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Excess chromospheric emissions within deep photospheric lines are effective proxies of stellar magnetism for FGK stars. This emission decays with stellar age and is a potential determinant of this important stellar quantity. We report absolutely calibrated H  |$\alpha$| chromospheric fluxes for 511 solar-type stars in a wide interval of precisely determined masses, [Fe/H], ages, and evolution states from high S/N, moderately high |$-$| resolution spectra. The comparison of H  |$\alpha$| and H + K chromospheric fluxes reveals a metallicity bias (absent from H  |$\alpha$|⁠) affecting Ca  ii H + K fluxes thereby metal-rich stars with deep line profiles mimic low chromospheric flux levels, and vice versa for metal-poor stars. This bias blurs the age–activity relation, precluding age determinations for old, inactive stars unless mass and [Fe/H] are calibrated into the relation. The H + K lines being the most widely studied tool to quantify magnetic activity in FGK stars, care should be exercised in its use whenever wide ranges of mass and [Fe/H] are involved. The H  |$\alpha$| age–activity–mass–metallicity calibration appears to be in line with the theoretical expectation that (other parameters being equal) more massive stars possess narrower convective zones and are less active than less massive stars, while more metal-rich stars have deeper convective zones and appear more active than metal-poorer stars. If regarded statistically in tandem with other age diagnostics, H  |$\alpha$| chromospheric fluxes may be suitable to constrain ages for FGK stars with acceptable precision. [ABSTRACT FROM AUTHOR]

The advent of massive broad-band photometric surveys enabled photometric redshift estimates for unprecedented numbers of galaxies and quasars. These estimates can be improved using better algorithms or by obtaining complementary data such as narrow-band photometry, and broad-band photometry over an extended wavelength range. We investigate the impact of both approaches on photometric redshifts for quasars using data from Southern Photometric Local Universe Survey (S-PLUS) DR4, Galaxy Evolution Explorer (GALEX) DR6/7, and the unWISE catalog for the Wide-field Infrared Survey Explorer (WISE) in three machine learning methods: Random Forest, Flexible Conditional Density Estimation (FlexCoDE), and Bayesian Mixture Density Network (BMDN). Including narrow-band photometry improves the root-mean-square error by 11 per cent in comparison to a model trained with only broad-band photometry. Narrow-band information only provided an improvement of 3.8 per cent when GALEX and WISE colours were included. Thus, narrow bands play a more important role for objects that do not have GALEX or WISE counterparts, which respectively makes 92 per cent and 25 per cent of S-PLUS data considered here. Nevertheless, the inclusion of narrow-band information provided better estimates of the probability density functions obtained with FlexCoDE and BMDN. We publicly release a value-added catalogue of photometrically selected quasars with the photo- z predictions from all methods studied here. The catalogue provided with this work covers the S-PLUS DR4 area (∼3000 square degrees), containing 645 980, 244 912, 144 991 sources with the probability of being a quasar higher than, 80 per cent, 90 per cent, 95 per cent up to r < 21.3 and good photometry quality in the detection image. More quasar candidates can be retrieved from the S-PLUS data base by considering less restrictive selection criteria. [ABSTRACT FROM AUTHOR]

All-sky multiband photometric surveys represent a unique opportunity of exploring rich nearby galaxy clusters up to several virial radii, reaching the filament regions where pre-processing is expected to occur. These projects aim to tackle a large number of astrophysical topics, encompassing both the Galactic and extragalactic fields. In that sense, generating large catalogues with homogeneous photometry for both resolved and unresolved sources that might be interesting to achieve specific goals, imposes a compromise when choosing the set of parameters to automatically detect and measure such a plethora of objects. In this work, we present the acquired experience on studying the galaxy content of the Fornax cluster using large catalogues obtained by the Southern Photometric Local Universe Survey (S-PLUS). We realized that some Fornax bright galaxies are missed in the S-PLUS iDR4 catalogues. In addition, Fornax star-forming galaxies are included as multiple detections due to overdeblending. To solve those issues, we performed specific SExtractor runs to identify the proper set of parameters to recover as many Fornax galaxies as possible with confident photometry and avoiding duplications. From that process, we obtained new catalogues containing 12-band improved photometry for ∼ 3 × 106 resolved and unresolved sources in an area of ∼ 208 deg2 in the direction of the Fornax cluster. Together with identifying the main difficulties to carry out the study of nearby groups and clusters of galaxies using S-PLUS catalogues, we also share possible solutions to face issues that seem to be common to other ongoing photometric surveys. [ABSTRACT FROM AUTHOR]

Cork composites have shown excellent potential in impact mitigating systems. Their sustainability greatly surpasses the currently used solutions. In addition, recent advances in developing cork composites with shear thickening fluids (STFs) have demonstrated exciting results for impact mitigation. This study explores different STF formulations based on polyethylene glycol (PEG), with a molecular weight of 400 g/mol, and SiO2 particles, investigating their application in layered cork composites for impact mitigation. Different STF formulations are investigated by processing suspensions with different fumed silica concentrations ranging from 10 to 60 wt.%. Using a cone–plate configuration, rheological measurements were conducted on these suspensions, which were then employed as an interfacial layer in agglomerated cork composite layered structures. These hybrid composites were then subjected to 20 J impact tests. PEG 400 exhibited fluid final states for silica concentrations up to 30 wt.% and crystallised at higher concentrations. Based on the results, STF within cork layers was positive regarding impact force reduction, drawing insights for future application of STF suspensions in cork composites for impact mitigation. [ABSTRACT FROM AUTHOR]

