Evaluating the impact of a pre-recorded online video on doctor's knowledge and attitude towards leprosy in Sabah and Labuan - a quasi experimental study.

INTRODUCTION: Global actions have been implemented worldwide to eliminate leprosy. However, under-recognition and stigmatisation continue to be the challenges. In Sabah, the grade two disability rate was 0.15/100,000 population in 2019, implicating a significant delay in diagnosis. This study aimed to assess the knowledge and attitude towards leprosy and the impact of lecture intervention among doctors in Sabah and Labuan, Malaysia. MATERIALS AND METHODS: This study consists of two parts. First, a cross-sectional study on the knowledge of and attitude towards leprosy using an online quesitonnaire was conducted among doctors working in the primary care clinics and hospitals in Sabah and Labuan. Subsequently, the participants were asked to watched an online prerecorded video lecture on leprosy and to answered the same questionnaire. RESULTS: Of the 310 participants, one fifth (20.6%) had good knowledge and 36.5% had positive attitude towards leprosy. Being a specialist (adjusted odds ratio [aOR] 4.55, 95% confidence interval [CI] 2.17-9.57, p < 0.001), managed ≥ 5 leprosy cases (aOR 3.37, 95% CI 1.52-7.47, p = 0.003), and involved in educational activities related to leprosy within last year (aOR 4.7, 95% CI 1.69-13.04, p < 0.001) were the significant predictors of good knowledge. Working in tertiary care was significantly associated with good attitude towards leprosy (OR 2.19, 95% CI 1.22-3.94, p = 0.025). There was a significant improvement in participants' knowledge post-intervention (87.0% participants post-lecture vs 20.6% participants pre-lecture with good knowledge, p < 0.001). CONCLUSION: The proportion of doctors in Sabah and Labuan with good knowledge and attitude towards leprosy was low. Knowledge of leprosy improved significantly postintervention. This highlights the need for educational and training programmes to improve doctors' knowledge of leprosy.

Psychosocial burden of patients with atopic dermatitis at two tertiary referral centres in Malaysia.

BACKGROUND: Atopic dermatitis (AD) is a chronic pruritic skin disorder that affects up to 20% of children and 10% of adults. The disease course is unpredictable with periods of exacerbation and remission, thus having a significant impact on the mental health and quality of life (QOL). We evaluated the prevalence of anxiety and depression and their association with disease severity, QOL and their associated factors in adolescents (≥ 13 years old) and adults with AD. METHODS: A cross-sectional study was conducted involving patients aged ≥ 13 years with AD who fulfilled the Hanifin and Rajka diagnostic criteria. These patients were recruited from Hospital Queen Elizabeth, Kota Kinabalu and Hospital Kuala Lumpur between January 2020 to March 2021. Assessment instruments used were Scoring for Atopic Dermatitis (SCORAD), Patient-Oriented Eczema Measure (POEM), Dermatology Life Quality Index (DLQI) and Hospital Anxiety and Depression Scale (HADS). RESULTS: Of the 217 participants, 75 (34.6%) had mild eczema, 116 (53.5%) moderate eczema and 26 (12.0%) severe eczema with a mean SCORAD score of 30.4 (standard deviation [SD] = 4.70). Twenty-six (12.0%) and 17 (7.8%) had anxiety and depression, respectively. Patients with moderate to severe disease reported higher HADS-A (HADS-anxiety component), HADS-D (HADS-depression component), POEM, DLQI, itch, sleep loss and skin pain scores (p < 0.001 for all). Severe sleep loss (adjusted odd ratio [AOR] 12.41, p < 0.001) and hospitalisation in the past year (AOR 6.44, p = 0.004) were significant predictors for anxiety whereas those aged 41 to 60 (AOR 10.83, p = 0.020), having severe skin pain (AOR 6.12, p = 0.028), DLQI ≥ 10 (AOR 5.27, p = 0.002) and history of hospitalisation in the past year (AOR 12.73, p = 0.002) had increased risk for depression. CONCLUSION: The prevalence of anxiety was 12.0% while depression was 7.8% in our cohort. AD renders a significant burden on mental health and QOL with a higher impact on those with more severe disease. The use of screening tools such as HADS and DLQI for assessment of mental health and QOL should be considered to address the multidimensional burden of AD.

