540 research outputs found
Caracterización química de la Fibra de Coco (Cocus nucifera L.) de México utilizando Espectroscopía de Infrarrojo (FTIR)
There is a growing interest in products with less environmental impact, this makes the use of natural fibers a viable alternative. The use of materials of biological origin is increasing in an attempt to reduce the amount of thermoplastic polymers from non-renewable sources. In this framework, the work characterizes the chemical characterization of coconut fiber (Cocus nucifera L.), by means of infrared spectroscopy (FTIR), and the spectra of the fibers of coconut, from two important growing sites, the Acapulco and San Jerónimo de Juárez regions, in the state of Guerrero, Mexico, the results obtained are compared with other spectra of other natural fibers, due to the high content of lignin, properties are attributed viscoelastic, by which it is inferred that when the fibers are subjected to a compression load or an impact force, the amorphous region (lignin) functions as a buffer and is resilient to the applied phenomena, a desirable characteristic in packaging materials, this proves that the coconut fiber with natural binder, could be a proposal to be used as packing material in packaging, the data corroborate a high percentage of cellulose and lignin present in the samples studied.Existe un creciente interés en productos con menor impacto ambiental, esto hace que el uso de fibras naturales sea una alternativa viable. El uso de materiales de origen biológico está aumentando en un intento de reducir la cantidad de polímeros termoplásticos de fuentes no renovables. En este marco se presenta el trabajo caracterización química de la fibra de coco (Cocus nucifera L.), mediante espectroscopía de infrarrojo (FTIR) , y se muestran los espectros de las fibras de coco, de dos lugares de cultivo importantes, la región de Acapulco y San Jerónimo de Juárez, en el estado de Guerrero, México , los resultados obtenidos son comparados con otros espectros de otras fibras naturales, debido al alto contenido de lignina se le atribuyen propiedades viscoelásticas, por lo que se infiere que al ser sometidas las fibras a una carga de compresión o una fuerza de impacto, la región amorfa (lignina) funciona como amortiguador y es resiliente a los fenómenos aplicados, una característica deseable en los materiales de embalaje, esto prueba que la fibra de coco con aglomerante natural, pudiera ser una propuesta para usarse como material de relleno en embalajes, los datos corroboran un alto porcentaje de celulosa y lignina presenteen las muestras estudiadas
Transiting Exoplanets with JWST
The era of exoplanet characterization is upon us. For a subset of exoplanets
-- the transiting planets -- physical properties can be measured, including
mass, radius, and atmosphere characteristics. Indeed, measuring the atmospheres
of a further subset of transiting planets, the hot Jupiters, is now routine
with the Spitzer Space Telescope. The James Webb Space Telescope (JWST) will
continue Spitzer's legacy with its large mirror size and precise thermal
stability. JWST is poised for the significant achievement of identifying
habitable planets around bright M through G stars--rocky planets lacking
extensive gas envelopes, with water vapor and signs of chemical disequilibrium
in their atmospheres. Favorable transiting planet systems, are, however,
anticipated to be rare and their atmosphere observations will require tens to
hundreds of hours of JWST time per planet. We review what is known about the
physical characteristics of transiting planets, summarize lessons learned from
Spitzer high-contrast exoplanet measurements, and give several examples of
potential JWST observations.Comment: 22 pages, 11 figures. In press in "Astrophysics in the Next Decade:
JWST and Concurrent Facilities, Astrophysics & Space Science Library,
Thronson, H. A., Tielens, A., Stiavelli, M., eds., Springer: Dordrecht
(2008)." The original publication will be available at
http://www.springerlink.co
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Callous-unemotional traits, low cortisol reactivity and physical aggression in children: findings from the Wirral Child Health and Development Study
Callous-unemotional (CU) traits are thought to confer risk for aggression via reduced amygdala responsivity to distress cues in others. Low cortisol reactivity is thought to confer risk for aggression via reduced arousal and this effect may be confined to boys. We tested the hypothesis that the association between childhood CU traits and aggression would be greatest in the absence of the inhibitory effects of cortisol reactivity, and that this effect would be sex dependent. Participants were 283 members of a stratified subsample within an epidemiological longitudinal cohort (WCHADS). Cortisol reactivity to a social stressor was assessed at 5 years. CU traits were reported by mothers at 5 years, and physical aggression by mothers and teachers at age 7. Results showed that CU traits were associated with elevated aggression at 7 years controlling for earlier aggression. There was no main effect of cortisol reactivity on regression. The association between CU traits and aggression was moderated by cortisol reactivity (p = .011) with a strong association between CU traits and aggression in the presence of low reactivity, and a small and non-significant association in the presence of high reactivity. This association was further moderated by child sex (p = .041) with the joint effect of high CU traits and low cortisol reactivity seen only in boys (p = .016). We report first evidence that a combined deficit in inhibitory processes associated with CU traits and low cortisol reactivity increases risk for childhood aggression, in a sex-dependent manner
