Comparative clinical and angiographic analysis of the initial efficacy and long-term follow-up of Wiktor stent implantation with conventional balloon angioplasty

This study was retrospectively designed to examine if the Wiktor stent, a balloon-expandable tantalum coil stent, provides a more favorable procedural and long-term clinical and angiographic outcome than does conventional coronary balloon angioplasty (POBA). From April 1995 to April 1996, we implanted 56 Wiktor stents in 46 lesions (LAD: 23, RCA: 16, CX: 7) in 42 patients (average age 53 +/- 10 years). Coronary lesions from the stent group were matched with similar lesions of another 42 POBA patients whose characteristics were identical to the Wiktor group. Revascularization indications in the Wiktor and POBA groups, respectively, were recent myocardial infarction (RMI) (45%, 40%), unstable (31%, 39%) and stable (24%, 21%) angina pectoris. 7% of the stents and 17% of the POBA balloons were less than 3 mm in diameter (p > 0.05). Procedural success was significantly greater in the Wiktor group than in the POBA group (100% vs. 92%, p < 0.05). Neither major cardiac event (death, CABG, acute myocardial infarction) nor (sub)acute occlusion was encountered in the Wiktor group during the hospitalization period and 1 month follow-up. There was 1 urgent CABG and 4 subacute occlusions in the POBA group. Control angiography at 8 months was performed in patients of both groups, of whom some were symptomatic at long-term follow-up or completely event free for 8 months. Angiographic restenosis (> 50% diameter stenosis) occurred in 25% of the Wiktor patients and in 43% of those in the POBA group (p < 0.05). For an 18 month clinical follow-up, 91% of the patients in the Wiktor group were asymptomatic and without ischemia in radionuclide imaging (RI), whereas 79% of the POBA patients were angina-free and 74% were without ischemia in the RI study. In conclusion, Wiktor stent implantation, with no major cardiac event or subacute occlusion, provides a more favorable procedural and long-term clinical and angiographic outcome than does conventional POBA.     

Performance of Masonry Stone Buildings during the March 25 and 28, 2004 A?kale (Erzurum) Earthquakes in Turkey

This paper reviews the performance of stone masonry buildings during the March 25 and 28, 2004, A?kale (Erzurum) earthquakes. A?kale is a township located 35?km from Erzurum city in Turkey. A majority of the buildings in the affected region are built in masonry. Most of the masonry buildings were formed with random or coursed stone walls without any reinforcement supporting heavy clay tile roofing over wooden logs. A large number of such buildings were heavily damaged or collapsed. The cracking and failure patterns of the buildings are examined and interpreted relative to current provisions for earthquake resistance of masonry structures. The damages are due to several reasons such as site effect, location, and length of the fault, and the poor construction quality of the buildings. In addition to these reasons, the two earthquakes hit the buildings within three days, causing progressive damage. Low strength stone masonry buildings with mud mortar are weak against earthquakes, and should be avoided in high seismic zones.     

Utilization of Refractory Metals and Alloys in Fusion Reactor Structures

In design of fusion reactors, structural material selection is very crucial to improve reactor’s performance. Different types of materials have been proposed for use in fusion reactor structures. Among these materials, refractory metals and alloys having capability to withstand high temperatures and high neutron wall loads have been considered to get high power density in fusion reactors. However, these materials have insufficient technological database and are very expensive compared to steels. In addition to that, except chromium and some chromium alloys they show no low activation property. This study gives an overview of potential of refractory metals and alloys for possible use in fusion reactors.     

Colloid retention in porous media: mechanistic confirmation of wedging and retention in zones of flow stagnation

A three-dimensional particle tracking model for colloid transport in porous media was developed that predicts colloid retention in porous media in the presence of an energy barrier via two mechanisms: (1) wedging of colloids within grain to grain contacts; (2) retention of colloids (without attachment) in flow stagnation zones. The model integrates forces experienced by colloids during transport in porous media, i.e., fluid drag, gravity, diffusion, and colloid-surface Derjaguin-Landau-Verwey-Overbeek interactions. The model was implemented for a fluid flow field that explicitly represented grain to grain contacts. The model utilized a variable time stepping routine to allow finer time steps in zones of rapid change in fluid velocity and colloid-surface interaction forces. Wedging was favored by colloid: collector ratios greater than about 0.005, with this threshold ratio increasing with decreasing fluid velocity. Retention in flow stagnation zones was demonstrated for colloid: collector ratios less than about 0.005, with this threshold decreasing with increasing fluid velocity. Both wedging and retention in flow stagnation zones were sensitive to colloid-surface interaction forces (energy barrier height and secondary energy minimum depth). The model provides a mechanistic basis for colloid retention in the presence of an energy barrier via processes that were recently hypothesized to explain experimental observations.     