Template Assisted Microwave Synthesis of rGO-ZrO2 Composites: Efficient Photocatalysts Under Visible Light.

In this research, cetyltetraethyl ammonium bromide template assisted microwave procedure was utilized to synthesize reduced graphene oxide-zirconia (rGO-ZrO2) nanocomposites by varying the rGO composition (1, 2, 5 and 10 wt%). The physico-chemical characteristics of the nanocomposites were studied using X-ray diffraction (XRD), Raman, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), diffusive reflectance ultraviolet-visible (DRUV-vis), X-ray photoelectron spectroscopy (XPS) and N2-physisorption techniques. The results from XRD, Raman and DSC studies indicate that the increase in rGO concentration resulted in the delay in ZrO2 crystallization temperature and alteration of ZrO2 phase from monoclinic to tetragonal due to an effective incorporation of rGO nanosheets in ZrO2 structure. The rGO loading also have an influence in the morphology of nanocomposites, as sample with 10 wt% rGO possessed unique monolith like morphology with macro pores. All the nanocomposites were utilized as photocatalysts for degradation of crystal violet dye in visible light irradiation. The rGO-ZrO2 nanocomposites showed high reaction rates; the nanocomposite with 5 wt% rGO showed the superior photocatalytic performance as this sample possessed low band gap energy, high surface area, pore volume and presence of surface rGO-ZrO2 interactive species as well as the reactive -OH groups. In addition, the synthesized nanocomposites exhibited excellent recyclability for photocatalytic degradation.

Assessment of household use of iodized salt and adequacy of salt iodization: a cross-sectional National Study in Saudi Arabia.

OBJECTIVES: This study was conducted to assess household coverage with iodized salt in Saudi Arabia, and to determine adequacy of salt iodization. METHODS: A school-based cross-sectional study using WHO 30-cluster survey methodology. RESULTS: Analysis of 4242 salt samples using qualitative rapid test kit (RTK) revealed that 68.7% (95% CI 67.3-70.1%) were iodized with significant regional differences (p < 0.001). The highest iodized salt samples came from Makkah (82.3%), Riyadh (81.1%) and Maddinah (76.2%) regions, while the least iodized salt samples came from Hail (31.3%), Baha (53.0%), and Northern Borders (57.5%) regions. The national weighted proportion of households consuming iodizes salt was 69.8% (95% CI 69.4-71.2), which is below the Universal Salt Iodization (USI) goal (≥90% coverage). For validation, a quantitative iodometric titration method was used to analyze 775 representative salt samples screened iodized by RTK; iodine content of ≥15 ppm was found in 95.2% (95% CI 93.9-96.5) of samples with median iodine content 51 ppm (mean 50.4 ± 21.8). More than 70% of the iodized salt samples contained iodine concentration higher than the recommended national level (15-40 ppm). CONCLUSIONS: The study revealed inadequate consumption of iodized salt among Saudi households and explored marked regional heterogeneity. The majority of iodized salt samples contained iodine concentration more than the recommended level. These findings imply the need to launch a public awareness campaign on use of iodized salt. Legislation to ban production and sale of non-iodized salt sale for human consumption might be considered. A well-functioning monitoring system at factory level and surveillance system are crucially needed to ensure proper salt iodization and intake.

Supported Zeolite Beta Layers via an Organic Template-Free Preparation Route.

Layers of high silica zeolites, synthesized with an organic structure directing agent (OSDA) and grown onto porous support structures, frequently suffer from the thermal stress during the removal of OSDA via the calcination process. The different thermal expansion coefficients of the zeolite and the support material, especially when stainless steel is used as a support, causes enormous tension resulting in defect formation in the zeolite layer. However, the calcination is an easy procedure to decompose the OSDA in the pore system of the zeolite. Recently, methods to synthesize zeolite beta without the use of an organic structure directing agent have been described. In the present study, a seed-directed synthesis is used to prepare OSDA-free zeolite beta layers on stainless steel supports via an in situ preparation route. For the application as membrane, a porous stainless steel support has been chosen. The beta/stainless steel composites are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). To prove its possible application as a membrane, the beta/stainless steel composites were also tested by single gas permeances of H2, He, CO2, N2, and CH4.

