The shape and dynamics of deformations of viscoelastic fluids by water droplets.

Many studies on the deformation of soft films by liquids confirmed the increase in the radius of the deformation and the decrease in the apparent contact angle. However, due to the thinness, the dynamics of the deformation could not be observed until the thermodynamic equilibrium. Thus, the dynamics on thick soft materials was studied until equilibrium to contrast the effect of different interfacial energy between different soft materials and water. Therefore, we prepared two different polymeric fluids with similar rheology by cross-linking monomers, yet with different contact angles with water. Sometime after water droplets were placed on these thick polymers, 3D profiles of the deformation were recorded. Though the effect of the surface tension was not verified, the same trend in the dynamics was observed as with thin films, except for the decrease in the radius after the initial increase. The three-phase boundaries (TPBs) were found not at the apex of the ridges formed during the transition to equilibrium. By calculating the surface tensions and angles of each interface at the equilibrium, we found that the temporary imbalance among surface tensions induced the slip of the TPBs toward the center of water droplets, thus dislocating the TPBs and decreasing the radius.

Incubatory environment of the scalp impacts pre-emergent hair to affect post-emergent hair cuticle integrity.

OBJECTIVES: To determine whether the oxidative stress transmitted to newly grown hair from an unhealthy scalp has physical consequences to the cuticular condition and function. METHODS: A uniquely designed 24-week clinical study included 8 weeks of pretreatment with a cosmetic shampoo and 16 weeks of treatment with either a potentiated zinc pyrithione (ZPT) antidandruff shampoo or a placebo cosmetic shampoo. This clinical design allowed the growth and acquisition of hair samples under conditions of varying but known scalp health as a result of treating a dandruff/seborrheic dermatitis (D/SD) population. Two complementary methods were used to characterize the integrity of the cuticular surface. Hair surface hydrophobicity was assessed by quantifying water wetting force using a Wilhelmy balance method. Surface structure and porosity were assessed using dynamic vapor sorption (DVS) to gravimetrically quantify water sorption. RESULTS: Chemical oxidative stress to pre-emergent hair has been shown to have negative consequences to hair surface structure. Compared to a placebo shampoo control, use of a potentiated ZPT shampoo improved scalp health and significantly improved the following attributes associated with healthy hair: hair surface hydrophobicity (surface energy) and cuticular moisture barrier effectiveness (dynamic vapor sorption). CONCLUSIONS: Pre-emergent hair can be negatively impacted by the oxidative stress that occurs with an unhealthy scalp, possibly due to metabolic activity of resident microbes. Manifestations of the oxidative stress include altered cuticle surface properties that are responsible for its protective function; these effects are similar in type to those observed by bleaching post-emergent hair. These alterations have the potential to make the hair, once emerged from the scalp, more susceptible to the cumulative physical and chemical insults responsible for hair feel and look, fiber integrity, and overall retention.

Visual adaptation enhances action sound discrimination.

Prolonged exposure, or adaptation, to a stimulus in 1 modality can bias, but also enhance, perception of a subsequent stimulus presented within the same modality. However, recent research has also found that adaptation in 1 modality can bias perception in another modality. Here, we show a novel crossmodal adaptation effect, where adaptation to a visual stimulus enhances subsequent auditory perception. We found that when compared to no adaptation, prior adaptation to visual, auditory, or audiovisual hand actions enhanced discrimination between 2 subsequently presented hand action sounds. Discrimination was most enhanced when the visual action "matched" the auditory action. In addition, prior adaptation to a visual, auditory, or audiovisual action caused subsequent ambiguous action sounds to be perceived as less like the adaptor. In contrast, these crossmodal action aftereffects were not generated by adaptation to the names of actions. Enhanced crossmodal discrimination and crossmodal perceptual aftereffects may result from separate mechanisms operating in audiovisual action sensitive neurons within perceptual systems. Adaptation-induced crossmodal enhancements cannot be explained by postperceptual responses or decisions. More generally, these results together indicate that adaptation is a ubiquitous mechanism for optimizing perceptual processing of multisensory stimuli.

Incidence, duration and causes of intensive care unit admission following pulmonary resection for malignancy.

BACKGROUND: We assessed the overall incidence and duration of ICU admission following pulmonary resection and attempted to identify patients requiring prolonged ICU stay. METHODS: Analysis of prospectively collected data on all patients undergoing pulmonary resection for suspected malignant disease that subsequently required ICU admission between March 2002 and October 2003. RESULTS: Of 170 patients 52 (30%) needed intensive care post-operatively: 21 (12%) for less than 24 h and 31 (18%) for more, for which group the average length of stay was 11.3 days. There was no significant difference between the patient groups at ICU admission in terms of median APACHE II scores (12 vs. 14), gas exchange (PaO2/FIO2, 441 vs. 364 mmHg), estimated post-operative absolute FEV1 (1.62 vs. 1.31 l) or predicted percentage FEV1 (61.8% vs. 44.3%). Mean ICU cost was 1,838 sterling pounds vs. 25,974 sterling pounds per admission, respectively. CONCLUSIONS: Following pulmonary resection some 18% of patients need a protracted ICU stay at considerable cost. Neither severity of illness scoring, indices of gas exchange at ICU admission, nor predicted post-operative FEV1 identifies such patients.

Perceived quality of care and outcomes following spinal cord injury: minority status in the context of multiple predictors.

OBJECTIVE: To determine whether patients with spinal cord injury (SCI) who are members of minority groups experience a disadvantage with regard to quality of care, and investigate predictors of perceived quality of care and indicators of outcome. DESIGN: Correlational analysis of longitudinal data. SAMPLE: One hundred and forty-three individuals with SCI in the first year following injury (43.3% tetraplegia, 56.7% paraplegia; 53.6% of total had complete injuries). SETTING: Hospital and postdischarge (usually outpatient) care at 3 SCI model systems. MAIN OUTCOME MEASURES: Perceived quality of acute, rehabilitative, and continuing care rated by patients according to standard format. Objective indicators of amount of care (eg, length of stay [LOS], charges) and outcomes (eg, medical complications, Functional Independence Measure [FIM] scores, a life satisfaction measure [the Diener Scale], and the Craig Handicap and Reporting Technique [CHART; a community participation scale]). RESULTS: Minorities did not report statistically significant differences in perceived quality of care or other indicators (eg, amount of care, medical complications, FIM gain, life satisfaction, and CHART scores) compared with other groups. Severity of injury affected LOS and activity outcomes. Satisfaction with medical care before the injury significantly predicted perceived quality of acute hospital care, inpatient rehabilitation, and continuing care (P < 0.03, 0.02, and 0.02, respectively). CONCLUSION: A number of factors may affect variations in perceived quality of care and outcomes, but ethnicity is not always the most important predictor. Asking patients about their satisfaction with previous care can assist in distinguishing satisfaction with current care from pre-existing biases.

Acute myocardial ischemia associated with latent left ventricular outflow tract obstruction in the absence of left ventricular hypertrophy.

Left ventricular outflow tract obstruction (LVOTO) is a recognized feature in hypertrophic cardiomyopathy, but can occur in other clinical scenarios such as acute myocardial ischemia. In some patients, LVOTO may only be detectable with provocation testing such as exercise stress. Accurate and timely diagnosis, therefore, relies on recognizing an echocardiographic substrate in which LVOTO may occur, such as ventricular hypertrophy. The investigators describe two cases of latent LVOTO, presenting with acute myocardial ischemia in the absence of obstructive coronary artery disease, in which the diagnosis was delayed because of the absence of hypertrophy, or other recognizable substrate, on the resting echocardiographic study, but became evident during exercise echocardiography.