An effective RGB color selection for complex 3D object structure in scene graph systems

The goal of this project is to develop a complete, fully detailed 3D interactive model of the human body and systems in the human body, and allow the user to interacts in 3D with all the elements of that system, to teach students about human anatomy. Some organs, which contain a lot of details about a particular anatomy, need to be accurately and fully described in minute detail, such as the brain, lungs, liver and heart. These organs are need have all the detailed descriptions of the medical information needed to learn how to do surgery on them, and should allow the user to add careful and precise marking to indicate the operative landmarks on the surgery location. Adding so many different items of information is challenging when the area to which the information needs to be attached is very detailed and overlaps with all kinds of other medical information related to the area. Existing methods to tag areas was not allowing us sufficient locations to attach the information to. Our solution combines a variety of tagging methods, which use the marking method by selecting the RGB color area that is drawn in the texture, on the complex 3D object structure. Then, it relies on those RGB color codes to tag IDs and create relational tables that store the related information about the specific areas of the anatomy. With this method of marking, it is possible to use the entire set of color values (R, G, B) to identify a set of anatomic regions, and this also makes it possible to define multiple overlapping regions

A RESEARCH ON MULTI-OBJECTIVE OPTIMIZATION OF THE GRINDING PROCESS USING SEGMENTED GRINDING WHEEL BY TAGUCHI-DEAR METHOD

In this study, the mutil-objective optimization was applied for the surface grinding process of SAE420 steel. The aluminum oxide grinding wheels that were grooved by 15 grooves, 18 grooves, and 20 grooves were used in the experimental process. The Taguchi method was applied to design the experimental matrix. Four input parameters that were chosen for each experiment were the number of grooves in cylinder surface of grinding wheel, workpiece velocity, feed rate, and cutting depth. Four output parameters that were measured for each experimental were the machining surface roughness, the system vibrations in the three directions (X, Y, Z). The DEAR technique was applied to determine the values of the input parameters to obtaine the minimum values of machining surface roughness and vibrations in three directions. By using this technique, the optimum values of grinding wheel groove number, workpiece velocity, feed-rate, cutting depth were 18 grooves, 15 m/min, 2 mm/stroke, and 0.005 mm, respectively. The verified experimental was performed by using the optimum values of input parameters. The validation results of surface roughness and vibrations in X, Y, Z directions were 0.826 (µm), 0.531 (µm), 0.549 (µm), and 0. 646 (µm), respectively. These results were great improved in comparing to the normal experimental results. Taguchi method and DEAR technique can be applied to improve the quality of grinding surface and reduce the vibrations of the technology system to restrain the increasing of the cutting forces in the grinding process. Finally, the research direction was also proposed in this stud

A Novel Wideband Circularly Polarized Antenna for RF Energy Harvesting in Wireless Sensor Nodes

A novel wideband circularly polarized antenna array using sequential rotation feeding network is presented in this paper. The proposed antenna array has a relative bandwidth of 38.7% at frequencies from 5.05 GHz to 7.45 GHz with a highest gain of 12 dBi at 6 GHz. A corresponding left-handed metamaterial is designed in order to increase antenna gain without significantly affecting its polarization characteristics. The wideband circularly polarized antenna with 2.4 GHz of bandwidth is a promising solution for wireless communication system such as tracking or wireless energy harvesting from Wi-Fi signal based on IEEE 802.11ac standard or future 5G cellular. A potential application of this antenna as a receiving antenna for RF-DC device to obtain DC power for a wireless sensor node from Wi-Fi signal is shown

Liquid pumping and mixing by PZT synthetic jet

In this paper, a PZT synthetic jet that can function as both an efficient pumping and mixing device is developed. Compare with the conventional design where the practice of controlling the internal flow is undertaken by microvalves structure, this approach promotes the durability and allows the device to work with different liquids at high Reynold number without losing of backflow from the diffuser, therefore provides efficient mixing. The pumping performance is applicable for commercialized counterparts while the homogeneous medium was obtained at downstream in the experiments, which was further confirmed by simulation. Notably, the chaotic mixing feature of the device is also applicable for immiscible liquids with the micro-droplet formation result at the outlet

Extract and fraction of cashew nut testa ameliorate the hyperglycemic mice induced by Streptozotocin and high-fat diet

Drug strategy is a standard method for treating type 2 diabetes mellitus (T2D), a non-communicable disease with increasing prevalence, which may cause side effects. Therefore, natural compounds with limited adverse effects have come back into vogue for treating T2D. This study aims to evaluate the effects on rehabilitating hyperglycemic mice of cashew nut testa (husk) extract and fraction known as potential bio-substances for improvement in T2D. First, the hyperglycemic mice were induced with a high-fat diet (HFD) for 4 weeks and then were injected with streptozotocin (STZ, dozen for injection was 40 mg/kg/week) for 2 weeks. Next, the confirmed hyperglycemic mice were treated with pioglitazone (HG+PG group), total extract (HG+TE group), and saponin-rich fraction (HG+SRF group) for 3 weeks. Then, the evaluation was based on body mass; blood glucose (BG) level; BG tolerance, lipid profile, pancreatic histology and the expression IRS-1 in the pancreas. The results showed that body mass and BG level significantly increased in hyperglycemic mice. After substance treatment, there was no change in body mass in TE and SRF groups. However, BG level of HG+TE group mice significantly decreased compared to hyperglycemic mice and only BG tolerance of HG+SRF group was improved. Besides, HG+TE and HG+SRF groups modulated the triglyceride, HDL and LDL close to those expressed in normal mice. In addition, histological images of the pancreas revealed the restoration in both HG+TE and HG+SRF groups. Simultaneously, the IRS-1 expression in HG+TE group pancreas was restored to its expression in normal mice. These results demonstrate that the TE and SRF of cashew nut testa could ameliorate BG, lipid profile and pancreatic IRS-1 expression and restore the damaged pancreas and islets in hyperglycemic mice

