Phase locking a clock oscillator to a coherent atomic ensemble

The sensitivity of an atomic interferometer increases when the phase evolution of its quantum superposition state is measured over a longer interrogation interval. In practice, a limit is set by the measurement process, which returns not the phase, but its projection in terms of population difference on two energetic levels. The phase interval over which the relation can be inverted is thus limited to the interval $[-\pi/2,\pi/2]$; going beyond it introduces an ambiguity in the read out, hence a sensitivity loss. Here, we extend the unambiguous interval to probe the phase evolution of an atomic ensemble using coherence preserving measurements and phase corrections, and demonstrate the phase lock of the clock oscillator to an atomic superposition state. We propose a protocol based on the phase lock to improve atomic clocks under local oscillator noise, and foresee the application to other atomic interferometers such as inertial sensors.Comment: 9 pages, 7 figure

Stellar Populations in Barred Galaxies

We developed an iterative technique to better characterize stellar populations and the central activity of barred galaxies using evolutionary synthesis codes and OASIS data. The case of NGC5430 is presented here. Our results are reinforcing the role played by the bar and nuclear structures for the evolution of galaxies.Comment: 2 pages, 1 figure, to be published in the proceedings of IAU Symp. 262 "Stellar Populations - Planing for the Next Decate" (Aug. 2009

Intrinsic and extrinsic attributes related to the influence of growing altitude on consumer acceptability and sensory perception of fresh apple

BACKGROUND: Growing altitude might have an effect on the quality of fresh apple and therefore on the perception of sensory attributes and on acceptance by consumers. On the other hand, extrinsic information provided to the consumer might affect consumer acceptability and sensory perception of the fruit''s main quality traits. The main objective of this work was to study the effect of the growing altitude on the physico-chemical attributes (soluble solid content (SSC), flesh firmness, fruit weight (g), and titratable acidity (TA)), consumer acceptability, and perception of the main sensory attributes (sweetness, acidity and texture) of two reference apple cultivars (‘Golden D.’ and ‘Reineta’) by using a panel of 195 consumers. A secondary objective was to study whether extrinsic information about cultivar and growing place have an effect on the consumer perception and acceptance of fresh apple. RESULTS: Significant effects on physico-chemical and sensory attributes were found for ‘Golden D.’ and ‘Reineta’ apple cultivars due to the growing altitude, and they were perceived by consumers. Moreover, extrinsic information about the cultivar and the growing site influenced consumers'' sensory perceptions significantly. CONCLUSIONS: This work demonstrated that differences between apple fruit grown at different altitudes can be perceived by consumers. We demonstrated the importance of providing consumers with information about the cultivar and the growing place to increase their acceptance and support local produce. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry

Nanopartículas Poliméricas en Dermocosmética

Indexación: Web of Science; Scielo.Recent advances in the fields of biomaterials and nanotechnology have allowed the development of advanced nanoparticles for biomedical applications. Despite a vast number of nanostructures such as liposomes, solid­lipid nanocapsules, polymeric and hybrid lipid­polymer nanoparticles have been studied as carriers for drug delivery for different pathologies with remarkable promising results; the use of polymeric nanoparticles in dermocosmetic still has not been widely explored. The evolution of cosmetic into the care skin and dermatology represents novel technological challenges. Also, the increasing knowledge about normal skin physiology and advances in nanotechnology provide an attractive environment for the creation of innovative dermocosmetic formulations. In this work, we discuss the state of the art of polymeric nanoparticles formulated for dermocosmetics, its mechanisms of action, and diffusion into the skin.Los recientes avances en el campo de los biomateriales y la nanotecnología han permitido el desarrollo de nanopartículas avanzadas para aplicaciones biomédicas. A pesar de que un gran número de nanoestructuras tales como liposomas, nanocápsulas lípido-sólidas, nanopartículas poliméricas y lípido-polímero híbridas han sido estudiadas como vehículos para la administración de fármacos en diferentes patologías con notables resultados prometedores, el uso de nanopartículas poliméricas en dermocosmética todavía no ha sido ampliamente explorado. La evolución de la cosmética en el cuidado de la piel y la dermatología nos enfrentan a nuevos retos tecnológicos. Además, el aumento de los conocimientos sobre la fisiología de la piel normal y los avances en la nanotecnología proporcionan un entorno atractivo para la creación de formulaciones dermocosméticas innovadoras. En este trabajo se discute el estado del arte de las nanopartículas poliméricas desarrolladas para dermocosmética, sus mecanismos de acción y la difusión en la piel.http://ref.scielo.org/b68hz

Modelling coral calcification accounting for the impacts of coral bleaching and ocean acidification

