This paper is concerned with the application of porous treatments as a means of flow and aerodynamic noise reduction. An extensive experimental investigation is undertaken to study the effects of ...flow interaction with porous media, in particular in the context of the manipulation of flow over blunt trailing edges and attenuation of vortex shedding. Comprehensive boundary layer and wake measurements have been carried out for a long flat plate with solid and porous blunt trailing edges. Unsteady velocity and surface pressure measurements have also been performed to gain an in-depth understanding of the changes to the energy–frequency content and coherence of the boundary layer and wake structures as a result of the flow interaction with a porous treatment. Results have shown that permeable treatments can effectively delay the vortex shedding and stabilize the flow over the blunt edge via mechanisms involving flow penetration into the porous medium and discharge into the near-wake region. It has also been shown that the porous treatment can effectively destroy the spanwise coherence of the boundary layer structures and suppress the velocity and pressure coherence, particularly at the vortex shedding frequency. The flow–porous scrubbing and its effects on the near-wall and large coherent structures have also been studied. The emergence of a quasi-periodic recirculating flow field inside highly permeable surface treatments has also been investigated. Finally, the paper has identified several important mechanisms concerning the application of porous treatments for aerodynamic and aeroacoustic purposes, which can help more effective and tailored designs for specific applications.
Cold-water immersion (CWI) has been applied widely as a recovery method, but little evidence is available to support its effectiveness.
To investigate the effects of CWI on muscle damage, perceived ...muscle soreness, and muscle power recovery of the upper and lower limbs after jiu-jitsu training.
Crossover study.
Laboratory and field.
A total of 8 highly trained male athletes (age = 24.0 ± 3.6 years, mass = 78.4 ± 2.4 kg, percentage of body fat = 13.1% ± 3.6%) completed all study phases.
We randomly selected half of the sample for recovery using CWI (6.0°C ± 0.5°C) for 19 minutes; the other participants were allocated to the control condition (passive recovery). Treatments were reversed in the second session (after 1 week).
We measured serum levels of creatine phosphokinase, lactate dehydrogenase (LDH), aspartate aminotransferase, and alanine aminotransferase enzymes; perceived muscle soreness; and recovery through visual analogue scales and muscle power of the upper and lower limbs at pretraining, postrecovery, 24 hours, and 48 hours.
Athletes who underwent CWI showed better posttraining recovery measures because circulating LDH levels were lower at 24 hours postrecovery in the CWI condition (441.9 ± 81.4 IU/L) than in the control condition (493.6 ± 97.4 IU/L; P = .03). Estimated muscle power was higher in the CWI than in the control condition for both upper limbs (757.9 ± 125.1 W versus 695.9 ± 56.1 W) and lower limbs (53.7 ± 3.7 cm versus 35.5 ± 8.2 cm; both P values = .001). In addition, we observed less perceived muscle soreness (1.5 ± 1.1 arbitrary units au versus 3.1 ± 1.0 au; P = .004) and higher perceived recovery (8.8 ± 1.9 au versus 6.9 ± 1.7 au; P = .005) in the CWI than in the control condition at 24 hours postrecovery.
Use of CWI can be beneficial to jiu-jitsu athletes because it reduces circulating LDH levels, results in less perceived muscle soreness, and helps muscle power recovery at 24 hours postrecovery.
Biological nitrogen oxide signalling and stress is an area of extreme clinical, pharmacological, toxicological, biochemical and chemical research interest. The utility of nitric oxide and derived ...species as signalling agents is due to their novel and vast chemical interactions with a variety of biological targets. Herein, the chemistry associated with the interaction of the biologically relevant nitrogen oxide species with fundamental biochemical targets is discussed. Specifically, the chemical interactions of nitrogen oxides with nucleophiles (e.g. thiols), metals (e.g. hemeproteins) and paramagnetic species (e.g. dioxygen and superoxide) are addressed. Importantly, the terms associated with the mechanisms by which NO (and derived species) react with their respective biological targets have been defined by numerous past chemical studies. Thus, in order to assist researchers in referring to chemical processes associated with nitrogen oxide biology, the vernacular associated with these chemical interactions is addressed.
