H) and oxygen-18 (18O), tritium (3H), radon (222Rn) and hydrogeochemical (HC) and quantify recharge rate using chloride mass balance (CMB), water table fluctuation (WTF), temperature-depth profile (TDP) and groundwater modelling coupled with water balance GM(WB) followed by the construction of a conceptual model of recharge mechanism. Stable isotope indicates local rainfall origin from monsoon meteoric air masses that have experienced primary and secondary evaporation while tritium indicates rainfall of modern water age of <5 year to 10 years. Rainfall is the main source of surface water and diffuse recharge into the groundwater system. The fast transmit time of rainfall runoff, that percolates and infiltrates through unsaturated zone into aquifer has recharged Layer 1 with modern water age while deep aquifer (Layer 2 and Layer 3) contains a mix of recharge water of modern to sub-modern water caused by long transmit time and mixing with available water in the aquifer. Isotopes and hydrogeochemical methods reveal that the interactions of river-groundwater and aquifer-aquifer within the basin were triggered by infiltration, leaking and mixing besides controlled by the major processes of silicate weathering, dissolution and ion exchange. Through this process, groundwater in shallow aquifer (Layer 1) evolved from CaHCO3 to NaHCO3 towards the coastal area. As the depth increases, groundwater shows a trend of depletion in stable isotopes, decreasing in tritium and increasing in radon concentration. Recharge estimation using CMB, WTF, TDP and GM(WB) showed high variability within 8% to 68% of annual rainfall. CMB ranges from 16% to 68%, WTF 11% to 19%, TDP 8% to 11%, and GM(WB) 11% of annual rainfall, respectively. At 11%, recharge from GM(WB) was the best method for estimation because the model was constructed and calibrated using locally derived input parameters. GM(WB) is the only method involved with calibration and validation process to reduce the uncertainty. The WTF method based on long-term hydrological records gives a reasonable recharge value, in good agreement with GM(WB) and these methods can be paired to ensure the reliability of recharge value approximation in the same ranges. Applying various methods has given insight into methods selection to quantify recharge at LKRB and it is recommended that a lysimeter is installed as a direct method to estimate recharge. The integrated outcomes of groundwater recharge mechanism is useful as a baseline study for effective and sustainable groundwater resources management at LKRB and Malaysia
Energy-efficient data transmission with clustering and compressive sensing in wireless sensor networks / Mukil Alagirisamy
No full textOne of the most important application of wireless sensor network is environmental monitoring. The application involves lifetime of sensor nodes for longer duration associating its energy module. Wireless sensor nodes deployed in sensing field aggregate enormous amount of sensed data and transfer them to the sink. The inherent limitation of energy carried within the battery of sensor nodes fetches extreme difficulty to acquire adequate network lifetime, becoming a bottleneck in forwarding data to sink. Hence the motivation is to reduce the amount of data transfer and attain energy efficiency. This is achieved by clustering and compressive sensing techniques. First objective is to reduce the transmission burden on sensors to attain energy efficiency. The solution is achieved by unequal clustering with appropriate cluster head selection and dual sink. These two criterions minimizes the energy holes and preserves the network lifetime. Energy-Aware Unequal Clustering routing algorithm with Dual sink (EAUC-DUAL) and Energy based Cluster Head selection Unequal Clustering with Dual sink (ECH-DUAL) are proposed. EAUC –DUAL uses static and mobile sink. EAUC-DUAL suggests smaller size clusters around static sink and the entire clusters in the network transmit their data only to the nearest sink providing load balancing and minimizes the hotspot. In the extended ECH-DUAL algorithm in addition to dual sink a new cluster head selection method is proposed for unequal clustering. It focuses on balancing the burden of cluster heads by suitable selection of Tentative Cluster Head (TCH) and Final Cluster Head (FCH). Simulation results interprets the network lifetime of EAUC –DUAL is two times more than the LEACH algorithm. In the extended ECH-DUAL algorithm the network lifetime of ECH-DUAL is twice greater than the network lifetime of EAUC-DUAL. Second objective is to reduce the transfer volume of sensed data and attaining energy efficiency. Conventional sampling results in high amount of sensed data. Hence the framework of Intelligent Neighbor-Aided Compressive Sensing (INACS) is proposed emphasizing on compressive sensing at source, data forwarding based on highest correlation to the neighbor node and exact recovery at the sink. Compressive sensing techniques and data forwarding reduces the volume of sensed data and the number of transmissions. Simulation results conclude better energy efficiency and reconstruction accuracy. The energy consumption in INACS is 0.29 times lesser than the existing protocol.The third objective focus on the reduction in observational cost and transmission cost through compressive sensing and data forwarding techniques respectively. The data forwarding should be performed considering the link capacity of nodes and available bandwidth. A framework Perceptron-based Optimal Routing (POR) and Perceptronbased Routing with Moderate Traffic Intensity (PRMTI) is proposed for data forwarding. The data forwarding process is initiated considering the network resources. POR is suggested for scarce network resources and PRMTI for abundant network resources. Simulation has been performed on energy consumption and number of transmissions. Residual energy of POR is 0.26 times higher and PRMTI is 0.14 times higher than the
