pH-dependent structural transitions in cationic ionizable lipid mesophases are critical for lipid nanoparticle function.

Lipid nanoparticles (LNPs) are advanced core-shell particles for messenger RNA (mRNA) based therapies that are made of polyethylene glycol (PEG) lipid, distearoylphosphatidylcholine (DSPC), cationic ionizable lipid (CIL), cholesterol (chol), and mRNA. Yet the mechanism of pH-dependent response that is believed to cause endosomal release of LNPs is not well understood. Here, we show that eGFP (enhanced green fluorescent protein) protein expression in the mouse liver mediated by the ionizable lipids DLin-MC3-DMA (MC3), DLin-KC2-DMA (KC2), and DLinDMA (DD) ranks MC3 ≥ KC2 > DD despite similar delivery of mRNA per cell in all cell fractions isolated. We hypothesize that the three CIL-LNPs react differently to pH changes and hence study the structure of CIL/chol bulk phases in water. Using synchrotron X-ray scattering a sequence of ordered CIL/chol mesophases with lowering pH values are observed. These phases show isotropic inverse micellar, cubic Fd3m inverse micellar, inverse hexagonal [Formula: see text] and bicontinuous cubic Pn3m symmetry. If polyadenylic acid, as mRNA surrogate, is added to CIL/chol, excess lipid coexists with a condensed nucleic acid lipid [Formula: see text] phase. The next-neighbor distance in the excess phase shows a discontinuity at the Fd3m inverse micellar to inverse hexagonal [Formula: see text] transition occurring at pH 6 with distinctly larger spacing and hydration for DD vs. MC3 and KC2. In mRNA LNPs, DD showed larger internal spacing, as well as retarded onset and reduced level of DD-LNP-mediated eGFP expression in vitro compared to MC3 and KC2. Our data suggest that the pH-driven Fd3m-[Formula: see text] transition in bulk phases is a hallmark of CIL-specific differences in mRNA LNP efficacy.

Planetary boundaries transgressions: A review on the implications to public health.

This literature review systematically examines the impacts of violating planetary boundaries from 2009 to 2023, emphasizing the implications for human health. Planetary boundaries define safe operational limits for Earth's systems, and their transgression poses significant threats to environmental stability and public health. This paper reviews extensive research on the health effects of breaches in these boundaries, including climate change, biodiversity loss, freshwater use, and aerosol loading. The review integrates findings from numerous studies, providing a critical overview of health impacts across various global regions. The analysis underscores the intricate links between planetary boundaries breaching impacts, highlighting urgent policy and governance challenges. The study's outcomes aim to inform policymakers, businesses, and communities, promoting sustainable development and resilience in the face of escalating global challenges.

A state-of-the-art review of metal oxide nanoflowers for wastewater treatment: Dye removal.

Dye wastewater consists of high solids concentrations, heavy metals, minor contaminants, dissolved chemical oxygen demand, and microorganisms. Nanoflowers are nanoparticles that resemble flowers when viewed at a microscopic level. Inorganic metal oxide nanoflowers have been discovered to be a potential source for overcoming this situation. Their flower-like features give them a higher surface area to volume ratio and porosity structure, which can absorb a significant amount of dye. The metal oxide nanoflower synthesized from different synthesis methods is used to compare which one is cost-effective and capable of generating a large scale of nanoflower. This review has demonstrated outstanding dye removal efficiency by applying inorganic nanoflowers to dye removal. Since both adsorption and photocatalytic reactions enhance the dye degradation process, complete dye degradation could be achieved. Meanwhile, the inorganic metal oxide nanoflowers' exemplary reusability characteristics with negligible performance drop further prove that this approach is highly sustainable and may help to save costs. This review has proven the momentum of obtaining high dye removal efficiency in wastewater treatment to conclude that the metal oxide nanoflower study is worth researching.

Menopausal hormone therapy and risk of venous thromboembolism: The story so far.

