How superhydrophobicity breaks down

A droplet deposited or impacting on a superhydrophobic surface rolls off easily, leaving the surface dry and clean. This remarkable property is due to a surface structure that favors the entrainment of air cushions beneath the drop, leading to the so-called Cassie state. The Cassie state competes with the Wenzel (impaled) state, in which the liquid fully wets the substrate. To use superhydrophobicity, impalement of the drop into the surface structure needs to be prevented. To understand the underlying processes, we image the impalement dynamics in three dimensions by confocal microscopy. While the drop evaporates from a pillar array, its rim recedes via stepwise depinning from the edge of the pillars. Before depinning, finger-like necks form due to adhesion of the drop at the pillar’s circumference. Once the pressure becomes too high, or the drop too small, the drop slowly impales the texture. The thickness of the air cushion decreases gradually. As soon as the water–air interface touches the substrate, complete wetting proceeds within milliseconds. This visualization of the impalement dynamics will facilitate the development and characterization of superhydrophobic surfaces.     

Preliminary Psychometric Properties of the Verbal and Nonverbal Interaction Scale: An Observational Measure for Communication in Persons with Dementia

Little attention has been given to sociable/unsociable communication in persons with dementia despite the importance of these behaviors in maintaining engagement in marital relationships. An observational measure of verbal and nonverbal communication in persons with dementia (Verbal and Nonverbal Interaction Scale-CR) who were engaged in conversations with spouses was tested for reliability and validity. Married persons with dementia were video-recorded at home conversing with spouses over 10 weeks (N = 118 recordings). Reliability [inter-coder (.92), test-retest (r =.61-.77), internal consistency (α =.65 -.79)] were adequate. Following an intervention, the Verbal and Nonverbal Interaction Scale-CR predicted improved communication over 10 weeks. The ratio of sociable to unsociable communication improved by 4.46 points per session [β = 4.46, t(10) = 1.96, p =.039]. VNVIS-CR is recommended to describe sociable and unsociable communication in persons with dementia as they engage in conversations with spouses.     

Eye eccentricity modifies the perception of whole-body rotation

In order to explore the effect of gaze orientation on whole-body rotation perception, ten healthy participants were rotated in the dark while fixating on a visual target located either straight ahead or 15° to the right. A vestibular-memory contingent saccade paradigm was used to estimate the rotation perception. The results attest to the participants’ ability to accurately perceive their rotation, based solely on the intrinsic inputs (somesthetic and mainly vestibular), since the correlation between the imposed body rotation and the saccade amplitude was significant and positive. However, the rotation perception was less accurate and of lesser magnitude when the gaze was deviated in the opposite direction to the rotation than when it was either straight ahead or deviated in the direction of the rotation. This can be interpreted as the perceptual equivalent of Alexander’s law.     

Circulating adhesion molecules in allergic and non-allergic asthma

Circulating forms of adhesion molecules (intercellular-adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin ) are related to the turnover of these molecules on the cell surface. In contrast to the other molecules, the levels of E-selectin probably exclusively reflect the activity of endothelial cells. The aim of this study was to compare levels of circulating adhesion molecules in patients with allergic (AA) and non-allergic asthma (NA) and to relate the levels of soluble adhesion molecules to methacholine responsiveness and lung function. The study comprised 19 patients with AA, 15 patients with NA and 17 healthy subjects. Soluble adhesion molecules, spirometry, methacholine responsiveness and peak flow variability was measured. The group of patients with AA had higher levels of sE-selectin than the reference group (P=0.046). Serum levels of sE-selectin correlated significantly with bronchial responsiveness (r=0.76) and peak flow variability (r=0.75) (P<0.01) in the NA but not in the AA group. All adhesion molecules in AA (P<0.05-<0.001), but only sE-selectin in NA (P<0.05), were correlated to airway conductance. sVCAM-1 was reduced by inhaled steroids (P<0.01). Our results indicate that endothelial cells are activated in asthma and that this activity has a bearing on airflow variability and bronchial responsiveness in NA.     

Diffuse nonatherosclerotic coronary aneurysms: an unusual cause of sudden death in a young male and a literature review

Coronary artery aneurysms are uncommon, usually associated with atherosclerosis and rarely involve all 3 main coronary arteries. Sudden death from documented thrombosis within large coronary aneurysms has been rarely reported. The authors report a case of a previously healthy 36-year-old male who presented with myocardial infarction complicated by sudden cardiac death. The patient was successfully resuscitated, and coronary angiography revealed diffuse, severe aneurysmal disease without evidence of atherosclerosis. A thrombus was visualized in a large aneurysm of the proximal left anterior descending artery, and there was total occlusion of a second diagonal branch, presumably due to thrombus embolization. The patient had no history of Kawasaki disease, and evaluation revealed no inflammatory or autoimmune condition. Optimal treatment and prognosis for patients with nonatherosclerotic coronary aneurysms remains unclear. Our patient was treated medically with chronic warfarin and low-dose aspirin therapy and recovered without complication.     

Decreased pituitary-gonadal secretion in men with obstructive sleep apnea

Decreased libido is frequently reported in male patients with obstructive sleep apnea (OSA). The decline in morning serum testosterone levels previously reported in these patients was within the normal adult male range and does not explain the frequent association of OSA and sexual dysfunction. We determined serum LH and testosterone levels every 20 min between 2200-0700 h with simultaneous sleep recordings in 10 men with sleep apnea and in 5 normal men free of any breathing disorder in sleep. The mean levels and area under the curve of LH and testosterone were significantly lower in OSA patients compared with controls [LH, 24.9 +/- 10.2 IU/liter.h vs. 43.4 +/- 9.5 (P < 0.005); testosterone, 67.2 +/- 11.5 nmol/liter.h vs. 113.3 +/- 26.8 (P < 0.003)]. Four of 10 patients had hypogonadal morning (0700 h) serum testosterone levels. Analysis of covariance (ANCOVA) revealed that the 2 groups differed significantly in the amount of LH and testosterone secreted at night independent of age or degree of obesity. After partialing out body mass index, there was a significant negative correlation between the amounts of LH and testosterone secreted at night and the respiratory distress index, but not with degree of hypoxia. Our findings suggest that OSA in men is associated with dysfunction of the pituitary-gonadal axis. The relation between LH-testosterone profiles and the severity of OSA suggests that sleep fragmentation and, to a lesser extent, hypoxia in addition to the degree of obesity and aging may be responsible for the central suppression of testosterone in these patients.