The temperature dependence of anaerobic glycolysis in beef muscle held in a linear temperature gradient

Measurements have been made of the rate of pH fall post-mortem in excised beef sternomandibularis muscles held in a linear temperature gradient. A minimum rate of pH fall was observed between 10 and 12°C and the rate increased as the temperature was further reduced towards 0°C, a phenomenon known to be accompanied by cold-shortening and attributable to increased activity of the contractile actomyosin ATPase which stimulates glycolysis. The increase in rate observed as the temperature was raised above the 10–12°C minimum, had an activation energy of 40kJ/mol, similar to that of the calcium-independent myosin ATPase.     

Self-control over intrusive experiences.

Describes the case of an 18-yr-old female undergraduate whose presenting problem consisted of recurrent, frightening, and uncontrollable visual sensations. Agreeing that the major problem with the sensations was their intrusive nature, the client cooperated in exercises designed to increase her control over the production and dismissal of them. The exercises involved producing, maintaining, and dismissing the sensations at the verbal signals of the therapist. Praise was given contingent on the client's ability to produce and dismiss the sensations faster and to maintain them longer. With 2 sensations of a particularly frightening nature, exercises were carried out after a relaxation induction. At both the 45- and 85-day follow-up, the client reported substantially reduced incidence of the sensations and no anxiety attributable to them. Data indicate that improvement was attributable to practice and to other manipulations involved in the exercise sessions themselves. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling of noncatalytic fluid-solid reactions: The quasi-steady state assumption

An isothermal, topochemical model for noncatalytic fluid-solid reactions, in spherical pellets, is formulated, solved numerically, and investigated experimentally. The equations are transformed into dimensionless form in order to introduce characteristic dimensionless groups. The dimensionless groups represent the relative effects of the diffusional, fluid film transport, and chemical reaction rates on the system, as well as the ratio of the molar density of the reactant fluid to that of the reactant solid. The model is solved with and without the quasi-steady state assumption in order to investigate the effects of the values of the dimensionless groups on the error introduced by this assumption. The model, without the quasi-steady state assumption, is shown to be an accurate representation of a resin exchange system, and reduces to the quasi-steady state model for appropriate values of the dimensionless groups.     

Electromagnetic syringe

A device is described which can be used as a "hyperdermic syringe" to inject electromagnetic energy into deep-lying tissues.     

Evaporative analyser as a mass detector in the size-exclusion chromatography of coal extracts

The applicability of the evaporative analyser in the size-exclusion chromatography (SEC) of coal derivatives has been explored. The detector, in which the intensity is measured for the light scattered from the finely divided solute particles resulting from evaporation of droplets of chromatographic eluate, is mass responsive, sensitive, and linear for both narrow and gross coal-extract fractions. For molecular masses above 300 the mass response is almost uniform, and there are considerable advantages over the detectors commonly used in SEC. Application to lower molecular mass coal materials is limited by the evaporation of solute along with solvent in the detector.     

Aircraft keyboard ergonomics: a review

The increasing use of complex digital avionics systems has resulted in the aircraft pilot making ever greater use of keyboards. The designer has comparatively little coherent information or guidance to help him select the optimal physical and functional characteristics of the keyboard, but current technology gives him a very wide choice. Much of the current literature relates to studies based on static ground environments and, although there is some evidence derived from studies of aircraft, the majority of the ergonomics data relevant to keyboard design is not easily generalized to the airborne environment. A review of the current military standards underlines this as they are brief and they are not always rigidly adhered to in practice. The factors which are likely to affect keying performance are discussed and the state of ergonomics knowledge in the area reviewed.     

Discrete-time adaptive control for deterministic time-varying systems

There is currently considerable interest in the application of recently developed self-tuning control algorithms to real control problems. However, there exist few algorithms which will work for other than slow time-varying systems. A new algorithm which is able to successfully control unknown systems with quite rapidly varying parameters is presented. Several simulation results are also presented. A convergence proof in the linearly time-varying parameter case is given.     

Television and the Children of Ethnic Minorities

"The issues that are raised by ethnic status are not exclusive to ethnicity but represent circumstances much wider in occurrence that appear more often among ethnic minorities."     

CERAMIC CARBIDE POWDER SYNTHESIS IN A NON-TRANSFERRED ARC PLASMA FLOW REACTOR

A method for the synthesis of fine, pure ceramic carbide powders such as silicon carbide, boron carbide and titanium carbide has been developed involving the thermal dissociation of silica, boron oxide or titanium oxide and methane in a thermal plasma, followed by the formation of the carbides in flight and rapid quenching. A non-transferred arc thermal plasma reactor has been designed, engineered, constructed and operated for this synthesis. The powders have been characterized chemically and physically. Thermodynamic calculations were performed to identify the appropriate experimental conditions and confirm the interpretations of the observed experimental results. A reaction mechanism is proposed based upon the experimental observations and results