The morphological diversity of galaxies is a relevant probe of galaxy evolution and cosmological structure formation. However, in large sky surveys, even the morphological classification of galaxies into two classes, like late-type (LT) and early-type (ET), still represents a significant challenge. In this work, we present a Deep Learning (DL) based morphological catalogue built from images obtained by the Southern Photometric Local Universe Survey (S-PLUS) Data Release 3 (DR3). Our DL method achieves a purity rate of 98.5 per cent in accurately distinguishing between spiral, as part of the larger category of LT galaxies, and elliptical, belonging to ET galaxies. Additionally, we have implemented a secondary classifier that evaluates the quality of each galaxy stamp, which allows to select only high-quality images when studying properties of galaxies on the basis of their DL morphology. From our LT/ET catalogue of galaxies, we recover the expected colour–magnitude diagram in which LT galaxies display bluer colours than ET ones. Furthermore, we also investigate the clustering of galaxies based on their morphology, along with their relationship to the surrounding environment. As a result, we deliver a full morphological catalogue with 164 314 objects complete up to r petro < 18, covering ∼1800 deg2, from which ∼55 000 are classified as high reliability, including a significant area of the Southern hemisphere that was not covered by previous morphology catalogues. [ABSTRACT FROM AUTHOR]

The Magellanic Clouds are the most massive and closest satellite galaxies of the Milky Way (MW), with stars covering ages from a few Myr up to 13 Gyr. This makes them important for validating integrated light methods to study stellar populations and star formation processes, which can be applied to more distant galaxies. We characterized a set of stellar clusters in the Small Magellanic Cloud (SMC), using the Southern Photometric Local Universe Survey. This is the first age (metallicity) determination for 11 (65) clusters of this sample. Through its seven narrow bands, centred on important spectral features, and five broad bands, we can retrieve detailed information about stellar populations. We obtained ages and metallicities for all stellar clusters using the Bayesian spectral energy distribution fitting code bagpipes. With a sample of clusters in the colour range −0.20 < r − z < +0.35, for which our determined parameters are most reliable, we modeled the age–metallicity relation of SMC. At any given age, the metallicities of SMC clusters are lower than those of both the Gaia Sausage-Enceladus disrupted dwarf galaxy and the MW. In comparison with literature values, differences are Δlog(age) ≈ 0.31 and Δ[Fe/H] ≈ 0.41, which is comparable to low-resolution spectroscopy of individual stars. Finally, we confirm a previously known gradient, with younger clusters in the centre and older ones preferentially located in the outermost regions. On the other hand, we found no evidence of a significant metallicity gradient. [ABSTRACT FROM AUTHOR]

Metal-poor stars are key to our understanding of the early stages of chemical evolution in the Universe. New multifilter surveys, such as the Southern Photometric Local Universe Survey (S-PLUS), are greatly advancing our ability to select low-metallicity stars. In this work, we analyse the chemodynamical properties and ages of 522 metal-poor candidates selected from the S-PLUS data release 3. About 92 per cent of these stars were confirmed to be metal-poor ([Fe/H] ≤ −1) based on previous medium-resolution spectroscopy. We calculated the dynamical properties of a subsample containing 241 stars, using the astrometry from Gaia Data Release 3. Stellar ages are estimated by a Bayesian isochronal method formalized in this work. We analyse the metallicity distribution of these metal-poor candidates separated into different subgroups of total velocity, dynamical properties, and ages. Our results are used to propose further restrictions to optimize the selection of metal-poor candidates in S-PLUS. The proposed astrometric selection (parallax >0.85 mas) is the one that returns the highest fraction of extremely metal-poor stars (16.3 per cent have [Fe/H] ≤ −3); the combined selection provides the highest fraction of very metal-poor stars (91.0 per cent have [Fe/H] ≤ −2), whereas the dynamical selection (eccentricity >0.35 and discness < 0.75) is better for targeting metal-poor (99.5 per cent have [Fe/H] ≤ −1). Using only S-PLUS photometric selections, it is possible to achieve selection fractions of 15.6, 88.5, and 98.3 per cent for metallicities below −3, −2, and −1, respectively. We also show that it is possible to use S-PLUS to target metal-poor stars in halo substructures such as Gaia -Sausage/Enceladus, Sequoia, Thamnos, and the Helmi stream. [ABSTRACT FROM AUTHOR]

The Southern Photometric Local Universe Survey (S-PLUS) is an ongoing survey of ∼9300 deg2 in the southern sky in a 12-band photometric system. This paper presents the second data release (DR2) of S-PLUS, consisting of 514 tiles covering an area of 950 deg2. The data has been fully calibrated using a new photometric calibration technique suitable for the new generation of wide-field multifilter surveys. This technique consists of a χ2 minimization to fit synthetic stellar templates to already calibrated data from other surveys, eliminating the need for standard stars and reducing the survey duration by ∼15 per cent. We compare the template-predicted and S-PLUS instrumental magnitudes to derive the photometric zero-points (ZPs). We show that these ZPs can be further refined by fitting the stellar templates to the 12 S-PLUS magnitudes, which better constrain the models by adding the narrow-band information. We use the STRIPE82 region to estimate ZP errors, which are ≲ 10 mmags for filters J0410, J0430, g , J0515, r , J0660, i , J0861 and z ; ≲ 15 mmags for filter J0378; and ≲ 25 mmags for filters u and J0395. We describe the complete data flow of the S-PLUS/DR2 from observations to the final catalogues and present a brief characterization of the data. We show that, for a minimum signal-to-noise threshold of 5, the photometric depths of the DR2 range from 19.1 to 20.5 mag (measured in Petrosian apertures), depending on the filter. The S-PLUS DR2 can be accessed from the website: https://splus.cloud. [ABSTRACT FROM AUTHOR]