Major Allergen Content in Allergen Immunotherapy Products: The Limited Value of Numbers
The prevalence of allergic disorders has increased drastically over the last 50 years to the extent that they can be considered epidemic. At present, allergen-specific immunotherapy (AIT) is the only therapy that targets the underlying cause of allergic disorders, and evidence of its superiority is based on data accumulated from clinical trials and observational studies demonstrating efficacy and safety. However, several aspects remain unresolved, such as harmonization and standardization of manufacturing and quantification procedures across manufacturers, homogeneous reporting of strength, and the establishment of international reference standards for many allergens. This article discusses issues related to the measurement of major allergen content in AIT extracts, raising the question of whether comparison of products from different manufacturers is an appropriate basis for selecting a specific AIT product. Allergen standardization in immunotherapy products is critical for ensuring quality and, thereby, safety and efficacy. However, lack of harmonization in manufacturing processes, allergen quantification (methodologies and references), national regulatory differences, clinical practice, and labeling shows that the comparison of AIT products based solely on major allergen amounts is not rational and, in fact, impossible. Moreover, when rating the information given for a specific product, it is necessary to take into account further inherent characteristics of products and their application in clinical practice, such as the state of extract modification, addition of adjuvant or adjuvant system, route of administration (sublingual/ subcutaneous), and cumulative dose as per posology (including the volume per administration). Finally, only convincing clinical data can serve as the basis for product-specific evaluation and cross-product comparability of individual products
Análisis de la relevancia y factibilidad de indicadores de calidad en las unidades de nutrición
Introducción: La evaluación de la calidad en las actividades
sanitarias exige la elección de unos indicadores
acordes con los resultados que queremos medir. De todos
los posibles, debemos priorizar aquellos que nos permitan
obtener la información más relevante sin sobrecargar el
trabajo habitual de nuestras Unidades.
Objetivo: Conocer la opinión de los socios de SENPE
respecto a la relevancia y la viabilidad del uso de una
selección de indicadores de calidad para su aplicación en
nutrición clínica.
Métodos: Encuesta remitida mediante correo electrónico
a los socios de SENPE solicitando a los mismos su
opinión sobre 12 indicadores de calidad, valorándose
cada uno en cuanto a su relevancia y factibilidad de la
aplicación en su medio.
Resultados: Contestaron 40 encuestados de 40 centros
diferentes de 12 comunidades autónomas. En general, los
indicadores fueron considerados más relevantes que factibles.
Los indicadores mejor puntuados fueron: “identificación
en las bolsas de nutrición artificial”, “posición
semi-incorporada del paciente con nutrición enteral por
sonda nasogástrica” y “protocolos clínicos básicos”. Considerando
los indicadores por grupos (de estructura, proceso
o resultado) los mejor valorados fueron: “identificación
del paciente en las bolsas de nutrición artificial”
(estructura), “posición semi-incorporada” y “protocolos
clínicos básicos” (proceso), y “cumplimiento del objetivo
calórico” (resultado).
Conclusión: Los resultados de la encuesta permiten
seleccionar indicadores prioritarios para su aplicación en
las Unidades de NutriciónIntroduction: The quality assessment in health activities
requires the choice of indicators in line with the
results we want to measure. Of all possible, we should prioritize
those that allow us to obtain the most relevant
information without overloading the regular work of our
units.
Objective: To determine the opinion of the members of
SENPE regarding the relevance and feasibility of using a
selection of quality indicators designed for use in clinical
nutrition.
Methods: E-mail survey sent to members of SENPE
asking them their views on 12 quality indicators, evaluating
each in terms of their relevance and feasibility of
implementation in their environment.
