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Direct numerical simulations (DNS) of spatially evolving turbulent planar jets of viscoelastic fluids described by the FENE-P model, such as those consisting of a Newtonian fluid solvent carrying long chain polymer molecules, are carried out in order to develop a theory for the far field of turbulent jets of viscoelastic fluids. New evolution relations for the jet shear-layer thickness
, centreline velocity
and maximum polymer stresses
are derived and validated by the new DNS data, yielding
, respectively, where
is the coordinate in the streamwise direction. It is shown that, compared with a classical (Newtonian) turbulent jet, the effect of the polymers is to reduce the spreading rate, centreline velocity decay, Reynolds stresses and viscous dissipation rate. The self-preserving character of the flow is analysed and it is shown that profiles of mean velocity, Reynolds stresses and polymer stresses are self-similar provided the proper scales are used in the normalisation of these quantities. A fundamental difference from the Newtonian jet in this regard is the necessity for two, instead of only one, different velocity and length scales to properly characterise the evolution of the turbulent flow. These extra velocity and length scales are directly related to a time scale associated with the characteristic fading memory property of viscoelastic fluids.
Litter size reduction can induce early overnourishment, being an attractive experimental model to study short- and long-term consequences of childhood obesity. Epidemiological data indicate sex differences regarding cardiometabolic disorders and hypertrophic cardiomyopathy. The present study aimed to describe biometric, nutritional and cardiovascular changes related to neonatal overweight promoted by litter size reduction in young and adult Wistar rats of both sexes. Litter adjustment to eight or four pups/mother (1:1 male-to-female ratio) gave, respectively, control and overweight groups. Body mass, food intake, haemodynamic and echocardiographic parameters and cardiorespiratory capacity were evaluated at postnatal days 30 and 150. Diminished litters were correlated with higher body mass and weight gain (12 %) during lactation, validating the experimental model of neonatal overweight. Soon after weaning male (16 %) and female (25 %) offspring of these litters presented a lower food intake than their respective control, without differences in body mass. Adult males from reduced litters presented higher abdominal circumference (7 %), systolic blood pressure (10 %), interventricular septum thickness (15 %) and relative wall thickness (15 %) compared with their respective control. Rats' performance on the maximal effort ergometer test was not affected by neonatal overweight. Data suggest the occurrence of catch-down growth and hypophagia in male and female rats submitted to neonatal overweight. However, only male rats presented haemodynamic and cardiac structural changes. These findings are crucial to personalised/gender medicine.
The co-infection between visceral leishmaniasis (VL) and human immunodeficiency virus (HIV) has increased in several countries in the world. The current serological tests are not suitable since they present low sensitivity to detect the most of VL/HIV cases, and a more precise diagnosis should be performed. In this context, in the present study, an immunoproteomics approach was performed using Leishmania infantum antigenic extracts and VL, HIV and VL/HIV patients sera, besides healthy subjects samples; aiming to identify antigenic markers for these clinical conditions. Results showed that 43 spots were recognized by antibodies in VL and VL/HIV sera, and 26 proteins were identified by mass spectrometry. Between them, β-tubulin was expressed, purified and tested in ELISA experiments as a proof of concept for validation of our immunoproteomics findings and results showed high sensitivity and specificity values to detect VL and VL/HIV patients. In conclusion, the identified proteins in the present work could be considered as candidates for future studies aiming to improvement of the diagnosis of VL and VL/HIV co-infection.
The effects of cold atmospheric plasma (CAP) of dielectric barrier discharges on the wettability, imbibition and germination of Leucaena leucocephala were investigated. It was established that CAP treatment markedly hydrophilized the seed coat, especially at longer treatment times. From the profile of the imbibition curve and visual observation, it was possible to verify that there are two resistance barriers to water penetration: integument surface and region of the macrosclereid cell wall (light line). Although the plasma interacts only in the integument, increasing the density of hydrophilic sites increases the capacity of water absorption, producing enough driving force to overcome the second resistance barrier. The existence of these two barriers changes the three-phase pattern generally observed during seed germination. Despite an increase in imbibition, the plasma treatment conditions used in this work, were not enough to overcome completely the dormancy barrier.