This paper provides a catalogue of stars, quasars, and galaxies for the Southern Photometric Local Universe Survey Data Release 2 (S-PLUS DR2) in the Stripe 82 region. We show that a 12-band filter system (5 Sloan-like and 7 narrow bands) allows better performance for object classification than the usual analysis based solely on broad bands (regardless of infrared information). Moreover, we show that our classification is robust against missing values. Using spectroscopically confirmed sources retrieved from the Sloan Digital Sky Survey DR16 and DR14Q, we train a random forest classifier with the 12 S-PLUS magnitudes + 4 morphological features. A second random forest classifier is trained with the addition of the W1 (3.4  |$\mu\mathrm{m} $|⁠) and W2 (4.6  |$\mu\mathrm{m} $|⁠) magnitudes from the Wide-field Infrared Survey Explorer (WISE). Forty-four per cent of our catalogue have WISE counterparts and are provided with classification from both models. We achieve 95.76 per cent (52.47 per cent) of quasar purity, 95.88 per cent (92.24 per cent) of quasar completeness, 99.44 per cent (98.17 per cent) of star purity, 98.22 per cent (78.56 per cent) of star completeness, 98.04 per cent (81.39 per cent) of galaxy purity, and 98.8 per cent (85.37 per cent) of galaxy completeness for the first (second) classifier, for which the metrics were calculated on objects with (without) WISE counterpart. A total of 2926 787 objects that are not in our spectroscopic sample were labelled, obtaining 335 956 quasars, 1347 340 stars, and 1243 391 galaxies. From those, 7.4 per cent, 76.0 per cent, and 58.4 per cent were classified with probabilities above 80 per cent. The catalogue with classification and probabilities for Stripe 82 S-PLUS DR2 is available for download. [ABSTRACT FROM AUTHOR]

We propose a new way to assess the output signal of a quantum-well infrared photodetector (QWIP). Instead of measuring the photocurrent produced by the device, as usually done, we show that the noise induced by the absorption process can be used to generate a useful detection signal. We built a simple electronic circuit able to quantify the noise of an AlGaAs/GaAs QWIP that was intentionally designed to produce no photocurrent at all, and we demonstrated that such a circuit was able to generate a strong output signal whenever an infrared radiation of a specific wavelength was shed on the detector. This concept opens new possibilities for the design of novel types of photodetection systems. [ABSTRACT FROM AUTHOR]

Aim: To compare six reciprocating instruments regarding their geometric design, metallurgical characteristics, mechanical behaviour and ability to prepare root canals. Methodology: A total of 246 new 25‐mm NiTi instruments (41 per group) from six reciprocating systems (Reciproc, Reciproc Blue, One Files, One Files Blue, Reverso Silver, and WaveOne Gold) were evaluated throughout a multimethod approach regarding their design using stereomicroscopy (number of blades and helix angle) and scanning electron microscopy (blades symmetry, cross section and surface finishing), nickel‐titanium composition, phase transformation temperatures, mechanical performance (cyclic fatigue, torsional and bending resistance) and unprepared canal surface area on anatomically matched mandibular molars assessed by micro‐CT. One‐way ANOVA and post hoc Tukey's or Mood's median tests were selected depending on sample distribution with significance level set at 5%. Results: The instruments had similarities regarding their metal composition and unprepared canal area, whilst differences in phase transformation temperatures and geometric design (number of blades, surface finishing and tip geometry) were observed. Overall, no difference was observed regarding the maximum torque values (P > 0.05), whilst One Files (72 s) and One Files Blue (414 s) had the shortest and longest times to fracture, respectively (P < 0.05). Similar angles of rotation were observed in Reciproc (310°), One Files (285°) and Reverso Silver (318°) instruments (P > 0.05), which were significantly lower than Reciproc Blue (492°), One Files Blue (456°) and WaveOne Gold (492°; P < 0.05). Maximum bending load demonstrated that Reciproc Blue (201.3 gf) was significantly more flexible that the other instruments (P < 0.05). Conclusion: Although there were similarities in metal composition and percentage of unprepared canal surface, the instruments had differences in the overall geometric design, phase transformation temperatures and in the four mechanical resistance parameters (time to fracture, maximum torque, angle of rotation and maximum bending load). [ABSTRACT FROM AUTHOR]

Accident reconstructions and numerical simulations are used to evaluate and improve protective systems. Virtual testing and numerical methods can assist in the improvement safety of vulnerable road users. This work presents the tremendous potential of using computer-aided engineering by describing the development of a windshield numerical model and its damage and fracture validation. The motivation behind this study is the possibility of using such a model in the reconstruction of road accidents involving vulnerable road users. The main goal is the development and validation of a finite element model of an automobile windshield in order to use it in further studies regarding the reconstruction of road traffic accidents. In order to validate it according to experimental studies available in the literature, the 4.8 kg standard adult headform from the European Enhanced Vehicle Safety Committee is also developed and validated. A total of eight impacts at six different locations and carried at two different impact velocities (6 m/s and 11.1 m/s) were simulated. The validation of the windshield model, and consequently the damage model employed to simulate glass cracking initiation and propagation, were accomplished by comparing the acceleration at the headform's centre of gravity and the windshield's fracture pattern against experimental data. [ABSTRACT FROM AUTHOR]