existing protocol. The simulation results of clustering algorithms, INACS and Perceptron framework are validated using various data analysis methods
Study on cation exchange of a lead coordination polymer targeting dynamic mixed cation doped and mixed-valent coordination polymers / Hamisu Aliyu Mohammed
Get PDFSolid solution in Metal-Organic Coordination Polymers (MOCPs) is an emerging synthetic pathway for modifying chemical compositions and has been expansively investigated. It has been demonstrated to be an important tool for engineering novel functional materials that otherwise have not been synthesized via the conventional technique. Although stable solid material with variable functionalities and intriguing structural motifs could be engineered by judicious selection of multivariate metal centers and multifunctional ligands. However, solid solution featuring mixed valence in MOCP is rare. Motivated by the ability of Pb2+ to adopt range of coordination numbers (CN) and chemical environments (CE), in addition to its flexibility to readily undergo cation exchange owing to its low electronegativity, we opted for solid solution in Pb-based MOCP. Herein, we exploited a dynamic 3D, Pb-based MOCPs that contain 1D moiety featuring 3 distinctive Pb2+ sites each with different CN and CE that can potentially undergo cation exchange with exogenous divalent and aliovalent including mono- or trivalent cations. Under optimized condition, we achieved to our knowledge the first, hetero-valent, single and multiple valent substituted MOCP featuring cation vacancy. In addition to this, under the guidance of Pearson’s Hard-Soft Acid-Base (HSAB) principle, we gained the control of the process and tune the % of cations exchange under appropriate conditions. A tunable photoluminescent (PL) emission exhibiting good antenna effect and retention of the original 3D MOCP was observed when doped with as little as 6 wt% of Eu3+. Remarkably, the PL intensity of the Eu3+ substituted MOCP increases as the amount of Eu3+ increases even up to 80 wt. %, which is also a rather rare case and the first, to the best of our knowledge in MOCP solid solution. 10 wt. % Eu3+ substituted MOCP was found to have a significant conductivity improvement at 25 oC. Fe2+ substituted MOCP was also found to have some magnetic hysteresis at room temperature, another very rare case of mononuclear or cluster Fe2+ doped to show some hysteresis at RT. The formation of solid solution and phase purity of these compounds were confirmed by single crystal and powder X-ray diffractions, SEM-EDX, ICP-OES as well as XPS
Factors influencing employees’ ethical behavior: Empirical study of employees in Iraqi organizations / Husam Mohammed Kamil Alhaboose
Get PDFIn contemporary organizations, ethics has become one of the most vital aspects of organizational sustenance in today’s competitive business world. Earlier studies have considered employees as a potential source of success for an organization. Moreover, prior studies have designated the essential role of ethical leadership in influencing employees’ ethical behavior. Therefore, this study tries to contribute to the literature by examining the direct effect of ethical leadership on employees’ ethical behavior via the two-mediating role of ethical climate and organizational justice. Most importantly, moral identity was also identified as a boundary condition on the relationship of ethical leadership, ethical climate, organizational justice, and ethical behavior of employees. Data were collected through questionnaires which were completed by 620 full-time employees working at 33 Iraqi organization from five Iraqi provinces and involved in manufacturing, retailing, medical, insurance, information technology, legal, finance, and telecommunication sectors. Structural Equation Modeling (SEM) was used to test the model and data analysis was carried out using Structural Equation Modelling–Partial Least Square (SEM-PLS) and PROCESS macro. The results showed that ethical leadership behavior has a significant relationship with ethical behavior. The study also revealed the relationship between ethical leadership and employees’ ethical behavior is positively mediated by work ethical climate and organizational justice. Moreover, the moderation role of moral identity was a significant on the relationship of ethical leadership, and employees’ ethical behavior, on the other hand, was insignificant between work ethical climate, organizational justice, and employees’ ethical behavior. The theoretical model of this study was underpinned by social exchange and social learning theory to improve the exchange relationship between managers and employees as well as to enhance employees’ ethical behavior. This study provides theoretical and practical contributions to business ethics and leadership studies
Urban-rural gaps in the prevalence of hypertension, obesity and diabetes in Malaysia / Govindamal Thangiah