Background. An increasing incidence of anal cancer among men suggests a need to better understand anal canal human papillomavirus (HPV) infection among human immunodeficiency virus—negative men. ...Methods. Genotyping for HPV was conducted on cells from the anal canal among men who have sex with women (MSW) and men who have sex with men (MSM), aged 18-70 years, from Brazil, Mexico, and the United States. Factors associated with anal HPV infection were assessed using multivariable logistic regression. Results. The prevalence of any HPV type and oncogenic HPV types did not differ by city. Anal canal HPV prevalence was 12.2% among 1305 MSW and 47.2% among 176 MSM. Among MSW, reporting a lifetime number of ≥ 10 female sex partners, a primary sexual relationship <1 year in duration, and a prior hepatitis B diagnosis were independently associated with detection of any anal HPV in multivariable analysis. Among MSM, a younger age, reporting ≥2 male anal sex partners in the past 3 months, and never using a condom for anal sex in the past 6 months were independently associated with detection of any anal HPV in multivariable analysis. Conclusions. Number of sex partners was associated with anal HPV infection in both MSW and MSM. Anal HPV infection in men may be mediated by age, duration of sexual relationship, and condom use.
This laboratory experiment was divided into four parts. In the first part, students evaluate previously published data and check their normality using histograms, Q–Q plots, the Shapiro–Wilk test, ...and boxplots. In the second part, two different groups were compared. First, data normality and homoskedasticity were checked by using the Shapiro–Wilk test and Levene’s test, respectively. Then the group mean was compared using the Student, Welch, and Mann–Whitney tests. In the third part, the famous Iris flower data set was analyzed, where data normality and homoskedasticity were checked. Then, three independent groups were compared using ANOVA, without correction, and using the Welch and Brown-Forsythe corrections. The Iris flowers data set was also compared using the nonparametric version of ANOVA (Kruskal–Wallis test) and post hoc tests such as the Tukey test (parametric) and Dunn’s test (nonparametric). In the fourth part, students measured the density of water using four pieces of glassware (a beaker, a graduated cylinder, a volumetric pipet, and a graduated pipet). After the experiment, the data’ normality and homoskedasticity were checked. Then, the data was compared using ANOVA and post hoc tests. The results of these tests were visually interpreted using raincloud and discriminant plots. These data provide a starting point for teaching precision, accuracy, descriptive statistics, and hypothesis tests. Statistical analysis was carried out using Jeffreys’s Amazing Statistics Program (JASP), which is free and open-source software that provides several graphical interpretations of the hypothesis test.
Understanding decision‐making in complex and dynamic environments is relevant for designing strategies targeting safety improvements and error rate reductions. However, studies evaluating brain ...dynamics in realistic situations are scarce in the literature. Given the evidence that specific microstates may be associated with perception and attention, in this work we explored for the first time the application of the microstate model in an ecological, dynamic and complex scenario. More specifically, we evaluated elite helicopter pilots during engine‐failure missions in the vicinity of the so called “dead man's curve,” which establishes the operational limits for a safe landing after the execution of a recovery maneuver (autorotation). Pilots from the Brazilian Air Force flew a AS‐350 helicopter in a certified aerodrome and physiological sensor data were synchronized with the aircraft's flight test instrumentation. We assessed these neural correlates during maneuver execution, by comparing their modulations and source reconstructed activity with baseline epochs before and after flights. We show that the topographies of our microstate templates with 4, 5, and 6 classes resemble the literature, and that a distinct modulation characterizes decision‐making intervals. Moreover, the source reconstruction result points to a differential activity in the medial prefrontal cortex, which is associated to emotional regulation circuits in the brain. Our results suggest that microstates are promising neural correlates to evaluate realistic situations, even in a challenging and intrinsically noisy environment. Furthermore, it strengthens their usage and expands their application for studying cognition under more realistic conditions.
Microstates are feasible neural correlates in challenging and intrinsically noisy environments.
Microstate templates recovered in a challenging experimental condition resemble previous reports in controlled environments.
Microstate dynamics is modulated by cognitive activities. In particular, piloting activity during the maneuver to recover a falling helicopter does not modulate Microstate D, traditionally associated with the cognitive control and attention networks, but Microstate F, which involves the medial prefrontal cortex. This microstate class is potentially associated with the emotional regulation network.
Gelatin was obtained from cobia (Rachycentron canadum) skins, which is an important commercial species for marine fish aquaculture, and it was compared with gelatin from croaker (Micropogonias ...furnieri) skins, using the same extraction methodology (alkaline/acid pre-treatments). Cobia skins gelatin showed values of protein yield, gelatin yield, gel strength, melting point, gelling point and viscosity higher than the values found from croaker skins gelatin. The values of turbidity and Hue angle for cobia and croaker gelatins were 403 and 74 NTU, and 84.8° and 87.3°, respectively. Spectra in the infrared region had the major absorption band in the amide region for both gelatins, but it showed some differences in the spectra. The proline and hydroxyproline contents from cobia skins gelatin (205 residues/1000 residues) was higher than from croaker skins gelatin (188 residues/1000 residues). SDS-PAGE of both gelatins showed a similar molecular weight distribution to that of standard collagen type I. Therefore, cobia skins could be used as a potential marine source of gelatin obtainment for application in diversified industrial fields.
