The effect of various antimetabolites on nuclear pore formation was studied in synchronized HeLa S(3) cells. The nuclear size was determined by light microscopy and the pore number per unit area of nuclear surface by the freeze-etching technique and electron microscopy. It was found that the inhibition of DNA replication or ribosomal RNA synthesis has no effect on nuclear size increase or pore ...

Filtration performance of woven geotextiles is strongly related to their pore structure parameters, i.e., percent open area (POA) and pore-opening size distribution (PSD). Current methods of determination of pore structure parameters contain inherent disadvantages, whereas image analysis, taking advantage of the two-dimensional structure of woven geotextiles, can be used effectively for this pu...

We describe the simple preparation of nitrocellulose gels and high surface area (300 + m(2) g(-1)) aerogels and their hierarchical pore structures. The solvent in which the gels form greatly influences the pore geometry and size distribution of the gels in both the macro- and mesopore domains.

AIMS To determine alterations which occur in the size and shape of lamina cribrosa (LC) pores in glaucomatous eyes over a period of time. METHODS Baseline and follow up optic disc photographs were retrospectively studied in 39 eyes of 39 patients with glaucoma. Only eyes with a vertical cup to disc ratio equal to or greater than 0.6 were included in the study. In addition, all selected eyes h...

The objective of this study is to obtain quantitative evidence of pore-scale immiscible fluid distribution in oil-wet and water-wet porous media using X-ray computed microtomography. Temporal and spatial saturation profiles, as well as surface and interfacial areas, are thoroughly analyzed through cycles of drainage and imbibition using samples with different wetting characteristics but similar...

BACKGROUND AND AIMS Leaf gas exchange is influenced by stomatal size, density, distribution between the leaf adaxial and abaxial sides, as well as by pore dimensions. This study aims to quantify which of these traits mainly underlie genetic differences in operating stomatal conductance (gs) and addresses possible links between anatomical traits and regulation of pore width. METHODS Stomatal r...

Carbon molecular sieves were prepared from petroleum coke by chemical activation. The effects of activation temperature, holding time, preliminary treatments and activated agent ratio on surface area, pore structure of the carbon molecular sieves produced in our lab were investigated. The specific surface area and average pore size of the carbon are obviously increased with increasing use of ac...

Mesoporous hydroxyapatites were syntesized by self-assembly method using Cetyltrimethylammonium bromide (CTAB) as cationic surfactant and 1-dodecanethiol as pore expander with pore expander/surfactant mass ratio of 4.22 and synthesis temperature of 80 °C in different micellization pH. The field emission-scanning electron microscopy (FESEM), x-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) ...

Periodic pressure measurements made during the depletion of oil fields and virgin pressure measurements through normallyand over-pressured sequences in sedimentary basins both demonstrate that changes in pore pressure and minimum horizontal stress (σh) are coupled to one another. Pore pressure/stress coupling is predicted by poroelastic theory. Data from the North Sea (Ekofisk Field) and Texas ...