Behavioral Patterns of children Involved in bullying episodes

Articulo escrito en colaboración con un investigador de la UNAM SNI IIThis study applied a systematic observation strategy to identify coercive behavioral patterns in school environments. The aim was to describe stability and change in the behavioral patterns of children identified as victims of bullying. To this end, the following specific objectives were defined: (1) to identify episodes of bullying based on the frequency of negative behaviors received and power imbalances between bully and victim; (2) to describe stability and behavioral changes in student victims based on their social and academic conduct and the aggression they receive from peers and teachers; and (3) to describe the functional mechanisms responsible for the process of social organization (i.e., the Social Effectiveness, Social Responsiveness, and Social Reciprocity Indexes). The sample consisted of nine children identified as victims, nine classified as bullies, and nine matched controls, all elementary school students from the study developed at the National Autonomous University of Mexico files. A multidimensional/idiographic/follow-up observational design was used. Observational data describes asymmetry between victims and bullies based on microanalyses of the reciprocity of their behavioral exchanges. In addition, the behavioral patterns of victimized children were identified in relation to their academic activity and social relationships with peers. A model of coercive reciprocity accurately describes the asymmetry found among bullies, victims, and controls. A reduction in victimization was found to be related to: (1) responsiveness to the initiation of social interactions by peers and teachers; and (2) the time allocated to academic behavior during the study

Speckle Metrology

peer reviewe

Fringe Pattern Analysis in Wavelet Domain

We present a full-field technique for single fringe pattern analysis based on wavelet transform. Wavelets technique is a powerful method that quantifies at different scales how spatial energy is distributed. In the wavelets domain, fringe pattern analysis requires spatial modulation by a high-frequency carrier. We realize the modulation process numerically by combining the fringe pattern and its quadrature generated analytically by spiral phase transform. The first application concerns the speckle denoising by thresholding the two-dimensional stationary wavelet transform (2D-swt) coefficients of the detail sub-bands. In the second application, the phase derivatives are estimated from the 1D-continuous wavelet transform (1D-cwt) and 2D-cwt analysis of the modulated fringe pattern by extracting the extremum scales from the localized spatial frequencies. In the third application, the phase derivatives distribution is evaluated from the modulated fringe pattern by the maximum ridge of the 2D-cwt coefficients. The final application concerns the evaluation of the optical phase map using two-dimensional discrete wavelet transform (2D-dwt) decomposition of the modulated fringe pattern. The optical phase is computed as the arctangent function of the ratio between the detail components (high-frequency sub-bands) and the approximation components (low-frequency sub-bands). The performance of these methods is tested on numerical simulations and experimental fringes

Impaired endocytosis in proximal tubule from subchronic exposure to cadmium involves angiotensin II type 1 and cubilin receptors

BACKGROUND: Chronic exposure to low cadmium (Cd) levels produces urinary excretion of low molecular weight proteins, which is considered the critical effect of Cd exposure. However, the mechanisms involved in Cd-induced proteinuria are not entirely clear. Therefore, the present study was designed to evaluate the possible role of megalin and cubilin (important endocytic receptors in proximal tubule cells) and angiotensin II type 1 (AT1) receptor on Cd-induced microalbuminuria. METHODS: Four groups of female Wistar rats were studied. Control (CT) group, vehicle-treated rats; LOS group, rats treated with losartan (an AT1 antagonist) from weeks 5 to 8 (10 mg/kg/day by gavage); Cd group, rats subchronically exposed to Cd (3 mg/kg/day by gavage) during 8 weeks, and Cd + LOS group, rats treated with Cd for 8 weeks and LOS from weeks 5–8. Kidney Cd content, glomerular function (evaluated by creatinine clearance and plasma creatinine), kidney injury and tubular function (evaluated by Kim-1 expression, urinary excretion of N-acetyl-β-D-glucosaminidase (NAG) and glucose, and microalbuminuria), oxidative stress (measured by lipid peroxidation and NAD(P)H oxidase activity), mRNA levels of megalin, expressions of megalin and cubilin (by confocal microscopy) and AT1 receptor (by Western blot), were measured in the different experimental groups. Data were analyzed by one-way ANOVA or Kruskal-Wallis test using GraphPad Prism 5 software (Version 5.00). P < 0.05 was considered statistically significant. RESULTS: Administration of Cd (Cd and Cd + LOS groups) increased renal Cd content. LOS-treatment decreased Cd-induced microalbuminuria without changes in: plasma creatinine, creatinine clearance, urinary NAG and glucose, oxidative stress, mRNA levels of megalin and cubilin, neither protein expression of megalin nor AT1 receptor, in the different experimental groups studied. However, Cd exposure did induce the expression of the tubular injury marker Kim-1 and decreased cubilin protein levels in proximal tubule cells whereas LOS-treatment restored cubilin levels and suppressed Kim-1 expression. CONCLUSION: LOS treatment decreased microalbuminuria induced by Cd apparently through a cubilin receptor-dependent mechanism but independent of megalin