Menopausal hormone therapy (MHT) is known to increase the risk of venous thromboembolism (VTE), which includes deep vein thrombosis, pulmonary embolism, and less frequently cerebral vein thrombosis, but the absolute risk for a given patient is very low. After starting MHT, the risk of VTE seems to be at its highest, declining to the non-HRT user baseline level of risk after stopping. Whether estrogen-only or estrogen-progestin HRT combination is linked to a similar risk of VTE is unclear from the available evidence. The aim of this study is to evaluate the risks of developing VTE in relation to different types as well as different modes of administration of MHT through a database search including PubMed, MEDLINE, Google Scholar, Cochrane Library, and others in order to provide the women carers with the up-to-date and evidence-based guidelines and recommendations while counseling the post-menopausal women enquiring on use of hormonal therapies either to alleviate the menopausal symptoms or to prevent the long-term sequelae of estrogen deficiency.

On sait que l'hormonothérapie ménopausique (MHT) augmente le risque de thromboembolie veineuse (TEV), qui comprend la thrombose veineuse profonde, l'embolie pulmonaire et, moins fréquemment, la thrombose veineuse cérébrale, mais le risque absolu pour un patient donné est très faible. Après le début du MHT, le risque de TEV semble être à son plus haut niveau, diminuant jusqu'au niveau de risque de base des non-utilisatrices de THS après l'arrêt. Les preuves disponibles ne permettent pas de savoir si un THS à base d'œstrogène seul ou d'association œstroprogestative est lié à un risque similaire de TEV. Le but de cette étude est d'évaluer les risques de développer une TEV par rapport à différents types ainsi qu'à différents modes d'administration du MHT grâce à une recherche dans des bases de données comprenant PubMed, MEDLINE, Google Scholar, Cochrane Library et autres afin de fournir aux femmes les soignants avec les lignes directrices et recommandations à jour et fondées sur des preuves tout en conseillant les femmes ménopausées qui se renseignent sur l'utilisation de thérapies hormonales, soit pour soulager les symptômes de la ménopause, soit pour prévenir les séquelles à long terme d'une carence en œstrogènes.

Adsorbing DNA to Mica by Cations: Influence of Valency and Ion Type.

Ion-mediated attraction between DNA and mica plays a crucial role in biotechnological applications and molecular imaging. Here, we combine molecular dynamics simulations and single-molecule atomic force microscopy experiments to characterize the detachment forces of single-stranded DNA at mica surfaces mediated by the metal cations Li+, Na+, K+, Cs+, Mg2+, and Ca2+. Ion-specific adsorption at the mica/water interface compensates (Li+ and Na+) or overcompensates (K+, Cs+, Mg2+, and Ca2+) the bare negative surface charge of mica. In addition, direct and water-mediated contacts are formed between the ions, the phosphate oxygens of DNA, and mica. The different contact types give rise to low- and high-force pathways and a broad distribution of detachment forces. Weakly hydrated ions, such as Cs+ and water-mediated contacts, lead to low detachment forces and high mobility of the DNA on the surface. Direct ion-DNA or ion-surface contacts lead to significantly higher forces. The comprehensive view gained from our combined approach allows us to highlight the most promising cations for imaging in physiological conditions: K+, which overcompensates the negative mica charge and induces long-ranged attractions. Mg2+ and Ca2+, which form a few specific and long-lived contacts to bind DNA with high affinity.

Techno-economic assessment of hydrotreated vegetable oil as a renewable fuel from waste sludge palm oil.

To date, the development of renewable fuels has become a normal phenomenon to solve the problem of diesel fuel emissions and the scarcity of fossil fuels. Biodiesel production has some limitations, such as two-step processes requiring high free fatty acids (FFAs), oil feedstocks and gum formation. Hydrotreated vegetable oil (HVO) is a newly developed international renewable diesel that uses renewable feedstocks via the hydrotreatment process. Unlike FAME, FFAs percentage doesn't affect the HVO production and sustains a higher yield. The improved characteristics of HVO, such as a higher cetane value, better cold flow properties, lower emissions and excellent oxidation stability for storage, stand out from FAME biodiesel. Moreover, HVO is a hydrocarbon without oxygen content, but FAME is an ester with 11% oxygen content which makes it differ in oxidation stability. Waste sludge palm oil (SPO), an abundant non-edible industrial waste, was reused and selected as the feedstock for HVO production. Techno-economical and energy analyses were conducted for HVO production using Aspen HYSYS with a plant capacity of 25,000 kg/h. Alternatively, hydrogen has been recycled to reduce the hydrogen feed. With a capital investment of RM 65.86 million and an annual production cost of RM 332.56 million, the base case of the SPO-HVO production process was more desirable after consideration of all economic indicators and HVO purity. The base case of SPO-HVO production could achieve a return on investment (ROI) of 89.03% with a payback period (PBP) of 1.68 years. The SPO-HVO production in this study has observed a reduction in the primary greenhouse gas, carbon dioxide (CO2) emission by up to 90% and the total annual production cost by nearly RM 450 million. Therefore, SPO-HVO production is a potential and alternative process to produce biobased diesel fuels with waste oil.