A one-dimensional statistical mechanics model for nucleosome positioning on genomic DNA.

The first level of folding of DNA in eukaryotes is provided by the so-called '10 nm chromatin fibre', where DNA wraps around histone proteins (∼10 nm in size) to form nucleosomes, which go on to create a zig-zagging bead-on-a-string structure. In this work we present a one-dimensional statistical mechanics model to study nucleosome positioning within one such 10 nm fibre. We focus on the case of genomic sheep DNA, and we start from effective potentials valid at infinite dilution and determined from high-resolution in vitro salt dialysis experiments. We study positioning within a polynucleosome chain, and compare the results for genomic DNA to that obtained in the simplest case of homogeneous DNA, where the problem can be mapped to a Tonks gas. First, we consider the simple, analytically solvable, case where nucleosomes are assumed to be point-like. Then, we perform numerical simulations to gauge the effect of their finite size on the nucleosomal distribution probabilities. Finally we compare nucleosome distributions and simulated nuclease digestion patterns for the two cases (homogeneous and sheep DNA), thereby providing testable predictions of the effect of sequence on experimentally observable quantities in experiments on polynucleosome chromatin fibres reconstituted in vitro.

Application of TOPSIS and VIKOR improved versions in a multi criteria decision analysis to develop an optimized municipal solid waste management model.

Selecting a suitable Multi Criteria Decision Making (MCDM) method is a crucial stage to establish a Solid Waste Management (SWM) system. Main objective of the current study is to demonstrate and evaluate a proposed method using Multiple Criteria Decision Making methods (MCDM). An improved version of Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) applied to obtain the best municipal solid waste management method by comparing and ranking the scenarios. Applying this method in order to rank treatment methods is introduced as one contribution of the study. Besides, Viekriterijumsko Kompromisno Rangiranje (VIKOR) compromise solution method applied for sensitivity analyses. The proposed method can assist urban decision makers in prioritizing and selecting an optimized Municipal Solid Waste (MSW) treatment system. Besides, a logical and systematic scientific method was proposed to guide an appropriate decision-making. A modified TOPSIS methodology as a superior to existing methods for first time was applied for MSW problems. Applying this method in order to rank treatment methods is introduced as one contribution of the study. Next, 11 scenarios of MSW treatment methods are defined and compared environmentally and economically based on the waste management conditions. Results show that integrating a sanitary landfill (18.1%), RDF (3.1%), composting (2%), anaerobic digestion (40.4%), and recycling (36.4%) was an optimized model of integrated waste management. An applied decision-making structure provides the opportunity for optimum decision-making. Therefore, the mix of recycling and anaerobic digestion and a sanitary landfill with Electricity Production (EP) are the preferred options for MSW management.

Nanostructured Mg-Al hydrotalcite as catalyst for fine chemical synthesis.

This paper reviews the recent research of nanostructured Mg-Al hydrotalcite (Mg-Al HT) and its application as an efficient solid base catalyst for the synthesis of fine chemicals. Mg-Al HT has many beneficial features, such as low cost, selectivity, catalytic properties, and wide range of preparation and modification methods. They hold promise for providing sought-after, environmentally friendly technologies for the 21st century. Replacement of currently used homogeneous alkaline bases for the synthesis of fine chemicals by a solid catalyst can result in catalyst re-use and waste stream reduction. We introduce briefly the structure, properties and characterization of the nanostructured Mg-Al HT. The efficacy and benign applications of Mg-Al HT as an alternative solid base to homogenous catalysts in the synthesis of fine chemicals are then reviewed. The challenges for the future applications of Mg-Al HT in the synthesis of fine chemicals in terms of green protocol processes are discussed.

The associated risk of Blastocystis infection in cancer: A case control study.

