800 resultados para Wooden, Iva


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Locality studies have also been made.

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Double leaves, oriental style, in case.

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This report summarizes the data, observations, methods, assumptions, and decisions for the design of the Relief Well Rehabilitation Project in the Right Abutment Drainage Tunnel at Chief Joseph Dam. Chief Joseph Dam (CJD) is a dam on the Columbia River and is owned and operated by the U.S. Army Corps of Engineers (USACE). It is the second only to Grand Coulee dam as the largest producer of hydropower in the United States. The right abutment drainage tunnel contains wooden stave relief wells. Water flows from these wells which reduces the hydrostatic pressure in the right abutment of the dam. The 22 wells in the floor of the tunnel are 60 years old and are in need of rehabilitation. The objective of this project is to control the groundwater gradient, prevent the movement of sediment, stop total screen collapse, and prevent initiation of backwards erosion and piping in the abutment. The rehabilitation solution is to install new stainless steel screens into the existing wells, backfill the annular space between the old wooden screen and the new stainless steel screens with a 3/8-inch pea gravel filter pack, and install a new top cap to hold the new screen in place. This report documents the data, observations, and methods used to complete the final design. During tunnel inspections USACE geologists observed dislodged end plugs and evidence of sediment movement out of the formation. The relief wells have historically high flows between 6,000 gallons per minute (gpm) to 9,000 gpm. New screens are designed based on as-built data and historic tunnel flow. The new screens are 8-in diameter, 100 slot (0.10-inch) screens. We found that screen diameter and slot size would provide adequate transmitting capacity for most of the relief wells. The filter pack gradation is based on descriptions from foundation construction reports. I found that 3/8-inch pea gravel is appropriate for the abutment material. During design, I also considered an option to install the screens into the relief wells without filter pack. I eliminated this option because it did not meet our rehabilitation objective to prevent total failure of the wooden screens.

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There exists a major cost issue as regards termite damage to wooden structures. A factor in this cost has been the increasing trend towards slab-on-ground construction. Current literature has been reviewed in relation to concerns about the possible public/environmental health consequences of the repeated use of termiticides in large quantities. The previous, current and projected future use patterns of termiticides are reviewed in the context of techniques appropriate for termite control and treatment priorities. The phasing out of organochlorine termiticides in Australia was undertaken to minimise impact of these substances on the environment and to a lesser extent on public health. These persistent chemicals were replaced by substances with high activity but relatively low persistence in the soil. There has also been an increase in the use of alternative methods (e.g. physical barriers) for the control of termites. The transition away from organochlorine termiticides has led to a realisation that significant information gaps exist with regard to replacement chemicals and other technologies. Although relatively persistent, the organochlorine chemicals have a limited lifespan in soils. Their concentrations are gradually attenuated by processes such as transport away from the point of application and biodegradation. Wooden structures originally treated with these substances will, with the passing of time, be at risk of termite infestation. The only available option is re-treatment with chemicals currently registered for termite control. Thus, there are likely to be substantial future increases associated with the cost of re-treatment and repairs of older slab-on-ground dwellings. More information is required on Australian termite biology, taxonomy and ecology. The risks of termite infestation need to be evaluated, both locally and nationally so that susceptible or high risk areas, structures and building types can be identified and preventive measures taken in terms of design and construction. Building regulations and designs need to be able to reduce or eliminate high-risk housing; and eliminate or reduce conditions that are attractive to termites and/or facilitate termite infestation.

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Unexpected inflation, disinflation or deflation cause arbitrary income transfers between an economy's borrowers and lenders. This redistribution results from distorted real interest rates that are too high when price level changes are over-predicted and too low when they are under-predicted. This article shows that in Australia's case, inflation expectations were mostly biased upwards throughout the 1990s, according to the Melbourne Institute of Applied Economic and Social Research series and to a new derived series based on bond yields, implying that real interest rates were too high over this time. In turn, this caused substantial arbitrary income transfers from debtors to creditors, estimated to have averaged up to 3 per cent of gross domestic product over the period.

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The present study describes the isolation of the first neurotoxin (acantoxin IVa) from Acanthophis sp. Seram death adder venom and an examination of its activity at nicotinic acetylcholine receptor (naChR) subtypes. Acantoxin IVa (MW 6815; 0.1-1.0 muM) caused concentration-dependent inhibition of indirect twitches (0.1 Hz, 0.2 ms, supramaximal V) and inhibited contractile responses to exogenous nicotinic agonists in the chick biventer cervicis nerve-muscle, confirming that this toxin is a postsynaptic neurotoxin. Acantoxin IVa (1-10 nM) caused pseudo-irreversible antagonism at skeletal muscle nAChR with an estimated pA(2) Of 8.36 +/- 0.17. Acantoxin IVa was approximately two-fold less potent than the long-chain (Type 11) neurotoxin, alpha-bungarotoxin. With a pK(i) value of 4.48, acantoxin IVa was approximately 25,000 times less potent than a-bungarotoxin at alpha7-type neuronal nAChR. However, in contrast to alpha-bungarotoxin, acantoxin IVa completely inhibited specific [H-3]-methyllycaconitine (MLA) binding in rat hippocampus homogenate. Acantoxin IVa had no activity at ganglionic nAChR, alpha4beta2 subtype neuronal nAChR or cytisine-resistant [H-3]-epibatidine binding sites. While long-chain neurotoxin resistant [H-3]-MLA binding in hippocampus homogenate requires further investigation, we have shown that a short-chain (Type 1) neurotoxin is capable of fully inhibiting specific [H-3]-MLA binding. (C) 2004 Elsevier Inc. All rights reserved.

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Stable expression of human groups IIA and X secreted phospholipases A(2) (hGIIA and hGX) in CHO-K1 and HEK293 cells leads to serum- and interleukin-1beta-promoted arachidonate release. Using mutant CHO-K1 cell lines, it is shown that this arachidonate release does not require heparan sulfate proteoglycan- or glycosylphosphatidylinositol-anchored proteins. It is shown that the potent secreted phospholipase A(2) inhibitor Me-Indoxam is cell-impermeable. By use of Me-Indoxam and the cell-impermeable, secreted phospholipase A(2) trapping agent heparin, it is shown that hGIIA liberates free arachidonate prior to secretion from the cell. With hGX-transfected CHO-K1 cells, arachidonate release occurs before and after enzyme secretion, whereas all of the arachidonate release from HEK293 cells occurs prior to enzyme secretion. Immunocytochemical studies by confocal laser and electron microscopies show localization of hGIIA to the cell surface and Golgi compartment. Additional results show that the interleukin-1beta-dependent release of arachidonate is promoted by secreted phospholipase A(2) expression and is completely dependent on cytosolic (group IVA) phospholipase A(2). These results along with additional data resolve the paradox that efficient arachidonic acid release occurs with hGIIA-transfected cells, and yet exogenously added hGIIA is poorly able to liberate arachidonic acid from mammalian cells.