Health impacts from TRAPs and carbon emissions in the projected electric vehicle growth and energy generation mix scenarios in Malaysia.

Road transport contributes over 70% of air pollution in urban areas and is the second largest contributor to the total carbon dioxide emissions in Malaysia at 21% in 2016. Transport-related air pollutants (TRAPs) such as NOx, SO2, CO and particulate matter (PM) pose significant threats to the urban population's health. Malaysia has targeted to deploy 885,000 EV cars on the road by 2030 in the Low Carbon Mobility Blueprint (LCMB). This study aims to quantify the health co-benefits of electric vehicle adoption from their impacts on air quality in Malaysia. Two EV uptake projections, i.e. LCMB and Revised EV Adoption (REVA) projections, and five electricity generation mix scenarios were modelled up to 2040. We used comparative health risk assessment to estimate the potential changes in mortality and burden of diseases (BoD) from the emissions in each scenario. Intake fractions and exposure-risk functions were used to calculate the burden from respiratory diseases (PM2.5, NOx, SO2, CO), cardiovascular diseases and lung cancer (PM2.5). Results showed that along with a net reduction of carbon emissions across all scenarios, there could be reduced respiratory mortality from NOx by 10,200 mortality (176,200 DALYs) and SO2 by 2600 mortality (45,400 DALYs) per year in 2040. However, there could also be additional 719 mortality (9900 DALYs) per year from PM2.5 and 329 mortality (5600 DALYs) from CO per year. The scale of reduction in mortality and BoD from NOx and SO2 are significantly larger than the scale of increase from PM2.5 and CO, indicating potential net positive health impacts from the EV adoption in the scenarios. The health cost savings from the reduced BoD of respiratory mortality could reach up to RM 7.5 billion per year in 2040. In conclusion, EV is a way forward in promoting a healthy and sustainable future transport in Malaysia.

Combining molecular dynamics simulations and x-ray scattering techniques for the accurate treatment of protonation degree and packing of ionizable lipids in monolayers.

The pH-dependent change in protonation of ionizable lipids is crucial for the success of lipid-based nanoparticles as mRNA delivery systems. Despite their widespread application in vaccines, the structural changes upon acidification are not well understood. Molecular dynamics simulations support structure prediction but require an a priori knowledge of the lipid packing and protonation degree. The presetting of the protonation degree is a challenging task in the case of ionizable lipids since it depends on pH and on the local lipid environment and often lacks experimental validation. Here, we introduce a methodology of combining all-atom molecular dynamics simulations with experimental total-reflection x-ray fluorescence and scattering measurements for the ionizable lipid Dlin-MC3-DMA (MC3) in POPC monolayers. This joint approach allows us to simultaneously determine the lipid packing and the protonation degree of MC3. The consistent parameterization is expected to be useful for further predictive modeling of the action of MC3-based lipid nanoparticles.

The Malay version of the caregiver assessment of function and upset instrument (Malay-CAFU): a translation and validation study among informal stroke caregivers.