The development of Pickering emulsions as ecologically correct stabilized with bio-based material by substituting synthetic petroleum-derived tensoactives assumed a very attractive level, representing the current guideline of the global market for homecare industry, food and beverage applications. In this wor, cellulose nanocrystals (CNCs), a hierarchically advanced biomaterial, were produced to stabilize innovative emulsions formulated with western soapberry Sapindus saponaria L. oil (SO). Besides, green surfactants (triterpene saponins extracted from S. saponaria L. pericarp; SAP) were also investigated to stabilize the oil/water interface. The synergistic combination between cellulose nanowhiskers and the bioactive glycosides has never been reported in the literature. Dynamic interfacial tensions of SAP and SO were firstly investigated, and their capacity to form a plastic membrane at oil/water interface was revealed. Response surface methodology (RSM) was employed to study the influence of the binary systems (CNC:SAP) on the stability of emulsified systems, such as size and zeta potential. In addition, a new calculation was proposed to determine the coverage of the oil droplets formed by the mixture of cellulose crystallites and natural surfactants. The optimal nanoemulsion composition was determined to be 60 w/w (%) of water, 23.905 w/w % of SO, 5 w/w % of CNC and 8.095 w/w% of SAP to produce of smallest droplet (165.1 nm) combined with higher zeta potential module (−46.7 mV). Results highlight the potential of Sapindus saponins and cellulose nanowhiskers for efficient producing label-friendly nanoemulsions applicable for drug, cosmeceutical or edible delivery systems. [ABSTRACT FROM AUTHOR]

In this paper, the influence of TiSiN layer thickness of TiSiN/VN multilayered films, deposited by DC reactive magnetron sputtering, on the structure, mechanical properties, thermal stability and, essentially, oxidation resistance is investigated. The films adhere well to the substrates and show a columnar structure growth, being the one with the highest TiSiN layer thickness the more compact. The as-deposited films exhibit fcc structure with broad diffraction peaks positioned between the TiN and VN standard peaks. Annealing at 800 °C for 2 h promotes structural changes in the films, i.e., single fcc diffraction peaks are subdivided into two diffraction contributions. The onset point of oxidation of the films is ~ 550 °C, independently of the thickness of the TiSiN layer. A strong diffusion of V to the top surface occurs for the film with the lowest TiSiN layer thickness. Thicker TiSiN layers offer a better barrier layer to the V diffusion due to the formation of a higher amount of protective oxides. The strong diffusion of V produces a plate-like V2O5 discontinuous layer on the top and a porous Ti-Si-V-O rich thick layer underneath. [ABSTRACT FROM AUTHOR]

Aim: To compare the ProTaper Next (PTN) system with a replica‐like and a counterfeit system regarding design, metallurgy, mechanical performance and shaping ability. Methodology: Replica‐like (X‐File) and counterfeit (PTN‐CF) instruments were compared to the PTN system regarding design (microscopy), phase transformation temperatures (differential scanning calorimetry), nickel‐titanium ratio (energy‐dispersive X‐ray spectroscopy), cyclic fatigue, torsional resistance, bending strength, and untouched canal areas in extracted mandibular molars (micro‐CT). anova,post hoc Tukey's and Kruskal–Wallis tests were used according to normality assessment (Shapiro–Wilk test) with the significance level set at 5%. Results: Overall similarities in design and nickel‐titanium (Ni/Ti) ratio were observed amongst instruments with the X‐File having a smoother surface finish. PTN and PTN‐CF had mixed austenite plus R‐phase (R‐phase start approximately at 45 ºC and near 30 ºC, respectively), whilst X‐File instruments were austenitic (R‐phase started at approximately at 17 ºC) at room temperature (20 ºC). PTN‐CF had the greatest inconsistency in the phase transformation temperatures. Time to fracture of PTN‐CF X2 and X3 was significantly shorter than PTN and X‐File instruments (P < 0.05), whilst no difference was noted in maximum torque to fracture amongst the tested systems (P > 0.05). X‐Files and PTN‐CF had a stress‐induced phase change during bending load. Mean unprepared surface areas of root canals were 25.8% (PTN), 31.1% (X‐File) and 32.5% (PTN‐CF) with no significant difference amongst groups (P > 0.05). Conclusion: Similarities amongst the systems were noted in the Ni/Ti ratio and maximum torque to fracture, whilst differences were observed in the design, phase transformation temperatures and mechanical behaviour. The ProTaper Next counterfeit instruments could be considered as the less secure system considering its low‐cyclic fatigue resistance. Apart from these differences, the unprepared canal surface areas, obtained with the tested systems, were similar. [ABSTRACT FROM AUTHOR]

The close relationship between the nature of the Triangulum–Andromeda (TriAnd) overdensity and the Galactic disk has become increasingly evident in recent years. However, the chemical pattern of this overdensity (RGC = 20–30 kpc) is unique and differs from what we know of the local disk. In this study, we analyze the chemical abundances of five α elements (Mg, O, Si, Ca, and Ti) in a sample of stars belonging to the TriAnd overdensity, including stars with [Fe/H] < −1.2, to investigate the evolution of the α elements with metallicity. High-resolution spectra from Gemini North with GRACES were analyzed. Overall, the TriAnd population presents an α-element pattern that differs from that of the local disk; the TriAnd stars fall in between the local disk and the dwarf galaxies in the [X/Fe] versus [Fe/H] plane. The high [Mg/Fe] ratios obtained for the lower metallicity TriAnd stars may indicate a roughly parallel sequence to the Milky Way local disk at lower values of [Fe/H], revealing a knee shifted toward lower metallicities for the TriAnd population. Similar behavior is also exhibited in the [Ca/Fe] and [Si/Fe] ratios. However, for O and Ti the behavior of the [X/Fe] ratios shows a slight decay with decreasing metallicity. Our results reinforce the TriAnd overdensity as a unique stellar population of the Milky Way, with an abundance pattern that is different from all stellar populations studied to date. The complete understanding of the complex TriAnd population will require high-resolution spectroscopic observations of a larger sample of TriAnd stars. [ABSTRACT FROM AUTHOR]

