Rapidly oscillating Ap stars are unique objects in the potential they offer to study the interplay between a number of important physical phenomena, in particular, pulsations, magnetic fields, ...diffusion and convection. Nevertheless, the simple understanding of how the observed pulsations are excited in these stars is still in progress. In this work, we perform a test to what is possibly the most widely accepted excitation theory for this class of stellar pulsators. The test is based on the study of a subset of members of this class for which stringent data on the fundamental parameters are available thanks to interferometry. For three out of the four stars considered in this study, we find that linear, non-adiabatic models with envelope convection suppressed around the magnetic poles can reproduce well the frequency region where oscillations are observed. For the fourth star in our sample no agreement is found, indicating that a new excitation mechanism must be considered. For the three stars whose observed frequencies can be explained by the excitation models under discussion, we derive the minimum angular extent of the region where convection must be suppressed. Finally, we find that the frequency regions where modes are expected to be excited in these models are very sensitive to the stellar radius. This opens the interesting possibility of determining this quantity and related ones, such as the effective temperature or luminosity, from comparison between model predictions and observations, in other targets for which these parameters are not well determined.
Purpose
We aimed to study the relationship between aging and increased parathyroid hormone (PTH) values.
Methods
We performed a retrospective cross-sectional study with data from patients who ...underwent outpatient PTH measurements performed by a second-generation electrochemiluminescence immunoassay. We included patients over 18 years of age with simultaneous PTH, calcium, and creatinine measurements and 25-OHD measured within 30 days. Patients with glomerular filtration rate < 60 mL/min/1.73 m
2
, altered calcemia, 25-OHD level < 20 ng/mL, PTH values > 100 pg/mL or using lithium, furosemide or antiresorptive therapy were excluded. Statistical analyses were performed using the RefineR method.
Results
Our sample comprised 263,242 patients for the group with 25-OHD ≥ 20 ng/mL, that included 160,660 with 25-OHD ≥ 30 ng/mL. The difference in PTH values among age groups divided by decades was statistically significant (p < 0.0001), regardless of 25-OHD values, ≥ 20 or ≥ 30 ng/mL. In the group with 25-OHD ≥ 20 ng/mL and more than 60 years, the PTH values were 22.1–84.0 pg/mL, a different upper reference limit from the reference value recommended by the kit manufacturer.
Conclusion
We observed a correlation between aging and PTH increase, when measured by a second-generation immunoassay, regardless of vitamin D levels, if greater than 20 ng/mL, in normocalcemic individuals without renal dysfunction.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract The tambaqui (Colossoma macropomum) is a species of great economic importance for fish farming in the Brazilian Amazon, and acanthocephaliasis caused by Neoechinorhynchus buttnerae (Golvan ...1956) represents an obstacle to its production due to it causing severe morphological damage to the intestinal mucosa, thus impairing the absorption of nutrients and causing weight loss in the fish. Therefore, the establishment of in vitro protocols for evaluation of anthelmintic drugs is the first step to development of effective measures for in vivo control of this endoparasite. The present study evaluated the in vitro survival of N. buttnerae maintained in Eagle’s minimum essential medium under different culture conditions. Three assays were carried out to evaluate whether temperature, supplementation with the antibiotics penicillin and streptomycin, and culture medium replacement or no replacement would influence the motility and morphology of the acanthocephalans. The results of the Kaplan-Meier analysis indicated that the use of culture in minimum essential medium together with penicillin and streptomycin prolonged the parasite’s survival when kept at temperatures of 24 °C or 28 °C. We describe herein for first time an alternative protocol that is ideal for the in vitro culture of N. buttnerae. As such, this protocol ensures greater reliability in further in vitro studies with N. buttnerae.