BACKGROUND: Post-stroke complications affect the informal caregivers equally as the stroke survivors, especially those who have a moderate to worst prognosis in functional capacity recovery. Caregiver Assessment of Function and Upset (CAFU) is one of the common tools used in both research and clinical practice to measure the patient's dependency level and the stroke caregivers' upset level. OBJECTIVE: This study aimed to translate and validate the CAFU instrument into the Malay language and test the validity and reliability of the CAFU among informal stroke caregivers in Malaysia. METHODS: A standard forward-backward translation method was employed to translate CAFU. Subsequently, 10 expert panels were included in the validation process, and thereafter reliability testing was conducted among 51 stroke caregivers. The validation of the instrument was determined by computing the content validity indices (CVIs), and we used the Cronbach's alpha method to explore the internal consistency of the overall score and subscales scores of the Malay-CAFU. Finally, the explanatory factor analysis used principal component extraction and a varimax rotation to examine construct validity. RESULTS: All items of the Malay-CAFU had satisfactory item-level CVI (I-CVI), with values greater than 0.80, and the scale-level CVI (S-CVI) was 0.95. These results indicate that the Malay-CAFU had good relevancy. The internal consistency for the reliability test showed a Cronbach's alpha value of 0.95 for the overall score. The eigenvalues and scree plot supported a two-factor structural model of the instrument. From the explanatory factor analysis, the factor loadings ranged from 0.82 to 0.90 and 0.56 to 0.83, respectively. CONCLUSION: The Malay-CAFU questionnaire is a valid and reliable instrument to assess the dependence level of stroke survivors and the upset level of informal stroke caregivers in Malaysia.

Children's exposure to air pollution in a natural gas industrial area and their risk of hospital admission for respiratory diseases.

The rapid expansion of the natural gas industry to meet the global demand have raised environmental health concerns. Few studies have found that areas with natural gas industrial activity have poor air quality. However, the negative health impacts of ambient air pollution in a natural gas industrial area remain unclear. This study aimed to explore the relationship between short-term exposure to air pollution and hospital admissions for respiratory diseases among children in a natural gas industrial area in Bintulu, Malaysia. Daily hospital admissions for respiratory diseases among children were collected from a hospital in Bintulu from 2010 to 2019. Data on six air pollutants (PM10, PM2.5, SO2, NO2, O3, and CO) in the study area were obtained from the Department of Environment Malaysia. Quasi-Poisson time series regressions with distributed lag non-linear models (DLNM) were applied to explore the associations between ambient air pollution and childhood hospitalisations for respiratory diseases. Stratification analyses were performed by gender and age group to identify the vulnerable populations. A 10 µg/m3 increased PM2.5 and SO2 was associated with hospital admissions for respiratory diseases among children with the greatest relative risk of RR 1.089 (95% CI 1.001-1.183) at cumulative lag 0-2 days and RR 1.229 (95% CI 1.073-1.409) at cumulative lag 0-6 days, respectively. There was no significant association between short-term exposure of PM10, NO2, CO, and O3 with childhood respiratory hospitalisation. The association between PM2.5 and SO2 exposure and hospital admissions for childhood respiratory diseases in the two pollutants model remained statistically significant. There were stronger associations in younger children aged 0-4 years and girls. This study reveals that short-term exposure to SO2 was associated with a higher risk of respiratory hospitalisations among children in Bintulu than PM2.5. Better air quality control is necessary for children's health living in the natural gas industrial area.

Cultural Beliefs on the Causes of Cleft Lip and/or Palate in Malaysia: A Multicenter Study.

OBJECTIVE: To identify the cultural beliefs about the causes of cleft among parents of patients with nonsyndromic cleft lip and/or palate in a multiethnic society in Malaysia and the difficulties encountered in receiving cleft treatment. DESIGN: A descriptive cross-sectional multicenter study based on a study questionnaire was conducted of parents of patients with cleft lip and/or palate. SETTING: Three centers providing cleft care from different regions in Malaysia: the national capital of Kuala Lumpur, east coast of peninsular Malaysia, and East Malaysia on the island of Borneo. PARTICIPANTS: Parents/primary caregivers of patients with cleft lip and/or palate. RESULTS: There were 295 respondents from different ethnic groups: Malays (58.3%), indigenous Sabah (30.5%), Chinese (7.1%), Indian (2.4%), and indigenous Peninsular Malaysia and Sarawak (1.7%). Malay participants reported that attributing causes of cleft to God's will, superstitious beliefs that the child's father went fishing when the mother was pregnant or inheritance. Sabahans parents reported that clefts are caused by maternal antenatal trauma, fruit picking, or carpentry. The Chinese attribute clefts to cleaning house drains, sewing, or using scissors. Cultural background was reported by 98.3% of participants to pose no barrier in cleft treatment. Those from lower socioeconomic and educational backgrounds were more likely to encounter difficulties while receiving treatment, which included financial constraints and transportation barriers. CONCLUSION: There is a wide range of cultural beliefs in the multiethnic society of Malaysia. These beliefs do not prevent treatment for children with cleft. However, they face challenges while receiving cleft treatment, particularly financial constraints and transportation barriers. Such barriers are more likely experienced by parents from lower income and lower education backgrounds.