Effect of partial removal of prolamins on some chemical and functional properties of barley flours

In this study, some chemical and functional properties of hulled (BF-1) and hull-less (BF-2) barley flours and their partial prolamin removed forms (PPRF-1 and PPRF-2, respectively) were determined. Total dietary fiber and resistant starch values increased on dry weight basis, conversely β-glucan levels slightly decreased after partial prolamin removing (PPR). Sodium dodecyl sulphatepolyacrylamide gel electrophoresis (SDS-PAGE) patterns of PPRF-1 and PPRF-2 exhibited that PPR was highly achieved. Rapid visco analyzer (RVA) peak and breakdown viscosity values of PPRF-1 and PPRF-2 were higher than BF-1 and BF-2, conversely their setback, trough, and final viscosity values were lower than that of the BF-1 and BF-2, respectively. PPR also caused an increase in water binding capacity and resulted in a decrease on water solubility values of barley flours. Protein solubility of PPRF-1 and PPRF-2 were lower than BF-1 and BF-2, respectively. Emulsifying properties of PPRF-2 were affected negatively from the PPR.     

RELATIONSHIP BETWEEN ORGANIC MATTER,SULPHUR AND PHOSPHATE CONTENTS IN UPPER CRETACEOUS MARINE CARBONATES (KARABOGAZ FORMATION,SE TURKEY): IMPLICATIONS FOR EARLY OIL GENERATION

In this paper, we discuss the relationship between the organic matter, sulphur and phosphate contents of Upper Cretaceous marine carbonates (Karabogaz Formation) in the Adiyaman Petroleum Province of SE Turkey. The results of organic geochemical analyses of core samples obtained from the Karabogaz Formation suggest that phosphate deposition occurred in settings where the water column was oxic to sub-oxic. However, the preservation of organic matter was favoured in anoxic environments. Moreover, the presence of sulphur (especially sulphur incorporated into kerogen) in organic matter-rich layers led to early oil generation. The results of stepwise py-gc analyses are consistent with a model in which, with increasing maturity, S-S and C-S bonds are the first to be eliminated from the macromolecular kerogen structure. Study of the maturity evolution of S-rich kerogen by laboratory pyrolysis implies that marginally mature and/or mature kerogen in the Karabogaz Formation, which may be classified as classic “Type II” kerogen, was most probably Type II/S at lower maturity stages. This enabled oil generation to occur at relatively shallow burial depths and relatively early stages of maturation. It is reasonable to conclude that Type II/S kerogen, overlooked in previous studies, was abundant in TOC-rich intervals in the Karabogaz Formation. Early generation (and expulsion) from Type II/S kerogen may have sourced the sulphur-rich oils in the Adiyaman area oilfields.     

Impact of impregnation with boron compounds on the surface hardness of varnished wood

This study was performed to determine the impact of impregnation with boron compounds on the surface hardness of varnished wood materials. For this purpose, test specimens prepared from Oriental beech (Fagus orientalis Lipsky) and oak (Quercus petreae Lipsky), which met the requirements of ASTM D 358, were impregnated according to ASTM D 1413 with boric acid and borax by a vacuum technique. After impregnation, the surfaces were coated by cellulosic, synthetic, polyurethane, waterborne, acrylic, and acid hardening varnishes in accordance with ASTM D 3023. The surface hardness of the specimens after the varnishing process was determined in accordance with ASTM D 4366. According to the wood type, impregnation material, and varnish type, the surface hardness was highest for the oak impregnated with borax and acrylic varnish and lowest for the oak impregnated with borax and synthetic varnish. Therefore, impregnation with boron compounds showed an increasing impact on the surface hardness of the varnished wood. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

A Multi-step Virtual Screening Protocol for the Identification of Novel Non-acidic Microsomal Prostaglandin E2 Synthase-1 (mPGES-1) Inhibitors

Microsomal prostaglandin E₂ synthase-1 (mPGES-1) is a potential therapeutic target for the treatment of inflammatory diseases and certain types of cancer. To identify novel scaffolds for mPGES-1 inhibition, we applied a virtual screening (VS) protocol that comprises molecular docking, fingerprints-based clustering with diversity-based selection, protein–ligand interactions fingerprints, and molecular dynamics (MD) simulations with molecular mechanics Poisson–Boltzmann surface area (MM-PBSA) calculations. The hits identified were carefully analyzed to ensure the selection of novel scaffolds that establish stable interactions with key residues in the mPGES-1 binding pocket and inhibit the catalytic activity of the enzyme. As a result, we discovered two promising chemotypes, 4-(2-chlorophenyl)-N-[(2-{[(propan-2-yl)sulfamoyl]methyl}phenyl)methyl]piperazine-1-carboxamide ( 6 ) and N-(4-methoxy-3-{[4-(6-methyl-1,3-benzothiazol-2-yl)phenyl]sulfamoyl}phenyl)acetamide ( 8 ), as non-acidic mPGES-1 inhibitors with IC₅₀ values of 1.2 and 1.3 μm , respectively. Minimal structural optimization of 8 resulted in three more compounds with promising improvements in inhibitory activity (IC₅₀: 0.3–0.6 μm ). The unprecedented chemical structures of 6 and 8 , which are amenable to further derivatization, reveal a new and attractive approach for the development of mPGES-1 inhibitors with potential anti-inflammatory and anticancer properties.