Resumo O tambaqui (Colossoma macropomum) é uma espécie de grande importância econômica para a piscicultura na Amazônia brasileira, e a acantocefalose causada por Neoechinorhynchus buttnerae (Golvan 1956) representa um obstáculo à sua produção por causar severos danos morfológicos à mucosa intestinal, prejudicando a absorção de nutrientes e causando perda de peso nos peixes. Assim, o estabelecimento de protocolos in vitro para avaliação de fármacos anti-helmínticos é o primeiro passo para o desenvolvimento de medidas eficazes de controle in vivo destes endoparasitas. O presente estudo avaliou a sobrevivência in vitro de N. buttnerae mantido em meio essencial mínimo de Eagle sob diferentes condições de cultivo. Três ensaios foram realizados para avaliar se a temperatura, a suplementação com os antibióticos penicilina e estreptomicina e a substituição ou não do meio nutriente influenciariam a motilidade e a morfologia dos acantocéfalos. Os resultados da análise de Kaplan-Meier indicaram que o uso do meio essencial mínimo suplementado com penicilina e estreptomicina prolongou a sobrevivência do parasito quando mantido em temperaturas de 24 °C ou 28 °C. Este estudo descreve pela primeira vez um protocolo alternativo que é ideal para o cultivo in vitro de N. buttnerae. Este protocolo garante maior confiabilidade em ensaios in vitro com N. buttnerae.
•Social defeat stress induces persistent mechanical and chemical hyperalgesia in mice.•Voluntary running wheel exercise is more effective than fluoxetine reversing the SDS-induced persistent ...hyperalgesia.•Voluntary running wheel exercise and fluoxetine are effective reversing SDS-induced social avoidance.•Voluntary running wheel exercise is an effective tool preventing both hyperalgesia and social avoidance induced by SDS.
Major depressive disorders (MDD) and chronic pain (CP) affect significant portion of the world's population and have high comorbidity rate. Social defeat stress (SDS) model was standardized in mice and can trigger depressive-like behavior and chronic pain. Based especially on clinical trials showing an effective preventive and therapeutic effect of physical exercise on CP and symptoms associated with MDD, this study aimed to investigate if the voluntary running wheel exercise can exert these effects in mice submitted to the 10-day SDS protocol, using fluoxetine as positive control. For this, we ran two set of experiments: in the first set mice started performing voluntary running wheel exercise after submitted to SDS and, in the second set, mice performed voluntary running wheel exercise before and during SDS. Mechanical and chemical hyperalgesia was analyzed through electronic von Frey and capsaicin test, respectively. Depressive-like behavior was assessed through social interaction test. Our results showed that the voluntary running wheel exercise was more effective than fluoxetine reversing the SDS-induced persistent hyperalgesia and both, fluoxetine and voluntary running wheel exercise, was effective reversing SDS-induced social avoidance. Also, voluntary running wheel exercise is an effective tool preventing both hyperalgesia and social avoidance induced by SDS. To the best of our knowledge, this was the first study using physical exercise as a therapeutic and preventive tool for chronic pain and depressive-like behavior simultaneously induced by social stress.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Particular diagnostic tools may isolate the signature left on the oscillation frequencies by the presence of a small convective core. Their frequency derivative is expected to provide information ...about convective core's properties and stellar age. The main goal of this work is to study the potential of the diagnostic tools with regard to the inference of stellar age and stellar core's properties. For that, we computed diagnostic tools and their frequency derivatives from the oscillation frequencies of main-sequence models with masses between 1.0 and 1.6 M⊙ and with different physics. We considered the dependence of the diagnostic tools on stellar age and on the size of the relative discontinuity in the squared sound speed at the edge of the convectively unstable region. We find that the absolute value of the frequency derivatives of the diagnostic tools increases as the star evolves on the main sequence. The fraction of stellar main-sequence evolution for models with masses >1.2 M⊙ may be estimated from the frequency derivatives of two of the diagnostic tools. For lower mass models, constraints on the convective core's overshoot can potentially be derived based on the analysis of the same derivatives. For at least 35 per cent of our sample of stellar models, the frequency derivative of the diagnostic tools takes its maximum absolute value on the frequency range where observed oscillations may be expected.
Precise stellar parameters (effective temperature, surface gravity, metallicity, stellar mass, and radius) are crucial for several reasons, amongst which are the precise characterization of orbiting ...exoplanets and the correct determination of galactic chemical evolution. The surface gravity, however, is usually not well constrained with spectroscopy. We use two different samples of FGK dwarfs to study the effect of the stellar surface gravity on the precise spectroscopic determination of the other atmospheric parameters. Furthermore, we present a straightforward formula for correcting the spectroscopic surface gravities derived by our method and with our linelists. We find first that, despite some minor trends, the effective temperatures and metallicities for FGK dwarfs derived with the described method and linelists are, in most cases, only affected within the errorbars by using different values for the surface gravity, even for very large differences in surface gravity, so they can be trusted. Secondly, we find that the spectroscopic surface gravity can easily be corrected to a more accurate value using a linear function with the effective temperature.
