Nonparametric Frontier Estimation by Linear Programming

A new method for estimating the frontier of a set of points (or a support, in other words) is proposed. The estimates are defined as kernel functions covering all the points and whose associated support is of smallest surface. They are written as linear combinations of kernel functions applied to the points of the sample. The weights of the linear combination are then computed by solving a linear programming problem. In the general case, the solution of the optimization problem is sparse, that is, only a few coefficients are non zero. The corresponding points play the role of support vectors in the statistical learning theory. The L ₁-norm for the error of estimation is shown to be almost surely converging to zero, and the rate of convergence is provided.     

Uptake and transport of exogenous proteins by respiratory epithelium

The tracer proteins, horseradish peroxidase and ferritin, placed in the trachea of guinea pigs were taken up by epithelial cells and transported to the extracellular space. The interval between the introduction of the tracer proteins into the lumen of the trachea and the morphologic demonstration of the porteins in the extracellular space or within the basal portion of the cells was between 30 and 60 minutes. The proteins were transported in vesicles and no penetration of the epithelial intercellular tight junctions was found. The intercellular tight junctions were made permeable to horseradish peroxidase by anesthetic ether and this permeable epithelium was compared to the vesicle type transport. Transepithelial transport of proteins is a possible mechanism for the introduction of antigenic material into the subepithelial lymphoid tissue and this transport may also be of importance in the late onset type of asthma.     

Effect of therapeutic touch on the well-being of persons with terminal cancer

In this paper, the effect of azelastine hydrochloride, a potent inhibitor of leukotrienes (LTs) and H1 receptors for histamine, was assessed as regards modulation of in vitro eosinophilic chemotaxis. In this respect, chemotaxis of eosinophils (EOS), isolated from the peripheral blood of untreated allergic subjects in the acute phase, was significantly diminished after in vitro treatment with azelastine in comparison to values before treatment. When EOS were pre-incubated with serial dilutions of the drug, it was observed that azelastine inhibited chemotaxis in a dose-dependent fashion. Since azelastine acts in vitro as a regulator of the calcium pump, EOS were pre-incubated with different concentrations (0.6 and 3.0 mM) of Ca++. In these experimental conditions azelastine was able to reduce EOS chemotactic activity only in the presence of 0.6 mM Ca++, whereas with higher Ca++ concentrations (3.0 mM) the inhibitory effect of the drug was abrogated. On the other hand, particular attention was paid to inhaled budesonide, a non halogenated glucocorticosteroid derivative, structurally related to 16 alpha-hydroxy prednisolone, which represents a helpful for treatment mild to moderate asthma. Data obtained after in vitro treatment with budesonide of a group of allergic patients demonstrated that EOS chemotactic activity was significantly reduced in these subjects. Conclusively our data show that 1) azelastine acts as a dose-dependent antagonist of chemotaxis; 2) it may exert this action by inhibiting Ca++ flow into cells; 3) inhaled budesonide may induce inhibition of bronchial inflammation by downregulating EOS chemotactic capacity.     

Is the standard compliance check protocol a valid measure of the accessibility of tobacco to underage smokers?

OBJECTIVE: To determine if the standard compliance check protocol is a valid measure of the experience of underage smokers when purchasing tobacco in unfamiliar communities. SETTING: 160 tobacco outlets in eight Massachusetts communities where underage tobacco sales laws are vigorously enforced. PROCEDURE: Completed purchase rates were compared between underage smokers who behaved normally and inexperienced non-smoking youths who were not allowed to lie or present proof of age (ID). RESULTS: The "smoker protocol" increased the likelihood of a sale nearly sixfold over that for the non-smokers (odds ratio (OR) 5.7, 95% confidence interval (CI) 1.5 to 22). When the youths presented an ID with an underage birth date, the odds of a completed sale increased dramatically (OR 27, 95% CI 3.4 to 212). Clerks judged to be under 21 years of age were seven times more likely to make an illegal sale (OR 7.6, 95% CI 2.4 to 24.0). CONCLUSIONS: Commonly used compliance check protocols are too artificial to reflect accurately the experience of underage smokers. The validity of compliance checks might be improved by having youths present ID, and by employing either tobacco users, or non-tobacco users who are sufficiently experienced to mimic the self confidence exhibited by tobacco users in this situation. Consideration should be given to prohibiting the sale of tobacco by individuals under 21 years of age.     

Evaluations by staff, residents, and community seniors of patronizing speech in the nursing home: Impact of passive, assertive, or humorous responses.

Two studies tested the impact of alternative communication in accommodation strategies. Nursing home staff and residents (and community-residing seniors in Study 2) rated nurse–resident conversational scenarios in which a resident responded passively, directly assertively, or humorously (indirectly assertively) to a patronizing nurse. The nurse then either maintained a patronizing manner or accommodated with a more respectful speech style. Even though all groups devalued the nurse who maintained a patronizing speech style, nursing home residents predictably showed the most acceptance. The directly assertive response by the resident elicited more devaluation of the nonaccommodating nurse than did either passive or humorous responses, but also the least favorable ratings of the resident. Ratings of the humorous response in Study 2 suggested that humor could be a good compromise response style for allowing the receiver of patronizing speech to express opposition to a request, yet still maintain an appearance of competence and politeness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An enhanced Lemaitre model formulation for materials processing damage computation

The Lemaitre damage model is now widely used to deal with coupled damage analyses for various mechanical applications. In this article, different extensions of the model are presented and discussed to deal with complex multiaxial configurations—such as multi-stages bulk forming processes. A specific treatment is done to account for compressive damage growth, and a stress triaxiality cut-off value is considered to avoid any damage evolution below a critical negative triaxiality. The damage potential is also modified to deal with highly ductile materials, and the plastic strain is split into a negative part and a positive part to differentiate damage growth for compressive states of stress and for tensile states of stress. Finally, an anisotropic damage approach based on the comparison between grain flow orientation and principal loading directions is defined. A combination of these extensions is achieved within a single Lemaitre formulation. Application on different examples show the robustness and accuracy of the model defined in this paper.     

Cell-culture compatible silk fibroin scaffolds concomitantly patterned by freezing conditions and salt concentration

The morphology of freeze-dried silk fibroin 3D-scaffolds was modified by varying both the NaCl concentration and the freezing temperature of the silk fibroin solution prior to lyophilization. Scanning electron micrographs showed that slow freezing at −22 °C generated sponge-like interconnected porous networks, whereas fast freezing at −73 °C formed stacked leaflet structures. The presence of millimolar NaCl (50–250 mM) increased the porosity of the scaffolds and generated small outgrowths at their surface, depending on the freezing regime. Our results suggest that the morphological differences seen between the materials likely depend on ice and NaCl hydrate crystal nucleation and growth mechanisms. Infrared spectroscopy and X-ray diffraction analyses revealed that the salt concentration and freezing conditions induced no structural changes in fibroin. The seeding of P19 embryonic carcinoma cells showed that the presence of salt and freezing conditions influenced the cell distribution into the scaffolds, with salt addition increasing the access of cells to deeper regions.     

The predictive role of body image and anti-fat attitudes on attentional bias toward body area in haptic virtual reality environment

Virtual Reality - Evidence suggests that dissatisfaction with body image in women can be enhanced by exposure to media’s idealized images. The theory of social comparison and the avoidance...