A mathematical model for skin burn injury induced by radiation heating

We modify the Pennes model by taking into account the thermal relaxation time of biological tissue. Specifically, we employ the Maxwell–Cattaneo thermal flux law, in conjunction with the fourth power law, to model the effects of high thermal radiation on such skin. The skin is considered to be a 3D triple-layered structure with embedded dendritic countercurrent multi-level blood vessels, artery and vein, where the dimensions and blood flow of the multi-level blood vessels are determined based on the constructal theory of multi-scale tree-shaped heat exchangers. The method is illustrated by a numerical example.     

Effect of airflow setting on the organic composition of woodheater emissions

Fine particle emissions from woodheaters are large contributors to ambient atmospheric pollution in a number of regional centers in Australia. The health impact of woodsmoke is not limited to the particle loading alone, and a wide range of toxic inorganic and organic compounds are also emitted as gases or adsorbed onto particles. The organic composition of woodsmoke was determined from two heater models operated using different airflow settings. Particle emission factors varied between 3 and 36 g per kg dry wood burned, with higher burn rates (open airflow) producing significantly less particle mass per kg wood burned than the low burn rates (closed airflow). Over 90 organic compounds were quantified from the vapor- and particle-phases, including furans, methoxyphenols, and other substituted aromatics, PAHs, maltols, and the sugar levoglucosan. Emission factors for the majority of the particle-phase compounds increased as the airflow was progressively closed, but decreased for some PAHs and other compounds found predominantly in the vapor-phase. Levoglucosan was the single most abundant compound, contributing 5-16% of the total particle mass. Although there was some variation in levoglucosan emissions between heater models, the fact that levoglucosan emissions vary relatively little between airflow conditions for a given heater provides the potential to use it as a general tracer for woodsmoke. In contrast, the mass fractions of many other particle-phase compounds were considerably higher when operated with a closed airflow.     

Acute nicotine fails to alter event-related potential or behavioral performance indices of auditory distraction in cigarette smokers.

Behavioral studies have shown that nicotine enhances performance in sustained attention tasks, but they have not shown convincing support for the effects of nicotine on tasks requiring selective attention or attentional control under conditions of distraction. We investigated distractibility in 14 smokers (7 females) with event-related brain potentials (ERPs) and behavioral performance measures extracted from an auditory discrimination task requiring a choice reaction time response to short- and long-duration tones, both with and without embedded deviants. Nicotine gum (4 mg), administered in a randomized, double-blind, placebo-controlled crossover design, failed to counter deviant-elicited behavioral distraction (i.e., slower reaction times and increased response errors), and it did not influence the distracter-elicited mismatch negativity, the P300a, or the reorienting negativity ERP components reflecting acoustic change detection, involuntary attentional switching, and attentional reorienting, respectively. Results are discussed in relation to a stimulus-filter model of smoking and in relation to future research directions.     

Validation of a Loop-Mediated Amplification/ISO 6579-Based Method for Analysing Soya Meal for the Presence of <Emphasis Type="Italic">Salmonella enterica</Emphasis>

An alternative method for detection of Salmonella spp. in animal feed, based on the use of loop-mediated amplification (LAMP) in conjunction with a standard culturing procedure, was compared with the standard ISO 6579 as reference method, using soya meal as the test matrix. In the method comparison study, the sensitivities for both the alternative and reference methods were 100 %. The relative level of detection was 1.000. Tested against 100 Salmonella and 30 non-Salmonella strains, the LAMP-based method was 99 % inclusive and 100 % exclusive. The interlaboratory trial involved ten laboratories from eight European countries, testing eight samples at three contamination levels: 0 cfu/100 g, 1–5 cfu/100 g and 14–68 cfu/100 g. The trial specificity, or percentage correct identification of uncontaminated samples, was 96.3 % for both the reference methods and the LAMP/ISO 6579 alternative method, thus demonstrating its suitability for adoption as a procedure for rapid identification of Salmonella uncontaminated soya meal.     

Pancreatitis in children and adolescents

The literature on acardiac monsters has been reviewed. The following conclusions were drawn: 1. The probability of their appearance seems considerably higher among monoamniotic than diamniotic monochorionic twin pairs. 2. They seem more likely to occur within monozygotic (MZ) pairs in higher multiple births than in MZ twins. 3. The data are consistent with the suggestion that there is a slight female excess among them.     

Implementation of 3-valued logic with c.o.s.m.o.s. integrated circuits

Two ternary gates realising basic ternary operators (ternary NOR, NAND and invertors) are designed with c.o.s.m.o.s. integrated circuits. Any one of these gates may be used to implement several 3-valued algebras.     

270°C, 1 GHz oscillator-type active antenna

Reported is the first demonstration of an active antenna operating at 1 GHz and at temperatures above 200degC. A Clapp oscillator integrated with a slot-ring antenna generated and transmitted a 1 GHz signal from 25 to 270degC. The oscillation frequency varied by less than 4 over the temperature range.     

Identification of pets and raccoons as sources of bacterial contamination of urban storm sewers using a sequence-based bacterial source tracking method

In urbanized areas, contaminated storm sewers can feed high bacterial levels into free-flowing streams and rivers. Although illicit connections sometimes cause contamination, urban wildlife and free-roaming domesticated or feral pets may be another source. After eliminating illicit connections as sources of high levels of Escherichia coli in two storm sewers tributary to the Huron River in southeast Michigan, the roles of urban wildlife, pets, humans, and birds were investigated using a sequence-based bacterial source tracking technology. After enumeration, E. coli were isolated from water samples collected during spring to fall, 2005. Sequences in the gene beta-glucuronidase of each isolate were compared to sequences of reference strains from humans, raccoons, pets (cats and dogs), and birds. The highest percentage source for six of ten events was pets (ANOVA, p=0.005). Among isolates attributed to pets, strains from cats occurred more frequently on seven of nine events in which pets had a non-zero probability. High raccoon percentages (up to 60%) occurred in late summer and fall, and varied significantly more than in the spring (F-test), possibly reflecting urban raccoon den-site mobility. The sequence-based bacterial source tracking method suggests that feces from pets and raccoons are important contributors to urban storm sewers.