The various Sendai virus C proteins are not functionally equivalent and exert both positive and negative effects on viral RNA accumulation during the course of infection

Recombinant Sendai viruses were prepared which cannot express their Cprime, C, or Cprime plus C proteins due to mutation of their respective start codons ([Cprime-minus], [C-minus] and [double mutant], respectively). The [Cprime-minus] and [C-minus] stocks were similar to that of wild-type (wt) virus in virus titer and plaque formation, whereas the double-mutant stock had a much-reduced PFU or 50% egg infective dose/particle ratio and produced very small plaques. Relative to the wt virus infection, the [Cprime-minus] and [C-minus] infections of BHK cells resulted in significantly greater accumulation of viral RNAs, consistent with the known inhibitory effects of the Cprime and C proteins. The double-mutant infection, in contrast, was delayed in its accumulation of viral RNAs; however, once accumulation started, overaccumulation quickly occurred, as in the single-mutant infections. Our results suggest that the Cprime and C proteins both provide a common positive function early in infection, so that only the double mutant undergoes delayed RNA accumulation and exhibits the highly debilitated phenotype. Later in infection, the same proteins appear to act as inhibitors of RNA accumulation. In infections of mice, [Cprime-minus] was found to be as virulent as wt virus whereas [C-minus] was highly attenuated. These results suggest that the Cprime and C proteins cannot be functionally equivalent, since C can replace Cprime for virulence in mice whereas Cprime cannot replace C.     

Platelet activating factor and thromboxane B2 production after cardiopulmonary bypass

Since its original discovery as the neuroendocrine hormone responsible for inhibiting growth hormone (GH) secretion, our understanding of the functions of somatostatin [or somatotrophin release inhibitory hormone (SRIH)], both in the periphery and the CNS, has grown enormously. With the cloning of five SRIH receptors, much interest has centred recently on the potential use of SRIH analogues in the treatment of clinical conditions ranging from human cancers to Alzheimer's and Parkinson's diseases. There is a growing recognition that the physiological functions of GH also need to be extended beyond its role in growth control, e.g. to a role in the maintenance of normal immune, cardiovascular and reproductive functions. Here, Glenda Gillies addresses the importance of somatostatinergic systems in regulating the sexually dimorphic patterns of GH secretion as well as their influence on other endocrine hormones. She also considers the neurotransmitter/neuromodulator actions of SRIH within the hypothalamus, where it is involved in the neural control and integration of many aspects of endocrine function, as well as its potential role in the maturation of the hypothalamus during the critical perinatal period.     

Human phylogenetic relationships according to the D1S80 locus

By analyzing the allelic frequencies at the D1S80 locus in 43 human populations, we show that the locus is polymorphic globally and that it can be used to discriminate between major racial groups and subpopulations through phylogenetic analysis. Although the use of informative multiple loci generally provides more accurate phylogenetic relationships, in instances where time and/or target DNA availability is limited, D1S80 could provide useful data to discriminate between human groups. Also, knowledge of which loci independently provide accurate phylogenetic relationships, such as the D1S80, can be used to design more accurate multi-locus combinations. In addition, allele frequencies at the locus are reported, for the first time, for Bahamian individuals of African origin and for Chimila, Bari, and Navajo (Ca?oncito Valley) native Americans. Allelic data was obtained using standard polymerase chain reaction (PCR) techniques. In the four new populations, 65 genotypes and 20 segregating alleles were observed. All populations conformed to Hardy-Weinberg expectations except the Chimila.     

Dynamic Centrifuge Testing of Slickensided Shear Surfaces

Movement along preexisting slickensided rupture surfaces in overconsolidated clay and clay shale slopes can represent a critical sliding mechanism during earthquakes. The seismic behavior of preexisting slickensided surfaces in overconsolidated clay was examined by performing dynamic centrifuge model tests of two slickensided sliding block models constructed using Rancho Solano lean clay. Dynamic shear displacements were concentrated along the preformed slickensided surfaces. The peak shear resistances mobilized along the slickensided surfaces during dynamic loading were 90–120% higher than the drained residual strength measured prior to shaking. To accurately predict the displacements of the sliding blocks using Newmark’s method, it was necessary to use dynamic strengths that were 37–64% larger than the drained residual strength of the soil. Dynamic loading caused a positive pore pressure response in the soil surrounding the slickensided planes. The postshaking shear strengths were 17–31% higher than those measured prior to shaking.     

