666 research outputs found

    Soliton Turbulence in Shallow Water Ocean Surface Waves

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    We analyze shallow water wind waves in Currituck Sound, North Carolina and experimentally confirm, for the first time, the presence of solitonsoliton turbulenceturbulence in ocean waves. Soliton turbulence is an exotic form of nonlinear wave motion where low frequency energy may also be viewed as a densedense solitonsoliton gasgas, described theoretically by the soliton limit of the Korteweg-deVries (KdV) equation, a completelycompletely integrableintegrable solitonsoliton systemsystem: Hence the phrase "soliton turbulence" is synonymous with "integrable soliton turbulence." For periodic/quasiperiodic boundary conditions the ergodicergodic solutionssolutions of KdV are exactly solvable by finitefinite gapgap theorytheory (FGT), the basis of our data analysis. We find that large amplitude measured wave trains near the energetic peak of a storm have low frequency power spectra that behave as ω1\sim\omega^{-1}. We use the linear Fourier transform to estimate this power law from the power spectrum and to filter denselydensely packedpacked solitonsoliton wavewave trainstrains from the data. We apply FGT to determine the solitonsoliton spectrumspectrum and find that the low frequency ω1\sim\omega^{-1} region is solitonsoliton dominateddominated. The solitons have randomrandom FGTFGT phasesphases, a solitonsoliton randomrandom phasephase approximationapproximation, which supports our interpretation of the data as soliton turbulence. From the probabilityprobability densitydensity ofof thethe solitonssolitons we are able to demonstrate that the solitons are densedense inin timetime and highlyhighly nonnon GaussianGaussian.Comment: 4 pages, 7 figure

    Nesting of the Aplomado Falcon (<i>Falco f. femoralis </i> )in San Luis province

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    In this paper we describe the activity of a nesting pair of Aplomado Falcons (Falco f.femoralis) during the first days of the nestling period. The nest was found in a Chañar tree (Geoffroea decorticans) at a heíght of 4.5 m in San Luis province. The female remained at the nest 94.14% of the observation time (brooding: 86.90%) and fed thc nestlings with arate of 0.47 items/h. Feeding periods lasted in average 560 sec (Ra: 360-780 scc; n:9). The male was seen on the nest 1.28% of the obscrvation time and brought prcy with a frequency of 0.41 items/h. Information of nest and nestling characteristics, territory, defense, caching behavior and vocalizations is also given. Finally we provide a compilation about nesting ofthc Aplomado Falcon in Argentina

    Erythema multiforme as first sign of incomplete Kawasaki disease

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    ABSTRACT: Incomplete Kawasaki disease represents a diagnostic challenge for pediatricians. In the absence of classical presentation, the laboratoristic evaluation of systemic inflammation can help in placing the correct diagnosis to promptly start adequate therapy. Erythema multiforme is an acute, self-limiting condition considered to be a hypersensitivity reaction commonly associated with various infections or medications. This aspecific skin condition has been rarely described as a sign of Kawasaki disease. We report on the case of a 4 years old boy presenting high-grade fever associated with erythema multiforme and evidence of systemic inflammation who showed a good response to prompt treatment with intravenous immunoglobulins

