Topology-based image segmentation using LBP pyramids

In this paper, we present a new image segmentation algorithm which is based on local binary patterns (LBPs) and the combinatorial pyramid and which preserves structural correctness and image topology. For this purpose, we define a codification of LBPs using graph pyramids. Since the LBP code characterizes the topological category (local max, min, slope, saddle) of the gray level landscape around the center region, we use it to obtain a “minimal” image representation in terms of the topological characterization of a given 2D grayscale image. Based on this idea, we further describe our hierarchical texture aware image segmentation algorithm and compare its segmentation output and the “minimal” image representation.     

Accent, perpetual foreigner stereotype, and perceived discrimination as indirect links between English proficiency and depressive symptoms in Chinese American adolescents.

The current study uses García Coll et al.'s (1996) developmental competence model of ethnic minority children and Kim's (1999) racial triangulation theory as frameworks for investigating the mechanisms whereby early adolescent English proficiency relates to perceived discriminatory experiences and adolescent depressive symptoms. Data from 444 adolescents (239 girls and 205 boys, with a mean age of 13.0 years for Wave 1 and 17.0 years for Wave 2) and their parents living in major metropolitan areas of Northern California were collected. The structural equation modeling analyses indicate that self-reported low levels of English proficiency among Chinese American adolescents in middle school are related to these same students later reporting that they speak English with an accent in high school, which in turn relates significantly to their perceiving that they have been stereotyped as perpetual foreigners. For girls, a perpetual foreigner stereotype relates to perceptions of chronic daily discrimination, increasing the risk of depressive symptoms. For boys, the path is different: A perpetual foreigner stereotype is apparently related to discriminatory victimization experiences, which increase the risk of depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Versatile α,ω‐Disubstituted Tetrathienoacene Semiconductors for High Performance Organic Thin‐Film Transistors

Facile one‐pot [1 + 1 + 2] and [2 + 1 + 1] syntheses of thieno[3,2‐b]thieno[2′,3′:4,5]thieno[2,3‐d]thiophene (tetrathienoacene; TTA) semiconductors are described which enable the efficient realization of a new TTA‐based series for organic thin‐film transistors (OTFTs). For the perfluorophenyl end‐functionalized derivative DFP‐TTA , the molecular structure is determined by single‐crystal X‐ray diffraction. This material exhibits n‐channel transport with a mobility as high as 0.30 cm²V^?1s^?1 and a high on‐off ratio of 1.8 × 10⁷. Thus, DFP‐TTA has one of the highest electron mobilities of any fused thiophene semiconductor yet discovered. For the phenyl‐substituted analogue, DP‐TTA , p‐channel transport is observed with a mobility as high as 0.21 cm²V^?1s^?1. For the 2‐benzothiazolyl (BS‐) containing derivative, DBS‐TTA , p‐channel transport is still exhibited with a hole mobility close to 2 × 10^?3 cm²V^?1s^?1. Within this family, carrier mobility magnitudes are strongly dependent on the semiconductor growth conditions and the gate dielectric surface treatment.     

Use of galactomannan edible coating application and storage temperature for prolonging shelf-life of “Regional” cheese

The objectives of this work were to determine the influence of the application of two different coatings (galactomannan and chitosan) and of storage temperature on the gas exchange rate of “Regional” cheese; subsequently, the coating that showed the greatest influence on the cheese gas exchange and simultaneously decreased the O₂ consumption (_RO₂)$(R_{{\text{O}}_2})$ and the CO₂ production (_RCO₂)$(R_{{\text{CO}}_2})$ rates was applied on cheese, being the shelf-life parameters monitorized through the performance of chemical and microbiological analyses. Both coatings caused a reduction of _RO₂$R_{{\text{O}}_2}$ and _RCO₂$R_{{\text{CO}}_2}$ of the cheese (between 0.19- and 1.30-fold for _RO₂$R_{{\text{O}}_2}$ and between 0.19- and 1.50-fold for _RCO₂$R_{{\text{CO}}_2}$, depending on the temperatures). The cheese coated with the galactomannan coating was the one with the lower values of _RO₂$R_{{\text{O}}_2}$ (between 0.195 and 0.635 mL kg⁻¹ h⁻¹) and _RCO₂$R_{{\text{CO}}_2}$ (between 0.125 and 0.900 mL kg⁻¹ h⁻¹). Temperature was also found to have an important effect on _RO₂$R_{{\text{O}}_2}$ and _RCO₂$R_{{\text{CO}}_2}$, its influence being well described by an Arrhenius equation with coefficients of determination, R², of 0.85 and above. The chemical and microbiological analyses showed that the application of the coating in cheese samples can be used to decrease the water loss and the colour changes during the storage time. The presence of the coating decreased the moisture loss of the cheese in 2.5% and 1.9%, and the weight loss in 3.8% and 3.1% at 4 °C and 20 °C, respectively. Also, the hardness of the cheese can be decreased as a result of the interaction of the presence of the coating with changes in the storing temperature. In the studied range (4–20 °C) temperature has a statistically significant effect in moisture loss, colour change, hardness and total mesophilic bacterial growth.     

