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Arsenic, an environmental pollutant, is present in minute but invariable amounts in food, drinking water and ambient air. Izmir is founded on a land of long extinct volcanoes, with vast areas of lava ground suitable for agriculture. It is located at close vicinity to high thermal activity, e.g., hot springs and thermal baths. In the present study, total arsenic level in breast milk was assessed in randomly chosen 35 lactating women of different socioeconomic levels who live downtown in Izmir and in milk of 36 cows grazing on shoulder grass of highways with heavy traffic. Total arsenic was assessed on an atomic absorption spectrophotometer (AA-680 Shimadzu). Mean (± SEM) arsenic was found to be 4.219 ± 0.079 µg L-1 in breast milk, and 4.932 ± 0.38 µg L-1 in cow's milk. Conclusion: in Izmir, arsenic contamination of breast milk was not found so as to be considered noxious for suckling infants, whereas was found relatively higher in cow's milk. It would be prudent to remember breast and cow's milk arsenic contamination in breast fed or milk fed babies living in areas with higher thermal activity or in regions where ground water is with high arsenic content.  相似文献   
2.
Bisphenol A (BPA), diethylhexyl phthalate (DEHP) and pentabrominated diphenyl ether 99 (PBDE 99) are environmental toxicants belonging to the endocrine disrupting compounds (EDCs). They exert adverse effects on the various physiological systems, especially the reproductive system of humans and animals. The aim of this study was to investigate the effects of BPA, DEHP and PBDE 99 on progesterone (P4) synthesis in cultured bovine luteal cells. The bovine luteal cells isolated from the mid-luteal corpora lutea were exposed to different concentrations of BPA (1, 3, 10 and 30 µM), DEHP (1, 3, 10 and 30 µM) and PBDE 99 (0.1, 0.3, 1 and 3 µM) in a serum-free culture media for 48 and 96 hr. At 48 hr, the P4 level in the luteal cells decreased after treatment with all concentrations of BPA; 3, 10 and 30 µM of DEHP; and 3 µM of PBDE 99 compared to the control (p < .05). Treatment of cells with 3–30 µM of BPA, 1–30 µM of DEHP and 1–3 µM of PBDE 99 for 96 hr resulted in reduction in P4 synthesis (p < .05). However, lower concentrations of PBDE 99 (0.1 and 0.3 µM) increased P4 levels at 48 and 96 hr. Synthesis of P4 was lower at 96 hr compared to the 48 hr in the groups treated with BPA (30 µM), DEHP (1–30 µM), PBDE 99 (0.3–3 µM) and control group. Our results showed that BPA, DEHP and PBDE 99 are able to alter luteal steroidogenesis in bovine cells and can disrupt hormonal balance in the ovary. However, it is necessary to evaluate the exact mechanism underlying these effects in future studies.  相似文献   
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This study was conducted to assess crop water stress index (CWSI) of bermudagrass used widely on the recreational sites of the Mediterranean Region and to study the possibilities of utilization of infrared thermometry to schedule irrigation of bermudagrass. Four different irrigation treatments were examined: 100% (I1), 75% (I2), 50% (I3), and 25% (I4) of the evaporation measured in a Class A pan. In addition, a non-irrigated treatment was set up to determine CWSI values. The status of soil water content and pressure was monitored using a neutron probe and tensiometers. Meanwhile the canopy temperature of bermudagrass was measured with the infrared thermometry. The empirical method was used to compute the CWSI values. In this study, the visual quality of bermudagrass was monitored seasonally using a color scale. The best visual quality was obtained from I1 and I2 treatments. Average seasonal CWSI values were determined as 0.086, 0.102, 0.165, and 0.394 for I1, I2, I3, and I4 irrigation treatments, respectively, and 0.899 for non-irrigated plot. An empirical non-linear equation, Qave=1+⌊6[1+(4.853 CWSIave)2.27]−0.559Qave=1+6[1+(4.853 CWSIave)2.27]0.559, was deduced by fitting to measured data to find a relation between quality and average seasonal CWSI values. It was concluded that the CWSI could be used as a criterion for irrigation timing of bermudagrass. An acceptable color quality could be sustained seasonally if the CWSI value can be kept about 0.10.  相似文献   
4.
The purpose of this research was to examine the effects of different irrigation levels on evapotranspiration (ET) and quality characteristics of golf-course turfgrasses grown under Mediterranean climatic conditions and to determine the most economical irrigation level which would provide an acceptable turfgrass quality level. Four different irrigation treatments were examined: 100% (S1), 88% (S2), 75% (S3), and 50% (S4) of the evaporation measured in the Class A Pan. Treatment S2 represented the existing irrigation level practiced by golf course management. The best color quality during the experimental period was obtained from the S3 irrigation treatment, followed by S2. Results regarding the ground cover percentage and root weights in the S2 and S3 treatments were better than S1 and S4. It was concluded that Class A Pan could be used to schedule turfgrass irrigation and 75% of evaporation from Class A Pan would be enough for irrigation. Additionally, it was found that 15% of irrigation water could be conserved compared with the current irrigation schedule (S2), practiced by the owner.  相似文献   
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