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The nonlinear mechanism in the self-sustaining process (SSP) of wall-bounded turbulence is investigated. Resolvent analysis is used to identify the principal forcing mode that produces the maximum amplification of the velocities in numerical simulations of the minimal channel for the buffer layer and a modified logarithmic (log) layer. The wavenumbers targeted in this study are those of the fundamental mode, which is infinitely long in the streamwise direction and once-periodic in the spanwise direction. The identified mode is then projected out from the nonlinear term of the Navier–Stokes equations at each time step from the simulation of the corresponding minimal channel. The results show that the removal of the principal forcing mode of the fundamental wavenumber can inhibit turbulence in both the buffer and log layer, with the effect being greater in the buffer layer. Removing other modes instead of the principal mode of the fundamental wavenumber only marginally affects the flow. Closer inspection of the dyadic interactions in the nonlinear term shows that contributions to the principal forcing mode come from a limited set of wavenumber interactions. Using conditional averaging, the flow structures that are responsible for generating the nonlinear interaction to self-sustain turbulence are identified as spanwise rolls interacting with oblique streaks. This method, based on the equations of motion, validates the similarities in the SSP of the buffer and log layer, and characterises the underlying quadratic interactions in the SSP of the minimal channel.
Previous studies attest that early bilinguals can modify their perceptual identification according to the fine-grained phonetic detail of the language they believe they are hearing. Following Gonzales et al. (2019), we replicate the double phonemic boundary effect in late learners (LBs) using conceptual-based cueing. We administered a forced choice identification task to 169 native English adult learners of Spanish in two sessions. In both sessions, participants identified the same /b/-/p/ voicing continuum, but language context was cued conceptually using the instructions. The data were analyzed using Bayesian multilevel regression. Learners categorized the continuum in a similar manner when they believed they were hearing English. However, when they believed they were hearing Spanish, “voiceless” responses increased as a function of L2 proficiency. This research demonstrates the double phonemic boundary effect can be conceptually cued in LBs and supports accounts positing selective activation of independent perception grammars in L2 learning.
Poor adherence to antipsychotics is a major problem in long term treatment of schizophrenia, a relationship between poor adherence and relapse is well documented in the literature. One of the factors that may affect compliance is antipsychotic formulation. The primary objective of the study was to compare patient preference for olanzapine conventional tablet (OCT) with orodispersible tablet (ODT) as measured by a formulation preference question.
A 12-week open label, randomized, crossover, multinational study (Turkey, Romania, Israel, Brazil, Mexico) conducted to estimate the proportion of patients preferring OCT over ODT after 6 weeks of treatment with each formulation. Outpatients with stable schizophrenia (CGI-S<4) on OCT monotherapy for at least 1 month before study inclusion were randomized 1:1. Compliance, drug attitude were measured using DAI-10 and MAF scales; tolerability and safety by AMDP-5 questionnaire and adverse event summary.
From 265 randomized patients,207 were eligible for the analysis and 175 patients answered the preference question. 106(61%) patients preferred ODT, and 48(27%) preferred OCT (p<0.001 adjusted for treatment sequence); 21(12%) expressed no preference. 90% of patients were rated as almost always compliant on both formulations. The adverse event profiles of ODT and OCT were similar: most common (>1%) adverse events were weight increase, hypertriglyceridaemia, and somnolence.
Most of the patients who answered the preference question declared to prefer olanzapine orodispersible to conventional formulation. Given the importance of patient's preference as one of the factors for future compliance, olanzapine orodispersible tablet could be a good choice.
First described as a case series by Pryse-Phillips in 1971, Olfactory Reference Syndrome (ORS) has been increasingly reported in the scientific literature. Although current classifications do not consider ORS as a unique clinical entity, its existence is widely acknowledged. Different approaches to treatment have been described.
1) Portray the clinical features and treatment response of a patient with ORS. 2) Summarize knowledge on different treatment options for ORS.
We present the case of a teenager with major depressive disorder who developed the delusional belief of emitting a foul smell (without any other psychotic symptoms), and report his response to antidepressants and cognitive-behavioral therapy. Subsequently, we embark on a literature review on pharmacological and non-pharmacological options for patients with ORS.
We conducted a literature review in different databases using the keyword 'olfactory reference syndrome'. Papers published from 1971 to 2014 were selected on the basis of availability, relevant information in the title/abstract, and language (English, Spanish or Portuguese).
A brief summary is presented on the treatment options found in selected papers.
Different treatment approaches have proven beneficial for patients with ORS. This may reflect, however, a diversity of mechanisms by which this ailment is generated. More research on the physiopathology of ORS might result in better treatment outcomes.