Effect of drying on the physical and chemical properties of palm kernel oil.

BACKGROUND: Palm kernel is the edible seed of the oil palm fruit obtained during the palm oil milling process. For efficient processing and storage, the moisture content of palm kernel must be reduced to an optimal level by drying. This study aimed to see how drying influenced the physical structure and physicochemical properties of palm kernel and oil. Before and after drying, the free fatty acid (FFA), color, fatty acid composition, Fourier transform infrared, thermal properties and structure of palm kernel were investigated. RESULTS: Results show that drying significantly (P < 0.05) reduced FFA and color of palm kernel oil. Drying also significantly affected (P < 0.05) composition of some fatty acids in palm kernel oil such as capric acid, lauric acid, myristic acid, palmitic acid and oleic acid. However, drying did not affect palm kernel and palm kernel oil functional groups and thermal properties. After drying, structural damage of palm kernel was observed. CONCLUSION: Based on these findings, the quality of kernel oil may be maintained after drying, and it can even be improved based on lower FFA content. © 2022 Society of Chemical Industry.

Hand hygiene knowledge, perception, and self-reported performance among nurses in Kelantan, Malaysia: a cross-sectional study.

BACKGROUND: Nurses interact with patients 24 hours a day, and this connection has the potential to raise the risk of infection transmission to patients. Nursing plays a vital role in pre-venting healthcare-associated infections (HCAIs) by ensuring that hand hygiene (HH) practises are followed and maintained. The purpose of this study was to evaluate nurses' knowledge, perceptions, and self-reported HH performance scores, as well as their correlation, in tertiary care hospitals in Kelantan, Malaysia. METHODS: A cross-sectional study was undertaken in all four Kelantan tertiary care hospitals from December 2019 to February 2020. A stratified random selection method was used to obtain a sample of 438 registered nurses. A validated WHO self-administered HH knowledge and perception questionnaire for healthcare personnel was used to measure HH knowledge, perception, and self-reported HH performance. RESULTS: The mean (SD) score of knowledge was 15.08 (1.96) out of the total 25. The score of perception participants towards HH was 68.02 (10.14) out of the total 81 and the average self-reported HH performance was 87.58 (12.03) out of 100. Pearson's correlation analysis showed significant positive correlations between perception and knowledge scores; r (436) =0.17, p<0.001 and Perception and self-reported HH performance scores; r (436) =0.27, p<0.001. CONCLUSIONS: There is a strong link between knowledge and perception scores. Lack of understanding of HH during patient care might lead to a negative perception, which can affect overall self-reported HH performance. The need of monitoring and maintaining HH knowledge among nurses was established in this study.

Temperature sensing utilizing unclad plastic optical fiber with a balloon-like bent structure.

A plastic optical fiber (POF) temperature sensor with high sensitivity is experimentally demonstrated in this work. The temperature sensor is realized by a combination of macrobending and an unclad region in the fabrication of its sensor head. The POF sensor is bent into a balloon-like structure in order to introduce the effect of macrobending. For the optimization of the sensor performance, the bending radius of the balloon-like structure is varied. Experimental results suggest that the performance is optimized when the bending radius is fixed at 55 mm. With this amount of bending radius, temperature sensitivity of up to ${22.2} \times {{1}}{{{0}}^{- 3}}^\circ {{\rm{C}}^{- 1}}$ can be achieved in the range from 40°C to 80°C, with linearity of 0.99 and resolution of 0.45°C. This technique is found to improve the POF temperature sensitivity in comparison to previous developments.