Background: Blastocystis is an anaerobic intestinal protozoan. Nine Blastocystis subtypes (STs) were detected in humans. A subtype-dependent association between Blastocystis and different cancer types has been debated in many studies. Thus, this study aims to assess the possible association between Blastocystis infection and cancer, especially colorectal cancer (CRC). We also screened the presence of gut fungi and their association with Blastocystis. Methods: We used a case-control design; cancer patients and cancer-free (CF) participants. The cancer group was further sub-group into CRC group and cancers outside the gastrointestinal tract (COGT) group. Macroscopic and microscopic examinations were performed to identify intestinal parasites in participants' stool samples. Molecular and phylogenetic analyses were conducted to identify and subtype Blastocystis. Furthermore, gut fungi were investigated molecularly. Results: 104 stool samples were collected and matched between CF (n=52) and cancer patients (n=52); CRC (n=15) and COGT (n=37). As anticipated, Blastocystis prevalence was significantly higher among CRC patients (60%, P=0.002) and insignificant in COGT patients (32.4%, P=0.161) compared to CF group (17.3%). The most common subtypes were ST2 among cancer group and ST3 in the CF group. Conclusion: Cancer patients have a higher risk of Blastocystis infection compared to CF individuals (OR=2.98, P=0.022). Increased risk of Blastocystis infection was associated with CRC patients (OR=5.66, P=0.009). Nevertheless, further studies are required to understand the underlying mechanisms of Blastocystis and cancer association.

Balancing functional and health benefits of food products formulated with palm oil as oil sources.

Palm oil (PO) is widely utilised in the food industry and consumed in large quantities by humans. Owing to its bioactive components, such as fatty acids, carotenoids, vitamin E, and phenolic compounds, PO has been utilised for generations. However, public concern about their adverse effects on human health is growing. A literature search was conducted to identify fractionated palm oil processing techniques, proof of their health advantages, and potential food applications. Refined palm oil (RPO) is made from crude palm oil (CPO) and can be fractionated into palm olein (POl) and palm stearin (PS). Fractional crystallisation, dry fractionation, and solvent fractionation are the three basic fractionation procedures used in the PO industry. The composition of triacylglycerols and fatty acids in refined and fractionated palm oil and other vegetable oils is compared to elucidate the triacylglycerols and fatty acids that may be important in product development. It is well proven that RPO, POl, and PS extends the oil's shelf life in the food business. These oils have a more significant saturated fat content and antioxidant compounds than some vegetable oils, such as olive and coconut oils, making them more stable. Palm olein and stearin are also superior shortening agents and frying mediums for baking goods and meals. Furthermore, when ingested modestly daily, palm oils, especially RPO and POl, provide health benefits such as cardioprotective, antidiabetic, anti-inflammatory, and antithrombotic effects. Opportunities exist for fractionated palm oil to become a fat substitute; however, nutrition aspects need to be considered in further developing the market.

Detection of Bartonella sp. in ticks and their small mammal hosts in mangrove forests of Peninsular Malaysia.

Bacteria of the genus Bartonella have been known as emerging zoonotic pathogens for several human diseases including cat scratch disease, Carrion's disease and trench fever. Numerous species of small mammals have been reported to play a role as a suitable reservoir to many pathogenic Bartonella. These infections are thought to be transmitted through blood-feeding arthropod vectors such as ticks, fleas and lice. The purpose of this study is to detect the presence of Bartonella species from tick samples collected from small mammals in mangrove forests of Peninsular Malaysia. Herein, 38 individual ticks and their small mammals host were evaluated for the presence of Bartonella DNA by conventional PCR targeting the 16S rRNA intergenic spacer region (ITS) and partial sequencing of 460 bp from this locususing Bartonella genus-specific primers. Two tick individuals from Dermacentor auratus and Haemaphysalis hystricis collected from Rattus tiomanicus (host), were PCR-positive for Bartonella DNA amplification. No Bartonella amplification was possible in other tick species (Amblyomma sp.). Phylogenetic analysis of ITS fragments demonstrated that the sequences from ticks were closely related to Bartonella phoceensis, a species that has been reported from black rats (Rattus rattus) in Australia. This is the first report of a Bartonella bacteria detected in ticks from small mammals in Malaysia. Further research should be warranted to investigate the transmission of Bartonella and the potential impact of this zoonotic pathogen in animals and humans as this mangrove ecosystem is significant for local economy and tourism.