Tuberous sclerosis complex is a rare genetic disorder leading to the growth of hamartomas in multiple organs, including cardiac rhabdomyomas. Children with symptomatic cardiac rhabdomyoma require frequent admissions to intensive care units, have major complications, namely, arrhythmias, cardiac outflow tract obstruction and heart failure, affecting the quality of life and taking on high healthcare cost. Currently, there is no standard pharmacological treatment for this condition, and the management includes a conservative approach and supportive care. Everolimus has shown positive effects on subependymal giant cell astrocytomas, renal angiomyolipoma and refractory seizures associated with tuberous sclerosis complex. However, evidence supporting efficacy in symptomatic cardiac rhabdomyoma is limited to case reports. The ORACLE trial is the first randomised clinical trial assessing the efficacy of everolimus as a specific therapy for symptomatic cardiac rhabdomyoma.
ORACLE is a phase II, prospective, randomised, placebo-controlled, double-blind, multicentre protocol trial. A total of 40 children with symptomatic cardiac rhabdomyoma secondary to tuberous sclerosis complex will be randomised to receive oral everolimus or placebo for 3 months. The primary outcome is 50% or more reduction in the tumour size related to baseline. As secondary outcomes we include the presence of arrhythmias, pericardial effusion, intracardiac obstruction, adverse events, progression of tumour reduction and effect on heart failure.
ORACLE protocol addresses a relevant unmet need in children with tuberous sclerosis complex and cardiac rhabdomyoma. The results of the trial will potentially support the first evidence-based therapy for this condition.
The BW has been largely used as a selection criterion in genetic selection programmes; however, increases in BW can affect animal metabolism and metabolites. The knowledge of how genetic potential for growth affects the metabolites can give a footprint of growth metabolism. This research aimed to evaluate the effect of genetic potential for post-weaning growth (GG) on performance, carcass traits and serum metabolome of non-castrated Nellore males during the finishing phase. Forty-eight Nellore non-castrated males, with divergent potential for post-weaning growth, were selected and divided into two groups: high potential for post-weaning growth (HG; n = 24) and low potential for post-weaning growth (LG; n = 24). Animals were kept and fed for 90 days where performance and ultrasound carcass traits were evaluated. Blood samples were collected at the beginning and end of feeding period to analyse serum metabolites concentration. The hot carcass weight and dressing percentage were recorded at slaughter. The feedlot performance and carcass traits were not affected by genetic potential. The HG animals had a lower glucose (P = 0.039), glutamate (P = 0.038), glutamine (P = 0.004), greater betaine (P = 0.039) and pyruvate (P = 0.039) compared to the LG group at the beginning of feedlot. In addition, higher creatine phosphate concentrations were observed at the beginning of feeding period, compared to final, for both groups (P = 0.039). In conclusion, the genetic potential for post-weaning growth does not affect performance and carcass traits during the finishing period. Differences in metabolite concentrations can be better found at the beginning of feedlot, providing a footprint of growth metabolism, but similar metabolite concentration at the end of finishing period.
Light competition increases and plants’ growth pattern change to optimize light utilization when the leaf area index increases. It has been previously shown that using 95% canopy light interception (LI) as a grazing frequency criterion resulted in a greater proportion of leaves and a lower proportion of stem. The objective of the study was to characterize the forage production, morphological composition and nutritive value of Panicum maximum cv Mombaça. The experiment was carried out during summer, autumn–winter and spring. Treatments corresponded to combinations of two pre-grazing conditions (95% and maximum LI at pre-grazing; LI95% and LIMax, respectively) and two post-grazing heights (PGHs; 30 and 50 cm). The statistical design was a randomized complete block, with a 2 × 2 factorial arrangement. Swards managed with LI95% had greater proportions of leaves and lower proportions of stems compared to LIMax. Leaf proportion was lower during autumn–winter compared to summer and spring. The LI95% had greater crude protein (CP) and digestibility (IVOMD), and lower acid detergent fibre (ADF) concentrations than LIMax. The 50 cm PGH pastures had greater CP content and IVOMD, and lower ADF content than 30 cm PGH pastures. Lower IVOMD was observed during autumn–winter than summer and spring. The variability observed on morphological characteristics was primarily associated with seasonality, whilst the nutritive value was primarily affected by grazing management. The pre-grazing target of LI95% combined with 50 cm PGH was the combination that resulted in an increased proportion of leaves, decreased stems in basal stratum and the greatest nutritive value of the produced forage.
