To determine the number and distribution of exposures among workers exposed to silica dust in Vietnam, a cross-sectional study was conducted of the provincial Preventive Medicine Centers (PMCs) of 61 provinces, and data were collected from medical centers (MCs) of the Ministries of Construction, Industry, and Transportation. The PMC survey identified 112,956 exposed workers in 31 provinces. Ministry data identified 240,744 exposed workers. Quang Ninh province, with 50,000-70,000, had the highest concentration. These estimates provide a range of 40,000-350,000 exposed workers, supporting the development of a validated registry of silica-exposed workers, essential to the development of a program for silicosis prevention in Vietnam.

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The transparent conductive property based on Ag-doped delafossite nanomaterials are attractive for optical sensing applications due to their good electrical conductivity, good optical transparent and high temperature coefficient of resistance. Several delafossite nanomaterials and Ag-doped nanomaterials have been reported, however, Ag-doped delafossite nanomaterials have not been explored, especially regarding the electrical property with high temperature coefficient of resistance. In this study, Ag-doped delafossite CuAlxOy thin films were deposited by co-sputtering techniques. The electrical properties were carried out on a 4-point prober. The optical properties were characterized on an UV-VIS spectrometer. The results on CuAlxOy doped Ag thin films showed that CuAlxOy doped Ag can be hardly applied for transparent conductive layers. However, these films exhibited relatively high temperature coefficient of resistance of about 3%/K, thus being suitable for applications in microbolometers.

This paper describes the egg-laying behavior and reproduction capacity of Anisopteromalus calandrae in laboratory conditions. Anisopteromalus calandrae lay eggs only on the Lasioderma serricorne larvae hiden inside of grains or nests. The maximum lifespan of A. calandrae females was 32 days when they were kept with of aqua feed flour plus honey (30%) and infested with larvae of Lasioderma serricorne. One female laid 71.13 ± 4.24 eggs. The eggs were laid mostly (81.95%) during the first half of the lifespan, with the peak of 7.40 eggs/day on the 9 th day. The females usually lay one egg/host larva, but sometimes they lay 2-5 eggs/host larva. They prefer to lay eggs on the 4 th larval instar.Keywords: Anisopteromalus calandrae, Lasioderma serricorne, ectoparasitoid, egg-laying rhythm, mass rearing, insect pests, stored products.