The purpose of this study was to determine the effect of the oral administration of pyridostigmine bromide on indices of heart rate variability (HRV) in healthy young volunteers. Seventeen healthy ...participants (11 men, 6 women; aged 27 +/- 8 y) submitted to a randomized, crossover, double-blind protocol, in which they received 30 mg pyridostigmine bromide (PYR) or placebo orally at 8-hour intervals for 24 hours, on two separate days. Venous blood samples were collected 2 and 24 hours after the first dose for determination of serum cholinesterase activity. Holter tapes were recorded during the 24-hour period and analyzed using a semiautomatic technique to evaluate time- and frequency-domain indices of HRV and to build three-dimensional return maps for later quantification. Symptoms were mild and occurred similarly during administration of PYR and placebo (p = 0.140). Serum cholinesterase activity was reduced by 15% at 2 hours (p = 0.013) and by 14% at 24 hours (p = 0.010) after the first dose of PYR, but not after administration of placebo. Pyridostigmine administration caused a significant increase in the mean 24-hour R-R interval (placebo: 814 +/- 20 msec; PYR: 844 +/- 18 msec; p = 0.003) and in time-domain indices of HRV, such as the standard deviation of all R-R intervals (SDNN; placebo: 151 +/- 9 msec; PYR: 164 +/- 9 msec; p = 0.017), and the percentage of pairs of adjacent R-R intervals differing by more than 50 msec (pNN50; placebo: 12.8 +/- 1.8%; PYR: 13.9 +/- 1.5%; p = 0.029). Pyridostigmine had no significant effect on frequency-domain indices of HRV, but resulted in significant increase in P2, a parasympathetic index derived from the three-dimensional return map (placebo: 93 +/- 13 msec; PYR: 98 +/- 13 ms; p = 0.029). In conclusion, low-dose pyridostigmine reduced mean heart rate and increased HRV during a 24-hour period in healthy young subjects.
Abstract
Novel aspects of engineered nanoparticles offer many advantages for optimising food products and packaging. However, their potential hazards in the gastrointestinal tract require further ...investigation. We evaluated the toxic and inflammatory potential of two types of particles that might become increasingly relevant to the food industry, namely SiO2 and ZnO. The materials were characterised for their morphology, oxidant generation and hydrodynamic behaviour. Cytotoxicity and interleukin-8 mRNA and protein expression were evaluated in human intestinal Caco-2 cells. Particle pretreatment under simulated gastric and intestinal pH conditions resulted in reduced acellular ROS formation but did not influence cytotoxicity (WST-1 assay) or IL-8 expression. However, the differentiation status of the cells markedly determined the cytotoxic potency of the particles. Further research is needed to determine the in vivo relevance of our current observations regarding the role of particle aggregation and the stage of intestinal epithelial cell differentiation in determining the hazards of ingested particles.
•Carbon nanotube agglomeration is a critical point for ecotoxicity assessment.•Biosurfactants from Bacillus subtilis (surfactin and fengycin) are highly efficient dispersing agents for carbon ...nanotubes.•A well characterized carbon nanotube sample was used in this study.•New methods for environmental nanotoxicology and bionanotechnology.
In this work, we evaluate the efficiency of biosurfactants produced by Bacillus subtilis LSFM-05 for the dispersion of acid-treated multi-walled carbon nanotubes (CNT-LQES1) and the effect of dispersion on toxicity testing with Daphnia similis. Carbon nanotubes are very hydrophobic materials and they readily agglomerate in mineral water. As a result, in order to determine their toxicity it is critical to evaluate methods to disperse these nanomaterials in a biologically compatible manner. The biosurfactant used in this work, termed BioS, which is a mixture of the lipopeptides (surfactin and fengycin), was found to be non-toxic to D. similis in an acute toxicity test (48h) and it was an excellent dispersing agent for CNT-LQES1 in reconstituted mineral water. Monitoring in real-time using the nanoparticle tracking analysis (NTA) showed that the colloidal stability of the CNT-LQES1 suspension dispersed with BioS was highly stable. These findings are encouraging for the application of biosurfactants as nontoxic dispersion agents in the emerging fields of bionanotechnology and nanotoxicology.
