242 research outputs found
Modular group algebras with almost maximal Lie nilpotency indices. I
Let K be a field of positive characteristic p and KG the group algebra of a
group G. It is known that, if KG is Lie nilpotent, then its upper (or lower)
Lie nilpotency index is at most |G'|+1, where |G'| is the order of the
commutator subgroup. The authors have previously determined the groups G for
which this index is maximal and here they determine the G for which it is
`almost maximal', that is the next highest possible value, namely |G'|-p+2
Physical Study by Surface Characterizations of Sarin Sensor on the Basis of Chemically Functionalized Silicon Nanoribbon Field Effect Transistor
Surface characterizations of an organophosphorus (OP) gas detector based on
chemically functionalized silicon nanoribbon field-effect transistor (SiNR-FET)
were performed by Kelvin Probe Force Microscopy (KPFM) and ToF-SIMS, and
correlated with changes in the current-voltage characteristics of the devices.
KPFM measurements on FETs allow (i) to investigate the contact potential
difference (CPD) distribution of the polarized device as function of the gate
voltage and the exposure to OP traces and, (ii) to analyze the CPD hysteresis
associated to the presence of mobile ions on the surface. The CPD measured by
KPFM on the silicon nanoribbon was corrected due to side capacitance effects in
order to determine the real quantitative surface potential. Comparison with
macroscopic Kelvin probe (KP) experiments on larger surfaces was carried out.
These two approaches were quantitatively consistent. An important increase of
the CPD values (between + 399 mV and + 302 mV) was observed after the OP sensor
grafting, corresponding to a decrease of the work function, and a weaker
variation after exposure to OP (between - 14 mV and - 61 mV) was measured.
Molecular imaging by ToF-SIMS revealed OP presence after SiNR-FET exposure. The
OP molecules were essentially localized on the Si-NR confirming effectiveness
and selectivity of the OP sensor. A prototype was exposed to Sarin vapors and
succeeded in the detection of low vapor concentrations (40 ppm).Comment: Paper and supporting information, J. Phys. Chem. C, 201
ESR2 Drives Mesenchymal-to-Epithelial Transition in Triple-Negative Breast Cancer and Tumorigenesis In Vivo
Estrogen receptors (ERs) have pivotal roles in the development and progression of triple-negative breast cancer (TNBC). Interactions among cancer cells and tumor microenvironment are orchestrated by the extracellular matrix that is rapidly emerging as prominent contributor of fundamental processes of breast cancer progression. Early studies have correlated ERβ expression in tumor sites with a more aggressive clinical outcome, however ERβ exact role in the progression of TNBC remains to be elucidated. Herein, we introduce the functional role of ERβ suppression following isolation of monoclonal cell populations of MDA-MB-231 breast cancer cells transfected with shRNA against human ESR2 that permanently resulted in 90% reduction of ERβ mRNA and protein levels. Further, we demonstrate that clone selection results in strongly reduced levels of the aggressive functional properties of MDA-MB-231 cells, by transforming their morphological characteristics, eliminating the mesenchymal-like traits of triple-negative breast cancer cells. Monoclonal populations of shERβ MDA-MB-231 cells undergo universal matrix reorganization and pass on a mesenchymal-to-epithelial transition state. These striking changes are encompassed by the total prevention of tumorigenesis in vivo following ERβ maximum suppression and isolation of monoclonal cell populations in TNBC cells. We propose that these novel findings highlight the promising role of ERβ targeting in future pharmaceutical approaches for managing the metastatic dynamics of TNBC breast cancer
Neutral current effects in parity violating nuclear force
The measurements of the ΔI= 1 part of the parity violating nuclear force when combined with information on neutral current couplings from neutriro scattering and pion production experiments allow an estimate of the isoscalar admixture in the neutral current if it nas a vector axial-vector structure has been shown
Instancia comparativa de los paisajes culturales de la región noroeste de la provincia de Corrientes como herramienta para la planificación y gestión territorial
The northwest region of the province of Corrientes is made up of cultural landscapes originating in the times of colonial occupation and early republican years, whose evolution was conditioned by the natural geography that made its development difficult. This condition made possible, however, the conservation of colonial landscapes, although in a precarious state due to the lack of coordinated and collaborative public policies in the regional context. This condition made possible, however, the conservation of colonial landscapes, although in a precarious state due to the lack of coordinated and collaborative public policies in the regional context. To facilitate planning at a regional scale, a comparative analysis of cultural landscapes of five urban centers has been implemented, through a matrix that includes both the urban dimension, through the settlement processes that determined layers of the landscape, and the architectural and spatial dimension, through patterns.La región noroeste de la provincia de Corrientes está conformada por paisajes culturales originados en los tiempos de ocupación colonial y primeros años republicanos, cuya evolución fue condicionada por la geografía natural que dificultó su desarrollo. Esta condición posibilitó, sin embargo, la conservación de paisajes coloniales, aunque en estado precario debido a la falta de políticas públicas coordinadas y colaborativas en el contexto regional.