•Gelatin was obtained from cobia skins, and it was compared with gelatin from croaker.•Cobia (Rachycentron canadum) is an important commercial species of the marine aquaculture.•Cobia gelatin showed yield and gel properties higher than croaker gelatin.•The amino acids content in cobia gelatin was higher than in croaker gelatin.•Cobia skins showed as a source of gelatin obtainment for industrial application.
In this work, we explore some exciting details of the time-dependent regime in long-range systems under mean-field approximation compared to the critical dynamics of the short-range systems. Firstly, ...we discuss some mechanisms of the initial anomalous behavior of the magnetization via two and three-dimensional Monte Carlo simulations to later compare with results from mean-field simulations in both: spin 1/2 and spin 1 (Blume–Capel) Ising models. We also investigate the distinction between critical and tricritical points and the corresponding crossover. For a complete analysis, we performed short-time simulations in the mean-field regime to determine the critical temperatures optimizing power laws and the critical exponents of the different points. We independently calculated these exponents, i.e., without using previous exponents estimates from literature/theory. Our investigations corroborate the analytical results here also developed.
Store-operated Ca(2+) entry (SOCE) is a ubiquitous and essential mechanism regulating Ca(2+) homeostasis in all tissues, and controls a wide range of cellular functions including keratinocyte ...differentiation, osteoblastogenesis and osteoclastogenesis, T cell proliferation, platelet activation, and muscle contraction. The main SOCE actors are STIM1 and ORAI1. Depletion of the reticular Ca(2+) stores induces oligomerization of the luminal Ca(2+) sensor STIM1, and the oligomers activate the plasma membrane Ca(2+) channel ORAI1 to trigger extracellular Ca(2+) entry. Mutations in STIM1 and ORAI1 result in abnormal SOCE and lead to multi-systemic disorders. Recessive loss-of-function mutations are associated with CRAC (Ca(2+) release-activated Ca(2+)) channelopathy, involving immunodeficiency and autoimmunity, muscular hypotonia, ectodermal dysplasia, and mydriasis. In contrast, dominant STIM1 and ORAI1 gain-of-function mutations give rise to tubular aggregate myopathy and Stormorken syndrome (TAM/STRMK), forming a clinical spectrum encompassing muscle weakness, thrombocytopenia, ichthyosis, hyposplenism, short stature, and miosis. Functional studies on patient-derived cells revealed that CRAC channelopathy mutations impair SOCE and extracellular Ca(2+) influx, while TAM/STRMK mutations induce excessive Ca(2+) entry through SOCE over-activation. In accordance with the opposite pathomechanisms underlying both disorders, CRAC channelopathy and TAM/STRMK patients show mirror phenotypes at the clinical and molecular levels, and the respective animal models recapitulate the skin, bones, immune system, platelet, and muscle anomalies. Here we review and compare the clinical presentations of CRAC channelopathy and TAM/STRMK patients and the histological and molecular findings obtained on human samples and murine models to highlight the mirror phenotypes in different tissues, and to point out potentially undiagnosed anomalies in patients, which may be relevant for disease management and prospective therapeutic approaches.
Our purpose was to evaluate the effect of physically active lessons (PAL) on the cognitive performance of children during two years of follow-up. Four classes (second grade of elementary school) were ...divided into two intervention classes (n = 34) and two control classes (n = 27). Evaluations were performed before the intervention (M1), after 3 (M2) and 9 (M3) months in the 1st year, and 14 (M4) and 18 (M5) months in the 2nd year. The intervention was based on PAL integrated with the curricular components, which stimulated the children to stand or move in the classroom. Cognitive performance was evaluated using three computerized tests for response inhibition, selective attention, and cognitive flexibility. The children in the intervention classes presented improved cognitive performance in the execution of all tasks along the two years follow-up, in both correct answers and time reactions, with exception of correct answers of visual search. For the intervention classes, in most of the tasks, the mean differences confidence interval of 95% did not include the 0 on the two last moments of evaluation, and in all cases, the mean differences of them between M1 versus M5 were significantly different with high values of effect size (cohen -d > 1). PAL promotes modest improvements in diverse cognitive functions in children.
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