Preparation and use of a mesoporous silicate material for the removal of tetramethyl ammonium hydroxide (TMAH) from aqueous solution

A cubic mesoporous silicate (CMS) was prepared, characterised, and assessed as an adsorbent for tetramethyl ammonium hydroxide (TMAH) from aqueous solution. The adsorption process was studied as a function of temperature and time. Sorption closely followed the Langmuir model. The adsorption of TMAH on CMS was endothermic and kinetic studies suggest that the overall rate of adsorption was pseudo‐second‐order. Pore diffusion effects contribute to limiting the overall rate of adsorption while at lower initial TMAH concentrations, film diffusion becomes more important. Desorption studies were carried out using water and methanol. Methanol was the superior desorbing agent. © 2001 Society of Chemical Industry     

Effect of interpass temperature on residual stresses in multipass welds produced using low transformation temperature filler alloy

Weld filler alloys that exploit transformation plasticity through low austenite to martensite transformation temperatures offer an effective method of reducing residual stresses in strong steel welds. However, in multipass welds, the heat input from later weld passes may be insufficient to retransform prior welding passes, leading to the accumulation of thermally induced strains and elevated residual stresses. In this work, the residual stress distributions produced around arc welds fabricated with a martensitic weld filler alloy that transforms at a low temperature have been studied as a function of the number of passes deposited and the interpass temperature. It is found that when the interpass temperature is above the transformation temperature of the weld metal, the entire multipass weld transforms as a single entity, thus permitting the optimum exploitation of the transformation plasticity. In contrast, the deposition of new metal with a relatively low interpass temperature leads to increased residual stresses in the underlying layers, reducing or eliminating the beneficial stress states previously created.     

Fate of Fusarium mycotoxins in maize flour and grits during extrusion cooking

Extrusion technology is used widely in the manufacture of a range of breakfast cereals and snacks for human consumption and animal feeds. To minimise consumer exposure to mycotoxins, the levels of deoxynivalenol (DON) and zearalenone (ZON) in cereals/cereal products and fumonisins B₁ and B₂ (FB₁ and FB₂) in maize are controlled by European Union legislation. Relatively few studies, however, have examined the loss of Fusarium mycotoxins during processing. The behaviour of FB₁, FB₂ and fumonisin B₃ (FB₃), DON and ZON during extrusion of naturally contaminated maize flour and maize grits is examined using pilot-scale equipment. DON and ZON are relatively stable during extrusion cooking but the fumonisins are lost to varying degrees. There is some loss of ZON when present in low concentrations and extruded at higher moisture contents. The presence of additives, such as reducing sugars and sodium chloride, can also affect mycotoxin levels. Moisture content of the cereal feed during extrusion is important and has a greater effect than temperature, particularly on the loss of fumonisins at the lower moistures. The effects are complex and not easy to explain, although more energy input to the extruder is required for drier materials. However, on the basis of these studies, the relationship between the concentration of Fusarium toxins in the raw and finished product is toxin- and process-dependent.     

Effect of post-quench delay on stress relieving by cold compression for the aluminium alloy 7050

The objective of this investigation was to determine the influence of post-quench delays on residual stresses in the heat treatable aluminium alloy 7050, when stress relieved by cold compression. Immersion quenching after solution heat treatment introduces high magnitude residual stresses. These residual stresses can be relieved by the controlled application of post-quench plastic deformation. The effect of a delay between quenching and the application of cold compression has been investigated. During this delay, the aluminium alloy undergoes natural aging, which changes the workhardening behaviour of the alloy during subsequent cold compression. Neutron and X-ray diffraction were used to characterise the residual stresses. It was found that reducing the post-quench delay resulted in lower magnitude residual stresses after cold compression.     

Health care for the whole person: Research update.

Quality health care must be informed by the best available scientific knowledge. This article offers research evidence supporting "health care for the whole person." We present an integrative biopsychosocial framework that can serve as a useful foundation for translational research endeavors and the development, evaluation, and dissemination of evidence-based health and mental health interventions. Pain and depression are used as exemplars of the biopsychosocial model. Empirical support for mental health interventions in primary care settings is highlighted, with particular emphasis on the treatment of depression across the life span. Research, practice, and policy implications based on the extant evidence base for health care for the whole person are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transient expression of beta-galactosidase in differentiating sporozoites of Eimeria tenella

