Inclusion of third-person perspective in CAVE-like immersive 3D virtual reality role-playing games for social reciprocity training of children with an autism spectrum disorder

Universal Access in the Information Society - The present study aimed to improve the ability of children with autism to recognize emotions correctly. We used our third-person perspective...     

Molecular dynamics investigations on the interfacial energy and adhesive strength between C60-filled carbon nanotubes and metallic surface

The mechanical and adhesive properties of C₆₀@(10,10) carbon nanopeapods (CNPs) adhering to gold surfaces are investigated by atomistic simulations. The effects of C₆₀ fill density, tube length, surrounding temperature, and peeling velocity on the adhesion behavior are studied. Results show that the interfacial binding energy of CNPs (which depends on the C₆₀ fill density and temperature) is 2.0∼4.4% higher than that of (10,10) single-walled CNTs and 3.4∼4.7% lower than that of (5,5)@(10,10) double-walled CNTs (DWCNTs). Despite their lower interfacial binding energy, CNPs have a higher adhesive strength than that of DWCNTs (1.53 nN vs. 1.4 nN). Distinct from the inner tubes of DWCNTs, which have continuum mechanical properties, the discrete C₆₀ molecules that fill CNPs exhibit unique composite mechanical properties, with high flexibility and bend-buckling resistance. The bend-buckling forces for CNPs filled with a low/medium fill density of C₆₀ are approximately constant. When the fill density is 1 C₆₀ molecule per nanometer length, the bend-buckling force dramatically increases.     

Catalytic behavior of vanadium substituted mesoporous molecular sieves

A series of V-MCM-41 samples with different pore sizes has been systematically investigated with both gas and liquid phase reactions. Methanol oxidation has been performed in the gas phase on these catalysts. Turnover frequencies are normalized by oxygen uptake measured under reaction conditions. A strong effect of pore size on the catalytic activity was observed in the form of a “volcano curve” and may be correlated with a variation in the local bond angle of Si–O–V. Considering this effect, the catalytic activity may be ‘tuned' to maximum by varying the pore size. As expected, the same effect was observed in the liquid phase oxidation of cyclohexene. In order to interpret the pore size effect, the reaction rates of both the gas phase and liquid phase oxidation were then correlated with the variation of edge energies of V K-edge XANES on these MCM-41 catalysts. Additional reactions were performed in the liquid phase to compare the activity of V-MCM-41 with that of crystalline vanadium and titanium silicalite zeolites. The possible causes of the difference in the catalytic behaviors of these materials is also discussed.     

Lubrication Studies with Alumina-on-Alumina, Steel-on-Steel, and Steel-on-Alumina Bearing Systems

In metal bearing systems, good lubricants for boundary lubrication generally show chemical interaction with the bearing surface under the conditions of temperature and pressure generated in the sliding contact. In this study, tests in a four-ball wear tester have been used to compare lubricants under similar loadings using steel-on-steel, steel-on-alumina, and alumina-on-alumina bearing systems. In general, the alumina appears to be far less reactive with lubricants than steel. Alumina-on-alumina bearing systems do show a sensitivity to lubricant chemical composition with generally higher wear values than the other two bearing systems. Steel-on-alumina bearing systems generally show better wear characteristics than the all-alumina systems which indicates the improved chemical interactions between the steel and the lubricant. This study shows that the chemical reactivity of the lubricant with the bearing surface is important in the wear process.     

Health impacts associated with the implementation of a national petrol-lead phase-out program (PLPOP): evidence from Taiwan between 1981 and 2007

Background and objective

In 1981, a petrol-lead phase-out program (PLPOP) was launched in Taiwan for the abatement of environmental lead emissions. The present study was set out to examine whether the reduction of environmental lead emissions would result in the decrease in mortality rates of various diseases based on national data between 1981 and 2007.

Method

The national mortality data were obtained from the Office of Statistics of the Taiwan Department of Health (Taiwan DOH). Standardized mortality ratios (SMRs) were calculated based on 2000 WHO world standard population. Gasoline consumptions were obtained from the Bureau of Energy.

Results

The mean blood lead levels (BLLs) had decreased dramatically from approximately 20.14 μg/dl in the leaded petrol phase to 3 μg/dl or lower in the unleaded petrol phase. From 1981 to 2007, the mortality (per 100,000 people) was decreased from 146.2 to 43.8 for cerebrovascular disease, from 85.3 to 44.4 for heart disease, from 35.4 to 6.6 for hypertensive disease, from 21.3 to 17.3 for nephrosis, and from 810.2 to 491.6 for all causes. By taking the confounders (including economic growth rate, per capita income, tobacco consumption, and medical resources) into account, the decreases in SMRs for all causes, cerebrovascular disease, and nephrosis were found to be highly correlated with the decrease in petrol lead emissions (p-values = 0.001, < 0.001, 0.020, respectively).

Conclusion

Our results clearly show that the implementation of the PLPOP was associated with a decline in mortality rates in several diseases that have been associated with lead exposure, even after adjustment for a number of relevant confounders.     

Changing blood lead levels and DNA damage (comet assay) among immigrant women in Taiwan

Background

International marriage has had a rapid growth in recent years in Taiwan. However, little is known about the blood lead levels and DNA damage levels among immigrant women from resource-limited countries.

Objective

This study (a) explored differences between immigrant women and native women in demographic characteristics, blood lead levels, and DNA damage levels, and (b) identified risk factors that are associated with blood lead concentrations and DNA damage levels after immigration.