Nanolayer-like-shaped MgFe2O4 synthesised via a simple hydrothermal method and its catalytic effect on the hydrogen storage properties of MgH2.

In this study, the effect of nanolayer-like-shaped MgFe2O4 that is synthesised via a simple hydrothermal method on the performance of MgH2 for hydrogen storage is studied. MgH2 + 10 wt% MgFe2O4 is prepared by using the ball milling method. The MgFe2O4-doped MgH2 sample started to release H2 at approximately 250 °C, 90 °C and 170 °C lower than the milled and pure MgH2 respectively. At 320 °C, the isothermal desorption kinetic study has shown that the doped sample has desorbed approximately 4.8 wt% H2 in 10 min while the milled MgH2 desorbed less than 1.0 wt% H2. For isothermal absorption kinetics, the doped sample can absorb approximately 5.5 wt% H2 in 10 min at 200 °C. Meanwhile, the undoped sample absorbs only 4.0 wt% H2 in the same condition. The activation energy of 10 wt% MgFe2O4-doped MgH2 composite is 99.9 kJ mol-1, which shows a reduction of 33.1 kJ mol-1 compared to the milled MgH2 (133.0 kJ mol-1). X-ray diffraction spectra display the formation of new species which are Fe and MgO after dehydrogenation, and these new species are believed to act as the real catalyst that plays a crucial role in improving the sorption performance of the MgFe2O4-doped MgH2 system by providing a synergetic catalytic effect.

Elevated factor VIII in hereditary haemorrhagic telangiectasia (HHT): association with venous thromboembolism.

Hereditary haemorrhagic telangiectasia (HHT) causes chronic nasal and gastrointestinal haemorrhage. Prothrombotic agents are commonly used for severe haemorrhage. Thrombotic risks have not been defined. In order to identify prothrombotic variables in HHT patients, and assess their potential functional significance, a pilot ELISA-based study comparing plasma proteins in healthy individuals with HHT to age/sex-matched non-HHT controls was validated in a full study of 309 consecutive HHT-affected individuals. In the pilot study, factor VIII (FVIII) and von Willebrand factor antigen concentrations were elevated in the HHT group compared to non-HHT controls (p<0.0013, Mann-Whitney). Service laboratory measurements confirmed high FVIII:Ag in 125 HHT-affected individuals with no recent ill-health, intervention or venous thromboemboli. FVIII:Ag levels increased with age. Logistic regression also suggested an age-independent association with HHT-associated pulmonary arteriovenous malformations (AVMs). No association was demonstrated between FVIII:Ag and acute phase response, disseminated intravascular coagulation, ABO group, pulmonary artery pressure, or markers of HHT haemorrhage. Elevated FVIII:Ag were associated with shortened activated partial thromboplastin times (APTTs), and VTE:VTE affected 20/309 (6.5%) HHT-affected individuals, at median age 61(36-71) years. Four VTE occurred in factorV Leiden heterozygotes in the months following PAVM-associated brain abscess. The strongest association with VTE was with log-transformed FVIII:Ag measured 10-132 months from VTE (odds ratio 2.41, 95% confidence intervals 1.254, 4.612, p=0.008). Age made no additional contribution to VTE risk once adjusted for FVIII:Ag. In conclusion, HHT-related elevation of FVIII:Ag levels may influence thrombotic risk in HHT. Individualised risk-benefit considerations may be helpful in HHT management.

Maturity-Onset Diabetes of the Young: An Overview with Focus on the Middle East.

Today, there are more than 32 million patients with diabetes in the Middle East (ME), the number is expected to double by 2040. In contrast to Europe and North America and despite the high prevalence of diabetes in ME, epidemiological data about incident and types of diabetes in the region is very limited. Maturity-onset diabetes of the young (MODY) is a subtype of monogenic diabetes representing 2-5% of all diabetes patients. The disease is autosomal dominant mode of inheritance characterized by ß-cell malfunction below the age of 35 years. To date, there are 15 different MODY forms that have been identified; each has a distinct genetic etiology. It is very common that MODY is misdiagnosed between with type 1 or type 2 diabetes. Hence, accurate genetic diagnosis is crucial to individualize the treatment and to improve glycaemia control. New technologies such as next-generation sequencing (NGS) offer an excellent alternative to screen and identify causative MODY mutations. In this review, we summarize the main clinical and genetic characteristics for each MODY form. In addition, we shed light on MODY studies that have been executed in the ME region.

