Evaluation of groundwater quality in a rural community in North Central of Nigeria

Evaluation of water quality of nine boreholes and three open hand-dug wells in a rural community in North Central Nigeria revealed relative abundance of cations Na > k > Ca >Mg> Zn > Pb and anions Cl− > PO4 2 − > SO4 2 − > NO3− in the boreholes and cations Ca>Na>K>Mg>Pb and anions NO3− > PO4 2 − > SO4 2 − > Cl− in the wells. The major contaminants exceeding SON and WHO permissible limits were NO3−, Mg, TH, pH and Mg, Pb, TH, pH and DO in the wells and boreholes, respectively. They are attributable to anthropogenic sources such as domestic waste water and poor waste disposal and natural sources such as mineral dissolution from clayey aquifer which made the acidic groundwater unsuitable for consumption unless they are appropriately treated. Correlation studies revealed existence of three major mineral groups in the aquifer Ca-Fe group, Na-Mg group, Zn-K group, as well as a minor group Pb-group, and they determine the chemical composition of the groundwater and the ionic exchange between the groundwater and mineral-bearing clayey aquifer. In order to curb microbial contamination by Enterobacter aerogenes and Escherichia coli, it is recommended that proper latrines and drainages be provided while domesticated animals should be restricted from boreholes and well. Further, treatment with water guard and pur purifier is recommended

TRPA1 mediates sensation of the rate of temperature change in Drosophila larvae

Avoidance of noxious ambient heat is crucial for survival. A well-known phenomenon is that animals are sensitive to the rate of temperature change. However, the cellular and molecular underpinnings through which animals sense and respond much more vigorously to fast temperature changes are unknown. Using Drosophila larvae, we found that nociceptive rolling behavior was triggered at lower temperatures and at higher frequencies when the temperature increased rapidly. We identified neurons in the brain that were sensitive to the speed of the temperature increase rather than just to the absolute temperature. These cellular and behavioral responses depended on the TRPA1 channel, whose activity responded to the rate of temperature increase. We propose that larvae use low-threshold sensors in the brain to monitor rapid temperature increases as a protective alert signal to trigger rolling behaviors, allowing fast escape before the temperature of the brain rises to dangerous levels