Cognitive tests of inhibitory control show variable results for the differential diagnosis between behavioural variant of Frontotemporal Dementia (bvFTD) and Alzheimer’s disease (AD). We compared the diagnostic accuracies of tests of inhibitory control and of a behavioural questionnaire, to distinguish bvFTD from AD.
Three groups of participants were enrolled: 27 bvFTD patients, 25 AD patients, and 24 healthy controls. Groups were matched for gender, education, and socio-economic level. Participants underwent a comprehensive neuropsychological assessment of inhibitory control, including Hayling Test, Stroop, the Five Digits Test (FDT) and the Delay Discounting Task (DDT). Caregivers completed the Barratt Impulsiveness Scale 11th version (BIS-11).
bvFTD and AD groups showed no difference in the tasks of inhibitory control, while the caregiver questionnaire revealed that bvFTD patients were significantly more impulsive (BIS-11: bvFTD 76.1+9.5, AD 62.9+13, p < .001).
Neuropsychological tests of inhibitory control failed to distinguish bvFTD from AD. On the contrary, impulsivity caregiver-completed questionnaire provided good distinction between bvFTD and AD. These results highlight the current limits of cognitive measures of inhibitory control for the differential diagnosis between bvFTD and AD, whereas questionnaire information appears more reliable and in line with clinical diagnostics.
Chagas disease (CD) is a neglected parasitic condition endemic in the Americas caused by Trypanosoma cruzi. Patients present an acute phase that may or not be symptomatic, followed by lifelong chronic stage, mostly indeterminate, or with cardiac and/or digestive progressive lesions. Benznidazole (BZ) and nifurtimox are the only drugs approved for treatment but not effective in the late chronic phase and many strains of the parasite are naturally resistant. New alternative therapy is required to address this serious public health issue. Repositioning and combination represent faster, and cheaper trial strategies encouraged for neglected diseases. The effect of imatinib (IMB), a tyrosine kinase inhibitor designed for use in neoplasias, was assessed in vitro on T. cruzi and mammalian host cells. In comparison with BZ, IMB was moderately active against different strains and forms of the parasite. The combination IMB + BZ in fixed-ratio proportions was additive. Novel 14 derivatives of IMB were screened and a 3,2-difluoro-2-phenylacetamide (3e) was as potent as BZ on T. cruzi but had low selectivity index. The results demonstrate the importance of phenotypic assays, encourage the improvement of IMB derivatives to reach selectivity and testify to the use of repurposing and combination in drug screening for CD.
The average patterns of the velocity and scalar fields near turbulent/non-turbulent interfaces (TNTI), obtained from direct numerical simulations (DNS) of planar turbulent jets and shear free turbulence, are assessed in the strain eigenframe. These flow patterns help to clarify many aspects of the flow dynamics, including a passive scalar, near a TNTI layer, that are otherwise not easily and clearly assessed. The averaged flow field near the TNTI layer exhibits a saddle-node flow topology associated with a vortex in one half of the interface, while the other half of the interface consists of a shear layer. This observed flow pattern is thus very different from the shear-layer structure consisting of two aligned vortical motions bounded by two large-scale regions of uniform flow, that typically characterizes the average strain field in the fully developed turbulent regions. Moreover, strain dominates over vorticity near the TNTI layer, in contrast to internal turbulence. Consequently, the most compressive principal straining direction is perpendicular to the TNTI layer, and the characteristic 45-degree angle displayed in internal shear layers is not observed at the TNTI layer. The particular flow pattern observed near the TNTI layer has important consequences for the dynamics of a passive scalar field, and explains why regions of particularly high scalar gradient (magnitude) are typically found at TNTIs separating fluid with different levels of scalar concentration. Finally, it is demonstrated that, within the fully developed internal turbulent region, the scalar gradient exhibits an angle with the most compressive straining direction with a peak probability at around 20
. The scalar gradient and the most compressive strain are not preferentially aligned, as has been considered for many years. The misconception originated from an ambiguous definition of the positive directions of the strain eigenvectors.
