The prevalence of preferential nasal breathing in adults

The prevalence of preferential nasal breathing was studied in an awake adult population. One hundred and ninety-four people consented to gentle manual compression of the nostrils. They were advised to 'breathe in and out', but no further information regarding breathing was given to avoid influencing the patient. One hundred and eighty patients (92.8%) commenced immediate regular relaxed breathing. Fourteen patients (7.2%) had difficulty with oral breathing which ranged from irregular mouth breathing associated with distress to no spontaneous respiration. The prevalence of preferential nasal breathing was strongly associated with increasing age (chi 2 for trend, P = 0.007). In addition, a weakly significant association was demonstrated between a history of asthma and this phenomenon (P = 0.047). These findings suggest a tendency for the elderly person to revert to the infant pattern of obligate nasal breathing. Physicians should be aware of this possibility in the elderly patient, especially prior to any procedure which may induce nasal obstruction.     

Comparison of chronic neutral endopeptidase inhibition and furosemide in an ovine model of heart failure

OBJECTIVE: Due to the elevated levels of hematopoietically active cytokines such as tumor necrosis factor (TNF) and granulocyte macrophage colony stimulating factor (GMCSF) in rheumatoid arthritis (RA) serum and synovium, the increased bone marrow activity in RA, and the effectiveness of GMCSF in mobilizing progenitor cell release from the bone marrow into the periphery, we hypothesized that hematopoietic progenitors are altered in the peripheral blood (PB) of patients with RA. METHODS: Flow cytometry assisted cell surface analysis was employed to compare the distribution of myeloid (CD34+CD33+), B lymphoid (CD34+CD10+), and erythroid (CD34+CD71+) committed progenitor cell subsets in the PB of healthy controls and patients with RA. Since RA and Sjogren's syndrome (SS) are related autoimmune disorders, primary SS PB was also investigated. RESULTS: Only those patients with RA exhibiting clinically active disease (RA-A) demonstrated increases in myeloid and B lymphoid progenitor cell subsets. Growth of RA-A progenitors in cytokines promoting myelopoiesis (GMCSF, TNF, stem cell factor) produced increased monocyte and dendritic cell progeny, in support of the flow cytometry data. Lineage committed (CD34+CD38+) progenitors were increased in SS PB (p <0.03). However, these did not correlate with either the myeloid, erythroid, or B lymphoid lineages. CONCLUSION: Distinct alterations in the distribution of PB progenitors are present in RA and primary SS. Since progenitor cells retain a proliferative capacity, their infiltration into the synovial/glandular environment may contribute to the accumulation of inflammatory cells within these sites. We propose that PB progenitors enter the diseased microenvironment through similar mechanisms as mature hematopoietic elements.     

Differentiation of the concepts of luck and skill.

20 Ss from each grade level (kindergarten, Grades 2, 4, 6, and 8) were presented a luck (figures to be matched with a standard were not visible but were on the underside of cards) and a skill (figures were visible) version of a task using items from the Matching Familiar Figures Test. Questioning Ss about the performance of hypothetical others on these tasks revealed 4 levels of differentiation of luck and skill. The least mature Ss focused on the visual complexity of tasks rather than on the fact that the luck task permitted only guessing. On this basis, they expected luck outcomes to reflect effort and considered the luck task to require less effort than the skill task. Only the most mature Ss clearly understood that effort could not affect outcomes on the luck task and selectively attributed skill outcomes to effort and luck outcomes to luck. The most mature Ss also spent less time than did less mature Ss in the face of failure on luck tasks, but spent more time on skill tasks. Findings of age-related differences in the differentiation of skill (effort and ability) and luck and of associated differences in behavior make the analysis of the development of achievement-related cognition and behavior more complete. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Slip homogenization in Al-Li alloys by thermomechanical treatment and its effect on mechanical behaviour

The affects of a pre-ageing stretch and of duplex ageing on slip distribution have been examined in the Al-Li-Cu-Mg-Zr alloy 8090 peak aged at 170 °C. Stretching prior to ageing and duplex ageing were found to effectively homogenize the distribution of S in these alloys. In contrast, in unstretched materials that were not duplex aged, precipitation of S was intense on the grain and subgrain boundaries but scarce elsewhere.Tensile, cyclic stress-strain, long fatigue crack growth and small fatigue crack growth data were gathered. These data showed that slip was planar in the unstretched and duplex-aged materials as compared to materials that were stretched prior to ageing. A model is developed to calculate the diameter where Orowan looping of the S precipitates was likely to give way to shearing of those precipitates. Based on this model, it was concluded that, although the distribution of S precipitates was homogeneous in the duplex-aged materials, the precipitates were too fine to effectively homogenize slip. It was also shown that if the artificial ageing temperature was increased to 190 °C the S precipitates were thicker, leading to a change in deformation behaviour.