No full textRapid economic growth has driven urbanization in developed and developing economies. However, it also created several problems, such as a deterioration in health conditions worldwide and widening of urban-rural and income inequality. A major consequence of urbanization include the rising prevalence of non-communicable diseases, cardiovascular disease (CVD) and its risk factors, such as hypertension, obesity and diabetes. The rapid nutrient and physical activity transition due to urbanization and the peculiar form of economic transformation has impacted the CVD risk factors. Rising urban-rural differences in health profiles and CVD risk factors in both locations over years in Malaysia prompted this research study. This study aims to examine if differences exist between urban and rural hypertension, obesity and diabetes prevalence, and if it is so, to determine their causes. This study also seeks to examine income related hypertension, obesity and diabetes inequalities in urban and rural areas. Unlike most past studies, this study also examines the impact of cumulative lifestyle risk factors (CLRF), (physical activity, diet intake and smoking) on the prevalence of hypertension, obesity and diabetes prevalence in both urban and rural areas. A sample of 7301 Malaysian adults from rural and urban locations in Malaysia who voluntarily enrolled in this community-based health survey from years 2007-2010 were used. Participant’s socioeconomic status (SES), physical activity, diet, smoking status and demographic information were recorded through questionnaires. A non-linear Blinder-Oaxaca decomposition analysis was applied to identify the causes of urban-rural differences in hypertension, obesity and diabetes, concentration index and its decomposition analysis was used to assess the burden of these diseases across the income spectrum and multivariate logistic regression analysis was applied to assess the effect of CLRF on hypertension, obesity and diabetes. Findings from this study suggest that demographic factors and SES are among the main factors that cause the urban-rural differences in obesity and diabetes prevalence. Also, the study showed a higher intensity of income related obesity inequality compared to hypertension and diabetes in urban areas. In rural areas, the intensity of income related obesity inequality was highest followed by diabetes and hypertension. Overall, SES was the main cause of income related hypertension, diabetes and obesity inequalities in urban and rural areas except for income related obesity inequality in rural areas where demographic factors explained most the inequalities. Finally, while the findings of the study showed a significant and positive association between CLRF score and obesity as well as diabetes prevalence in urban areas, CLRF score was insignificantly associated with diabetes, hypertension and obesity prevalence in rural areas. Overall, the results suggest that health policy makers should enhance health-care facilities in rural areas, create more awareness on these diseases among urban population, impose tax on products with high sugar and fat content and tobacco especially in urban areas and to eliminate income related health inequalities, policy makers should consider reducing the prices of healthy products and health related products and services such as gym and more
Feature extraction and description for retinal fundus image registration / Roziana Ramli
No full textRetinal fundus image registration (RIR) is performed to align two or more fundus
images. A general framework of a feature-based RIR technique comprises of preprocessing,
feature extraction, feature descriptor, matching and estimating geometrical
transformation. The RIR is mainly performed for super-resolution, image mosaicking and
longitudinal study applications to assist diagnosis and monitoring retinal diseases.
Registering image pair from these applications involve a combination of challenges such
as overlapping area and rotation between images. The challenges of the overlapping area
and rotation can be addressed at feature extraction and feature descriptor stages of the
feature-based RIR technique, respectively. To address the overlapping area, a reliable and
repeatable anatomical information such as retinal vessels is required. However, finding
the feature points on retinal vessels can be challenging due to noises with similar structure
representation as the vessels. For rotation, a distinctive descriptor is necessary to
characterise the feature points on retinal vessels that are lack of textural information and
exhibit repetitive patterns in the local patches of fundus image. Therefore, this study
proposed new feature extraction and feature descriptor methods for feature-based RIR
technique to address these issues. The proposed feature extraction method extracts the
feature points on retinal vessels by considering the characteristics of the retinal vessels
and noises. The proposed feature descriptor method characterises the feature points with
statistical properties obtained from the surrounding region of the feature points. The
proposed work is tested on five public datasets, namely, CHASE_DB1, DRIVE, HRF,
STARE and FIRE. Aspects of the evaluation include evaluating the extraction accuracy
of the proposed feature extraction method and the registration accuracy of the proposed
feature-based RIR technique. Experimental results show that the proposed feature
extraction method attained the highest overall extraction accuracy (86.021%) and outperformed the existing feature extraction methods; Harris corner (41.613%), SIFT
(16.164%), SURF (18.929%), Ghassabi’s (28.280%) and D-Saddle (20.509%). The
registration success rate of the proposed feature-based RIR technique (67.164%) is also
outperformed the existing feature-based RIR techniques; Harris-PIIFD (3.731%), GDBICP
(27.612%), Ghassabi’s-SIFT (12.687%), H-M 16 (16.418%), H-M 17 (19.403%) and
D-Saddle-HOG (11.940%). The influence of the overlapping area and rotation on the
proposed feature-based RIR technique are significant but the weakest among the
evaluated feature-based RIR techniques