In the last few decades, the discovery of large ditched enclosures in Iberia has revealed the diversity and complexity of deposition and manipulation of human bone remains. Alongside traditional ritual burials (mainly megalithic tombs and hypogea), fragmented and scattered human bones mixed with other kinds of material culture began to appear in many features. This is the case for Ditch 5 at Marroquíes, which offers an excellent opportunity to explore this ritual behaviour. Based on a multi-proxy approach, three main conclusions can be drawn: 1) the skeletal elements present show deliberate selection of particular categories of bones; 2) depositional episodes included the remains of people who died at different points in time and were subject to different taphonomic processes, and 3) mobility patterns indicate that all individuals, with one possible exception, were local. The movement and manipulations of body parts may reflect the active role of people after death as social and symbolic elements that retain agency and capacity for action.
Predicting breed-specific environmental suitability has been problematic in livestock production. Native breeds have low productivity but are thought to be more robust to perform under local conditions than exotic breeds. Attempts to introduce genetically improved exotic breeds are generally unsuccessful, mainly due to the antagonistic environmental conditions. Knowledge of the environmental conditions that are shaping the breed would be needed to determine its suitability to different locations. Here, we present a methodology to predict the suitability of breeds for different agro-ecological zones using Geographic Information Systems tools and predictive habitat distribution models. This methodology was tested on the current distribution of two introduced chicken breeds in Ethiopia: the Koekoek, originally from South Africa, and the Fayoumi, originally from Egypt. Cross-validation results show this methodology to be effective in predicting breed suitability for specific environmental conditions. Furthermore, the model predicts suitable areas of the country where the breeds could be introduced. The specific climatic parameters that explained the potential distribution of each of the breeds were similar to the environment from which the breeds originated. This novel methodology finds application in livestock programs, allowing for a more informed decision when designing breeding programs and introduction programs, and increases our understanding of the role of the environment in livestock productivity.
Early, conforming antibiotic treatment in elderly patients hospitalised for community-acquired pneumonia (CAP) is a key factor in the prognosis and mortality. The objective was to examine whether empirical antibiotic treatment was conforming according to the Spanish Society of Pulmonology and Thoracic Surgery guidelines in these patients. Multicentre study in patients aged ⩾65 years hospitalised due to CAP in the 2013–14 and 2014–15 influenza seasons. We collected socio-demographic information, comorbidities, influenza/pneumococcal vaccination history and antibiotics administered using a questionnaire and medical records. Bivariate analyses and multilevel logistic regression were made. In total, 1857 hospitalised patients were included, 82 of whom required intensive care unit (ICU) admission. Treatment was conforming in 51.4% (95% confidence interval (CI) 49.1–53.8%) of patients without ICU admission and was associated with absence of renal failure without haemodialysis (odds ratio (OR) 1.49, 95% CI 1.15–1.95) and no cognitive dysfunction (OR 1.71, 95% CI 1.25–2.35), when the effect of the autonomous community was controlled for. In patients with ICU admission, treatment was conforming in 45.1% (95% CI 34.1–56.1%) of patients and was associated with the hospital visits in the last year (<3 vs. ⩾3, OR 2.70, 95% CI 1.03–7.12) and there was some evidence that this was associated with season. Although the reference guidelines are national, wide variability between autonomous communities was found. In patients hospitalised due to CAP, health services should guarantee the administration of antibiotics in a consensual manner that is conforming according to clinical practice guidelines.
Attention-deficit/hyperactivity disorder (ADHD) is characterized by problems in regulating attention and in suppressing disruptive motor activity, i.e. hyperactivity and impulsivity. We recently found evidence that aberrant distribution of posterior α band oscillations (8–12 Hz) is associated with attentional problems in ADHD. The sensorimotor cortex also produces strong 8–12 Hz band oscillations, namely the μ rhythm, and is thought to have a similar inhibitory function. Here, we now investigate whether problems in distributing α band oscillations in ADHD generalize to the μ rhythm in the sensorimotor domain.
In a group of adult ADHD (n = 17) and healthy control subjects (n = 18; aged 21–40 years) oscillatory brain activity was recorded using magnetoencephalography during a visuo-spatial attention task. Subjects had to anticipate a target with unpredictable timing and respond by pressing a button.
Preparing a motor response, the ADHD group failed to increase hemispheric μ lateralization with relatively higher μ power in sensorimotor regions not engaged in the task, as the controls did (F1,33 = 8.70, p = 0.006). Moreover, the ADHD group pre-response μ lateralization not only correlated positively with accuracy (rs = 0.64, p = 0.0052) and negatively with intra-individual reaction time variability (rs = −0.52, p = 0.033), but it also correlated negatively with the score on an ADHD rating scale (rs = −0.53, p = 0.028).
We suggest that ADHD is associated with an inability to sufficiently inhibit task-irrelevant sensorimotor areas by means of modulating μ oscillatory activity. This could explain disruptive motor activity in ADHD. These results provide further evidence that impaired modulation of α band oscillations is involved in the pathogenesis of ADHD.