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FMFMET, NUK, UL, UM, UPUK
Abstract Objective: Our goal was to conduct the generation and piloting of a discriminative and evaluative tool for pediatric post-thrombotic syndrome. Methods: We followed a formative model for the ...development of the tool, focusing on the signs/symptoms (items) that define post-thrombotic syndrome. For item generation, pediatric thrombosis experts and subjects diagnosed with extremity post-thrombotic syndrome during childhood nominated items. In the piloting phase, items were cross-sectionally measured in children with limb deep vein thrombosis to examine the performance of the items. Result: Twenty-three experts and 16 subjects listed 34 items, which were then measured in 140 subjects with previous diagnosis of limb deep vein thrombosis (70 upper extremity and 70 lower extremity). The items with strongest correlation with post-thrombotic syndrome severity and largest area under the curve were pain (in older children), paresthesia, and swollen limb for the upper extremity group, and pain (in older children), tired limb, heaviness, tightness and paresthesia for the lower extremity group. Conclusion: Diagnostic properties and correlation with post-thrombotic syndrome severity of the different signs and symptoms varied according to the assessed venous territory. The information gathered in this study will help experts decide which item should be considered for inclusion in the new tool.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In addition to its search for extrasolar planets, the NASA Kepler mission provides exquisite data on stellar oscillations. We report the detections of oscillations in 500 solar-type stars in the ...Kepler field of view, an ensemble that is large enough to allow statistical studies of intrinsic stellar properties (such as mass, radius, and age) and to test theories of stellar evolution. We find that the distribution of observed masses of these stars shows intriguing differences to predictions from models of synthetic stellar populations in the Galaxy.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Summary
The breadth‐first search procedure is an algorithm that traverses the vertices of a graph, determining the distance from each vertex to the initial vertex. The distance is infinite for a ...non‐reachable vertex from the starting vertex. Despite having an efficient serial version, this important algorithm is irregular, making its effective parallel implementation a daunting task. This paper shows the results of an OpenMP‐based implementation of the breadth‐first search procedure using the bag data structure. Furthermore, the code relied on the C++ programming language. This paper reimplements an existing proposal coded using the Cilk++ programming language. The experiments relied on 32 strongly connected graphs and 31 disconnected graphs in executions performed on two machines. The first machine contained 28 cores and two threads per core. The second machine comprised 48 processing cores, with hyperthreading disabled. Regarding the serial version, the parallel implementation yielded a speedup of up to 20× when using 28 processing cores and up to 25× when using 56 threads in tests performed on a machine with the first generation of Intel® Xeon® Scalable processors. Furthermore, the new parallel implementation yielded speedups of up to 45× when using 48 cores in experiments performed on a machine with the second generation of Intel® Xeon® Scalable processors.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Aims
In order to improve the quality and to create a biological basis for obtainment of the protected denomination of origin (PDO), indigenous yeast were isolated and characterized for use in Salinas ...city (the Brazilian region of quality cachaça production).
Material and methods
Seven thousand and two hundred yeast colonies from 15 Salinas city distilleries were screened based on their fermentative behaviour and the physicochemical composition of cachaça. Molecular polymorphic analyses were performed to characterize these isolates.
Results
Two Saccharomyces cerevisiae strains (nos. 678 and 680) showed appropriate characteristics to use in the cachaça production: low levels of acetaldehyde and methanol, and high ethyl lactate/ethyl acetate ratio respectively. They also presented polymorphic characteristics more closely related between themselves even when compared to other strains from Salinas.
Conclusions
The application of selected yeast to cachaça production can contribute for the improvement of the quality product as well as be used as a natural marker for PDO.
Significance and Impact of the Study
This study suggests that the use of selected yeast strains could contribute to obtain a cachaça similar to those produced traditionally, while getting wide acceptation in the market, yet presenting more homogeneous organoleptic characteristics, and thus contributing to the PDO implementation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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