© Author(s) 2015. Coral reefs are diverse ecosystems that are threatened by rising CO2 levels through increases in sea surface temperature and ocean acidification. Here we present a new unified model that links changes in temperature and carbonate chemistry to coral health. Changes in coral health and population are explicitly modelled by linking rates of growth, recovery and calcification to rates of bleaching and temperature-stress-induced mortality. The model is underpinned by four key principles: the Arrhenius equation, thermal specialisation, correlated up- and down-regulation of traits that are consistent with resource allocation trade-offs, and adaption to local environments. These general relationships allow this model to be constructed from a range of experimental and observational data. The performance of the model is assessed against independent data to demonstrate how it can capture the observed response of corals to stress. We also provide new insights into the factors that determine calcification rates and provide a framework based on well-known biological principles to help understand the observed global distribution of calcification rates. Our results suggest that, despite the implicit complexity of the coral reef environment, a simple model based on temperature, carbonate chemistry and different species can give insights into how corals respond to changes in temperature and ocean acidification

Sex Determination by Observation of Barr Body in Teeth Subjected to High Temperatures

Galdames, IS (reprint author), Univ Talca, Ave Lircay S-N Oficina 104, Valparaiso, Chile.Sex determination is one of the keys in the identification process. A useful histological method for sex determination is the observation of Barr chromatin or Barr body. This study determines the effect of high temperatures on the diagnostic performance of the Barr chromatin observation on teeth. Were used 50 healthy teeth from 25 male and 25 female individuals aged between 14 and 44 years. The teeth were divided into 5 groups (each group with 5 female and 5 male teeth) and were exposed to controlled temperatures of 200, 400, 600, 800, and 1000 degrees C for 5 minutes. The coronal pulp was obtained and the tissue was processed and stained with hematoxylin-eosin. Four histological slides of male and 4 of female individuals were randomly selected, for each temperature level, which were observed by conventional microscopy at 100X magnification, each showing 50 cells per plate. The presence of 1 cell with visible sex chromatin was considered positive for females. It was only possible to evaluate the samples from groups subjected to 200 and 400 degrees C. In the groups analyzed, the test showed 100% accuracy. The average number of cells found to be positive Barr chromatin was 15 (SD 3.9) at 200 degrees C and 11 (SD 2.8) at 400 degrees C. Hence, it was possible to detect the sex at these temperatures by observing chromatin of the Barr body in dental pulp

Gluten contamination in the Canadian commercial oat supply

A growing body of evidence suggests that a majority of people with celiac disease and on a gluten-free diet can safely consume pure oats in moderate amounts; however, previous studies have indicated that the commercial oat supply in other countries, and in Canada to some extent, is contaminated with other grains. This study has confirmed that the commercial oat supply in Canada is heavily contaminated with gluten from other grains. Approximately 88% of the oat samples (n = 133) were contaminated above 20 mg kg−1 and there were no differences between the oat types tested. Only one gluten-free variety of oats was analysed and it consistently provided negative results in all analyses. It is difficult to determine where the contamination originates, but there are possibilities for cross-contamination in the field, in the transport of the grain, in the storage of the grain, and in the milling and packaging facilities. It is clear from this study that only those products that have been certified ‘pure’ oats would be appropriate for a gluten-free diet

Bilateral reversed palmaris longus muscle: a rare anatomical variation

We report a case of bilateral reversed palmaris longus muscle (PLM). The muscle was tendinous in its upper portion and muscular in its lower portion in both arms. This rare variation has been mentioned only once in the literature as a surgical finding. According to the literature, a reversed PLM may cause a compartment syndrome in the wrist area, carpal tunnel, and Guyon’s syndrome. The described variation is also useful to the hand surgeon as a tendon graft, a tendon for transfer, or as an anatomical landmark for operations at this area

Observations of simultaneous sperm release and larval planulation suggest reproductive assurance in the coral Pocillopora acuta

Despite being an extensively studied group of corals, the reproductive biology of the scleractinian genus Pocillopora remains a mystery. Pocillopora acuta has been proposed to exhibit a mixed reproductive mode, sexually producing gametes (sperm and eggs) and asexually brooding larvae simultaneously within a single colony. Here, we report observations of night-time spawning of sperm during the peak monthly larval release period. We offer a new hypothesis for the regulation of sexual and asexual reproduction in the species and posit that sexual reproduction may occur more often than previously suggested. However, the success of internal oocyte fertilization and subsequent zygote development is dependent on sperm making contact with a fertile colony. We hypothesize that asexual development of larvae occurs when sperm is absent, but more extensive genetic, genomic, and histological data are required to determine the pathway by which unfertilized oocytes may develop. We also propose that this mixed mode of reproduction is an adaptation to mating failure, common in sessile marine invertebrates. The reproductive assurance enjoyed by the species may therefore be the key to its ecological and evolutionary persistence