Classification of community-acquired outbreaks for the global transmission of COVID-19: Machine learning and statistical model analysis.

BACKGROUND: As Coronavirus disease 2019 (COVID-19) pandemic led to the unprecedent large-scale repeated surges of epidemics worldwide since the end of 2019, data-driven analysis to look into the duration and case load of each episode of outbreak worldwide has been motivated. METHODS: Using open data repository with daily infected, recovered and death cases in the period between March 2020 and April 2021, a descriptive analysis was performed. The susceptible-exposed-infected-recovery model was used to estimate the effective productive number (Rt). The duration taken from Rt > 1 to Rt < 1 and case load were first modelled by using the compound Poisson method. Machine learning analysis using the K-means clustering method was further adopted to classify patterns of community-acquired outbreaks worldwide. RESULTS: The global estimated Rt declined after the first surge of COVID-19 pandemic but there were still two major surges of epidemics occurring in September 2020 and March 2021, respectively, and numerous episodes due to various extents of Nonpharmaceutical Interventions (NPIs). Unsupervised machine learning identified five patterns as "controlled epidemic", "mutant propagated epidemic", "propagated epidemic", "persistent epidemic" and "long persistent epidemic" with the corresponding duration and the logarithm of case load from the lowest (18.6 ± 11.7; 3.4 ± 1.8)) to the highest (258.2 ± 31.9; 11.9 ± 2.4). Countries like Taiwan outside five clusters were classified as no community-acquired outbreak. CONCLUSION: Data-driven models for the new classification of community-acquired outbreaks are useful for global surveillance of uninterrupted COVID-19 pandemic and provide a timely decision support for the distribution of vaccine and the optimal NPIs from global to local community.

Dorsal Hand Vein Image Enhancement Using Fusion of CLAHE and Fuzzy Adaptive Gamma.

Enhancement of captured hand vein images is essential for a number of purposes, such as accurate biometric identification and ease of medical intravenous access. This paper presents an improved hand vein image enhancement technique based on weighted average fusion of contrast limited adaptive histogram equalization (CLAHE) and fuzzy adaptive gamma (FAG). The proposed technique is applied using three stages. Firstly, grey level intensities with CLAHE are locally applied to image pixels for contrast enhancement. Secondly, the grey level intensities are then globally transformed into membership planes and modified with FAG operator for the same purposes. Finally, the resultant images from CLAHE and FAG are fused using improved weighted averaging methods for clearer vein patterns. Then, matched filter with first-order derivative Gaussian (MF-FODG) is employed to segment vein patterns. The proposed technique was tested on self-acquired dorsal hand vein images as well as images from the SUAS databases. The performance of the proposed technique is compared with various other image enhancement techniques based on mean square error (MSE), peak signal-to-noise ratio (PSNR), and structural similarity index measurement (SSIM). The proposed enhancement technique's impact on the segmentation process has also been evaluated using sensitivity, accuracy, and dice coefficient. The experimental results show that the proposed enhancement technique can significantly enhance the hand vein patterns and improve the detection of dorsal hand veins.

A novel and stable way for energy harvesting from Bi2Te3Se alloy based semitransparent photo-thermoelectric module.

