DNA helices must undergo openings in the form of localized strand separations in order to permit the onset of RNA synthesis or DNA synthesis. The selective control of such DNA helix openings at particular gene loci is the critical feature of gene regulation in prokaryotes and eukaryotes.

Confocal laser scanning microscopy and the potentiometric fluorescence probe tetramethylrhodamine ethyl ester were used to measure changes in membrane electrical potential (DeltaPsi(m)) in individual mitochondria after isolation or in the living cell. Recordings averaged over small mitochondrial populations revealed a gradual decline in DeltaPsi(m) caused by the light-induced generation of free...

The hypothesis that dihydropyridine (DHP)-sensitive calcium channels have three distinct modes of gating has been examined. The major prediction is that the relative frequencies among modes depend on DHP concentration while the kinetics within a mode do not. We tested this by studying whole-cell and single-channel calcium currents in neonatal rat and adult guinea pig cardiac myocytes in differe...

We present an algorithm for an early detection of the uncapping process of honeybee brood cells. It is a challenging problem, because the appearance of openings varies highly and the combs surface is crowded by bees. The approach consists of two steps, segmentation of the image and analyzing the segments to give a report about openings.

during rutting period, the male one humped camels, extrudes a balloon like organ from one side of the mouth. twelve heads of the slaughtered one humped camels from different sexes were examined. air was blown through natural openings: mouth, nares, esophagus and trachea. cross and longitudinal sections were made in frozen and formalin fixed specimens. it was concluded that soft palate in one hu...

The kinetic behavior of brain Na+ channels was studied in pyramidal cells from rat and cat sensorimotor cortex using either the thin slice preparation or acutely isolated neurons. Single-channel recordings were obtained in the cell-attached and inside-out configuration of the patch-clamp technique. Na+ channels had a conductance of about 16 pS. Patches always contained several Na+ channels, usu...

Many resources are expended to ensure a sterile operating room environment. Efforts are made to prevent exposure of patients to personnel and to achieve positive room pressure to keep out airborne contaminants. Foot traffic into and out of the operating room during surgery can undermine these efforts. The authors investigated the number and duration of operating room door openings during hip an...

Widely used in dentistry, Ti-6Al-4V alloy is difficult to cast and solder, as it frequently exhibits pores inside the structure. This study was conducted to evaluate the effect of joint openings and diameters of laser-welded joints executed in Ti-6Al-4V structures on the presence of pores as checked by radiographic procedures. Sixty dumbbell rods with central diameters of 1.5, 2.0 and 3.5 mm we...

Abstract—Topology optimization technique utilizes constant element densities as design parameters. Finally, optimal distribution contours of the material densities between voids (0) and solids (1) in design domain represent the determination of topology. It means that regions with element density values become occupied by solids in design domain, while there are only void phases in regions wher...

one of the important issues in hydraulic engineering is inspection of local scour depth around bridge pier. using piles is one of the ways for confronting local scour and erosion. in this study, the experiments were conducted in an 8m long, 0.5m deep and 0.25m wide flume. and the effectof using piles and number of them observed on the amount of scour in three different frude numbers. the shape ...