Graded exercises tests are performed in adult populations; nonetheless, the use of this type of assessment is greatly understudied in overweight and obese adolescents.
To investigate heart rate autonomic responses to submaximal aerobic exercise in obese and overweight adolescents.
We recruited 40 adolescents divided into two groups: (1) overweight group comprising 10 boys and 10 girls between Z-score +1 and +2 and (2) obese group comprising 10 boys and 10 girls above Z-score >+2. Heart rate variability was analysed before (T1) and after exercise (T2–T4) on treadmill at a slope of 0%, with 70% of the maximal estimated heart rate (220 – age) for 20 minutes.
Heart rate in the overweight group was: 93.2±10.52 bpm versus 120.8±13.49 bpm versus 94.6±11.65 bpm versus 93.0±9.23 bpm, and in the obese group was: 92.0±15.41 bpm versus 117.6±16.31 bpm versus 92.1±12.9 bpm versus 91.8±14.33 bpm. High frequency in the overweight group was: 640±633.1 ms2 versus 84±174.66 ms2 versus 603.5±655.31 ms2 versus 762.6±807.21 ms2, and in the obese group was: 628.4±779.81 ms2 versus 65.4±119.34 ms2 versus 506.2±482.70 ms2 versus 677.9±939.05 ms2; and root mean square of successive differences in the overweight group was: 37.9±18.81 ms versus 10.9±8.41 ms versus 32.8±24.07 ms versus 36.7±21.86 ms, and in the obese group was: 38.7±23.17 ms versus 11.5±8.62 ms versus 32.3±16.74 ms versus 37.3±24.21 ms. These values significantly changed during exercise compared with resting values in overweight and obese groups. Moreover, we also reported no significant difference of resting parasympathetic control of heart rate between obese and overweight adolescents.
There was no significant difference of autonomic responses elicited by submaximal aerobic exercise between overweight and obese adolescents.
We evaluated the effects of cattle manure and inoculation with arbuscular mycorrhizal fungi (AMF) in maize plants growing in a semiarid area of Brazilian north-east in 2012 and 2013. Three isolates of AMF (Acaulosporalongula URM-FMA 07 and URM-FMA 03, Claroideoglomusetunicatum UNIVASF 06A) were used, with or without the application of cattle manure, during two growing cycles. In the first year, significant effects of inoculation were detected for straw yield only when the manure was applied. In the second year, there was an interaction between fertilisation and inoculation for plant height and grain yield, with the highest values in the fertilised treatments. Inoculation with A. longula demonstrated that mycorrhizal inoculation in field-grown plants could be an alternative management for improving plant growth and grain yield, reducing the use of cattle manure. The AMF sporulation and mycorrhizal colonisation were improved after inoculation, and A. longula URM-FMA 07 increased sporulation by more than 15 times while inoculation with C. etunicatum increased sporulation by more than 3 times. The mycorrhizal inoculation is a management practice that can be useful for recovering or maintaining AMF infective propagules in soil, showing potential to be used in large-scale field conditions in Brazilian semiarid. Although mycorrhisation presents high agricultural relevance due to benefits promoted to the soil and plants, the knowledge about the factors influencing the interactions among microorganisms, soil and plants need to be broadened aiming to achieve successful crop management in semiarid regions.
The increase of sheep meat competitiveness in international markets can be attributed to the rise of the quantity and the improvement of the quality of the edible portion of sheep carcasses. Usually, carcass yield is established after the slaughter of the animals. Yet, when carcass yield is determined in vivo, it can be both a costly and subjective method. This study proposes models for predicting the physical characteristics of lamb carcass using bioimpedance analysis (BIA) in live animals. Thirty-one Texel × Ile de France crossbreed ram lambs were slaughtered at 20, 26, 32 or 38 kg of BW. Before the slaughter, values of resistance (Rs) and reactance (Xc) were collected using a single-frequency BIA equipment (Model RJL Quantum II Bioelectrical Body Composition Analyzer). Then, BIA main variables such as body bioelectrical volume (V), phase angle (PA), resistive density (RsD) and reactive density (XcD) were calculated. After slaughter, cold carcass weight (CCW), cold carcass yield (CCY), subcutaneous fat thickness (SFT), soft tissue weight (STW) and soft tissue yield (STY) were also measured. Multiple regression analyses were carried out using the physical characteristics as dependent variables and the bioimpedance values as independent variables. Predictive performance of the models was assessed using leave-one-out cross-validation. The prediction model of CCW was obtained using the V, PA and RsD (R2 = 0.97), STW through the V, RsD and XcD (R2 = 0.97), CCY by Rs, Z and XcD (R2 = 0.69), STY by V and XcD (R2 = 0.67), and SFT only for XcD (R2 = 0.84). The results indicated that BIA has the potential to predict carcass characteristics of lambs at different body masses.