Chemical Vapor Deposition Synthesis and Optical Properties of Nb2O5 Thin Films with Hybrid Functional Theoretical Insight into the Band Structure and Band Gaps.

Nb2O5 is an important material able to exist in many polymorphs with unique optical properties and morphologies that are dependent on the synthetic route. Here we report a novel ambient-pressure chemical vapor deposition route to Nb2O5 via aerosol-assisted chemical vapor deposition. The amorphous as-deposited films were annealed in air to obtain the the three most stable crystal structures: orthorhombic, tetragonal, and monoclinic. The films were thoroughly characterized for their material properties, and an in-depth study into the optical properties was carried out using state-of-the-art hybrid functional theory that allowed more insight into the optical properties of the materials.

Lattice Boltzmann algorithm to simulate isotropic-nematic emulsions.

We present lattice Boltzmann simulations of the dynamical equations of motion of a drop of isotropic fluid in a nematic liquid crystal solvent, both in the absence and in the presence of an electric field. The coupled equations we solve are the Beris-Edward equations for the dynamics of the tensor order parameter describing the nematic solvent, the Cahn-Hilliard equation for the concentration evolution, and the Navier-Stokes equations for the determination of the instantaneous velocity field. We implement the lattice Boltzmann algorithm to ensure that spurious velocities are close to zero in equilibrium. We first study the effects of the liquid crystal elastic constant, K, anchoring strength, W, and surface tension, sigma, on the shape of the droplet and on the director field texture in equilibrium. We then consider how the drop behaves as the director field is switched by an applied electric field. We also show that the algorithm allows us to follow the motion of a drop of isotropic fluid placed in a liquid crystal cell with a tilted director field at the boundaries.

Enhanced hydrogen storage properties of MgH2 co-catalyzed with K2NiF6 and CNTs.

The composite of MgH2/K2NiF6/carbon nanotubes (CNTs) is prepared by ball milling, and its hydrogenation properties are studied for the first time. MgH2 co-catalyzed with K2NiF6 and CNTs exhibited an improvement in the onset dehydrogenation temperature and isothermal de/rehydrogenation kinetics compared with the MgH2-K2NiF6 composite. The onset dehydrogenation temperature of MgH2 doped with 10 wt% K2NiF6 and 5 wt% CNTs is 245 °C, which demonstrated a reduction of 25 °C compared with the MgH2 + 10 wt% K2NiF6 composite. In terms of rehydrogenation kinetics, MgH2 doped with 10 wt% K2NiF6 and 5 wt% CNTs samples absorbed 3.4 wt% of hydrogen in 1 min at 320 °C, whereas the MgH2 + 10 wt% K2NiF6 sample absorbed 2.6 wt% of hydrogen under the same conditions. For dehydrogenation kinetics at 320 °C, the MgH2 + 10 wt% K2NiF6 + 5 wt% CNTs sample released 3.3 wt% hydrogen after 5 min of dehydrogenation. By contrast, MgH2 doped with 10 wt% K2NiF6 released 3.0 wt% hydrogen in the same time period. The apparent activation energy, Ea, for the dehydrogenation of MgH2 doped with 10 wt% K2NiF6 reduced from 100.0 kJ mol-1 to 70.0 kJ mol-1 after MgH2 was co-doped with 10 wt% K2NiF6 and 5 wt% CNTs. Based on the experimental results, the hydrogen storage properties of the MgH2/K2NiF6/CNTs composite is enhanced because of the catalytic effects of the active species of KF, KH and Mg2Ni that are formed in situ during dehydrogenation, as well as the unique structure of CNTs.

Effect of Na3FeF6 catalyst on the hydrogen storage properties of MgH2.

