In a study of regional variations in cardiovascular mortality in Great Britain during 1969-73 based on 253 towns the possible contributions of drinking water quality, climate, air pollution, blood groups, and socioeconomic factors were evaluated. A twofold range in mortality from stroke and ischaemic heart disease was apparent, the highest mortality being in the west of Scotland and the lowest ...

UNLABELLED The longevity and durability of composite resins are influenced by the actions of water, saliva, drinks, food and features of the oral environment. OBJECTIVE The aim of this study was to evaluate the effect of mouthwashes containing alcohol on the surface hardness, sorption and solubility of composite resins. METHODS Disc-shaped specimens were prepared with two composite resins Z...

there are 3700 wells in tehran city, of which 850 are deep wells. to determine tehran ground water quality, as a pretest we selected 102 wells by simple random sampling; water analyses were made according to the latest edition (1985) of the standard methods. comparisons of the obtained results with who standards show that only 0.98% of the samples go beyond the maximum desirable concentration o...

Polypropylene/wood flour composites were melting compounded in an internal mixer at 190°C and 60 rpm rotor speed and then samples were fabricated by injection molding. Effects wood flour content on the physical properties of composites was investigated. For this purpose, hardness, water absorption and thickness swelling of samples was determined at different levels of wood flour content. The re...

To explain the associations of water hardness and air temperature with area differences in ischaemic heart disease mortality, samples of tap water were obtained from homes in 61 county boroughs in England and Wales, and the concentration of calcium and 12 other elements was estimated. Multiple regressions were calculated with the death rates from various causes as dependent variables and with t...

background: in recent times, the decreasing groundwater reserves due to over-consumption of water resources and the unprecedented reduction of precipitation, during the past 1 decades, have resulted in a change in the volume and quality of water with time. the aim of this study was to determine the spatial and temporal variations of hardness and total dissolved solids in drinking water resource...

background: desalination plants have an important role in providing community drinking water. the increasing trend of water consumption and decrease of natural resources of fresh water make this role even more important. the aim of this study was to evaluate the quality of inlet and outlet water of desalination plants by reverse osmosis (ro) process in qeshm, iran and also to compare the qualit...

This study evaluated Knoop hardness, surface roughness and color alteration of artificial teeth for dentures after immersion in water, 1% sodium hypochlorite and an experimental solution of 2% Ricinus communis (RC). Thirty specimens of Vipi, Biolux and Trilux were analyzed. Tests of Knoop hardness, surface roughness and color alteration were conducted immediately after specimen preparation (T0)...