T he rubber dam has been a useful adjunct in restorative dentistry for many years. With the advent of new techniques and dental materials that are moisture sensitive, rubber dam use has become more imperative. An example of one of these new techniques is the removal of caries using air abrasion. Because the aluminum oxide particles of the air abrasion technique can become a messy paste in the o...

While the era of dam building is largely over in the United States, globally dams are still being proposed and constructed. The articles in this special issue consider many aspects and impacts of dams around the world. This paper examines dam removal and the measurement of the impacts of dams on local community property values. Valuable lessons may be found. In the United States, hundreds of sm...

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...

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.

Lake Oroville is a large artificial lake created by the construction of a 235-mhigh earth dam on the Feather River, California, near the city of Oroville. Its storage capacity is about 4.4 × 109 m 3, and its maximum depth is about 200 m. There was no significant increase in seismic activity in the lake region following impoundment of the dam late in 1967 until the occurrence of many small seism...

The fresh water reservoirs are one of the main power resources of Pakistan. These water reservoirs are in the form of Tarbela Dam, Mangla Dam, Bhasha Dam, Warsak Dam etc.[1]. To estimate the current power capability of the Dams, the statistical information about the water in the dam has to be clear. For the purpose of water management monthly or yearly survey of the dams required. One of the im...

Many Neisseriaceae do not exhibit Dam methyltransferase activity and, instead of the dam gene, possess drg (dam replacing gene) inserted in the leuS/dam locus. The drg locus in Neisseria gonorrhoeae FA1090 has a lower GC-pairs content (40.5%) compared to the whole genome of N. gonorrhoeae FA1090 (52%). The gonococcal drg gene encodes a DNA endonuclease Drg, with GmeATC specificity. Disruption o...

Dams have been a fundamental part of the U.S. national agenda over the past two hundred years. Recently, however, dam removal has emerged as a strategy for addressing aging, obsolete infrastructure and more than 1,100 dams have been removed since the 1970s. However, only 130 of these removals had any ecological or geomorphic assessments, and fewer than half of those included before- and after-r...

The DNA-[N 6-adenine]-methyltransferase (Dam MTase) of phage T4 catalyzes methyl group transfer from S-adenosyl-l-methionine (AdoMet) to the N6-position of adenine in the palindromic sequence, GATC. We have used a gel shift assay to monitor complex formation between T4 Dam and various synthetic duplex oligonucleotides, either native or modified/defective. The results are summarized as follows. ...