The effects of Na3FeF6 catalyst on the hydrogen storage properties of MgH2 have been studied for the first time. The results showed that for the MgH2 sample doped with 10 wt% Na3FeF6, the onset dehydrogenation temperature decreased to 255 °C, which was 100 °C and 162 °C lower than those of the as-milled and as-received MgH2 sample, respectively. The re/dehydrogenation kinetics were also significantly enhanced compared to the un-doped MgH2. The absorption kinetics showed that the as-milled MgH2 only absorbed 3.0 wt% of hydrogen at 320 °C in 2 min of rehydrogenation, but about 3.6 wt% of hydrogen was absorbed within the same period of time after 10 wt% Na3FeF6 was added to MgH2. The desorption kinetics showed that the MgH2 + 10 wt% Na3FeF6 sample could desorb about 3.8 wt% of hydrogen in 10 min at 320 °C. In contrast, the un-doped MgH2 sample desorbed only 0.2 wt% of hydrogen in the same period of time. The activation energy for the decomposition of the as-milled MgH2 was 167.0 kJ mol(-1), and this value decreased to 75.0 kJ mol(-1) after the addition of 10 wt% Na3FeF6 (a reduction by about 92.0 kJ mol(-1)). It is believed that the in situ formation of the active species of NaMgF3, NaF and Fe during the heating process could enhance the hydrogen storage properties of MgH2, due to the catalytic effects of these new species.

Mercury in dental amalgam: Are our health care workers at risk?

Dental amalgam in fillings exposes workers to mercury. The exposure to mercury was investigated among 1871 dental health care workers. The aim of the study was to evaluate the risk of mercury exposure among dental compared to nondental health care workers and to determine other risk factors for mercury exposure. Respondents answered questionnaires to obtain demographic, personal, professional, and workplace information and were examined for their own amalgam fillings. Chronic mercury exposure was assessed through urinary mercury levels. In total, 1409 dental and 462 nondental health care workers participated in the study. Median urine mercury levels for dental and nondental health care workers were 2.75 µg/L (interquartile range [IQR] = 3.0175) and 2.66 µg/L (IQR = 3.04) respectively. For mercury exposure, there were no significant risk factor found among the workers involved within the dental care. The Mann-Whitney test showed that urine mercury levels were significantly different between respondents who eat seafood more than 5 times per week compared to those who eat it less frequently or not at all (p = 0.003). The urinary mercury levels indicated significant difference between dental workers in their practice using squeeze cloths (Mann-Whitney test, p = 0.03). Multiple logistic regression showed that only the usage of cosmetic products that might contain mercury was found to be significantly associated with the urinary mercury levels (odds ratio [OR] = 15.237; CI: 3.612-64.276). Therefore, mean urinary mercury levels of health care workers were low. Exposure to dental amalgam is not associated with high mercury exposure. However, usage of cosmetic products containing mercury and high seafood consumption may lead to the increase of exposure to mercury. IMPLICATIONS: Exposure to the high levels of mercury from dental amalgam can lead to serious health effects among the dental health care workers. Nationwide chronic mercury exposure among dental personnel was assessed through urinary mercury levels. Findings suggest low urinary mercury levels of these health care workers. Exposure to dental amalgam is not associated with high mercury exposure. However, the usage of cosmetic products containing mercury and high seafood consumption may lead to the increase of exposure to mercury.

A single-source precursor approach to solution processed indium arsenide thin films.

This paper reports the synthesis of the novel single-source precursor, [{(MeInAs t Bu)3}2(Me2InAs( t Bu)H)2] and the subsequent first report of aerosol-assisted chemical vapour deposition of InAs thin films. Owing to the use of the single-source precursor, highly crystalline and stoichiometric films were grown at a relatively low deposition temperature of 450 °C. Core level XPS depth profiling studies showed some partial oxidation of the film surface, however this was self-limiting and disappeared on etch profiles. Valence band XPS analysis matched well with the simulated density of state spectrum. Hall effect measurements performed on the films showed that the films were n-type with promising resistivity (3.6 × 10-3 Ω cm) and carrier mobility (410 cm2 V-1 s-1) values despite growth on amorphous glass substrates.