This article focused on the microstructure characterization and residual stress measurements of the flange from classes D and C railway wheels (called 7D and 7C steel, respectively) to contribute with the residual stress level on new forged wheels flange area. A correlation with the hardness was conducted. The residual stress was measured in three points of the flange using the x-ray diffraction technique, and the microstructure characterization on SEM microscopy. We found the 7C steel has fine pearlite and ferrite microstructures, and 7D steel has degenerated pearlite and bainite microstructures. In the 7D steel, the compressive residual stress in the flange region was higher than in the 7C steel, which is related to the presence of bainite on the microstructure. There was a correlation between the hardness and residual stress value. The knowledge of the residual compression stress level is important for safety train wheels operation. The traction stress generated by the brake system on the wheel is attenuated by residual compression stress. [ABSTRACT FROM AUTHOR]

The change of wine grape harvest from wet season (summer) to dry season (winter) by changing the pruning management has improved quality of wines produced in the Brazilian Southeast. However, the vines need to be spur pruned twice a year, i.e. with a 1st pruning in August (winter pruning) for a vegetative cycle during the hot and wet summer, and a 2nd pruning in January (summer pruning) for a productive cycle during the cold and dry season. This double pruning strategy is made necessary by the fact that latent buds developed during the dry season cycle are not fruitful to support a productive cycle in the following year. This histological study, performed in the South of Minas Gerais State (Brazil), showed that annual single pruning done in the wet season (in January) displayed a high rate of necrosis on primary and secondary buds (bud necrosis - BN). In April, 99 days after summer pruning (DASP), the rates of BN were 40% and 50% at basal and apical node positions, respectively, reaching 80% of BN in December (322 DASP). As a consequence of BN, bud potential fertility was drastically reduced from 0.5 inflorescence primordial (IP) per bud (in July) to 0.06 (in December) and bud burst in the next cycle from secondary and tertiary bud axes. Vines managed by double pruning system (submitted to summer and winter pruning) displayed a much higher fruitfulness potential, i.e. 1.46 IP per bud in December (112 days after winter pruning) and limited BN occurrence (20%). On single pruned vines, we also observed a significant decrease of starch content in canes, trunks and roots. Internal bud anatomy showed that a random cell breakdown started 70 days DASP. At 211 DASP, all buds showed a large starch granule concentration, raphides and crystals of calcium oxalate inside idioblasts of leaf primordia and also in cortical parenchyma of the vegetative axis. The bud starch content was increased and a positive correlation between necrosis and starch accumulation was observed. The impact of carbohydrate availability on bud necrosis development was discussed. This study showed that the necrosis development towards secondary and tertiary axis of the dry season buds is the main reason of unfruitfulness in the vineyards managed by single pruning in the wet season, making the double pruning compulsory. [ABSTRACT FROM AUTHOR]

Sheep production systems in Brazilian caatinga rangelands require supplementation adapted to changes in floristic and chemical composition as dry seasons progress. Meeting sheep nutritional needs in extensive semiarid systems is challenging because of sheep dietary preferences and habits. The objective of this trial was to evaluate the substitutive effect of concentrate supplementation on grazing sheep in the Brazilian caatinga rangeland and its consequences on performance in different seasons. The trial was conducted from March to August 2013 at Embrapa Goat and Sheep in Sobral, Ceará State, Brazil. Thirty-two Brazilian Somali multiparous ewes were submitted to estrus synchronization and controlled breeding. At the start of the trial, ewes averaged 30.45 + 2.60 kg body weight (BW). Ewes were divided into four groups and individually offered 0, 200, 350, or 500 g supplement head−1 day−1. Intake prediction and digestibility trials were evaluated at three periods: rainy season (April), transition rainy-dry (June), and dry season (August). Sheep weights were taken every 14 days to measure their performance from late gestation until weaning. Ewe BW and body condition score changes were determined too. Lamb BW changes were also measured every 14 days from birth through weaning. A completely randomized design with split plot arrangement using eight replications was used for intake and digestibility measurements. The differences between supplement offered (0, 200, 350, and 500 g sheep-1) and season (rainy, transition rainy-dry, and dry) were submitted to analyses of variance and multiple means were separated, where differences were detected, using the Tukey's test. During lactation up through weaning, ewes supplemented at 500 g day−1 had greater BW than ewes without supplement. Ewes supplemented with 200 g concentrate head−1 day−1 had 9.1% greater (P ≤ 0.05) BW at weaning and their lambs had 19.7% greater birth and 16.6% heavier wean BW despite lower dry matter intake compared to unsupplemented animals. Supplementation with 200 g concentrate increased carrying capacity by 28.8% during the dry season and by 20.5% during the rainy season. This study confirmed that in the dry season, when quality of rangeland forages decreases, supplementation contributes to greater DMI, improves postpartum and lactation BW recovery of ewes, and contributes to greater lamb birth and wean weights. Moreover, supplementation leads to feed substitution effects that may increase rangeland resilience by mitigating overgrazing. Supplementation with 200 g concentrate can also prevent negative energy balance for grazing animals, improving longer postnatal recovery, longer intervals between parturitions, fewer double and is necessary to ensure a better BW at birth to lambs. [ABSTRACT FROM AUTHOR]

