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Urbanization is one of the important features of socio-economic development and it has a major impact on the value of ecosystem services (ESV). This study aims to quantify ESV for the entire country of Vietnam with the research unit being 6 socio-economic regions. This can be considered the first study in Vietnam to quantify the ESV for the entire country. The study calculated the annual urban land growth index (AI) and the annual urban land expansion rate (AER) to determine the urbanization status in the six study areas. The study collected input data from JAXA for four years: 1990, 2000, 2010, and 2020. Research results show that urban land area tended to increase and forest land area decreased sharply. The AI and AER indicated that the period 2000–2010 was a period of rapid growth in Vietnam. Meanwhile, the ESV for all of Vietnam increased year by year. The period 2000–2010 witnessed a growth in ESV about 2.35 times higher than the period 1990–2000, and about 0.1 % lower than the period 2010–2020. Overall, MKD was the region showing strong growth in ESV from 1990 to 2020. Compared to that, NMR was the region with the largest decline in the 20 years from 1990 to 2010, and CHR in the past 10 years. This research contributes to enriching reference sources for Vietnamese and world researchers to have a broader view of ESV as well as the annual urban growth rate in Vietnam from 1990 to 2020.

The prevalence of overweight and obesity among adolescents has been increasing worldwide and is a significant public health challenge. Obesity is linked to several non-communicable diseases. This study aimed to determine the prevalence of overweight and obesity based on three growth references and described physical activities and dietary patterns among sixth graders in Ho Chi Minh City (HCMC). From 2018 to 2020, a cross-sectional study was conducted on 1375 students from 16 junior high schools in HCMC. We applied Probability Proportional to Size sampling to select schools. Anthropometric measurements, pubertal status assessment, and diet and physical activity data were collected through Food Frequency and Physical Activity Questionnaires. The study revealed a high prevalence of overweight and obesity among grade 6 students, with ∼45%–56% of students classified as overweight or obese using various growth references. Moreover, most students did not meet the World Health Organization's physical activity and sedentary behavior recommendations. Most students spent <60 min/day on moderate to vigorous physical activity, and over 70% spent at least 120 min/day on sedentary activities during weekdays and weekends. The diet of the students was also imbalanced, with high intakes of protein, lipids, and carbohydrates and low consumption of fruits and vegetables. Nutritionists and policymakers should inform and encourage opportunities for healthier food and more daily activity for children, starting before the sixth-grade, so they can learn how to make healthier choices and change their behavior before they reach adolescence. [ABSTRACT FROM AUTHOR]

We report the first conductance measurements of [n]staffane (bicyclopentane) oligomers in single‐molecule junctions. Our studies reveal two quantum transport characteristics unique to staffanes that emerge from their strained bicyclic structure. First, though staffanes are composed of weakly conjugated C−C σ‐bonds, staffanes carry a shallower conductance decay value (β=0.84±0.02 n−1) than alkane chain analogs (β=0.96±0.03 n−1) when measured with the scanning tunneling microscopy break junction (STM‐BJ) technique. Staffanes are thus more conductive than other σ‐bonded organic backbones reported in the literature on a per atom basis. Density functional theory (DFT) calculations suggest staffane backbones are more effective conduits for charge transport because their significant bicyclic ring strain destabilizes the HOMO‐2 energy, aligning it more closely with the Fermi energy of gold electrodes as oligomer order increases. Second, the monostaffane is significantly lower conducting than expected. DFT calculations suggest that short monostaffanes sterically enforce insulating gauche interelectrode orientations over syn orientations; these steric effects are alleviated in longer staffanes. Moreover, we find that [2‐5]staffane wires may accommodate axial mechanical strain by “rod‐bending”. These findings show for the first time how bicyclic ring strain can enhance charge transmission in saturated molecular wires. These studies showcase the STM‐BJ technique as a valuable tool for uncovering the stereoelectronic proclivities of molecules at material interfaces. [ABSTRACT FROM AUTHOR]

Gonorrhea is a sexually transmitted infection caused by Neisseria gonorrhoeae; global incidence is [approximately equal to]80 million cases/year (2,2). To treat uncomplicated gonorrhea, the World Health Organization recommends dual therapy [...]

Dexterous magnetic manipulation of ferromagnetic objects is well established, with three to six degrees of freedom possible depending on object geometry.sup.1. There are objects for which non-contact dexterous manipulation is desirable that do not contain an appreciable amount of ferromagnetic material but do contain electrically conductive material. Time-varying magnetic fields generate eddy currents in conductive materials.sup.2-4, with resulting forces and torques due to the interaction of the eddy currents with the magnetic field. This phenomenon has previously been used to induce drag to reduce the motion of objects as they pass through a static field.sup.5-8, or to apply force on an object in a single direction using a dynamic field.sup.9-11, but has not been used to perform the type of dexterous manipulation of conductive objects that has been demonstrated with ferromagnetic objects. Here we show that manipulation, with six degrees of freedom, of conductive objects is possible by using multiple rotating magnetic dipole fields. Using dimensional analysis.sup.12, combined with multiphysics numerical simulations and experimental verification, we characterize the forces and torques generated on a conductive sphere in a rotating magnetic dipole field. With the resulting model, we perform dexterous manipulation in simulations and physical experiments. Time-varying magnetic fields can be used to manipulate the position and orientation of conductive non-magnetic objects., Author(s): Lan N. Pham [sup.1] , Griffin F. Tabor [sup.2] , Ashkan Pourkand [sup.2] , Jacob L. B. Aman [sup.3] , Tucker Hermans [sup.2] [sup.4] , Jake J. Abbott [sup.1] [...]

