The paper looked at the sources and levels of concentration of metal pollutants in Kubanni dam, Zaria, Nigeria. The main sources of data for the study were sediment from four different sections of the long profile of the dam. The samples were prepared in the laboratory according to standard methods and the instrumental Neutron Activation Analysis (INAA) technique was adopted in the analysis usi...

We examined in rat pups the relation between the decline of suckling and the emergence of independent ingestion, and the role of milk delivery conditional on nipple attachment in the maintenance of suckling. Fifteen-day-old litters were reared for either 5 or 10 days, and 20-day-old litters for 5 days by either a thelectomized (no nipples), ligated (nipples but no milk), or intact (nipples and ...

On 26 May 2003, intense rainfall from a series of thunderstorms in eastern North Carolina caused flooding that eventually destroyed the concrete dam in Hope Mills, draining Hope Mills Lake, and revealing a formerly submerged and buried structure that was identified as a timber crib dam. Inspection revealed these logs to be old-growth longleaf pines, which are now rare on the coastal plain lands...

Sand-cement emerged in the early twentieth century as an alternative binder in infrastructures that required a significant amount of concrete volume in order to reduce the costs associated with portland cement. This binder was first used in the United States in several dams before being applied in Camarasa Dam in Spain. Nearly a century after its construction, the dam exhibits degradation pheno...

Social relationships define an individual's position in its social network, which can influence the acquisition and spread of information and behavioural variants through the population. Thus, when nuisance behaviours spread through wildlife populations, identifying central individuals may provide valuable insights for problem-species management. We studied the effects of network position on Ca...

Four aquatic ecosystems (two rivers and two dams) situated in the western part of Bulgaria were investigated over a three years' period. The River Egulya and Petrohan dam are situated in mountainous regions at about 1000 m altitude, and are not influenced by any anthropogenic sources. Petrohan dam is a site for long-term ecosystem research as a part of Bulgarian long-term ecological research ne...

In Escherichia coli, the frequencies of IS50 and Tn5 transposition are greater in Dam- cells than in isogenic Dam+ cells. IS50 transposition is increased approximately 1,000-fold and Tn5 transposition frequencies are increased about 5- to 10-fold in the absence of Dam methylation. However, in cells that are deficient for both integration host factor (IHF) and Dam methylase, the transposition fr...

Abstract—The degradation of concrete due to various hygrochemo-mechanical actions is inevitable for the structures particularly built to store water. Therefore, it is essential to determine the material properties of dam-like structures due to ageing to predict the behavior of such structures after a certain age. The degraded material properties are calculated by introducing isotropic degradati...

T he m ain objective o f this study was the com parison o f changes in levels o f a-tocopherol and ascorbate in needles o f spruce trees w ith various degrees o f dam age at three low m ountain sites. The ascorbate content in needles o f spruce trees w ith various degrees o f dam age differs in the course o f seasons as well as in the absolute level. The antiox idant status was affected m ain­ ...

[1] Snow avalanches are a threat in many populated mountainous regions, and deflecting dams are often built to divert them away from people, and infrastructure, into less harmful areas. When an avalanche is deflected by a dam or wedge, it often generates rapid changes in the flow thickness and velocity, which can be modeled as an oblique shock wave. This paper reviews classical oblique shock th...