1I/'Oumuamua is the first interstellar object observed passing through the Solar System. Understanding the nature of these objects will provide crucial information about the formation and evolution of planetary systems, and the chemodynamical evolution of the Galaxy as a whole. We obtained the galactic orbital parameters of this object, considering eight different models for the Galaxy, and compared it to those of stars of different ages from the Geneva-Copenhagen Survey (GCS). Assuming that the galactic orbital evolution of this object is similar to that of stars, we applied a Bayesian analysis and used the distribution of stellar velocities, as a function of age, to obtain a probability density function for the age of 'Oumuamua. We considered two models for the age–velocity dispersion relation (AVR): the traditional power law, fitted using data from the GCS, and a model that implements a second power law for younger ages, which we fitted using a sample of 153 open clusters (OCs). We find that the slope of the AVR is smaller for OCs than it is for field stars. Using these AVRs, we constrained an age range of 0.01–1.87 Gyr for 'Oumuamua and characterized a most likely age ranging between 0.20 and 0.45Gyr, depending on the model used for the AVR. We also estimated the intrinsic uncertainties of the method due to not knowing the exact value of the solar motion and the particularities of 1I/'Oumuamua's ejection. [ABSTRACT FROM AUTHOR]

A local harmonic (LH) propagator has been derived through an adequate splitting of the Hamiltonian operator. This propagator has been applied to study several quantum systems including a quartic oscillator, a double well potential, and the Morse potential. We have calculated equilibrium and dynamical properties using the transfer matrix path integral method. It has been verified that the LH propagator is significantly more accurate than other propagators proposed by several studies. For the LH propagator, higher order corrections to the Trotter formula lead to an excellent short time approximation. It is suggested that the LH propagator can be of wide interest for path integral studies of quantum systems. [ABSTRACT FROM AUTHOR]

We present a method to build a probability density function (PDF) for the age of a star based on its peculiar velocities U, V, and W and its orbital eccentricity. The sample used in this work comes from the Geneva-Copenhagen Survey (GCS) that contains the spatial velocities, orbital eccentricities, and isochronal ages for about 14 000 stars. Using the GCS stars, we fitted the parameters that describe the relations between the distributions of kinematical properties and age. This parametrization allows us to obtain an age probability from the kinematical data. From this age PDF, we estimate an individual average age for the star using the most likely age and the expected age. We have obtained the stellar age PDF for the age of 9102 stars from the GCS and have shown that the distribution of individual ages derived from our method is in good agreement with the distribution of isochronal ages. We also observe a decline in the mean metallicity with our ages for stars younger than 7 Gyr, similar to the one observed for isochronal ages. This method can be useful for the estimation of rough stellar ages for those stars that fall in areas of the Hertzsprung-Russell diagram where isochrones are tightly crowded. As an example of this method, we estimate the age of Trappist-1, which is a M8V star, obtaining the age of t(UVW) = 12.50(+0.29 - 6.23) Gyr. [ABSTRACT FROM AUTHOR]

Large geometry secondary ion mass spectrometry can be efficiently used to analyze uranium aerosol particles from dust samples in the search for undeclared nuclear activities. Automated sample screening measurements are followed by more precise and accurate microbeam measurements of both the major and minor uranium isotopes on selected individual particles. The quality of this work is essential in order to be able to draw valuable safeguards conclusions. This paper describes the latest developments that have been undertaken to enhance the detection limits and to reduce the uranium isotope measurement uncertainty. It includes improvements in the analytical protocol as well as in the instrument acquisition software and data reduction method. Recent useful yield measurements have been performed on uranium monodispersed particles using different primary bombardment conditions to compare to previously obtained data. Comparison of uranium isotope measurements when using pyrolytic graphite or silica planchets as a sample substrate will also be presented. [ABSTRACT FROM AUTHOR]

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Abstract: Aim: To evaluate the intratubular antimicrobial activity of several oxidant and chelating agents associated with or without surfactants in experimentally infected root canals, using confocal laser scanning microscopy. Methodology: Twenty‐four dentine blocks from bovine incisors were contaminated for 5 days with Enterococcus faecalis (ATCC‐ 29212). Ten contaminated dentine specimens were irrigated for 5 min with 5.25% NaOCl followed by 17% EDTA for 2 min, and the other 10 with Hypoclean for 5 min followed by Tetraclean NA for 2 min. The remaining four specimens were used as positive and negative controls (two samples each). Then, dentine blocks were stained with Live/Dead BacLight for analysis of the remaining live or dead bacteria using confocal laser scanning microscopy. Comparison between and within groups was performed using the Mann–Whitney test for independent samples and the Wilcoxon signed‐rank test, respectively. Results: After exposure to irrigants, the positive control group had a median of 67.41% of viable bacteria (95% CI: 48.15, 78.9), whilst the NaOCl+EDTA group and Hypoclean+Tetraclean NA group had 3.77% (1.28, 15.92) and 0.87% (−0.42, 4.30) of viable bacteria, respectively. These results were significantly different from each other, both overall and distinct by region (cervical and medium third), or depth (superficial and deep layer) (P < 0.01 in all cases). Conclusions: The use of adjunctive agents reducing the surface tension associated with oxidant and chelating agents improved the antimicrobial activity of irrigating solutions and intratubular decontamination against Enterococcus faecalis, possibly due to better removal of the smear layer and deeper penetration into dentinal tubules. [ABSTRACT FROM AUTHOR]