Context.
The ability to detect and characterise an increasing variety of exoplanets has been made possible by the continuous development of stable, high-resolution spectrographs and the Doppler ...radial velocity (RV) method. The cross-correlation function (CCF) method is one of the traditional approaches used to derive RVs. More recently, template matching has been introduced as an advantageous alternative for M-dwarf stars.
Aims.
We describe a new implementation of the template matching technique for stellar RV estimation within a semi-Bayesian framework, providing a more statistically principled characterisation of the RV measurements and associated uncertainties. This methodology, named the Semi-Bayesian Approach for RVs with Template matching, S-BART, can currently be applied to HARPS and ESPRESSO data. We first validate its performance with respect to other template matching pipelines using HARPS data. We then apply S-BART to ESPRESSO observations, comparing the scatter and uncertainty of the derived RV time series with those obtained using the CCF method. We leave a full analysis of the planetary and activity signals present in the considered datasets for future work.
Methods.
In the context of a semi-Bayesian framework, a common RV shift is assumed to describe the difference between each spectral order of a given stellar spectrum and a template built from the available observations. Posterior probability distributions are obtained for the relative RV associated with each spectrum using the Laplace approximation, after marginalization with respect to the continuum. We also implemented, for validation purposes, a traditional template matching approach, where a RV shift is estimated individually for each spectral order and the final RV estimate is calculated as a weighted average of the RVs of the individual orders.
Results.
The application of our template-based methods to HARPS archival observations of Barnard’s star allowed us to validate our implementation against other template matching methods. Although we find similar results, the standard deviation of the RVs derived with S-BART is smaller than that obtained with the HARPS-TERRA and SERVAL pipelines. We believe this is due to differences in the construction of the stellar template and the handling of telluric features. After validating S-BART, we applied it to 33 ESPRESSO GTO targets, evaluating its performance and comparing it to the CCF method as implemented in ESO’s official pipeline. We find a decrease in the median RV scatter of ~10 and ~4% for M- and K-type stars, respectively. Our semi-Bayesian framework yields more precise RV estimates than the CCF method, in particular in the case of M-type stars where S-BART achieves a median uncertainty of ~15 cm s
−1
over 309 observations of 16 targets. Further, with the same data we estimated the nightly zero point (NZP) of the instrument, finding a weighted NZP scatter of below ~0.7 m s
−1
. Given that this includes stellar variability, photon noise, and potential planetary signals, it should be taken as an upper limit on the RV precision attainable with ESPRESSO data.
A multi-variable smart sensor is presented able to gather, validate, and locally process data on both temperature and tri-axial vibration, as part of an instrumentation system which, integrating ...small, smart, and deeply embedded `field' devices in large numbers, may address the data requirements placed by new sophisticated Predictive Maintenance criteria applied to industrial rotating machinery.
Highlights • We investigated the benefits of visual cues on gait in Parkinson’s disease (PD). • Participants used visual information in both on-line and feedforward modes. • Both groups plan each ...step individually while walking on a cued pathway. • Exproprioception is not crucial for gait benefits achieved with visual cues in PD. • Visual cues facilitate a compensatory shift to goal-directed mode of gait control.