    Development of a method for the measurement of primary cilia length in 3D

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    BACKGROUND: Primary cilia length is an important measure of cell and tissue function. While accurate length measurements can be calculated from cells in 2D culture, measurements in tissue or 3D culture are inherently difficult due to optical distortions. This study uses a novel combination of image processing techniques to rectify optical distortions and accurately measure cilia length from 3D images. METHODS: Point spread functions and experimental resolutions were calculated from subresolution microspheres embedded in 3D agarose gels for both wide-field fluorescence and confocal laser scanning microscopes. The degree of axial smearing and spherical aberration was calculated from xy:xz diameter ratios of 3D image data sets of 4 μm microspheres that had undergone deconvolution and/or Gaussian blurring. Custom-made 18 and 50 μm fluorescent microfibers were also used as calibration objects to test the suitability of processed image sets for 3D skeletonization. Microfiber length in 2D was first measured to establish an original population mean. Fibers were then embedded in 3D agarose gels to act as ciliary models. 3D image sets of microfibers underwent deconvolution and Gaussian blurring. Length measurements within 1 standard deviation of the original 2D population mean were deemed accurate. Finally, the combined method of deconvolution, Gaussian blurring and skeletonization was compared to previously published methods using images of immunofluorescently labeled renal and chondrocyte primary cilia. RESULTS: Deconvolution significantly improved contrast and resolution but did not restore the xy:xz diameter ratio (0.80). Only the additional step of Gaussian blurring equalized xy and xz resolutions and yielded a diameter ratio of 1.02. Following image processing, skeletonization successfully estimated microfiber boundaries and allowed reliable and repeatable measurement of fiber lengths in 3D. We also found that the previously published method of calculating length from 2D maximum projection images significantly underestimated ciliary length. CONCLUSIONS: This study used commercial and public domain image processing software to rectify a long-standing problem of 3D microscopy. We have shown that a combination of deconvolution and Gaussian blurring rectifies optical distortions inherent in 3D images and allows accurate skeletonization and length measurement of microfibers and primary cilia that are bent or curved in 3D space

    Evaluation of cephalometric, hormonal and enzymatic parameters in young obese subjects

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    Aim The aim of the present investigation was to analyse cephalometric skeletal structures and hormonal and enzymatic parameters in young obese subjects in comparison with those of normal weight subjects. Materials and methods The whole sample consisted of 50 Caucasian patients (28 males and 22 females) whose lateral radiographs, laboratory hormonal and enzymatic analyses were already available. The test group included 25 obese patients (11 females and 14 males, average age: 9.8 ± 2.11 years old), while the control group included 25 normal weight subjects matched for age and sex (11 females and 14 males, 9.9 ± 2.5 years old). Data were statistically analysed: Student’s t-test for independent samples was adopted and the level of significance was set at: p< 0.05. Results As regards cephalometric records, the anterior cranial base length was significantly greater in the test group (S-N: 69.9 ± 4 mm) compared to the controls (S-N: 68.1 ± 2.7 mm). Moreover, the maxillary lenght was higher in the test group (Pm-A: 48.5 ± 2.5 mm ) in comparison to the control group (Pm-A: 46.1 ± 1.9 mm). As regards skeletal class and vertical dimension, no significant differences were found between the two groups, with the exception of the intermaxillary plane angle, which was significantly lower in the obese subjects in comparison to the controls. Laboratory analysis showed significant (p <0.05) higher levels of leptin and insulin in the test group in comparison with control subjects. Furthermore, LH, FSH, IGF-1 values were significantly (p <0.05) lower in the test group in comparison with the control group. Conclusion Obese subjects exhibited an increase of some craniofacial parameters and alteration of some laboratory parameters that may be involved in the process of skeletal maturation, in comparison to normal weight subjects. These findings may be of interest in orthodontics, as young obese subjects may need a different orthodontic treatment plan in comparison to Evaluation normal weight subjects of the same age

    Nasal immunization with the c-terminal domain of bcla3 induced specific igg production and attenuated disease symptoms in mice infected with clostridioides difficile spores

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    Clostridioides difficile is a Gram-positive, spore-forming bacterium that causes a severe intestinal infection. Spores of this pathogen enter in the human body through the oral route, interact with intestinal epithelial cells and persist in the gut. Once germinated, the vegetative cells colonize the intestine and produce toxins that enhance an immune response that perpetuate the disease. Therefore, spores are major players of the infection and ideal targets for new therapies. In this context, spore surface proteins of C. difficile, are potential antigens for the development of vaccines targeting C. difficile spores. Here, we report that the C-terminal domain of the spore surface protein BclA3, BclA3CTD, was identified as an antigenic epitope, over-produced in Escherichia coli and tested as an immunogen in mice. To increase antigen stability and efficiency, BclA3CTD was also exposed on the surface of B. subtilis spores, a mucosal vaccine delivery system. In the experimental conditions used in this study, free BclA3CTD induced antibody production in mice and attenuated some C. difficile infection symptoms after a challenge with the pathogen, while the spore-displayed antigen resulted less effective. Although dose regimen and immunization routes need to be optimized, our results suggest BclA3CTD as a potentially effective antigen to develop a new vaccination strategy targeting C. difficile spores

