615 research outputs found

    Star formation history of the post-collisional Cartwheel galaxy using Astrosat/UVIT FUV images

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    We present the results obtained by analysing new Astrosat/UVIT far ultraviolet (FUV) image of the collisional-ring galaxy Cartwheel. The FUV emission is principally associated with the star-forming outer ring, with no UV detection from the nucleus and inner ring. A few sources are detected in the region between the inner and the outer rings, all of which lie along the spokes. The FUV fluxes from the detected sources are combined with aperture-matched multi-band photometric data from archival images to explore the post-collision star formation history of the Cartwheel. The data were corrected for extinction using Av derived from the Balmer decrement ratios and commonly used extinction curves. We find that the ring regions contain stellar populations of wide range of ages, with the bulk of the FUV emission coming from non-ionizing stars, formed over the last 20 to 150 Myr, that are ~25 times more massive than the ionizing populations. On the other hand, regions belonging to the spokes have negligible current star formation, with the age of the dominant older population systematically increasing as its distance from the outer ring increases. The presence of populations of a wide range of ages in the ring suggests that the stars formed in the wave in the past were dragged along it to the current position of the ring. We derive an average steady star formation rate, SFR=5 Msun/yr, over the past 150 Myr, with an increase to ~18 Msun/yr in the recent 10 Myr.Comment: 16 pages, to appear in MNRA

    Anticuerpos de Trypanosoma cruzi, Leishmania mexicana y Leishmania braziliensis en perros domiciliados de Tabasco, México

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    Objective. To determine Trypanosoma cruzi (T. cruzi), Leishmania mexicana (L.mexicana) and Leishmania braziliensis (L.braziliensis) circulating antibodies in dogs from Chontalpa region in Tabasco, Mexico using ELISA diagnostic techniques Fe-SOD and Western blot. Materials and methods. For this study, 119 serums were obtained from domiciled dogs. Serums were tested for antibodies against T. cruzi, L. mexicana and L. braziliensis, using ELISA and Western Blot sod as diagnostic test. The antigenic fraction used in both tests was the Fe-SOD excreted by the species of Leishmania and Trypanosoma. Results. The obtained frequency in this study was 3.36% for T. cruzi, 9.24% for L. mexicana and 10.08% for L. braziliensis. Conclusions. The present study has demonstrated the presence of antibodies to these parasites in Chontalpa region from Tabasco, Mexico.Objetivo. Determinar la frecuencia de anticuerpos circulantes de Trypanosoma cruzi (T. cruzi), Leishmania mexicana (L. mexicana) y Leishmania braziliensis (L. braziliensis) en una población de perros usando ELISA Fe-SOD y Western blot en la región Chontalpa del estado de Tabasco, México. Materiales y métodos. Para este estudio se obtuvieron 119 sueros de perros domiciliados, con el consentimiento previo de los propietarios. Los sueros fueron analizados para detectar anticuerpos contra T. cruzi, L. mexicana, y L. braziliensis, usando como prueba diagnóstica ELISA-sod y Western Blot. La fracción antigénica utilizada en las dos pruebas fue la Fe-SOD excretada por las especies de Trypanosoma y Leishmania. Resultados. La frecuencia obtenida en este estudio fue de 3.36% para T. cruzi, 9.24% para L. mexicana y 10.08% L. braziliensis. Conclusiones. El presente estudio demostró la presencia de anticuerpos para estos parásitos en la región Chontalpa del estado de Tabasco, México

    Wolf-Rayet stars in the Antennae unveiled by MUSE

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    We present the analysis of archival Very Large Telescope (VLT) Multi Unit Spectroscopic Explorer (MUSE) observations of the interacting galaxies NGC 4038/39 (a.k.a. the Antennae) at a distance of 18.1 Mpc. Up to 38 young star-forming complexes with evident contribution from Wolf-Rayet (WR) stars are unveiled. We use publicly available templates of Galactic WR stars in conjunction with available photometric extinction measurements to quantify and classify the WR population in each star-forming region, on the basis of its nearly Solar oxygen abundance. The total estimated number of WR stars in the Antennae is 4053 ±\pm 84, of which there are 2021 ±\pm 60 WNL and 2032 ±\pm 59 WC-types. Our analysis suggests a global WC to WN-type ratio of 1.01 ±\pm 0.04, which is consistent with the predictions of the single star evolutionary scenario in the most recent BPASS stellar population synthesis models.Comment: 20 pages, 16 figures, 5 tables; accepted to MNRA

    Severity of cardiomyopathy associated with adenine nucleotide translocator-1 deficiency correlates with mtDNA haplogroup

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    Mutations of both nuclear and mitochondrial DNA (mtDNA)-encoded mitochondrial proteins can cause cardiomyopathy associated with mitochondrial dysfunction. Hence, the cardiac phenotype of nuclear DNA mitochondrial mutations might be modulated by mtDNA variation. We studied a 13-generation Mennonite pedigree with autosomal recessive myopathy and cardiomyopathy due to an SLC25A4 frameshift null mutation (c.523delC, p.Q175RfsX38), which codes for the heart-muscle isoform of the adenine nucleotide translocator-1. Ten homozygous null (adenine nucleotide translocator-1(-/-)) patients monitored over a median of 6 years had a phenotype of progressive myocardial thickening, hyperalaninemia, lactic acidosis, exercise intolerance, and persistent adrenergic activation. Electrocardiography and echocardiography with velocity vector imaging revealed abnormal contractile mechanics, myocardial repolarization abnormalities, and impaired left ventricular relaxation. End-stage heart disease was characterized by massive, symmetric, concentric cardiac hypertrophy; widespread cardiomyocyte degeneration; overabundant and structurally abnormal mitochondria; extensive subendocardial interstitial fibrosis; and marked hypertrophy of arteriolar smooth muscle. Substantial variability in the progression and severity of heart disease segregated with maternal lineage, and sequencing of mtDNA from five maternal lineages revealed two major European haplogroups, U and H. Patients with the haplogroup U mtDNAs had more rapid and severe cardiomyopathy than those with haplogroup H

