We compared the bioaccumulation of lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu), nickel (Ni) and iron (Fe) with antioxidant enzyme activity in tissues of the snails, Lymnaea natalensis, exposed to elements of two differently polluted dams. 45 snails were exposed to sediment and water collected from Wight Dam (reference) whilst another 45 snails were also exposed to sediment and water collect...

BACKGROUND The placement of rubber dam has the potential to alter the airflow through nasal and oral cavities. Pediatric dentist should be aware whether the use of a rubber dam affects the oxygen saturation (SpO2) in children. To assess the effect of rubber dam on arterial blood SpO2 in children of 6-12 years age. MATERIALS AND METHODS Totally, 60 ASA Class I patients of 6-12 years age, rando...

Deoxyadenosine methyltransferase (Dam) methylates the deoxyadenine residues in 5'-GATC-3' sequences and is important in many cellular processes in Escherichia coli. We performed a computational analysis of the entire E. coli genome and confirmed that GATC sequences are distributed unevenly in regulatory regions, which suggests that Dam might regulate gene transcription. To test this, a high-den...

The mismatch repair system of Escherichia coli K12 removes mispaired bases from DNA. Mismatch repair can occur on either strand of DNA if it lacks N6-methyladenines within 5'-GATC-3' sequences. In hemimethylated heteroduplexes, repair occurs preferentially on the unmethylated strand. If both strands are fully methylated, repair is inhibited. Mutant (dam-) strains of E. coli defective in the ade...

Safety control of concrete dams is required due to the potential great loss of life and property in case of dam failure. The purpose of this paper is to feed back the operational control loads for concrete dam displacement using the maximum entropy method. The proposed method is not aimed at a judgement about the safety conditions of the dam. When a strong trend-line effect is evident, the meth...

A total of 257 fishes from four families, Clariidae, Cichlidae, Cyprinidae and Schilbeidae were collected from three localities: the Sand River Dam, Swaziland; the Nylsvlei Nature Reserve, South Africa and the Vaal Dam and Vaal River Barrage, South Africa. Only fishes (n= 154) from Clariidae and Cichlidae were found to be infected with trypanosomes. A total of 221 Clarias gariepinus (Burchell 1...

Low-head dam impoundments modify local habitat and alter fish assemblages; however, to our knowledge, the pattern of how fish assemblages in the impoundments relate to local habitat, tributary position, and dam characteristics is still unclear. We used data collected in 62 impoundments created by low-head dams in headwater streams of the Qingyi River, China, to examine relationships between fis...

Paul C. Rizzo Associates, Inc. (RIZZO) has developed efficient computational tools to evaluate the liquefaction potential of earth embankment dams located within high risk seismic regions. Two relevant case histories are the Saluda Dam and the Santee Cooper East Dam Extension, both structures susceptible to liquefaction, and located in South Carolina. Saluda Dam presents liquefaction risks with...

Dam safety assessments rely on the skill and experience of dam engineers but such expertise is not always easily transferred to new staff or conveyed in written reports. Many old dams have outlived their creators and puzzle those that see them for the first time. Eliane Alves Portela and Joao Bento explain how expert system technology can help avoid this DAM construction started over 2000 years...

An infinite dam with compound Poisson inputs and a statedependent release rate is considered. For this dam, we solve Kolmogorov’s backward differential equation to obtain the Laplace transforms of the first exit times in terms of a certain positive kernel. This allows us to provide an explicit expression for the Laplace transform of the wet period for a finite dam.