A simulation model for assessing building firesafety

This paper presents a computer simulation technique for analyzing emergency evacuation and building firesafety. The systematic, objective procedure includes mathematical modeling, graph theory and simulation to represent and analyze the building layout.     

The temperature and pressure dependence of the electron and hole mobilities in GaxIn1-xAsyP1-y alloys

A wide range of samples of both n-type and p-type Ga_xIn_1-xAs_yP_1-y on InP has been grown by LPE with carrier concentrations in the low 10¹⁶cm⁻³range. The electron mobility (μ_e) at room temperature decreased from about 4000 cm²V⁻¹s⁻¹ at y = 0 and passed through a shallow minimum near y = 0.25. At high y values, μ_e rose steeply, reaching 11 000 cm²V⁻¹s⁻¹ at the ternary boundary. In the p-type material the hole mobility (μ_p) varied from 140 cm V⁻¹s⁻¹ in InP, passed through a minimum of about 70 cm²V⁻¹s⁻¹ near y = 0.5 and then increased swiftly towards the ternary boundary. The temperature dependence of both μ_e and μ_p suggested the presence of alloy or space-charge scattering. In order to distinguish between these two mechanisms the pressure coefficient of the direct band-gap dE_o/dP was measured as a function of y by observing the movement with pressure of the photoconductive edge. From dE_o/dP the pressure variation of the effective mass was deduced. By measuring the change in electron and hole mobilities with pressure, it was then possible to establish that alloy scattering rather than space-charge scattering was occurring. From the composition dependence of the alloy scattering potentials for electrons and holes predictions have been made of the variation of μ_e and μ_P with temperature, pressure and dopant Presently a Nuffield Science Fellow concentration. At room temperature a maximum electron mobility of about 11,200 cm²V⁻¹ s⁻¹ is indicated. Presently a Nuffield Science Fellow     

Liposome-protoplast interactions

A large number of different biological compounds can be encapsulated in liposomes and then delivered into the cytoplasm of cells by fusing these lipid vesicles with protoplasts. The essential properties of protoplasts and liposomes are briefly described. Examples of two liposome-protoplast interactions, involving the delivery of intermediates of antibiotic biosynthesis into fungi and DNA into Streptomyces are discussed. References are made to other experiments suggesting that liposomes may be useful in many areas of biotechnology.     

Modern developments in mutagenesis

Mutants of Penicillium chrysogenum and Streptomyces clavuligerus have been isolated on the basis of increased sensitivity to far ultraviolet light far (u.v). In the former case the strain was also sensitive to a wide range of other mutagens, including alkylating agents and ionising radiations, but proved not to be hypermutable by any of these, whereas in S. clavuligerus two strains were hypermutable relative to their wild- type progenitor when treated with far u.v. In addition, various environmental conditions, including liquid holding and treatment with caffeine, isoniazid and nalidixic acid, increased mutant yield. The results obtained clearly show that induced mutation frequency can be enhanced both by mutation of genes involved in DNA repair and by modification of environmental conditions during or after mutagenic treatment. The importance of this and other modern developments in mutagenesis for the design of rational industrial strain-improvement programmes is discussed.     

Raman amplification at 1.118 ?m in single-mode fibre and its limitation by Brillouin scattering

A forward Raman gain of 2.9 dB has been measured in a 1.1 km low-loss fibre using an LED at 1.118 ?m as a signal source and a CW Nd: YAG laser as a pump. Backward Brillouin scattering, which depletes the pump power towards the end of the fibre, is found to enhance the Raman gain at the front end.     

Traumatic bowing of the forearm in an adult

A 24-year-old woman sustained a low-velocity, continuous pressure injury to the right forearm from a conveyer belt machine. The accident caused bowing of the radius and ulna, an injury not previously reported in adults. A closed manipulation with the patient under general anesthesia required considerable force to obtain partial reduction of the radial bowing and almost complete correction of the ulnar bowing. Follow-up examination at two years demonstrated no loss of position but persistent radial bowing. The injury is a good illustration of plastic deformation in bone which is a rare condition in adults due to the elastic properties of bone and typical fracture mechanics.     

Personal responsibility and altruism in children.

Applied P. G. Zimbardo's (1970) deindividuation model to the study of prosocial behavior by asking 177 4–13 yr old Halloween trick-or-treaters in groups of 2–5 Ss to donate candy to hospitalized children under 3 conditions. The designation of personal responsibility for the amount donated was manipulated as follows: no child identified as responsible; one child identified as responsible; and each child identified as responsible. As predicted, personal responsibility increased the likelihood of contributing as well as the number of candies donated. Assigning individual responsibility increased the number of candies donated by each S only if they were in small groups. The absence of a similar outcome among Ss in large groups suggests that the greater social support and/or the greater potential for the diffusion of responsibility in these groups effectively countered the effect of the manipulation of responsibility. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Estimation of the monomeric phenolics of ciders

A method is described for the separation and quantitative determination of the monomeric phenolics of ciders. These are fractionally eluted from a silica-gel column with 2-methylpropan-2-ol/chloroform mixtures of increasing 2-methylpropan-2-ol content. The u.v. spectrum of each fraction is obtained in the range 250-400 nm. Fractions containing hydroxycinnamic acid esters of quinic acid are first irradiated with u.v. light to equilibrate cis and trans forms. The concentration of each of the phenolics is calculated from extinctions at appropriate wavelengths. Ciders from some cider-apple cultivars contained in order of decreasing concentration 5-chlorogenic acid, 4-p-coumarylquinic acid, catechins, phloridzin and phloretin xyloglucoside. In one cultivar catechins were undetectable while in others they exceeded the p-coumarylquinic acid. The contribution of the phenolics to the tannin content is discussed.     

Reflectance spectroscopy of oxide films. I. A theoretical study

Theoretical reflectance spectra for a thin film on an infinite substrate (such as an oxide layer on a metal) have been calculated, to assess the combined effects of absorption bands, interference and surface structure on film identification and the accuracy of film thickness measurements.