    WPŁYW WYCIĄGÓW Z ROŚLIN BODZISZKOWATYCH NA BIELINKA KAPUSTNIKA

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    The conducted studies comprised the analyses of activity of extracts derived from selected plants of the Geranium family on some processes of large white butterfly (Pieris brassicae) development (oviposition, survival of eggs and caterpillar feeding). The results proved that all tested extracts showed activity against large white butterfly. Geranium pratense L. and Geranium senquineum L. showed better activity than other Geranium plants. Water extracts from these species protected cabbage plants against laying eggs, while applied on eggs caused their mortality. Alcohol and water extracts from G. pratense L. and water extracts from G. senquineum L. increased an amount of food put on mass gain of caterpillars.Analizowano oddziaływanie ekstraktów uzyskanych z wybranych roślin z rodziny Bodziszkowate na: rozwój bielinka kapustnika (przebieg składania jaj, przeżywalność jaj oraz na żerowanie gąsienic). Stwierdzono, że wszystkie testowane wyciągi, wykazywały aktywne działanie w stosunku do bielinka kapustnika. Szczególnie wyróżniały się bodziszek łąkowy i bodziszek czerwony. Wodne wyciągi z tych roślin chroniły rośliny kapusty przed składaniem na nie jaj przez samice, a zastosowane na jaja, powodowały ich zamieranie. Alkoholowy i wodny wyciąg z bodziszka łąkowego oraz wyciąg wodny z bodziszka czerwonego wpływały na zwiększenie ilości pokarmu zużywanego na przyrost masy ciała gąsienic

    Beyond the required LISA free-fall performance: new LISA pathfinder results down to 20  μHz

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    In the months since the publication of the first results, the noise performance of LISA Pathfinder has improved because of reduced Brownian noise due to the continued decrease in pressure around the test masses, from a better correction of noninertial effects, and from a better calibration of the electrostatic force actuation. In addition, the availability of numerous long noise measurement runs, during which no perturbation is purposely applied to the test masses, has allowed the measurement of noise with good statistics down to 20  μHz. The Letter presents the measured differential acceleration noise figure, which is at (1.74±0.05)  fm s^{-2}/sqrt[Hz] above 2 mHz and (6±1)×10  fm s^{-2}/sqrt[Hz] at 20  μHz, and discusses the physical sources for the measured noise. This performance provides an experimental benchmark demonstrating the ability to realize the low-frequency science potential of the LISA mission, recently selected by the European Space Agency

    Neuropathic Pain in Dogs and Cats: Current Evaluation and Treatment Perspectives: Review

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    Abstract: During the past decade, the number of scientific papers on the recognition and multimodal management of pain in small animals increased exponentially. However, the variable of neuropathic pain, or adaptive disorder, has not yet been characterized completely. Its genesis is related to several diseases and injuries of the nervous system that change the neuroanatomical structures that participate in pain processing. Finding novel neurobiological mechanisms and the development of techniques for diagnosis and treatment in Human Medicine, are opening great opportunities for research and the understanding of neuropathic pain in pets

    Validation of bioelectrical impedance analysis for body composition assessment in children with obesity aged 8-14y

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    BACKGROUND & AIMS: The aim was to generate a predictive equation to assess body composition (BC) in children with obesity using bioimpedance (BIA), and avoid bias produced by different density levels of fat free mass (FFM) in this population. METHODS: This was a cross-sectional validation study using baseline data from a randomized intervention trial to treat childhood obesity. Participants were 8 to 14y (n = 315), underwent assessments on anthropometry and BC through Air Displacement Plethysmography (ADP), Dual X-Ray Absorptiometry and BIA. They were divided into a training (n = 249) and a testing subset (n = 66). In addition, the testing subset underwent a total body water assessment using deuterium dilution, and thus obtained results for the 4-compartment model (4C). A new equation to estimate FFM was created from the BIA outputs by comparison to a validated model of ADP adjusted by FFM density in the training subset. The equation was validated against 4C in the testing subset. As reference, the outputs from the BIA device were also compared to 4C. RESULTS: The predictive equation reduced the bias from the BIA outputs from 14.1% (95%CI: 12.7, 15.4) to 4.6% (95%CI: 3.8, 5.4) for FFM and from 18.4% (95%CI: 16.9, 19.9) to 6.4% (95% CI: 5.3, 7.4) for FM. Bland-Altman plots revealed that the new equation significantly improved the agreement with 4C; furthermore, the observed trend to increase the degree of bias with increasing FM and FFM also disappeared. CONCLUSION: The new predictive equation increases the precision of BC assessment using BIA in children with obesity
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