Robust estimates in generalized partially linear single-index models

A natural generalization of the well known generalized linear models is to allow only for some of the predictors to be modeled linearly while others are modeled nonparametrically. However, this model can face the so called ??curse of dimensionality?? problem that can be solved by imposing a nonparametric dependence on some unknown projection of the carriers. More precisely, we assume that the observations (y _i ,x _i ,t _i ), 1??i??n, are such that t _i ??? ^q , x _i ??? ^p and y _i |(x _i ,t _i )??F(?,?? _i ) with $\mu_{i}=H (\eta(\boldsymbol{\alpha}^{\mathrm{T}}\mathbf{t}_{i})+\mathbf {x}_{i}^{\mathrm{T}}\boldsymbol{\beta} )$ , for some known distribution function F and link function?H. The function ??:???? and the parameters ?? and ?? are unknown and to be estimated. This model is known as the generalized partly linear single-index model. In this paper, we introduce a family of robust estimates for the parametric and nonparametric components under a generalized partially linear single-index model. It is shown that the estimates of ?? and ?? are root-n consistent and asymptotically normally distributed. Through a Monte Carlo study, we compare the performance of the proposed estimators with that of the classical ones.     

Compatibility of different polymers for cord blood-derived hematopoietic progenitor cells

The low yield of hematopoietic progenitor cells (HPC) present in cord blood grafts limits their application in clinics. A reliable strategy for ex vivo expansion of functional HPC is a present goal in regenerative medicine. Here we evaluate the capacity of several two-dimensional polymers to support HPC proliferation. Basic compatibility was tested by measuring cell viability, cytotoxicity and apoptosis of CD34⁺ progenitors that were short and long-term exposed to sixteen bio and synthetic polymers. Resomer^? RG503, PCL and Fibrin might be good alternatives to tissue culture plastic for culture of CB-derived CD34⁺ progenitors. Further, these polymers will be produced in three-dimensional structures and tested for their cytocompatibility.     

Optimization of the determination of tocopherols in Agaricus sp. edible mushrooms by a normal phase liquid chromatographic method

Individual tocopherol profile of five Agaricus mushroom species, widely consumed in Portugal, was obtained by a normal-phase high-performance liquid chromatography (NP-HPLC). It was used a simple solid–liquid extraction procedure without saponification step and the chromatographic separation was achieved using a YMC-Pack Polyamine II column using an isocratic elution with hexane/ethyl acetate (70:30, v/v) at a flow rate of 1.0 mL/min. The effluent was monitored by a fluorescence detector. All the compounds were separated in a period of time of 30 min. The method proved to be sensitive, reproducible and accurate, allowing the determination of tocopherols.     

Family memories in the home: contrasting physical and digital mementos

We carried out fieldwork to characterise and compare physical and digital mementos in the home. Physical mementos are highly valued, heterogeneous and support different types of recollection. Contrary to expectations, we found physical mementos are not purely representational, and can involve appropriating common objects and more idiosyncratic forms. In contrast, digital mementos were initially perceived as less valuable, although participants later reconsidered this. Digital mementos were somewhat limited in function and expression, largely involving representational photos and videos, and infrequently accessed. We explain these digital limitations and conclude with design guidelines for digital mementos, including better techniques for accessing and integrating these into everyday life, allowing them to acquire the symbolic associations and lasting value that characterise their physical counterparts.     

Synthesis,electrochemical characterization of tetra- and octa-substituted dodecyl-mercapto tin phthalocyanines in solution and as self-assembled monolayers

Non-peripherally (α) tetra- (9) and octa-(7) substituted dodecyl-mercapto tin(IV) phthalocyanines were synthesized and their electrochemical behavior studied. Cyclic voltammetry and spectroelectrochemistry show ring-based reductions for 7 and 9, the former shows two ring oxidations, while the latter shows only one ring-based oxidation. The adsorption kinetics of (7) and (9) on gold electrode were investigated by electrochemical impedance spectroscopy (EIS). The equilibrium constant (K) for the adsorption and the Gibbs free energy (ΔG_ads) of the SAMs were evaluated based on the Frumkin isotherm.     

Kinetic study of the electrochemical mineralization of phenols in thin-layer condition

Electrochemical oxidation of p-nitrophenol (PNP) and p-methoxyphenol (PMP) at Bi-doped PbO₂ electrodes under thin-layer condition was studied by Fourier transform infrared spectroelectrochemistry (FTIR) as a function of electrode potential and the initial concentration of organic compound. The results show that complete mineralization of the organic species was achieved at potentials more positive than 1.4 V vs. SCE and the mineralization process was not determined by the concentration of phenols. From the electric charge transferred during thin-layer controlled potential electrolysis, we found that PNP and PMP electrooxidation follow Langmuir-Hinshelwood kinetics.     

Nutrition rehabilitation of undernourished children utilizing Spiruline and Misola

Background  

Malnutrition constitutes a public health problem throughout the world and particularly in developing countries.     

Does Octopus vulgaris have preferred arms?

Previous behavioral studies in Octopus vulgaris revealed lateralization of eye use. In this study, the authors expanded the scope to investigate arm preferences. The octopus's generalist hunting lifestyle and the structure of their arms suggest that these animals have no need to designate specific arms for specific tasks. However, octopuses also show behaviors, like exploration, in which only single or small groups of arms are involved. Here the authors show that octopuses had a strong preference for anterior arm use to reach for and explore objects, which points toward a task division between anterior and posterior arms. Four out of 8 subjects also showed a lateral bias. In addition, octopuses had a preference for a specific arm to reach into a T maze to retrieve a food reward. These findings give evidence for limb-specialization in an animal whose 8 arms were believed to be equipotential. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tejate: Theobroma Cacao and T. bicolor in a Traditional Beverage from Oaxaca, Mexico

Although cacao is most familiar in industrialized Western societies in the form of a processed solid confection, for most of its history the seeds of Theobroma cacao have been most commonly used as ingredients in beverages. Today, in some of the more traditional communities of Mesoamerica, cacao continues to be used primarily in traditional local beverages. One such beverage is tejate, from the Central Valleys of Oaxaca, Mexico. Tejate is a culturally and socially significant beverage, and because it is made with maize and frequently consumed in some rural households, its nutritional contribution may be meaningful. However, tejate preparation is labor intensive and this, combined with changes in the Central Valleys, is leading to changes in the persistence and geographic distribution of this important form of cacao consumption.