Methods

We used a structured questionnaire to collect data on socio-demographic status from (a) 71 immigrant women who had resettled in 2006 in Taichung, Taiwan and (b) 83 native women who live in the same area. Each study participant provided blood samples for lead and metal measurements, complete blood count examination, and the comet assay to measure degree of DNA damage.

Results

Immigrant women had higher mean blood lead concentration (2.23 ± 1.63 vs. 1.63 ± 1.00 μg/dl; p = 0.04) and lower mean blood zinc level (6.22 ± 2.22 vs. 6.89 ± 2.44 mg/l; p = 0.07) than native women. Resettlement time was a determinant to decrease blood lead and DNA damage levels among immigrants in Taiwan. Multiple linear regression analysis confirmed a statistically significant association between blood lead level and DNA damage, while zinc had a protective effect.

Conclusions

Public health agencies should focus on primary prevention and providing screening programs for this vulnerable population. An immigrant women's cohort should been established to follow-up and improve for elevated lead exposure families.     

Nickel(II) Coordination Polymers Supported by Bis-pyridyl-bis-amide and Angular Dicarboxylate Ligands: Role of Ligand Flexibility in Iodine Adsorption

Reactions of N‚N’-bis(3-pyridylmethyl)oxalamide (L¹), N‚N’-bis(4-pyridylmethyl)oxalamide (L²), or N,N’-bis(3-pyridylmethyl)adipoamide) (L³) with angular dicarboxylic acids and Ni(II) salts under hydro(solvo)thermal conditions afforded a series of coordination polymers: {[Ni(L¹)(OBA)(H₂O)]·H₂O}_n (H₂OBA = 4,4-oxydibenzoic acid), 1, {[Ni(L¹)(SDA)(H₂O)₂]·H₂O·CH₃OH}_n (H₂SDA = 4,4-sulfonyldibenzoic acid), 2, {[Ni(L²)(OBA)]·C₂H₅OH}_n, 3, {[Ni(L²)(OBA)]·CH₃OH}_n, 4, {[Ni₂(L²)(SDA)₂(H₂O)₃]·5H₂O}_n, 5, {[Ni₂(L²)(SDA)₂(H₂O)₃]·H₂O·2C₂H₅OH}_n, 6, {[Ni(L³)(OBA)(H₂O)₂]·2H₂O}_n, 7, {[Ni(L³)(SDA)(H₂O)₂]·2H₂O}_n, 8, and {[Ni(L³)₀.₅(SDA)(H₂O)₂]·0.5C₂H₅OH}_n, 9, which have been structurally characterized by using single-crystal X-ray crystallography. Complex 1 exhibits an interdigitated 2D layer with the 2,4L2 topology and 2 is a 2D layer with the sql topology, while 3 and 4 are 3D frameworks resulting from polycatenated 2D nets with the sql topology and 5 and 6 are 2-fold interpenetrated 3D frameworks with the dia topology. Complexes 7 and 8 are 1D looped chains and 9 is a 2D layer with the 3,4L13 topology. The various structural types in 1–9 indicate that the structural diversity is subject to the flexibility and donor atom position of the neutral spacer ligands and the identity of the angular dicarboxylate ligands, while the role of the solvent is uncertain. The iodine adsorption of 1–9 was also investigated, demonstrating that that the flexibility of the spacer L¹–L³ ligands can be an important factor that governs the feasibility of the iodine adsorption. Moreover, complex 9 shows a better iodine adsorption and encapsulates 166.55 mg g⁻¹ iodine in the vapor phase at 60 °C, which corresponded to 0.38 molecules of iodine per formula unit.     

A discrete electromagnetism-like mechanism for parallel machine scheduling under a grade of service provision

We consider the problem of minimising total weighted tardiness on identical parallel machines with grade of service eligibility. Due to the essential complexity of the problem, we apply an electromagnetism-like mechanism (EM), which is a novel metaheuristic, to solve the problem. In the proposed EM, the particle is redesigned to represent a valid assignment of jobs to machines. A distance measure between particles, called ‘1A2B’ distance, is proposed by the concept of a number guessing game. Then, the new attraction and repulsion operators are developed to move a particle to the new particle. To verify the proposed EM, computational experiments are conducted to make a comparison with a recent genetic algorithm (GA). The results show that the proposed EM has a good performance and outperforms the GA for the considered problem.     

Genipin-crosslinked gelatin scaffolds for articular cartilage tissue engineering with a novel crosslinking method

A novel crosslinking method with directly crosslinking the gelatin gel, being cut to a disc of chosen size beforehand, for the fabrication of porous gelatin scaffold was proposed. This novel method of gel-crosslinking was compared with the traditional methods of mixing-crosslinking and scaffold-crosslinking. The structure of the scaffold fabricated by the gel-crosslinking method shows uniformly distributed and interconnected pores which can be much smaller than those made by the other two methods. All three methods have the last step as freeze-drying; nevertheless, freeze-drying once more will increase the uniformity of the structure and the interconnecting pores. Crosslinking of gelatin was carried out at room temperature with glutaraldehyde (GTA) or genipin (GP). In vitro cell culture of Wistar rat's joint chondrocytes demonstrates that the GTA-crosslinked scaffold is much worse than the GP-crosslinked one; a tissue containing collagen and glycosaminoglycan was produced in the GP-crosslinked scaffold in just 9 days after cell seeding, and a tissue with a cell distribution resembling that of the native cartilage was developed after 30 day cell culture. It was concluded that the novel method is feasible for application in articular cartilage tissue engineering.