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...

This study focuses on the shape optimization of concrete gravity dams considering dam– water–foundation interaction and nonlinear effects subject to earthquake. The concrete gravity dam is considered as a two–dimensional structure involving the geometry and material nonlinearity effects. For the description of the nonlinear behavior of concrete material under earthquake loads, the Drucker–Prage...

Risk analysis of gravity dam stability involves complicated uncertainty in many design parameters and measured data. Stability failure risk ratio described jointly by probability and possibility has deficiency in characterization of influence of fuzzy factors and representation of the likelihood of risk occurrence in practical engineering. In this article, credibility theory is applied into sta...

The effect of dam methylation on Tn5 transposition was investigated by analyses of mutations in the host (Escherichia coli) and the element. Wild-type elements transposed at a higher frequency and showed higher levels of transposase expression in a dam-host. Mutations were made in the promoter region of the transcript that codes for the transposase. Transposition and transposase levels from the...