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Background: The under-representation of Vietnamese ethnic groups in existing genetic databases and studies have undermined our understanding of the genetic variations and associated traits or diseases in the population. Cost and technology limitations remain the challenges in performing large-scale genome sequencing projects in Vietnam and many developing countries. Non-invasive prenatal testing (NIPT) data offers an alternative untapped resource to study genetic variations in the Vietnamese population. Results: We analyzed the low-coverage genomes of 2,683 pregnant Vietnamese women using their NIPT data and identified a comprehensive set of 8,054,515 single-nucleotide polymorphisms, among which 8.2% were new to the Vietnamese population. Our study also revealed 24,487 disease-associated genetic variants and their allele frequency distribution, especially five pathogenic variants for prevalent genetic disorders in Vietnam. We also observed major discrepancies in the allele frequency distribution of disease-associated genetic variants between the Vietnamese and other populations, thus highlighting a need for genome-wide association studies dedicated to the Vietnamese population. Conclusions: We have demonstrated a successful analysis of NIPT data to reconstruct the Vietnamese genetic profiles. This application provides a powerful yet cost-effective approach for large-scale population genetic studies.

Gear is one of the most common and important components in machinery. Evaluation on durability of gears plays crucial role in the assessment of the whole system reliability and service life. For other parts like shafts, the gears also act as loads. Therefore, dimensions and weight of the gears should be reduced as much as possible, contributing the size and weight reduction of the whole systems, which is essential to be cost-effectiveness. The current research focuses on optimal weight design problem of spur gears, such that the weight is minimized under the constraints taken from working conditions. The weight is a function of six variables, i.e. face width, shaft diameter of pinion, shaft diameter of gear, number of teeth on pinion, module and hardness. Constraints are derived based on AGMA standard and engineering handbooks, including the bending strength, the surface fatigue strength, the interference condition, the condition for uniform load distribution, the torsional strength of shaft on pinion and gear, and the center distance. The set of optimum design variables is determined by the heuristic algorithm Grey Wolf Optimizer (GWO). The accuracy and efficiency of the GWO in the optimal weight design problem of spur gears are assessed based on comparison with other popular methods, such as Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Simulated Annealing (SA). It is noted that in previous works, some of the constraints are still violated. Therefore, a penalty term is taken into the objective function, such that any set of design variables that violates constraints will be considered as ``unfit'' by the algorithm. It is demonstrated that using the proposed approach by current work, the optimal weight and the corresponding set of design variable are very close to reference data. Yet the advantage of the proposed approach is exhibited in the fact that all of the constraints are satisfied.

We observed 18 groups of golden-cheeked gibbons (Nomascus gabriellae) in the secondary lowland forest in Cat Tien National Park from January 2004 to December 2005 to obtain information about the social organization of this little-studied species, in an area where the population is recovering through increased protection and forest regeneration. DNA from faecal samples of 10 infants and juveniles identified 1 case of extrapair paternity. DNA from faecal samples of 18 adults from three communities revealed the majority of adults sampled of both sexes to be related to adults in neighbouring territories. Overall, the indications are that in this empty habitat, gibbons appear to be able to establish territories adjacent to those of their kin.