Chromenopyrazoles: non-psychoactive and selective CB₁ cannabinoid agonists with peripheral antinociceptive properties

The unwanted psychoactive effects of cannabinoid receptor agonists have limited their development as medicines. These CB?-mediated side effects are due to the fact that CB? receptors are largely expressed in the central nervous system (CNS). As it is known that CB? receptors are also located peripherally, there is growing interest in targeting cannabinoid receptors located outside the brain. A library of chromenopyrazoles designed analogously to the classical cannabinoid cannabinol were synthesized, characterized, and tested for cannabinoid activity. Radioligand binding assays were used to determine their affinities at CB? and CB? receptors. Structural features required for CB?/CB? affinity and selectivity were explored by molecular modeling. Some compounds in the chromenopyrazole series were observed to be selective CB? ligands. These modeling studies suggest that full CB? selectivity over CB? can be explained by the presence of a pyrazole ring in the structure. The functional activities of selected chromenopyrazoles were evaluated in isolated tissues. In?vivo behavioral tests were then carried out on the most effective CB? cannabinoid agonist, 13?a. Chromenopyrazole 13?a did not induce modifications in any of the tested parameters on the mouse cannabinoid tetrad, thus discounting CNS-mediated effects. This lack of agonistic activity in the CNS suggests that this compound does not readily cross the blood-brain barrier. Moreover, 13?a can induce antinociception in a rat peripheral model of orofacial pain. Taking into account the negative results obtained with the hot-plate test, the antinociception induced by 13?a in the orofacial test could be mediated through peripheral mechanisms.     

Switched-Current bandpass Sigma–Delta modulators for AM digital radio receivers

This paper discusses the use of switched-current (SI) circuits to design Band-Pass ΣΔ Modulators (BP-ΣΔMs) suitable for AM digital radio receivers. First of all, the paper briefly outlines the concept and principles of BP-ΣΔMs, and introduces two modulator architectures which are obtained by applying a lowpass-to-bandpass transformation (i.e. z⁻¹→−z⁻²) to a first-order and a second-order Low-Pass ΣΔ Modulator (LP-ΣΔM), respectively. The resulting BP-ΣΔMs, respectively of second-order and of fourth-order, are then used as case studies for SI circuit implementation. Systematic analysis of the errors associated to SI circuits is carried out and models are presented to evaluate their incidence on the performance of BP-ΣΔMs; the significance of the different errors is illustrated via the two selected case studies. Fully-differential regulated-folded cascode SI memory cells are chosen to attenuate these errors. Based on the proposed error models, optimization is carried out to fulfill AM radio requirements in practical modulator implementations. Two IC prototypes have been fabricated in a CMOS 0.8 μm technology, and measured, to validate the presented design methodology. One of these prototypes uses the fourth-order architecture to digitize AM signals, and features 10.5-bit resolution with 60 mW power consumption from a 5 V supply voltage. The other uses the second-order architecture and features 8-bit with 42 mW in the commercial AM band, from 540 to 1600 kHz. Experimental results show correct noise-shaping for sampling frequencies up to 16 MHz, which means a significant operation frequency enhancement as compared to previously reported SI ΣΔ Modulators.     

Suitability of pineapple,Aloe vera,molasses, glycerol,and office paper as substrates in the MixAlco process?

The MixAlco? process biologically converts biomass to carboxylate salts that may be chemically converted to a wide variety of chemicals and fuels. This study looked at the viability of the following substrates: office paper, pineapple residue, Aloe vera rinds, wood molasses, sugar molasses, and glycerol. All agricultural substrates were initially tested to determine their carbohydrate and lignin content because lignin reduces substrate digestibility. Only pineapple residue had a high enough lignin content (18.3%) to necessitate pretreatment. Pineapple residue was treated with excess lime (300 g kg^?1 Ca(OH)₂ on dry biomass, t = 1 h) and then neutralized with CO₂, which reduced the lignin content to 4.89%. All substrates were anaerobically fermented in batch culture with marine microorganisms for 24 days. The acid concentrations (g mixed acid L^?1) were Aloe vera (25.5), office paper (24.0), glycerol (22.6), pineapple residue (17.2), wood molasses (19.4) and sugar molasses (18.9). The conversions (g volatile solids digested g^?1 volatile solids fed) were Aloe vera (0.59), office paper (0.50), glycerol (0.62), pineapple residue (0.52), wood molasses (0.42) and sugar molasses (0.82). The selectivities (g acetic acid equivalents g^?1 VS digested) were Aloe vera (0.64), office paper (0.62), glycerol (0.51), pineapple residue (0.39), wood molasses (0.61) and sugar molasses (0.33).     

Rise velocities and gas-liquid mass transfer of bubbles in organic solutions

Bubble size, shape, rise velocity and liquid side mass transfer coefficient have been experimentally determined for bubbles rising in organic systems, consisting of single or mutually soluble components, namely: alkanes (n-dodecane, n-hexadecane), alcohols (ethanol, 1-butanol, 1-octanol) and mixtures thereof. For pure solvents (alkanes and alcohols alike), it was found that the bubbles are non-spherical, and that both the rise velocity and the mass transfer coefficient are close to those expected for bubbles with a mobile surface.For alkane-alcohol solutions, on the other hand, the bubbles become almost spherical, and their rise velocity and mass transfer coefficient decrease, taking values intermediate between those of rigid bubbles and bubbles with a mobile surface. Trace concentrations of either alkane in alcohol or alcohol in alkane are enough for this effect to be observed. The bubbles, however, never become completely rigid in the whole range of concentrations between pure alkane and pure alcohol.Use of Higbie's equation with experimental value of slip velocity to calculate the mass transfer coefficient, k_L, (system n-dodecane/1-octanol) yields somewhat high predictions of k_L, but follows the trend of experimental k_L with concentration for most of the concentration range. However, for very small concentrations of either component, Higbie's equation gives completely wrong results, both in magnitude and in trend. The reason for this behaviour is unknown.