Salivary molecules, as glycine-rich proteins (GRPs), are essential to tick attachment and feeding on the host and are suggested to be involved in the host's immune system evasion, therefore representing natural candidates in the search for protective vaccine antigens. This work shows the molecular characterization of a GRP from Rhipicephalus microplus (RmGRP). The cDNA and putative amino acid sequences were analysed, as well as the transcription level in tick tissues/developmental stages, showing the highest levels of gene expression in 1-day-old larvae and salivary glands of fully engorged females. RmGRP gene silencing resulted in a lower hatching rate of larvae from treated females. In addition, recombinant RmGRP (rRmGRP) was recognized by sera from naturally and experimentally infested bovines, displaying considerable differences among the individuals tested. rRmGRP was recognized by anti-saliva and anti-salivary glands sera, while anti-rRmGRP serum recognized RmGRP in saliva and salivary glands, indicating its secretion into the host. The data collected indicate that RmGRP may present roles other than in the tick–host relationship, especially in embryo development. In addition, the high expression in adult females, antigenicity and presence of shared characteristics with other tick protective GRPs turns RmGRP a potential candidate to compose an anti-tick vaccine cocktail.
HR 6902 was the first target of a systematic study by Griffin (1986, JApA, 7, 195) of binaries showing composite spectra. It is also a well-studied member of the ζ Aur class. ζ Aur systems are long-period eclipsing binaries that are comprised of an evolved giant primary and a hot dwarf companion. Although those component stars have very different effective temperatures they have similar luminosities in the blue and near-UV regions, and hence display a composite spectrum at those wavelengths. In principle the ζ Aur systems are excellent tests of evolutionary and structural stellar models. In recent years the somewhat fragmentary eclipse photometry of HR 6902 has been out-classed by the high-precision continuous monitoring by the space mission CoRoT. HR 6902 was selected as a primary target of its seismology field, because the possible detection of solar-like pulsations in a giant component of a double-lined eclipsing binary could help to calibrate the scaling relation of giant pulsators. Our poster reported the results of a new analysis based on the CoRoT observations and follow-up spectroscopy with HARPS at the ESO 3.6-m telescope at La Silla.
The unprecedented accuracy of the CoRoT photometry enabled us to:
improve drastically the accuracy of the binary orbit and stellar parameters (by a factor ~10 for the radii)
extend the test of validity/calibration of the scaling relations to high stellar mass and radius, and put constraints on the evolutionary state (particularly since this binary is certainly free from tidal effects).