A wide-panel forming process to replace conventional roll forming

The geometric basis for the design of a new process to form sheet metal into a flat, corrugated product is described. The underlying principle is to determine a surface between entry of the sheet into the device and the exit of the formed product such that all points across the width of the sheet under go as nearly as possible similar deformation histories and also that longitudinal strain in the sheet is minimized. The surface for forming a product having a sinusoidal profile and also that for a trapezoidal profile are presented as examples. For the sinusoidal product, an empirical equation is developed that relates the strain during forming with the initial and final width, the forming length and the number of profile segments.A physical model shows that a sheet can be formed to such a surface without straining or buckling. Although this paper does not describe the type of tooling or forming machine that would be used to plastically deform steel sheet, the authors believe such a device can be constructed. The results suggest that the new approach would reduce defects such as edge-wave, oil-canning and splitting and that the overall length of the forming device could be an order of magnitude smaller than that for existing roll-forming lines.     

Glycerol transformations on polysaccharide derived mesoporous materials

New polysaccharide based solid acids are excellent catalysts for selective chemical transformations of glycerol. Reasonable selectivities to mono-, di- and triacetylated glycerols can be obtained by controlled microwave activation of glycerol–acetic and solid acid mixtures. Etherifications of glycerol using a range of alcohols have also been achieved and with a degree of selectivity to both 1- and 2-positions. The use of the Starbon^® material as a support for palladium further extends the range of heterogeneous catalysed chemistry to the selective oxidations of glycerol to both glycolic and oxalic acids. In all of the reactions, the catalysts can be easily recovered and reused with only a small loss in activity.     

Sorption Behavior of Selected Aldehyde-scavenging Agents in Poly(ethylene terephthalate) Blends

ABSTRACT: Poly(m-xylylene adipamide) (nylon MXD6), D-sorbitol, and a-cyclodextrin aldehyde-scavenging agents were blended with poly(ethylene terephthalate) and thermally pressed into films. Films were stored in an acidified aqueous model solution (pH 3.6) containing a 25 μM mixture of acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and caproaldehyde for 1, 3, 7, and 14 d. The total amount of aldehydes sorbed by films was 2 to 10 times higher for films containing aldehyde-scavenging agents than nonblended films. Aldehyde-scavenging films demonstrated selective scalping, preferring smaller molecular weight aldehydes to larger aldehydes. Partition coefficients for smaller aldehydes were 3 to 6 times greater for aldehyde-scavenging films than control film.     

Subunit rotation in Escherichia coli FoF1-ATP synthase during oxidative phosphorylation

We report evidence for proton-driven subunit rotation in membrane-bound FoF1-ATP synthase during oxidative phosphorylation. A betaD380C/gammaC87 crosslinked hybrid F1 having epitope-tagged betaD380C subunits (betaflag) exclusively in the two noncrosslinked positions was bound to Fo in F1-depleted membranes. After reduction of the beta-gamma crosslink, a brief exposure to conditions for ATP synthesis followed by reoxidation resulted in a significant amount of betaflag appearing in the beta-gamma crosslinked product. Such a reorientation of gammaC87 relative to the three beta subunits can only occur through subunit rotation. Rotation was inhibited when proton transport through Fo was blocked or when ADP and Pi were omitted. These results establish FoF1 as the second example in nature where proton transport is coupled to subunit rotation.     

Assessment of the Dynamic Phosphate Model PHOSMOD using Data from Field Trials with Starter Fertilizer to Cereals

Field trials are useful for achieving information about how crops respond to different fertilizer applications. However, the yield is normally only measured at the end of the growing season, and little information about growth and nutrient utilization during the season is obtained. With the aid of models it is possible to simulate plant growth and nutrient uptake from day to day. In the present paper, a mechanistic phosphate (P) model, PHOSMOD, was assessed using measured data from field fertilizer trials, in which spring barley (Hordeum  vulgare L.) was grown with various amounts and placements of fertilizer P under contrasting soil and weather conditions. PHOSMOD is developed by Greenwood et al. (2001a), mainly for vegetable crops and runs interactively at www.qpais.co.uk/phosmod/phos.htm. In the test data plant growth and plant P concentration were recorded at three stages of growth. After some adjustments, the model was able to reproduce the observed responses to band placed P and starter fertilizer in plant dry matter, and to predict differences between soil types in the responses to applied fertilizer. The main adjustments to the model were the inclusion of bulk density in the equation for calculating tortuosity, and modifications to the start and end of the growth curve in order to achieve a shorter period of P uptake. Based on the results from this study, PHOSMOD appears to be a promising tool for predicting effects of different P fertilization strategies, and will in our view be a useful aid for improving the fertilizer planning programs used in Norway today.     

Influence of different preparation and dyeing processes on the physical strength of the Ingeo† fibre component in an Ingeo fibre/cotton blend. Part 2; Bleaching followed by dyeing with disperse and reactive dyes‡

A study has been conducted to examine the effect of a vigorous alkaline scour–bleaching preparation, followed by high temperature dyeing, reduction clearing and a reactive dyeing process on the physical strength of the Ingeo fibre component of an Ingeo fibre/cotton blend. The results indicate that the physical strength will be retained at a technically‐ and commercially‐acceptable level provided that prolonged high temperature processing times are not employed.