The development of forage cultivars suitable for the Brazilian Cerrados should incorporate long-term cattle performance results, ensuring released material be persistent and of high quality. The objective of the study was to evaluate the effect of three guineagrass [Megathyrsus maximus (Jacq.) B. K. Simon & S. W. L. Jacobs] cultivars (Massai, Tamani, and Zuri) on liveweight gain of young Nellore (Bos indicus) bulls under grazing. The trial was performed in Planaltina (Federal District, Brazil) from 2011 to 2013 encompassing dry and rainy seasons. Cattle average daily gain (ADG) in the rainy season differed among cultivars, averaging 0.716, 0.791, and 0.883 kg head-1 d-1 for Massai, Tamani, and Zuri, respectively. The ADG was lesser (0.284 kg head-1 d-1) in the dry season with no effects of cultivar. Massai had a similar stocking rate (SR) as Tamani but a greater SR than Zuri in the rainy season (490, 445, and 417 animal unit day ha-1), which was influenced by its greater herbage accumulation rate (HAR; 66.8, 41.4 and 42.3 kg DM ha-1 d-1, respectively). However, there were no differences among cultivars in liveweight (LW) gain per area (GA 2.28 kg ha-1 d-1). In vitro dry matter digestibility (IVDMD) was lesser for Massai (530 g kg-1) compared to Tamani and Zuri (561 and 550 g kg-1, respectively). Due to above-average nutritive value, Tamani and Zuri provided greater individual cattle performance than Massai, although the GA was similar among all cultivars. [ABSTRACT FROM AUTHOR]

Background: Platelet transfusion therapy poses many challenges in veterinary clinical practice. Lack of readily available blood donors, short shelf-life, and inability to administer a sufficient number of platelets to meet a dog's transfusion need are the major difficulties encountered. Platelet additive solutions are already in use at American and European human blood banks, showing to be a realistic alternative. This study compares the in vitro platelet function in plasma, Composol, or SSP+ during storage for 13 days. Platelet rich plasma-platelet concentrate with 35% plasma and 65% platelet additive solutions (Composol or SSP+) and a control group (100% plasma) were prepared. Swirling, platelet count, blood gases, metabolic variables, platelet activation markers, and apoptosis markers were analyzed on days 1, 5, 9 and 13. Results: Swirling was well preserved and pH was acceptable (> 6.2) during storage for all platelet additive solutions units until day 9. SSP + units showed more stable pH and metabolic variables until day 13. Platelets in plasma showed higher glucose consumption than in Composol or in SSP+. The platelet additive solutions units showed better platelet metabolism maintenance, reduced glucose consumption and lactate production. The apoptotic markers were still low for 9 days in platelet concentrates with platelet additive solutions, suggesting the possibility to extend the shelf life with the use of SSP+ or Composol. Conclusions: Our findings suggest that the uses of Composol and SSP+ in canine platelet concentrates are potential alternatives in veterinary blood banks. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (RGO) and titanium dioxide (TiO) nanoparticles were immobilized on cotton textile substrates to produce self-cleaning textiles. Varying number of layers of RGO and TiO nanoparticles were coated by a facile method, and their photocatalytic potential was evaluated by measuring the degradation rate of rhodamine B (Rh-B) in an aqueous solution in a photoreactor under simulated solar irradiation. X-ray diffraction (XRD) and zeta potential measurements of starting materials were studied as they are crucial for innovative methods of functionalization. The study confirms that it is possible to ensure a good adhesion of nanoparticles on textile samples without the use of a resin. The application of varying number of RGO and TiO coatings has influence on photocatalytic properties of functionalized cotton textile substrates. The energy band gap of the samples reduces from 3.25 to −3.20 eV with the number of RGO coatings. All five de-ethylated intermediates of Rh-B during the photocatalytic degradation were identified using a high-performance liquid chromatography-mass spectrometry method. The experimental results show that, in general, the higher the number of RGO coatings is, the higher the photocatalytic efficiency (η) of the functionalized substrate is (η=87% for three RGO coatings on TiO). [ABSTRACT FROM AUTHOR]

It is shown that the inclusion of dopant segregation, negative differential mobility and thermal assisted tunnelling to the calculation of dark current activation energy provides a much better fitting to the experimental results than geometrical or Poole-Frenkel models and handles well its voltage asymmetry and nonlinearity. Besides, the transport model obtained is able to fit the current-voltage curves for both bias polarities with almost the same transport parameters. A practical method to estimate the segregation length is discussed. A consequence of this method is a more accurate set of values for the transport parameters of the structure, considering direct and reverse bias. [ABSTRACT FROM AUTHOR]

Background: Excessive air pollution in urban environments can impact morbidity and mortality. The authors evaluated the role of particulate matter2.5 (PM2.5) in structural, geometric, and functional remodeling in hearts, using an experimental model of myocardial infarction. Methods and findings: Seventy-five rats were divided into 5 groups: control (CG), CG exposed to PM2.5 pollution (CGP), myocardial infarcted group (MI), infarcted group immediately exposed to pollution (IGP-I), and infarcted group previously exposed to pollution and kept exposed after infarction (IGP-II). Greater deposition of interstitial collagen occurred in the left ventricle in CGP, MI, IGP-I, and IGP-II groups compared with that in controls (p = 0.002 CG vs CGP and p<0.0001 CG vs MI, IGP-I, and IGP-II). In the right ventricle, greater collagen deposition existed in CGP, MI, IGP-I, and IGP-II compared with that in CG (p<0.021 CG vs CGP and p<0.0001 CG vs MI, IGP-I, and IGP-II). At the end of the study, CG had a higher mean shortening fraction than the other groups had (p≤0.03). Left ventricular systolic diameter was lower in CG than in infarcted groups (p≤0.003). The infarcted groups had greater expression of TGF-β (p≤0.04). PM2.5 increased the expression of TGF-β in the IGP-II compared with the MI group (p = 0.004). The TNF-α gene was overexpressed in the IGP-II compared with the CGP group (p = 0.012). INF-γ gene expression was greater in IGP-II (p≤0.01). Oxidative stress analysis showed a higher glutathione concentration in CGP (p = 0.03), MI (p = 0.014), and IGP-I (p = 0.008) compared with that in CG. Conclusions: PM2.5 stimulates the deposition of fibrosis in the myocardium of healthy hearts, but not in infarcted hearts. PM2.5 modulates the inflammatory response, which was greater in the IGP-II group. It also modulates oxidative stress in healthy hearts but not in infarcted hearts. [ABSTRACT FROM AUTHOR]