In this research, due to the present pandemic of COVID-19, we are proposing a stable and fixed semitransparent photo-thermoelectric cell (PTEC) module for green energy harvesting. This module is based on the alloy of Bismuth Telluride Selenide (Bi2Te3Se), designed in a press tablet form and characterized under solar energy. Here, both aspects of solar energy i.e., light and heat are utilized for both energy production and water heating. The semitransparent PTEC converts heat energy directly to electrical energy due to the gradient of temperature between two electrodes (top and bottom) of thermoelectric cells. The PTEC is 25% transparent, which can be varied according to the necessity of the utilizer. The X-ray diffraction of material and electric characterization of module i.e., open-circuited voltage (VOC) and Seebeck coefficient were performed. The experimental observations disclose that in the proposed PTEC module with an increment in the average temperature (TAvg) from 34 to 60 °C, results in the rise of VOC âˆ¼ 2.4 times. However, by modifying the size of heat-absorbing top electrode and by increasing the temperature gradient through the addition of water coolant under the bottom electrode, an uplift in the champion device results in as increment of VOC ∼5.5 times and Seebeck coefficient obtained was -250 µV/0C, respectively. Results show that not only the selection of material but also the external modifications in the device highly effective the power efficiency of the devices. The proposed modules can generate electric power from light and utilize the penetrating sunlight inside the room and for the heating of the water which also acts as a coolant. These semitransparent thermoelectric cells can be built-in within windows and roofs of buildings and can potentially contribute to green energy harvesting, in situations where movement is restricted locally or globally.

Development and Validation of a Malay Version of the Questionnaire on Pornography Attitudes and Exposure for Youth in Kelantan.

BACKGROUND: The aim of the study is to develop and validate the Malay version of the questionnaire assessing the extent of pornography exposure (PORQUE) among youth in Kelantan. METHODS: 'Youth' was defined as a person aged between 15 and 24 years, while 'pornography' refers to any material that depicts sexual activity or erotic behaviour. The development phase consisted of a literature review, an expert panel review, face validation and a pre-test. Fifty college students from a randomly selected higher learning institutions were invited to participate in the pilot test, whereas 150 and 198 different students from the same institutions participated in exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), respectively. RESULTS: EFA suggested a five-factor solution with factor loadings ranging from 0.449 to 0.891 and a Cronbach's alpha ranging from 0.904 to 0.966. The CFA of the attitude questions also proved a good fitting model with good fit indices: comparative fit index (CFI) robust = 0.907; Tucker-Lewis fit index (TLI) robust = 0.901; root mean square error of approximation (RMSEA) robust = 0.073; standardised root mean square residual (SRMR) = 0.060. The factor loadings ranged from 0.544 to 0.906, whereas the Raykov's rho ranged from 0.886 - 0.974. CONCLUSION: Based on EFA and CFA, the attitude sections of the newly developed Malay version of the PORQUE were found to be psychometrically valid.

Stochastic SIS Modelling: Coinfection of Two Pathogens in Two-Host Communities.

A pathogen can infect multiple hosts. For example, zoonotic diseases like rabies often colonize both humans and animals. Meanwhile, a single host can sometimes be infected with many pathogens, such as malaria and meningitis. Therefore, we studied two susceptible classes S 1 ( t ) and S 2 ( t ) , each of which can be infected when interacting with two different infectious groups I 1 ( t ) and I 2 ( t ) . The stochastic models were formulated through the continuous time Markov chain (CTMC) along with their deterministic analogues. The statistics for the developed model were studied using the multi-type branching process. Since each epidemic class was assumed to transmit only its own type of pathogen, two reproduction numbers were obtained, in addition to the probability-generating functions of offspring. Thus, these, together with the mean number of infections, were used to estimate the probability of extinction. The initial population of infectious classes can influence their probability of extinction. Understanding the disease extinctions and outbreaks could result in rapid intervention by the management for effective control measures.

Correlation between grafted nanoparticle-matrix polymer interface wettability and slip in polymer nanocomposites.

Controlling and understanding the flow properties of polymer nanocomposites (PNC) is very important in realising their potential for various applications. In this study we report molecular dynamics simulation studies of slip between a rotating polymer-grafted nanoparticle and the surrounding free linear matrix chains. By varying the interface wettability between the nanoparticle and matrix chains defined by the parameter f, the ratio of the graft to the matrix chain length, or the graft chain density, Σ, we were able to tune the interface slip, δ, significantly. Both f and Σ alter the interface wettability by changing the matrix chain penetration depth, λ, into the graft chain layer. We observed a large value of δ at smaller f or Σ which reduces with an increasing value of the respective parameters. Since interface slip is also likely to affect other properies of PNCs, like viscosity and the glass transition, we suggest that these parameters could become useful tools to control the flow and mechanical properties of PNCs made with grafted nanoparticles.