    Are white storks addicted to junk food? Impacts of landfill use on the movement and behaviour of resident white storks (Ciconia ciconia) from a partially migratory population

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    Background: The migratory patterns of animals are changing in response to global environmental change with many species forming resident populations in areas where they were once migratory. The white stork (Ciconia ciconia) was wholly migratory in Europe but recently guaranteed, year-round food from landfill sites has facilitated the establishment of resident populations in Iberia. In this study 17 resident white storks were fitted with GPS/GSM data loggers (including accelerometer) and tracked for 9.1 ± 3.7 months to quantify the extent and consistency of landfill attendance by individuals during the non-breeding and breeding seasons and to assess the influence of landfill use on daily distances travelled, percentage of GPS fixes spent foraging and non-landfill foraging ranges. Results: Resident white storks used landfill more during non-breeding (20.1 % ± 2.3 of foraging GPS fixes) than during breeding (14.9 % ± 2.2). Landfill attendance declined with increasing distance between nest and landfill in both seasons. During non-breeding a large percentage of GPS fixes occurred on the nest throughout the day (27 % ± 3.0 of fixes) in the majority of tagged storks. This study provides first confirmation of year-round nest use by resident white storks. The percentage of GPS fixes on the nest was not influenced by the distance between nest and the landfill site. Storks travelled up to 48.2 km to visit landfills during non-breeding and a maximum of 28.1 km during breeding, notably further than previous estimates. Storks nesting close to landfill sites used landfill more and had smaller foraging ranges in non-landfill habitat indicating higher reliance on landfill. The majority of non-landfill foraging occurred around the nest and long distance trips were made specifically to visit landfill. Conclusions: The continuous availability of food resources on landfill has facilitated year-round nest use in white storks and is influencing their home ranges and movement behaviour. White storks rely on landfill sites for foraging especially during the non-breeding season when other food resources are scarcer and this artificial food supplementation probably facilitated the establishment of resident populations. The closure of landfills, as required by EU Landfill Directives, will likely cause dramatic impacts on white stork populations

    Nasal immunization with the c-terminal domain of bcla3 induced specific igg production and attenuated disease symptoms in mice infected with clostridioides difficile spores

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    Indexación: Scopus.Clostridioides difficile is a Gram-positive, spore-forming bacterium that causes a severe intestinal infection. Spores of this pathogen enter in the human body through the oral route, interact with intestinal epithelial cells and persist in the gut. Once germinated, the vegetative cells colonize the intestine and produce toxins that enhance an immune response that perpetuate the disease. Therefore, spores are major players of the infection and ideal targets for new therapies. In this context, spore surface proteins of C. difficile, are potential antigens for the development of vaccines targeting C. difficile spores. Here, we report that the C-terminal domain of the spore surface protein BclA3, BclA3CTD, was identified as an antigenic epitope, over-produced in Escherichia coli and tested as an immunogen in mice. To increase antigen stability and efficiency, BclA3CTD was also exposed on the surface of B. subtilis spores, a mucosal vaccine delivery system. In the experimental conditions used in this study, free BclA3CTD induced antibody production in mice and attenuated some C. difficile infection symptoms after a challenge with the pathogen, while the spore-displayed antigen resulted less effective. Although dose regimen and immunization routes need to be optimized, our results suggest BclA3CTD as a potentially effective antigen to develop a new vaccination strategy targeting C. difficile spores. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.https://www.mdpi.com/1422-0067/21/18/669

    Proton-air cross section measurement with the ARGO-YBJ cosmic ray experiment

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    The proton-air cross section in the energy range 1-100 TeV has been measured by the ARGO-YBJ cosmic ray experiment. The analysis is based on the flux attenuation for different atmospheric depths (i.e. zenith angles) and exploits the detector capabilities of selecting the shower development stage by means of hit multiplicity, density and lateral profile measurements at ground. The effects of shower fluctuations, the contribution of heavier primaries and the uncertainties of the hadronic interaction models, have been taken into account. The results have been used to estimate the total proton-proton cross section at center of mass energies between 70 and 500 GeV, where no accelerator data are currently available.Comment: 14 pages, 9 figure
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