Para facilitar la planificación a escala regional se ha implementado el análisis comparativo de paisajes culturales de cinco núcleos urbanos, a través de una matriz que incluye tanto la dimensión urbana, a través de los procesos de poblamiento que determinaron capas del paisaje, como la dimensión arquitectónica y espacial, a través de patrones
El paisaje cultural de Caá Catí, su puesta en valor para un turismo sustentable
El trabajo está centrado en el estudio del paisaje cultural la localidad de Caá Catí en la Provincia de Corrientes, declarado de Interés Turístico por Ley provincial N°4346 en 1989. Posee un patrimonio histórico y urbano que se halla mayoritariamente en estado crítico y que requiere acciones de preservación partiendo de la divulgación y formación técnica que deberán tener continuidad con obras concretas de restauración y puesta en valor, según los resultados del diagnóstico realizado para el proyecto PI 17C003 SGCyT UNNE. A propósito del conocimiento producido sobre la localidad Caá Catí y la oportunidad generada por la CNMMYBH con el programa de Poblados Auténticos, la delegada de Corrientes propone a Caá Cati, junto con Loreto y San Miguel …”por su arquitectura, su naturaleza, su historia, su cultura y su gente”. (CNMMYBH). Como corolario del análisis de las variables y diagnóstico, se efectúan recomendaciones sobre la estrategia de la gestión cultural participativa. Es necesario que las políticas a diseñar tengan en cuenta la identidad y características de este Paisaje, de los grupos y el modo de manifestaciones, para que el rescate de la memoria incluya todos estos componentes y a la sociedad. La finalidad es recuperar este recurso patrimonial y paisajístico sobre la base de la conservación sustentable orientada al turismo cultural
School self-efficacy is affected by gender and motor skills: findings from an Italian study
Background: Perceived school self-efficacy (SE) is an important variable in students' activities as it affects their motivation and learning. Further, self-efficacy might represent a good predictor of performance, persistence and perseverance. Motor skills and other physical health determinants are extensively debated and linked to cognitive function in children of developmental age. However, inconclusive evidence supports a definitive relationship between perceived school SE and motor skills among schoolchildren. We conducted a cross-sectional study on 6-11-year-old schoolchildren to evaluate the extent by which perceived school SE and physical health determinants were related. Methods: A SE questionnaire and motor performance battery tests were administered to primary school pupils recruited from 154 sampled schools of northwest Italy. Perceived SE at school was assessed via 12 items from the Caprara's questionnaire. Motor performance scores were obtained from motor skill tests: 4 × 10 m shuttle run test, SRT; standing broad jump, SBJ; six-minute walking test, 6MWT. Results: A total of 3,962 children (M = 2,019; F = 1943) were studied and 68% were normal weight. Overall, a 58% of the sample perceived a high SE, while, as to gender differences, a greater percentage of females perceived high levels of school SE with respect to any other level (χ2 = 38.93, p < 0.0001). Results from multinomial logistic regression analysis revealed that: (i) females perceived higher SE compared to males; (ii) children who performed better in SRT and 6MWT showed higher levels of perceived school SE; (iii) no significant effect was registered for the body weight. Alternative strategies are encouraged to enhance SE through physical education: structured interventions might enhance both complex motor skills and high-order cognitive skills, like SE, in young children
Assessing eating disordered behaviour in overweight children and adolescents: bridging the gap between a self-report questionnaire and a gold standard interview
Sebomic identification of sex- and ethnicity-specific variations in residual skin surface components (RSSC) for bio-monitoring or forensic applications
Background: “Residual skin surface components” (RSSC) is the collective term used for the superficial layer of sebum, residue of sweat, small quantities of intercellular lipids and components of natural moisturising factor present on the skin surface. Potential applications of RSSC include use as a sampling matrix for identifying biomarkers of disease, environmental exposure monitoring, and forensics (retrospective identification of exposure to toxic chemicals). However, it is essential to first define the composition of “normal” RSSC. Therefore, the aim of the current study was to characterise RSSC to determine commonalities and differences in RSSC composition in relation to sex and ethnicity. Methods: Samples of RSSC were acquired from volunteers using a previously validated method and analysed by high-pressure liquid chromatography–atmospheric pressure chemical ionisation–mass spectrometry (HPLC-APCI-MS). The resulting data underwent sebomic analysis. Results: The composition and abundance of RSSC components varied according to sex and ethnicity. The normalised abundance of free fatty acids, wax esters, diglycerides and triglycerides was significantly higher in males than females. Ethnicity-specific differences were observed in free fatty acids and a diglyceride. Conclusions: The HPLC-APCI-MS method developed in this study was successfully used to analyse the normal composition of RSSC. Compositional differences in the RSSC can be attributed to sex and ethnicity and may reflect underlying factors such as diet, hormonal levels and enzyme expression.Peer reviewedFinal Published versio
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