Results: 40 respondents answered from 40 centers in 12
different regions. In general, the indicators were considered
more relevant than feasible. The indicators best
rated were: “identification in artificial nutrition bags,
“semi-recumbent position in patient with nasogastric
tube feeding” and “basic clinical protocols”. Considering
the type of indicator: “patient identification in the bags of
artificial nutrition (structure),” a semi-incorporated
“and” basic clinical protocols (process), and “fulfillment
of the caloric goal” (result).
Conclusion: The results of the survey can make a selection
of indicators that could be considered for first-line
introduction in a Nutrition Uni
An Overview of the 2014 ALMA Long Baseline Campaign
A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to
make accurate images with resolutions of tens of milliarcseconds, which at
submillimeter (submm) wavelengths requires baselines up to ~15 km. To develop
and test this capability, a Long Baseline Campaign (LBC) was carried out from
September to late November 2014, culminating in end-to-end observations,
calibrations, and imaging of selected Science Verification (SV) targets. This
paper presents an overview of the campaign and its main results, including an
investigation of the short-term coherence properties and systematic phase
errors over the long baselines at the ALMA site, a summary of the SV targets
and observations, and recommendations for science observing strategies at long
baselines. Deep ALMA images of the quasar 3C138 at 97 and 241 GHz are also
compared to VLA 43 GHz results, demonstrating an agreement at a level of a few
percent. As a result of the extensive program of LBC testing, the highly
successful SV imaging at long baselines achieved angular resolutions as fine as
19 mas at ~350 GHz. Observing with ALMA on baselines of up to 15 km is now
possible, and opens up new parameter space for submm astronomy.Comment: 11 pages, 7 figures, 2 tables; accepted for publication in the
Astrophysical Journal Letters; this version with small changes to
affiliation
Observation of the full 12-hour-long transit of the exoplanet HD80606b. Warm-Spitzer photometry and SOPHIE spectroscopy
We present new observations of a transit of the 111-day-period exoplanet
HD80606b. Using the Spitzer Space Telescope and its IRAC camera on the
post-cryogenic mission, we performed a 19-hour-long photometric observation of
HD80606 that covers the full transit of 13-14 January 2010. We complement this
photometric data by new spectroscopic observations that we simultaneously
performed with SOPHIE at Haute-Provence Observatory. This provides radial
velocity measurements of the first half of the transit that was previously
uncovered with spectroscopy. This new data set allows the parameters of this
singular planetary system to be significantly refined. We obtained a
planet-to-star radius ratio R_p/R_* = 0.1001 +/- 0.0006 that is slightly lower
than the one measured from previous ground observations. We detected a feature
in the Spitzer light curve that could be due to a stellar spot. We also found a
transit timing about 20 minutes earlier than the ephemeris prediction; this
could be caused by actual TTVs due to an additional body in the system or by
underestimated systematic uncertainties. The sky-projected angle between the
spin-axis of HD80606 and the normal to the planetary orbital plane is found to
be lambda = 42 +/- 8 degrees thanks to the fit of the Rossiter-McLaughlin
anomaly. This allows scenarios with aligned spin-orbit to be definitively
rejected. Over the twenty planetary systems with measured spin-orbit angles, a
few of them are misaligned; this is probably the signature of two different
evolution scenarios for misaligned and aligned systems, depending if they
experienced or not gravitational interaction with a third body. As in the case
of HD80606b, most of the planetary systems including a massive planet are
tilted; this could be the signature of a separate evolution scenario for
massive planets in comparison with Jupiter-mass planets.Comment: 14 pages, 9 figures, 2 tables, accepted for publication in A&
Measurement of the Forward-Backward Asymmetry in the B -> K(*) mu+ mu- Decay and First Observation of the Bs -> phi mu+ mu- Decay
We reconstruct the rare decays , , and in a data sample
corresponding to collected in collisions at
by the CDF II detector at the Fermilab Tevatron
Collider. Using and decays we report the branching ratios. In addition, we report
the measurement of the differential branching ratio and the muon
forward-backward asymmetry in the and decay modes, and the
longitudinal polarization in the decay mode with respect to the squared
dimuon mass. These are consistent with the theoretical prediction from the
standard model, and most recent determinations from other experiments and of
comparable accuracy. We also report the first observation of the {\mathcal{B}}(B^0_s \to
\phi\mu^+\mu^-) = [1.44 \pm 0.33 \pm 0.46] \times 10^{-6}27 \pm 6B^0_s$ decay observed.Comment: 7 pages, 2 figures, 3 tables. Submitted to Phys. Rev. Let
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