“Orangutan” is derived from the Malay term “man of the forest” and aptly describes the Southeast Asian great apes native to Sumatra and Borneo. The orangutan species,
Pongo abelii
(Sumatran) and
...Pongo pygmaeus
(Bornean), are the most phylogenetically distant great apes from humans, thereby providing an informative perspective on hominid evolution. Here we present a Sumatran orangutan draft genome assembly and short read sequence data from five Sumatran and five Bornean orangutan genomes. Our analyses reveal that, compared to other primates, the orangutan genome has many unique features. Structural evolution of the orangutan genome has proceeded much more slowly than other great apes, evidenced by fewer rearrangements, less segmental duplication, a lower rate of gene family turnover and surprisingly quiescent
Alu
repeats, which have played a major role in restructuring other primate genomes. We also describe the first primate polymorphic neocentromere, found in both
Pongo
species, emphasizing the gradual evolution of orangutan genome structure. Orangutans have extremely low energy usage for a eutherian mammal
1
, far lower than their hominid relatives. Adding their genome to the repertoire of sequenced primates illuminates new signals of positive selection in several pathways including glycolipid metabolism. From the population perspective, both
Pongo
species are deeply diverse; however, Sumatran individuals possess greater diversity than their Bornean counterparts, and more species-specific variation. Our estimate of Bornean/Sumatran speciation time, 400k years ago (ya), is more recent than most previous studies and underscores the complexity of the orangutan speciation process. Despite a smaller modern census population size, the Sumatran effective population size (
N
e
) expanded exponentially relative to the ancestral
N
e
after the split, while Bornean
N
e
declined over the same period. Overall, the resources and analyses presented here offer new opportunities in evolutionary genomics, insights into hominid biology, and an extensive database of variation for conservation efforts.
Statistical studies of exoplanets have shown that giant planets are more commonly hosted by metal-rich dwarf stars than low-metallicity ones, while such a correlation is not evident for lower-mass ...planets. The search for giant planets around metal-poor stars and the estimate of their occurrence \(f_p\) is an important element in providing support to models of planet formation. We present results from the HARPS-N search for giant planets orbiting metal-poor (\(-1.0\leqFe/H\leq-0.5\) dex) stars in the northern hemisphere complementing a previous HARPS survey on southern stars in order to update the estimate of \(f_p\). High-precision HARPS-N observations of 42 metal-poor stars are used to search for planetary signals to be fitted using differential evolution MCMC single-Keplerian models. We then join our detections to the results of the previous HARPS survey on 88 metal-poor stars to provide a preliminar estimate of the two-hemisphere \(f_p\). We report the detection of two new giant planets around HD 220197 and HD 233832. The first companion has M\(\sin{i}=0.20_{-0.04}^{+0.07}\) M\(_{\rm Jup}\) and orbital period of \(1728_{-80}^{+162}\) days, and for the second companion we find two solutions of equal statistical weight having periods \(2058_{-40}^{+47}\) and \(4047_{-117}^{+91}\) days and minimum masses of \(1.78_{-0.06}^{+0.08}\) and \(2.72_{-0.23}^{+0.23}\) M\(_{\rm Jup}\), respectively. Joining our two detections with the three from the southern survey we obtain a preliminary and conservative estimate of global frequency of \(f_p=3.84_{-1.06}^{+2.45}\%\) for giant planets around metal-poor stars. The two new giant planets orbit dwarf stars at the metal-rich end of the HARPS-N metal-poor sample, corroborating previous results suggesting that giant planet frequency still is a rising function of host star Fe/H. We also note that all detections in the overall sample are giant long-period planets.
• Enabling data reuse and knowledge discovery is increasingly critical in modern science, and requires an effort towards standardising data publication practices. This is particularly challenging in ...the plant phenotyping domain, due to its complexity and heterogeneity.
• We have produced the MIAPPE 1.1 release, which enhances the existing MIAPPE standard in coverage, to support perennial plants, in structure, through an explicit data model, and in clarity, through definitions and examples.
• We evaluated MIAPPE 1.1 by using it to express several heterogeneous phenotyping experiments in a range of different formats, to demonstrate its applicability and the interoperability between the various implementations. Furthermore, the extended coverage is demonstrated by the fact that one of the datasets could not have been described under MIAPPE 1.0.
• MIAPPE 1.1 marks a major step towards enabling plant phenotyping data reusability, thanks to its extended coverage, and especially the formalisation of its data model, which facilitates its implementation in different formats. Community feedback has been critical to this development, and will be a key part of ensuring adoption of the standard.
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