Voice of the users: an extended study of software feedback engagement

Requirements Engineering - Many software users give feedback online about the applications they use. This feedback often contains valuable requirements information that can be used to guide the...     

Glial cell line-derived neurotrophic factor-dependent RET activation can be mediated by two different cell-surface accessory proteins

Glial cell line-derived neurotrophic factor (GDNF)-dependent activation of the tyrosine kinase receptor RET is necessary for kidney and enteric neuron development, and mutations in RET are associated with human diseases. Activation of RET by GDNF has been shown to require an accessory component, GDNFR-alpha (RETL1). We report the isolation and characterization of rat and human cDNAs for a novel cell-surface associated accessory protein, RETL2, that shares 49% identity with RETL1. Both RETL1 and RETL2 can mediate GDNF dependent phosphorylation of RET, but they exhibit different patterns of expression in fetal and adult tissues. The most striking differences in expression observed were in the adult central and peripheral nervous systems. In addition, the mechanisms by which the two accessory proteins facilitate the activation of RET by GDNF are quite distinct. In vitro binding experiments with soluble forms of RET, RETL1 and RETL2 demonstrate that while RETL1 binds GDNF tightly to form a membrane-associated complex which can then interact with RET, RETL2 only forms a high affinity complex with GDNF in the presence of RET. This strong RET dependence of the binding of RETL2 to GDNF was confirmed by FACS analysis on RETL1 and RETL2 expressing cells. Together with the recent discovery of a GDNF related protein, neurturin, these data raise the possibility that RETL1 and RETL2 have distinctive roles during development and in the nervous system of the adult. RETL1 and RETL2 represent new candidate susceptibility genes and/or modifier loci for RET-associated diseases.     

Performance of functional psychotics on a repetitive task.

On a repetitive task for 2 successive periods of 10 minutes, non-paranoid schizophrenics showed little improvement with practice during the first period, a rise in level of performance after rest, and a fall in level during the second period. Endogenous depressives showed improvement during both periods, but little increase of performance after rest. Differences in performance were significant between the 2 groups. For the schizophrenics there were differences in response rate depending on length of hospitalization. These findings support results of other investigators and are consistent with the theory of differential susceptibility to reactive inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Paradoxical effects in the reaction time of schizophrenics.

"A reaction-time experiment was carried out, using lights of different intensities, to test Pavlov's suggestion that paradoxical effects are commonly found in schizophrenics. It was predicted that whereas normal persons tend to respond more quickly to more intense stimuli, schizophrenics respond more slowly to such 'ultramarginal' stimuli than to lights of weaker intensity. In 22 out of 24 chronic, nonparanoid schizophrenics, RTs to the brighter stimuli were longer than those to weaker stimuli in a first testing session but not in a second. Convalescent, shore-stay schizophrenics and normal controls showed no paradoxical effects. A tentative hypothesis to explain why the chronic patients did not show paradoxical effects on retest is proposed." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interstellar dust laser explorer: a new instrument for elemental and isotopic analysis and imaging of interstellar and interplanetary dust

We present the performance characteristics of a time-of-flight secondary ion mass spectrometer designed for 157 nm laser postionization of sputtered neutrals for high sensitivity elemental and isotopic analyses. The instrument was built with the aim of analyzing rare element abundances in micron to submicron samples such as interstellar grains and cometary dust. Relative sensitivity factors have been determined for secondary ion mass spectrometry which show an exponential dependency against the first ionization potential. This allows elemental abundances to be measured with errors below 25% for most major elements. The accuracy for isotope ratios, where isotopes can be resolved from isobaric interferences, is usually limited only by counting statistics. In laser secondary neutral mass spectrometry, the spatial and temporal overlaps between the laser and sputtered neutral atoms are modeled and predictions of total detection efficiency and isotopic and elemental fractionation are compared with experimental data. Relative sensitivity factors for laser-ionized secondary neutrals from a stainless steel standard are found to vary less than 3% above saturation laser pulse energy enabling more accurate quantification.     

The personality of epileptics: A discussion of the evidence.

"Five basic theories about the personality of epileptics are outlined, and the extent to which they have been affirmed or refuted by clinical and psychological investigations is considered. The findings of studies which have used the Rorschach test are shown to be contradictory, and the inadequacies of this test for research purposes are pointed out. It is argued that progress in this field depends on a recognition and study of the complex environmental and pathophysiological factors involved, and on the development of reliable criteria with which to classify epileptics." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bovine reaginic antibody. I. Rat mast cell degranulation by bovine allergic serum

A method of utilizing morphological changes in rat mast cells to determine reaginic antibody activity in bovine serum is described. This technique, which has been shown to be useful for the diagnosis of allergies in man, relies on the ability of antigen to degranulate mast cells sensitized with allergic serum. Experiments with radioactively-labelled allergic bovine globulin indicated the specificity of the binding of such proteins to rat mast cells. Cross-reaction between reaginic bovine antibody and human IgE was shown by a binding assay involving the uptake of 125I-labelled anti-human IgE globulin by mast cells incubated with bovine passive cutaneous anaphylaxis positive globulin.