Background Body composition parameters are linked to cardio-metabolic risk. However, high-quality reference values of body composition are scarce, particularly in Asian population. The aim of study was to construct sex- and age-specific normative reference values of body composition for the Vietnamese population. Methods This study was designed as a cross-sectional investigation that involved 2700 women and 1459 men aged between 20 and 90 (average 48, SD 15) who were participants in the population-based Vietnam Osteoporosis Study. Whole-body composition parameters (e.g., fat mass and lean mass) and site-specific (head, arms, trunk, and legs) parameters were measured by dual-energy X-ray absorptiometry (Hologic Horizon). Reference curves for each parameter and anatomical site were constructed using the Generalized Additive Model for Location Scale and Shape modeling technique. Results Overall, 8% of women and 11% of men were classified as obese (body mass index [greater than or equal to] 27.5 kg/m.sup.2). Most fat mass was deposited at the trunk (~50%), followed by the leg (~33%). Women had ~10% more body fat (relative to body weight) than men. However, whole-body lean mass was higher in men than women, with the average difference being ~13 kg. Moreover, men had more bone mineral content than women (2110 vs. 1600 g). We also provided a comparison of age-related changes in body composition parameters between Vietnamese and US Whites. Conclusion These data provide gender- and age-specific reference values of body composition parameters for Vietnamese population. These normative values provide health professionals and the public with a resource for interpretation of body composition data., Author(s): Huy G. Nguyen [sup.1] [sup.2] [sup.3] , Nghi V. Le [sup.1] [sup.2] , Khang H. Nguyen-Duong [sup.1] [sup.2] , Lan T. Ho-Pham [sup.1] [sup.2] , Tuan V. Nguyen [sup.3] [...]

This study is conducted to provide a systematic review of the existing publications regarding the usage of user-generated video (UGV) for travel planning to present insights, highlight the state-of-art context and suggest potential future research trends in the field. A systematic review process is carried out, including synthesis, classification, and analysis to explore the development, characteristics, theoretical and conceptual models, as well as measurements associated with the use of UGV for travel planning. A total of 52 articles published between 2009 and 2022 are collected and categorised into five categories, including the role of platforms that contain user-generated content (UGC), the characteristic related to UGV/the source characteristic, the characteristic of users (travellers), users (travellers) response, research framework development. Thematic analysis of research categories/themes provides theoretical discourse and insights to address backlog research problems in this field. This study can be viewed as the first systematic review regarding the use of UGV for travel planning. In addition, the methods are used to describe how the research topic is formulated. Furthermore, the usefulness of the qualitative methodology allows the authors to thoroughly analyse the theoretical context of research using UGV for travel planning. [ABSTRACT FROM AUTHOR]

This study partially replaced the clay with sewer sludge (SS) and rice husk (RH-SS) to make fired bricks. The brick samples were examed in terms of shrinkage, water absorption, and compressive strength. Besides, they were analyzed via XRD and metal extraction to determine the heavy metal residuals in the products. The results showed that it was possible to fabricate fired bricks using sewer sludge or rice husk-blended sludge with up to 30% by weight. These brick samples complied with the technical standard for clay brick production, in which the compressive strength was more than 7.5 MPa, water absorption was from 11–16%, and the linear shrinkage was all less than 5%. The rice husk addition helped mitigate the heavy metal residuals in the bricks and leaching liquid, in which all the values were lower than the US-EPA maximum concentration of contaminants for toxicity characteristics. Implications: Previous studies have proved the possibility of mixing sewage sludge from different origins (sewage sludge, river sediment, canal sediment, sewer sediment, etc.) with clay and some wastes to make bricks. In which, mostof the studies used sewage sludge from wastewater treatment plants, very fewdealt with lake/river or sewer sediment. This study shall be the first to study the possibility of employing sewer sediments with the addition of rice husk powder to achieve two targets, including (1) the reuse of biowaste and sludge for brick fabrication and (2) the reduction of heavy metals in final calcined bricks. Different ratios of the rice-husk blended sewer sludge (RH-SS) – clay mixture shall be tested to find the optimized compositions. The results showed that it was possible to fabricate fired bricks using sewer sludge or rice husk-blended sludge with up to 30% by weight, which meant reduce 30% of clay in the brick production. The final products were proved to meet the quality standard in terms of compressive strength (more than 10 MPa), water absorption(from 11–16%), and the linear shrinkage (less than 5%). Larger scale of this study can be an evident to recommend for policy change in the waste reuse in construction field. [ABSTRACT FROM AUTHOR]