The perspective of statistical state dynamics (SSD) has recently been applied to the study of mechanisms underlying turbulence in a variety of physical systems. An SSD is a dynamical system that evolves a representation of the statistical state of the system. An example of an SSD is the second-order cumulant closure referred to as stochastic structural stability theory (S3T), which has provided insight into the dynamics of wall turbulence, and specifically the emergence and maintenance of the roll/streak structure. S3T comprises a coupled set of equations for the streamwise mean and perturbation covariance, in which nonlinear interactions among the perturbations has been removed, restricting nonlinearity in the dynamics to that of the mean equation and the interaction between the mean and perturbation covariance. In this work, this quasi-linear restriction of the dynamics is used to study the structure and dynamics of turbulence in plane Poiseuille flow at moderately high Reynolds numbers in a closely related dynamical system, referred to as the restricted nonlinear (RNL) system. Simulations using this RNL system reveal that the essential features of wall-turbulence dynamics are retained. Consistent with previous analyses based on the S3T version of SSD, the RNL system spontaneously limits the support of its turbulence to a small set of streamwise Fourier components, giving rise to a naturally minimal representation of its turbulence dynamics. Although greatly simplified, this RNL turbulence exhibits natural-looking structures and statistics, albeit with quantitative differences from those in direct numerical simulations (DNS) of the full equations. Surprisingly, even when further truncation of the perturbation support to a single streamwise component is imposed, the RNL system continues to self-sustain turbulence with qualitatively realistic structure and dynamic properties. RNL turbulence at the Reynolds numbers studied is dominated by the roll/streak structure in the buffer layer and similar very large-scale structure (VLSM) in the outer layer. In this work, diagnostics of the structure, spectrum and energetics of RNL and DNS turbulence are used to demonstrate that the roll/streak dynamics supporting the turbulence in the buffer and logarithmic layer is essentially similar in RNL and DNS.
The invariants of the velocity gradient tensor,
, and their enstrophy and strain components are studied in the logarithmic layer of an incompressible turbulent channel flow. The velocities are filtered in the three spatial directions and the results are analysed at different scales. We show that the
plane does not capture the changes undergone by the flow as the filter width increases, and that the enstrophy/enstrophy-production and strain/strain-production planes represent better choices. We also show that the conditional mean trajectories may differ significantly from the instantaneous behaviour of the flow since they are the result of an averaging process where the mean is 3–5 times smaller than the corresponding standard deviation. The orbital periods in the
plane are shown to be independent of the intensity of the events, and of the same order of magnitude as those in the enstrophy/enstrophy-production and strain/strain-production planes. Our final goal is to test whether the dynamics of the flow is self-similar in the inertial range, and the answer turns out to be that it is not. The mean shear is found to be responsible for the absence of self-similarity and progressively controls the dynamics of the eddies observed as the filter width increases. However, a self-similar behaviour emerges when the calculations are repeated for the fluctuating velocity gradient tensor. Finally, the turbulent cascade in terms of vortex stretching is considered by computing the alignment of the vorticity at a given scale with the strain at a different one. These results generally support a non-negligible role of the phenomenological energy-cascade model formulated in terms of vortex stretching.
The new generation of energy-dispersive X-ray (EDX) detectors with higher count rates than ever before, paves the way for a new approach to quantitative elemental analysis in the scanning transmission electron microscope. Here we demonstrate a method of calculating partial cross sections for use in quantifying EDX data, beneficial especially because of the simplicity of its implementation. Applying this approach to acid-leached PtCo catalyst nanoparticles leads to quantitative determination of the Pt surface enrichment.
The dietary inflammatory index (DII) is a new tool to assess the inflammatory potential of the diet. In the present study, we aimed to determine the association between the DII and BMI, waist circumference and waist:height ratio (WHtR). We conducted a cross-sectional study of 7236 participants recruited into the PREvención con DIeta MEDiterránea trial. Information from a validated 137-item FFQ was used to calculate energy, food and nutrient intakes. A fourteen-item dietary screener was used to assess adherence to the Mediterranean diet (MeDiet). Sex-specific multivariable linear regression models were fitted to estimate differences (and 95 % CI) in BMI, waist circumference and WHtR across the quintiles of the DII. All nutrient intakes, healthy foods and adherence to the MeDiet were higher in the quintile with the lowest DII score (more anti-inflammatory values) except for intakes of animal protein, saturated fat and monounsaturated fat. Although an inverse association between the DII and total energy was apparent, the DII was associated with higher average BMI, waist circumference and WHtR after adjusting for known risk factors. The adjusted difference in the WHtR for women and men between the highest and lowest quintiles of the DII was 1·60 % (95 % CI 0·87, 2·33) and 1·04 % (95 % CI 0·35, 1·74), respectively. Pro-inflammatory scores remained associated with obesity after controlling for the effect that adherence to a MeDiet had on inflammation. In conclusion, the present study shows a direct association between the DII and indices of obesity, and supports the hypothesis that diet may have a role in the development of obesity through inflammatory modulation mechanisms.