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Background: Tea is one of most frequently consumed beverages in the world. Only in Iran, around 12000 tons of tea is annually used. Besides, green tea, which is made from Camellia sinensis leaves and buds, is very popular among people. Although teas have health benefits, since they may be much drunk, they may pose a threat to consumers’ health because of absorbing various ions in their leaves. Unfortunately, there are a limited number of studies on the health effects of green teas.Methods: It was a cross-sectional study performed in 2021. In this research, the concentrations of ions: fluoride (F), chloride (Cl), nitrate (NO3), sulfate (SO4), and phosphate (PO4) in the six bestselling green tea brands, both loose and bag, in Iran were detected by means of ion chromatography.Results: The highest amounts of F, Cl, NO3, SO4, and PO4 in the brands were found to be, respectively, in 0.27310, 0.62103, 0.83533, 1.28067, and 1.1037 mg/L. The concentrations of the ions in the both loose and bag tea samples were different significantly. Also, the content of F in the all samples was lower than those acceptable levels suggested by different organizations.Conclusion: It was found that the concentration of the ions was by far lower than those have been introduced as the standard levels. Nonetheless, the water used for tea infusion may contain high levels of these compounds and its volume drunk every day is also very important.

Simple Summary: This study was carried out to examine how different diets with vitamin solutions/vitamin premixes and plant oils (algae and fungi oils) affect the reproduction of Pangasius catfish broodstock, growth performance, and survival rates of fish larvae and fingerling. The experiment was designed as a factorial setup, with Pangasius catfish broodstock fed six different diets in triplicate groups of ten fish (three males and seven females) cultured in separate hapa nets in an the earthen pond for about two months. Results showed significant differences among the six tested diets. Diets containing 35% CP, supplemented with 0.6% vitamin solutions and 1.26% algal oil, produced the best results in terms of the highest growth performance, reproductive indices, and fingerling survival rates. These findings provide valuable information for Pangasius catfish farmers and the fish production industries in the Mekong Delta, Vietnam. This study evaluates the effect of different diets supplemented with vitamin solutions on Pangasius catfish broodstock reproduction, growth performances, and the survival rates of fish larvae and fingerling. The growth and reproductive performances of breeders fed with different test diets showed significant differences among the six tested diets (p < 0.05). The highest final body weight (FBW), weight gain (WG), daily weight gain (DWG), specific growth rate (SGR) of broodstock, and survival rate of Pangasius fingerlings were found in Treatment 5, which contained 0.6% H-OVN mixed with 12.6% algal oil, and Treatment 3, which contained 0.6% vitamin premix H-OVN. The average gonadosomatic index (GSI), relative fecundity index (RFI), fertilized eggs, hatching rates of eggs, and survival rate of fingerlings was 9.1 ± 2.8 (6.7–12.8%), 133,224 ± 39,090 (104,267–199,512 eggs/kg), 77.9 ± 22.2 (62.2–93.6%), and 45.3 ± 17.4 (22.0–66.3%), respectively. The findings of this study showed that the diet containing 35% CP contents supplemented with 0.6% vitamin premix H-OVN mixed with algal oils showed the highest results in terms of growth, reproductive performance indices, and survival rates of Pangasius catfish fingerlings. [ABSTRACT FROM AUTHOR]

This novel study on cement paste material was conducted with the aim of keeping up with the rapid development of urban construction and contributing to the continuous improvement of building materials to overcome environmental issues. In this study, several kinds of industrial waste were used to enhance the properties of cement paste for application in a marine environment with a tropical climate, such as in Vietnam. This study focuses on evaluating the properties of cement paste containing cement replacement combining 0–30% fly ash, 0–10% silica fume, and plasticizer accounting for 0.3% and 0.4% of the binder by mass. Water demand, chloride ion and sulfate ion permeability, and microstructural properties of the cement paste were determined by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscope (SEM) and they were investigated after 28 and 56 days. The test results show that an optimum mixture could be obtained with the use of 20% fly ash, 10% silica fume (replacing Portland cement), and 0.4% plasticizer. The application of such materials to sea dikes affected by a tropical climate (characterized by heat, humidity, salty seawater, many big storms, large waves, and strong tides) was investigated for four years on the Vietnamese coast. The test results indicate that fly ash and silica fume can improve the corrosion and abrasion resistance of concrete in coastal areas with a tropical climate, such as in Vietnam. [ABSTRACT FROM AUTHOR]

The current study was performed with an aim to investigate the performance of ecological revetments implemented on the bank of the Cuatien River in Vinh city, Vietnam. Based on the ecological, topographical, and hydrological conditions of the Cuatien River, the gabion and riprap models were introduced to investigate the effect of ecological revetment on the slope stability and ecological restoration characteristics. The effect of prevailing climatic indicators, such as temperature, precipitation, sunlight hours, and humidity were investigated to ascertain the characteristics of weather conditions on the subtropical area. On the surface soil layer of the gabion and riprap, the nutrient indicators of soil organic matter (SOM) and available nitrogen (AN) increased in the spring, summer, and winter, but decreased in autumn, and available phosphorus (AP) did not show an obvious change in the four seasons. The biomass growth rate of Vetiver grass on the gabion and riprap revetments was found to be the highest during the summer, at 15.11 and 17.32 g/month, respectively. The root system of Vetiver and other native plants could increase the cohesion of soil. After 6 and 12 months, the shear strength of the soil behind the gabion revetment increased by 59.6% and 162.9%, while the shear strength of the soil under the riprap also increased by 115.6% and 239.1%, respectively. The results also indicated that the gabion and riprap revetments could improve the river water purification effect and increase the ecological diversity in the region. In the current study, 26 floral and 9 faunal species were detected in the riprap revetment, whereas 14 floral and 5 faunal species were detected in the gabion revetment, respectively. Through high sequencing technology, the number of bacterial species in the present study was found to be 198, 332, and 351 in the water, gabion, and riprap samples, respectively. [ABSTRACT FROM AUTHOR]