Natural Radioactivity in Commonly Building Materials Used in Vietnam - 11255

ABSTRACT Naturally occurring radionuclides in building materials contribute to external and internal exposure and that is necessary to be investigated. In the research, 213 samples of 11 different kinds of commonly used structural and covering building materials were collected from housing and other building construction sites and from suppliers in Vietnam to measure the natural radioactivity of Ra-226, Th-232 and K-40. The measurements were carried out using low background gamma-ray spectrometry with HPGe detector. The specific activities of the different building materials varied from 0.18 -395.28, 0.10 -266.52 and 0.76 -2006.78 Bq/kg with the average values of 52.09, 55.70 and 593.5 Bq/kg for Ra-226, Th-232 and K-40, respectively. The obtained data were compared with the corresponding reported data of other countries. The activity concentration index and the annual effective dose were evaluated to assess the potential radiological hazard associated with these building materials. The results showed that the enhanced concentration values were sometimes felling into granite tiles, especially imported granite tiles. These obtained data aimed to enlarge the database on natural radioactivity in commonly building materials used in Vietnam and to support technical aspects in hazard exposure reduction

Study on the effect of carbon black, carbon nanotube on the properties of rubber blend acrylonitrile butadiene rubber (NBR)/polyvinyl chloride (PVC)

The effects of carbon nanotube (CNT) in combination with carbon black (CB) on the properties of acrylonitrile butadiene rubber (NBR)/polyvinyl chloride (PVC) (70/30) were investigated. The results reveal that the maximal tensile strength of the rubber blend was obtained by the fillers ratio of CB:CNT = 39:1. At this filler ratio, the thermal stability and heat conductivity of the rubber blend were also significantly improved. The analysis of FE-SEM images and DMA diagram indicate that the dispersion of filler as well as the interaction between fillers and rubber matrix was improved by the incorporation of CNT. Keywords. NBR/PVC blends, carbon nanotube (CNT), carbon black (CB), nanocomposites

Spatiotemporal evolution of SARS-CoV-2 Alpha and Delta variants during large nationwide outbreak of COVID-19, Vietnam, 2021

We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions

Inverse association of highly chlorinated dioxin congeners in maternal breast milk with dehydroepiandrosterone levels in three-year-old Vietnamese children

This study aims to evaluate the endocrine-disrupting effect of dioxin congeners on adrenal steroid hormones in mother-child pairs. In our previous study, we found that cortisol and cortisone levels were higher in the blood and the saliva of mothers living in a dioxin hotspot area than in mothers from a non-exposed region in Vietnam. In this follow-up study, we determined the salivary steroid hormone levels in 49 and 55 three-year-old children of these mothers in the hotspot and non-exposed region, respectively. Steroid hormones were determined by liquid chromatography-tandem mass spectrometry, and dioxin in the maternal breast milk was determined by gas chromatography-mass spectrometry. Dioxin levels in the breast milk of mothers from the hotspot (median total toxic equivalents polychlorinated dibenzodioxins/polychlorinated dibenzofurans; (TEQ PCDD/Fs) of 11. pg/g lipid) were three to four times higher than those of mothers in the non-exposed region (median TEQ PCDD/Fs of 3.07. pg/g lipid). Salivary dehydroepiandrosterone (DHEA) levels in children were found to be significantly lower in the hotspot than in the non-exposed region, while cortisol and cortisone levels were not different between the two regions. Highly chlorinated dioxin congeners, such as octacholorodibenzodioxin (OCDD), 1,2,3,4,6,7,8-heptacholorodibenzodioxin (HpCDD) and 1,2,3,4 (or 6), 7,8-hexachlorodibenzodioxin Hx(CDD), showed stronger inverse associations with the children\u27s salivary DHEA than other lowly chlorinated dioxin congeners. Glucocorticoid levels in the mothers exhibited a significantly positive correlation with OCDD and HpCDD/F (polychlorinated dibenzofurans). In conclusion, highly chlorinated dioxin congeners are more strongly correlated with endocrine-disrupting effects on adrenal hormones, resulting in high cortisol levels in the mothers and low DHEA levels in their three-year-old children. © 2016 Elsevier B.V.Embargo Period 24 month

Low birth weight of Vietnamese infants is related to their mother’s dioxin and glucocorticoid levels

We aimed to determine the relationship between dioxin congeners in maternal breast milk and maternal glucocorticoid levels with newborn birth weight after nearly 45 years of use of herbicides in the Vietnam War. The study subjects comprised 58 mother–infant pairs in a region with high dioxin levels in the soil (hotspot) and 62 pairs from a control region. Dioxin levels in maternal breast milk were measured by HRGC-HRMS. Salivary glucocorticoid levels were determined by LC-MS/MS. Dioxin congener levels in mothers from the hotspot were found to be two to fivefold higher than those in mothers from the control region. Birth weight was inversely correlated with 2,3,7,8-TeCDD and 2,3,4,7,8-PeCDF congener levels. The rate of newborns whose birth weight was less than 2500 g was threefold higher in the hotspot (12 %) than in the control region (4 %). Salivary glucocorticoid levels in mothers with low birth weight infants were significantly higher than those in the normal birth weight group. Low birth weight of Vietnamese newborns in a hotspot for dioxin levels is related to some dioxin congener levels and high glucocorticoid levels in mothers. This finding in mother–infant pairs suggests that excess maternal glucocorticoid levels are related to dioxin burden and they result in low birth weight. © 2016 Springer-Verlag Berlin HeidelbergEmbargo Period 12 month