1,243 research outputs found
¿Pueden los ácidos grasos omega 3 y 6 contrarrestar los efectos negativos de la obesidad en la gestación?
Precursors to Natural Grammar Learning: Preliminary Evidence from 4-Month-Old Infants
When learning a new language, grammar—although difficult—is very important, as grammatical rules determine the relations between the words in a sentence. There is evidence that very young infants can detect rules determining the relation between neighbouring syllables in short syllable sequences. A critical feature of all natural languages, however, is that many grammatical rules concern the dependency relation between non-neighbouring words or elements in a sentence i.e. between an auxiliary and verb inflection as in is singing. Thus, the issue of when and how children begin to recognize such non-adjacent dependencies is fundamental to our understanding of language acquisition. Here, we use brain potential measures to demonstrate that the ability to recognize dependencies between non-adjacent elements in a novel natural language is observable by the age of 4 months. Brain responses indicate that 4-month-old German infants discriminate between grammatical and ungrammatical dependencies in auditorily presented Italian sentences after only brief exposure to correct sentences of the same type. As the grammatical dependencies are realized by phonologically distinct syllables the present data most likely reflect phonologically based implicit learning mechanisms which can serve as a precursor to later grammar learning
La investigación universitaria sobre educación : dilemas y prácticas
Se presentan los resultados de investigaciones realizadas en un contexto institucional: la Facultad de Educación Elemental y Especial (FEEYE), de la Universidad Nacional de Cuyo durante el bienio 2011-2013 y son resultado de los proyectos subsidiados por la Secretaría de Ciencia, Técnica y Posgrado de la misma Universidad a partir del programa de incentivo a docentes investigadores o
subsidiados por la unidad académica
The adipocyte: a model for integration of endocrine and metabolic signaling in energy metabolism regulation
The ability to ensure continuous availability of energy despite highly variable
supplies in the environment is a major determinant of the survival of all
species. In higher organisms, including mammals, the capacity to efficiently
store excess energy as triglycerides in adipocytes, from which stored energy
could be rapidly released for use at other sites, was developed. To orchestrate
the processes of energy storage and release, highly integrated systems operating
on several physiological levels have evolved. The adipocyte is no longer
considered a passive bystander, because fat cells actively secrete many members
of the cytokine family, such as leptin, tumor necrosis factor-alpha, and
interleukin-6, among other cytokine signals, which influence peripheral fuel
storage, mobilization, and combustion, as well as energy homeostasis. The
existence of a network of adipose tissue signaling pathways, arranged in a
hierarchical fashion, constitutes a metabolic repertoire that enables the
organism to adapt to a wide range of different metabolic challenges, such as
starvation, stress, infection, and short periods of gross energy excess
Mitochondrial cristae-remodeling protein OPA1 in POMC neurons couples Ca2+ homeostasis with adipose tissue lipolysis
Appropriate cristae remodeling is a determinant of mitochondrial function and bioenergetics and thus represents a crucial process for cellular metabolic adaptations. Here, we show that mitochondrial cristae architecture and expression of the master cristae-remodeling protein OPA1 in proopiomelanocortin (POMC) neurons, which are key metabolic sensors implicated in energy balance control, is affected by fluctuations in nutrient availability. Genetic inactivation of OPA1 in POMC neurons causes dramatic alterations in cristae topology, mitochondrial Ca2+ handling, reduction in alpha-melanocyte stimulating hormone (α-MSH) in target areas, hyperphagia, and attenuated white adipose tissue (WAT) lipolysis resulting in obesity. Pharmacological blockade of mitochondrial Ca2+ influx restores α-MSH and the lipolytic program, while improving the metabolic defects of mutant mice. Chemogenetic manipulation of POMC neurons confirms a role in lipolysis control. Our results unveil a novel axis that connects OPA1 in POMC neurons with mitochondrial cristae, Ca2+ homeostasis, and WAT lipolysis in the regulation of energy balance
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy
We measure the energy emitted by extensive air showers in the form of radio
emission in the frequency range from 30 to 80 MHz. Exploiting the accurate
energy scale of the Pierre Auger Observatory, we obtain a radiation energy of
15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV
arriving perpendicularly to a geomagnetic field of 0.24 G, scaling
quadratically with the cosmic-ray energy. A comparison with predictions from
state-of-the-art first-principle calculations shows agreement with our
measurement. The radiation energy provides direct access to the calorimetric
energy in the electromagnetic cascade of extensive air showers. Comparison with
our result thus allows the direct calibration of any cosmic-ray radio detector
against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI.
Supplemental material in the ancillary file
Central blood pressure and pulse wave velocity: relationship to target organ damage and cardiovascular morbidity-mortality in diabetic patients or metabolic syndrome. An observational prospective study. LOD-DIABETES study protocol
<p>Abstract</p> <p>Background</p> <p>Diabetic patients show an increased prevalence of non-dipping arterial pressure pattern, target organ damage and elevated arterial stiffness. These alterations are associated with increased cardiovascular risk.</p> <p>The objectives of this study are the following: to evaluate the prognostic value of central arterial pressure and pulse wave velocity in relation to the incidence and outcome of target organ damage and the appearance of cardiovascular episodes (cardiovascular mortality, myocardial infarction, chest pain and stroke) in patients with type 2 diabetes mellitus or metabolic syndrome.</p> <p>Methods/Design</p> <p><b>Design</b>: This is an observational prospective study with 5 years duration, of which the first year corresponds to patient inclusion and initial evaluation, and the remaining four years to follow-up.</p> <p><b>Setting</b>: The study will be carried out in the urban primary care setting.</p> <p><b>Study population</b>: Consecutive sampling will be used to include patients diagnosed with type 2 diabetes between 20-80 years of age. A total of 110 patients meeting all the inclusion criteria and none of the exclusion criteria will be included.</p> <p><b>Measurements</b>: Patient age and sex, family and personal history of cardiovascular disease, and cardiovascular risk factors. Height, weight, heart rate and abdominal circumference. Laboratory tests: hemoglobin, lipid profile, creatinine, microalbuminuria, glomerular filtration rate, blood glucose, glycosylated hemoglobin, blood insulin, fibrinogen and high sensitivity C-reactive protein. Clinical and 24-hour ambulatory (home) blood pressure monitoring and self-measured blood pressure. Common carotid artery ultrasound for the determination of mean carotid intima-media thickness. Electrocardiogram for assessing left ventricular hypertrophy. Ankle-brachial index. Retinal vascular study based on funduscopy with non-mydriatic retinography and evaluation of pulse wave morphology and pulse wave velocity using the SphygmoCor system. The medication used for diabetes, arterial hypertension and hyperlipidemia will be registered, together with antiplatelet drugs.</p> <p>Discussion</p> <p>The results of this study will help to know and quantify the prognostic value of central arterial pressure and pulse wave velocity in relation to the evolution of the subclinical target organ damage markers and the possible incidence of cardiovascular events in patients with type 2 diabetes mellitus.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov Identifier: NCT01065155</p
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