Acoustically Levitated Whispering-Gallery Mode Microlasers

Acoustic levitation has become a crucial technique for contactless manipulation in several fields, particularly in biological applications. However, its application in the photonics field remains largely unexplored. In this study, we implement an affordable and innovative phased-array levitator that enables stable trapping in the air of micrometer dye-doped droplets, thereby enabling the creation of microlasers. For the first time, this paper presents a detailed performance of the levitated microlaser cavity, supported by theoretical analysis concerning the hybrid technology based on the combination of whispering-gallery modes and acoustic fields. The pressure field distribution inside the acoustic cavity is numerically solved and qualitatively matched with the schlieren deflectometry technique. The optical lasing features of the levitated microlasers are highly comparable with those devices based On-a-Chip registering maximum Q-factors of ~ 105, and minimum lasing thresholds ~ 150 nJ cm−2. The emission comb is explained as a sum of multiple individual-supported whispering-gallery modes. The use of novel touchless micrometric lasers, produced with an acoustic levitator brings new technological opportunities based on photonic-acoustic technological platforms

RESPUESTA DE LA SANDÍA (Citrullus lanatus (Thunb.) Matsum. & Nakai) A LAS TÉCNICAS DE BIOFUMIGACIÓN Y SOLARIZACIÓN DEL SUELO

El sector agrícola en México aumentó considerablemente su superficie debido al incremento en la demanda de alimentos por los Estados Unidos de Norteamérica; de ahí la importancia de validar diferentes técnicas de manejo de cultivos, buscando incrementar la producción hortícola. La implementación de técnicas como la biofumigación y la solarización del suelo, constituyen una alternativa en la explotación hortícola. El presente trabajo se realizó en el campo experimental del Departamento de Agricultura y Ganadería de la Universidad de Sonora de julio a diciembre de 2006. Se evaluó el efecto de la solarización del suelo y la biofumigación (incorporación de brócoli como materia orgánica) más solarización, en el cultivo de sandía (Citrullus lanatus (Thunb.) Matsum. & Nakai). En cuanto al rendimiento total del cultivo y el peso del fruto, se observó un incremento con el uso de la combinación de ambas técnicas (biofumigación más solarización). En cuanto a la concentración de sólidos solubles y la firmeza del fruto, ambas técnicas no influyeron en la calidad del fruto. En lo referente al muestreo de fitopatógenos del suelo, el uso de la solarización, al igual que su interacción con la biofumigación, redujo considerablemente la presencia de Fusarium. En cuanto a la evaluación de las malezas, la implementación de la solarización del suelo controló eficazmente la presencia de las mismas

A bioinspired hybrid silica–protein material with antimicrobial activity by iron uptake

A silica–protein hybrid material has been prepared by simultaneous covalent deposition of apoferritin and lactoferrin on functionalized silica. This material exhibits strong antibacterial activity against E. coli due to its high iron-uptake capacity.This work was supported by MINECO and FEDER (project CTQ2009-09344), Junta de Andalucía (project P07-FQM-02899) and BIOSEARCH SA (contract PostBIO)