The hydrolysis of proteins

Temperature effects on hydrolysis reaction in protein amino acid

Gas-liquid chromatography of amino acids in biological substances

Developing gas-liquid chromatographic method for quantitative analysis of amino acids in blood plasma and urin

A study of ASRS reports involving general aviation and weather encounters

Consideration is given to the nature and characteristics of problems involving dissemination of weather information, use of this information by pilots, its adequacy for the purpose intended, the ability of the air traffic control system to cope with weather related incidents, and the various aspects of pilot behavior, aircraft equipment, and NAVAIDS affecting flights in which weather figures. It is concluded from the study that skill and training deficiencies of general aviation pilots are not major factors in weather related occurrences, nor is lack of aircraft equipment. Major problem causes are identified with timely and easily interpreted weather information, judgement and attitude factors of pilots, and the functioning of the air traffic control system

The absolute photometry of the zodiacal light

Absolute photometry of zodiacal ligh

The case for negative senescence

Negative senescence is characterized by a decline in mortality with age after reproductive maturity, generally accompanied by an increase in fecundity. Hamilton (1966) ruled out negative senescence: we adumbrate the deficiencies of his model. We review empirical studies of various plants and some kinds of animals that may experience negative senescence and conclude that negative senescence may be widespread, especially in indeterminate-growth species for which size and fertility increase with age. We develop optimization models of life-history strategies that demonstrate that negative senescence is theoretically possible. More generally, our models contribute to understanding of the evolutionary and demographic forces that mold the agetrajectories of mortality, fertility and growth.

Approximate solutions of problems involving normal operators

AbstractThe spectral theory for unbounded normal operators is used to develop a systematic method of approximating functions of operators with other, more easily computable functions, leading to a priori error estimates in the operator norm. In particular, polynomial approximations are obtained for resolvents and semigroups in terms of inverses and resolvents, respectively

Spatial cueing deficits in dyslexia reflect generalised difficulties with attentional selection

AbstractTraditionally, explanations of spatial cueing effects posit the operation of orienting mechanisms that act to reposition the spatial locus of attention. This process is often viewed to be analogous to the movement of an attentional ‘spotlight’ across the visual field to the cued region and is thought to occur either in an exogenous or endogenous manner, depending on the nature of the cue. In line with this view, anomalous findings in dyslexic groups using paradigms involving brief peripheral cues have been interpreted as evidence for a particular deficiency with stimulus-driven, exogenous orienting. Here, we demonstrate that an exogenous orienting deficit is an unfeasible explanation of recent findings in which dyslexic individuals fail to derive benefit from peripheral cues indicating the location of a target in a single fixation visual search task. In a series of experiments examining cueing effects in normal readers, we find no evidence to support the operation of an attentional orienting mechanism that is (i) fast but transient; (ii) automatic and involuntary; and (iii) preferentially driven by abrupt luminance transients. Rather, we find that the magnitude of obtained benefits is primarily determined by the informational value of the cue (irrespective of how information is conveyed) and the accessibility of the target representation once the cue had been delivered. In addition, we show that dyslexic individuals’ difficulties with cued search do not reflect problems with detecting and localising the cue, and generalise to different cue types. These results are consistent with a general weakness of attentional selection in dyslexia