A cocktail of seven Listeria monocytogenes isolates of food, human and environmental origin was used to assess the antilisterial activity of the bacteriocins nisin and ALTA 2341 in combination with various atmospheres: air, 100% N2, 40% CO2:60% N2, or 100% CO2. Buffered tryptone soya broth (pH 6.0) was used as the growth medium and incubation was at 4 degrees C (21 days) or 12 degrees C (7 days), or when temperature fluctuated between these values for defined periods. It was observed that atmosphere alone influenced the growth rate of L. monocytogenes, with 100% CO2 exerting the greatest inhibition. A 5 log population increase was observed in all atmospheres after 7 days at 12 degrees C. At 4 degrees C a 4-5 log population increase was observed in air, 100% N2 and 40% CO2:60% N2 within 21 days. Growth was prevented by 100% CO2. In the presence of nisin (400 IU/ml), an increase in the lag phase was observed before growth (5 log population increase after 7 days) in all atmospheres at 12 degrees C. This effect was enhanced at 4 degrees C where a maximum 2 log population increase was observed in all atmospheres except 100% CO2, in which growth was prevented. Increasing the concentration of nisin to 1250 IU/ml prevented L. monocytogenes growth in all atmosphere combinations at 4 and 12 degrees C. Two concentrations of ALTA 2341 were also tested. In the presence of 0.1% ALTA 2341 and at 12 degrees C, a 3-5 log population increase was observed in all atmospheres with the exception of 100% CO2, which prevented L. monocytogenes growth. At 4 degrees C, growth was observed in the combination of 0.1% ALTA 2341 and 100% N2 only (3 log population increase). Use of a higher concentration of ALTA 2341 (1.0%) resulted in a population decrease below the detection level within 24 h in all atmosphere/temperature combinations. Re-growth occurred in the presence of 1.0% ALTA 2341 in all atmospheres at 12 degrees C, and in combination with air or 100% N2 at 4 C. When the effectiveness of either nisin or ALTA 2341 and atmosphere was tested against L. monocytogenes as temperature fluctuated for periods between 4 and 12 degrees C, only the combination of 100% CO2 and 1.0% ALTA 2341 prevented growth. Cells surviving exposure to nisin or ALTA 2341 were recovered from 28 of the 32 combinations tested that contained bacteriocin. Nisin survivors remained sensitive to the bacteriocin. ALTA 2341 survivors had become resistant to the bacteriocin.     

DAD1, the defender against apoptotic cell death, is a subunit of the mammalian oligosaccharyltransferase

DAD1, the defender against apoptotic cell death, was initially identified as a negative regulator of programmed cell death in the BHK21-derived tsBN7 cell line. Of interest, the 12.5-kDa DAD1 protein is 40% identical in sequence to Ost2p, the 16-kDa subunit of the yeast oligosaccharyltransferase (OST). Although the latter observation suggests that DAD1 may be a mammalian OST subunit, biochemical evidence to support this hypothesis has not been reported. Previously, we showed that canine OST activity is associated with an oligomeric complex of ribophorin I, ribophorin II, and OST48. Here, we demonstrate that DAD1 is a tightly associated subunit of the OST both in the intact membrane and in the purified enzyme. Sedimentation velocity analyses of detergent-solubilized WI38 cells and canine rough microsomes show that DAD1 cosediments precisely with OST activity and with the ribophorins and OST48. Radioiodination of the purified OST reveals that DAD1 is present in roughly equimolar amounts relative to the other subunits. DAD1 can be crosslinked to OST48 in intact microsomes with dithiobis(succinimidylpropionate). Crosslinked ribophorin II-OST48 heterodimers, DAD1-ribophorin II-OST48 heterotrimers and DAD1-ribophorin I-ribophorin II-OST48 heterotetramers also were detected. The demonstration that DAD1 is a subunit of the OST suggests that induction of a cell death pathway upon loss of DAD1 in the tsBN7 cell line reflects the essential nature of N-linked glycosylation in eukaryotes.     

Ethanol effect on activation and maintenance of cold stress response in immature rats

Rats at thermoneutral ambient temperature (Ta) exhibit change in thermoregulatory response to ethanol (EtOH) from 2 to 15 days of age. In the present study, rats at 2-3, 8-9, and 14-15 days of age were administered either saline or EtOH (4 g/kg b.wt.;IP) using two different routines to determine EtOH effect on specific cold defense mechanisms. Injection of EtOH in the first routine occurred after exposure to cold Ta, to determine effect on maintenance of cold thermogenesis. EtOH-induced metabolic depression increased from 3 to 8 days of age, with little change after this time. Injection of EtOH in the second routine was at thermoneutral Ta, followed at 20 min postinjection by rapid exposure to cold Ta to determine effect on activation of cold thermogenesis. EtOH-treatment delayed onset of cold thermogenesis at 2-3 and 14-15 days of age, and completely eliminated 8-9-day-old response to cold Ta. Rats exposed to cold Ta at 2-3 days of age exhibited a slower rate of EtOH absorption and lower blood EtOH concentration than rats in the older groups, to explain some age differences in EtOH response.