The scaling of turbulent motions is investigated by considering the flow in the eigenframe of the local strain-rate tensor. The flow patterns in this frame of reference are evaluated using existing direct numerical simulations of homogeneous isotropic turbulence over a Reynolds number range from
up to 1131, and also with reference to data for inhomogeneous, anisotropic wall turbulence. The average flow in the eigenframe reveals a shear layer structure containing tube-like vortices and a dissipation sheet, whose dimensions scale with the Kolmogorov length scale,
. The vorticity stretching motions scale with the Taylor length scale,
, while the flow outside the shear layer scales with the integral length scale,
. Furthermore, the spatial organization of the vortices and the dissipation sheet defines a characteristic small-scale structure. The overall size of this characteristic small-scale structure is
in all directions based on the coherence length of the vorticity. This is considerably larger than the typical size of individual vortices, and reflects the importance of spatial organization at the small scales. Comparing the overall size of the characteristic small-scale structure with the largest flow scales and the vorticity stretching motions on the scale of
shows that transitions in flow structure occur where
and 250. Below these respective transitional Reynolds numbers, the small-scale motions and the vorticity stretching motions are progressively less well developed. Scale interactions are examined by decomposing the average shear layer into a local flow, which is induced by the shear layer vorticity, and a non-local flow, which represents the environment of the characteristic small-scale structure. The non-local strain is
in width and height, which is consistent with observations in high Reynolds number flow of a
wide instantaneous shear layer with many
-scale vortical structures inside (Ishihara et al., Flow Turbul. Combust., vol. 91, 2013, pp. 895–929). In the average shear layer, vorticity aligns with the intermediate principal strain at small scales, while it aligns with the most stretching principal strain at larger scales, consistent with instantaneous turbulence. The length scale at which the alignment changes depends on the Reynolds number. When conditioning the flow in the eigenframe on extreme dissipation, the velocity is strongly affected over large distances. Moreover, the associated peak velocity remains Reynolds number dependent when normalized by the Kolmogorov velocity scale. It signifies that extreme dissipation is not simply a small-scale property, but is associated with large scales at the same time.
Cepheids are excellent stellar tracers: they are bright enough to be observed even at large distances; their distances can be accurately determined via period-luminosity relations; their spectra contain numerous lines that enable us to derive abundances for many α, iron-peak or neutron-capture elements. Classical Cepheids are yellow supergiants that trace the young populations (⩽ 300 Myr); Type II Cepheids are post Horizontal Branch, low-mass, Population II stars (⩾ 10 Gyr). Both can be used for many purposes in Milky Way archaeology.
Plants’ ability to rebuild their tiller population is affected by weather changes and management strategies. The hypothesis of the present study was that frequency and severity of defoliation alter Mulato grass (Brachiaria ruziziensis × Brachiaria brizantha cv. Marandu) sward development, and the proportion of aerial and basal tillers, interfering with sward stability. The objective was to evaluate aerial, basal and total tiller population density and changes in tillering dynamics. Treatments corresponded to strategies of rotational grazing characterized by combinations between two pre-grazing (95% and maximum canopy light interception during regrowth; LI95% and LIMax) and two post-grazing conditions (15 and 20 cm stubble height). The experimental period comprised four seasons of the year: summer 2008 (February–March 2008); autumn–early spring (April to mid-November 2008); late spring (mid-November–December 2008); and summer 2009 (January–March 2009). Density of aerial tillers decreased from summer 2008 to late spring. Tiller death decreased from summer 2008 to autumn–early spring. Aerial and total tiller death increased from late spring to summer 2009, mainly for the LI95% treatment. No differences were observed in the tiller population stability index of aerial tillers for LI treatments or post-grazing heights. The balance between tiller appearance and death for basal tillers remained relatively stable from summer 2008 to late spring. For aerial tillers the balance decreased to negative values from summer 2008 to autumn–early spring for both LI treatments. For total tiller population, the balance decreased to negative values from summer 2008 to autumn–early spring. Results indicated a strong seasonal effect on Mulato grass tillering and growth. Tillering dynamics were affected primarily by grazing frequency, which changed the relative importance of basal and aerial tillers. The results suggested that basal tillering was the predominant perennation pathway.
The mechanical behavior of superconductor lamellar-like BaFe2As2 single crystals was investigated at nanoscale by instrumented indentation. The unique responses of the ab- and a(b)c-crystallographic planes were discussed based on their influence in hardness (H) and elastic modulus (E). The results allowed two main conclusions. (i) The choice of testing parameters strongly affected the scaling of mechanical properties on the lamellar surfaces. Lamellar cracking was the leading mechanism of deformation, featuring a brittle-like behavior and affecting considerably H and E. However, the plastic deformation history allowed different elastic–plastic responses on the ab-plane owing to the compaction of the material. Threshold loads for cracking depended on both loading rate and penetration velocity, pointing out to time-dependent plastic deformation mechanisms. (ii) Proper estimates were achieved for H in multiple loading tests [3.4 GPa for ab- and ∼1 GPa for a(b)c-planes], and for E under loads less than 3 mN (∼55 GPa for both planes).