Copyright of HOLOS is the property of Instituto Federal do Rio Grande do norte - IFRN and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of HOLOS is the property of Instituto Federal do Rio Grande do norte - IFRN and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and Aims: Recent studies have proposed that if a severe caloric restriction (SCR) is initiated at the earliest period of postnatal life, it can lead to beneficial cardiac adaptations later on. We investigated the effects of SCR in Wistar rats from birth to adult age on risk factors for cardiac diseases (CD), as well as cardiac function, redox status, and HSP72 content in response to ischemia/reperfusion (I/R) injury. Methods and Results: From birth to the age of 3 months, CR50 rats were fed 50% of the food that the ad libitum group (AL) was fed. Food intake was assessed daily and body weight were assessed weekly. In the last week of the SCR protocol, systolic blood pressure and heart rate were measured and the double product index was calculated. Also, oral glucose and intraperitoneal insulin tolerance tests were performed. Thereafter, rats were decapitated, visceral fat was weighed, and blood and hearts were harvested for biochemical, functional, tissue redox status, and western blot analyzes. Compared to AL, CR50 rats had reduced the main risk factors for CD. Moreover, the FR50 rats showed increased cardiac function both at baseline conditions (45% > AL rats) and during the post-ischemic period (60% > AL rats) which may be explained by a decreased cardiac oxidative stress and increased HSP72 content. Conclusion: SCR from birth to adult age reduced risk factors for CD, increased basal cardiac function and protected hearts from the I/R, possibly by a mechanism involving ROS. [ABSTRACT FROM AUTHOR]

In recent years, new textile materials have been developed through the use of nanotechnology-based tools. The development of textile surfaces with self-cleaning properties has a large combined potential to reduce the environmental impact related to pollution. In this research work, three types of textiles substrates (cotton, Entretela, and polylactic acid (PLA)) were functionalized with titanium dioxide nanoparticles (TiO2) using chemical and mechanical processes (padding). During the functionalization process, two different methods were used, both of which allowed a good fixation of nanoparticles of TiO2 on textile substrates. The samples were examined for morphology and for photocatalytic properties under visible light irradiation. A study aimed at evaluating the effect of pH of the aqueous solution of TiO2 nanoparticles was performed in order to promote interaction between TiO2 and the dye solution rhodamine B (Rh-B). The TiO2 nanoparticles were characterized by X-ray diffraction (XRD). The measurement of the zeta potential of the TiO2 nanoparticle solution proved to be always positive and have low colloidal stability. Chromatography (HPLC and GC-MS) analyses confirm that oxalic acid is the intermediate compound formed during the photodegradation process. [ABSTRACT FROM AUTHOR]

Intervals without prey during the fifth instar and nutrient quality may affect reproduction, longevity, and weight of the zoophytophagous predator Brontocoris tabidus (Heteroptera: Pentatomidae: Asopinae). This asopine was reared on Eucalyptus urophylla (Myrtaceae) trees under field conditions at 23 ± 6 73176;C, 76 ± 9 % RH and 13:11 (dark:light) h photoperiod. The experiment was developed with 60 B. tabidus nymphs individualized in organza bags (31 cm long × 21 cm diameter). One group of nymphs received only Tenebrio molitor (Coleoptera: Tenebrionidae) pupae and water without E. urophylla trees (T1). Other nymphs were reared on E. urophylla trees and fed with T. molitor pupae and water during the second, third, and fourth instars and twenty of them per group after zero, five, and 10 days from the beginning of the fifth instar making up the treatments T2, T3, and T4, respectively. The period without prey increased duration of the fifth instar for males in the T3 and T4 while female weight was lower in the T4. The oviposition period was shorter and the number of egg masses of B. tabidus was lower in the T1 than in the T2, T3, and T4. The highest egg numbers were found in the T2 and T3 with about 4 times more eggs than in the T1. The number of nymphs was low and the percentage of nymph hatching higher in the T1. The interval of five and 10 days without prey from the beginning of the fifth instar did not affect the duration and survival of this instar and supplementation with E. urophylla increased the reproductive capacity of the predator B. tabidus. [ABSTRACT FROM AUTHOR]

A primary tool of nuclear safeguards authorities for detecting undeclared nuclear activities is environmental sample analysis containing uranium-bearing aerosol particles. SIMS (Secondary Ion Mass Spectrometry) has been established as a powerful technique for performing uranium isotope analysis on safeguards samples. Typically, a screening of the sample for locating the particles of interest is followed by micro-beam measurements of individual particles in order to obtain their precise isotopic composition. The uncertainty of these measurements, in particular for the minor isotopes 234U and 236U, is mainly limited by the counting statistics as the total amount of uranium available is very low, usually less than 1 pg. This uncertainty can be reduced when recording several isotopes simultaneously using a multi-collection system. This has been available commercially for many years and has been used for different applications in geosciences on Large Geometry-SIMS (LG-SIMS) instruments. This paper will describe and discuss how isotope measurements of low content uranium materials can be optimized using a multi-ion counting system consisting of five discrete dynode electron multiplier (EM) detectors. The results obtained for uranium isotope ratios are presented for different measurement protocols: static multi-collector, dynamic multi-collector and single collector measurements. Some of the fundamental properties of the detector system that affect the overall measurement uncertainty are discussed. Best practices are also suggested based on the current experience. [ABSTRACT FROM AUTHOR]