A two-length scale, second moment turbulence model (Reynolds averaged Navier-Stokes, RANS) is proposed to capture a wide variety of single-phase flows, spanning from incompressible flows with single ...fluids and mixtures of different density fluids (variable density flows) to flows over shock waves. The two-length scale model was developed to address an inconsistency present in the single-length scale models, e.g. the inability to match both variable density homogeneous Rayleigh-Taylor turbulence and Rayleigh-Taylor induced turbulence, as well as the inability to match both homogeneous shear and free shear flows. The two-length scale model focuses on separating the decay and transport length scales, as the two physical processes are generally different in inhomogeneous turbulence. This allows reasonable comparisons with statistics and spreading rates over such a wide range of turbulent flows using a common set of model coefficients. The specific canonical flows considered for calibrating the model include homogeneous shear, single-phase incompressible shear driven turbulence, variable density homogeneous Rayleigh-Taylor turbulence, Rayleigh-Taylor induced turbulence, and shocked isotropic turbulence. The second moment model shows to compare reasonably well with direct numerical simulations (DNS), experiments, and theory in most cases. The model was then applied to variable density shear layer and shock tube data and shows to be in reasonable agreement with DNS and experiments. The importance of using DNS to calibrate and assess RANS type turbulence models is also highlighted.
Olfactory neuropathy spectrum disorder is characterized by hyposmia or anosmia and hypoplastic or absent olfactory bulbs. There may be an association between olfactory neuropathy spectrum disorder ...and Wolff‐Parkinson‐White syndrome.
Olfactory neuropathy spectrum disorder is characterized by hyposmia or anosmia and hypoplastic or absent olfactory bulbs. There may be an association between olfactory neuropathy spectrum disorder and Wolff‐Parkinson‐White syndrome.
Vestibular symptoms are common after concussion. Vestibular Ocular Motor Screening identifies vestibular impairment, including postconcussive visual motion sensitivity, though the underlying ...functional brain alterations are not defined. We hypothesized that alterations in multisensory processing are responsible for postconcussive visual motion sensitivity, are detectable on fMRI, and correlate with symptom severity.
Twelve patients with subacute postconcussive visual motion sensitivity and 10 healthy control subjects underwent vestibular testing and a novel fMRI visual-vestibular paradigm including 30-second "neutral" or "provocative" videos. The presence of symptoms/intensity was rated immediately after each video. fMRI group-level analysis was performed for a "provocative-neutral" condition.
-statistic images were nonparametrically thresholded using clusters determined by
> 2.3 and a corrected cluster significance threshold of
= .05. Symptoms assessed on Vestibular Ocular Motor Screening were correlated with fMRI mean parameter estimates using Pearson correlation coefficients.
Subjects with postconcussive visual motion sensitivity had significantly more Vestibular Ocular Motor Screening abnormalities and increased symptoms while viewing provocative videos. While robust mean activation in the primary and secondary visual areas, the parietal lobe, parietoinsular vestibular cortex, and cingulate gyrus was seen in both groups, selective increased activation was seen in subjects with postconcussive visual motion sensitivity in the primary vestibular/adjacent cortex and inferior frontal gyrus, which are putative multisensory visual-vestibular processing centers. Moderate-to-strong correlations were found between Vestibular Ocular Motor Screening scores and fMRI activation in the left frontal eye field, left middle temporal visual area, and right posterior hippocampus.
Increased fMRI brain activation in visual-vestibular multisensory processing regions is selectively seen in patients with postconcussive visual motion sensitivity and is correlated with Vestibular Ocular Motor Screening symptom severity, suggesting that increased visual input weighting into the vestibular network may underlie postconcussive visual motion sensitivity.
To the author's knowledge, this is the first reported case in the literature of a supraseptal ethmoid sinus cell, located between the nasal septum and ethmoid roof. Such a cell, while rare, should be ...recognized and dissected carefully to prevent skull base injury and cerebrospinal fluid leak.
To the author's knowledge, this is the first reported case in the literature of a supraseptal ethmoid sinus cell, located between the nasal septum and ethmoid roof. Such a cell, while rare, should be recognized and dissected carefully to prevent skull base injury and cerebrospinal fluid leak.
Summary
Background
Children with severe, persistent atopic eczema (AE) have limited treatment options, often requiring systemic immunosuppression.
Objective
To evaluate the effect of the ...temperature‐controlled laminar airflow (TLA) treatment in children/adolescents with severe AE.
Methods
We recruited 15 children aged 2‐16 years with long‐standing, severe AE and sensitization to ≥1 perennial inhalant allergen. Run‐in period of 6‐10 weeks (3 visits) was followed by 12‐month treatment with overnight TLA (Airsonett®, Sweden). The primary outcome was eczema severity (SCORAD‐Index and Investigator Global Assessment‐IGA). Secondary outcomes included child/family dermatology quality of life and family impact questionnaires (CDQLI, FDQLI, DFI), patient‐oriented eczema measure (POEM), medication requirements and healthcare contacts. The study is registered as ISRCTN65865773.
Results
There was a significant reduction in AE severity ascertained by SCORAD and IGA during the 12‐month intervention period (P < .001). SCORAD was reduced from a median of 34.9 interquartile range 28.75‐45.15 at Baseline to 17.2 12.95‐32.3 at the final visit, and IGA improved significantly from 4 3‐4 to 2 1‐3. We observed a significant improvement in FDQLI (16.0 12.25‐19.0 to 12 8‐18, P = .023) and DFI (P = .011), but not CDQLI or POEM. Compared to 6‐month period prior to enrolment, there was a significant reduction at six months after the start of the intervention in potent topical corticosteroids (P = .033). The exploratory cluster analysis revealed two strongly divergent patterns of response, with 9 patients classified as responders, and 6 as non‐responders.
Conclusion and Clinical Relevance
Addition of TLA device to standard pharmacological treatment may be an effective add‐on to the management of difficult‐to‐control AE.
Objective: To examine crash rates over time among 16–17-year-old drivers compared to older drivers. Methods: Data were from a random sample of 854 of the 3,500 study participants in SHRP 2, a U.S. ...national, naturalistic driving (instrumented vehicle) study. Crashes/10,000 miles by driver age group, 3-month period, and sex were examined within generalized linear mixed models. Results: Analyses of individual differences between age cohorts indicated higher incidence rates in the 16–17-year old cohort relative to older age groups each of the first four quarters (except the first quarter compared to 18–20 year old drivers) with incident rate ratios (IRR) ranging from 1.98 to 18.90, and for the full study period compared with drivers 18–20 (IRR = 1.69, CI = 1.00, 2.86), 21 to 25 (IRR = 2.27, CI = 1.31, 3.91), and 35 to 55 (IRR = 4.00, CI = 2.28, 7.03). Within the 16–17-year old cohort no differences were found in rates among males and females and the decline in rates over the 24-month study period was not significant. Conclusions: The prolonged period of elevated crash rates suggests the need to enhance novice young driver prevention approaches such as Graduated Driver’s Licensing limits, parent restrictions, and post-licensure supervision and monitoring. Practical Applications: Increases are needed in Graduated Driver’s Licensing limits, parent restrictions, and postlicensure supervision and monitoring.
Severe, recurrent or bilateral optic neuritis (ON) often falls within the neuromyelitis optica spectrum disorders (NMOSD), but the diagnosis can be particularly challenging and has important ...treatment implications. We report the features, course and outcomes of patients presenting with atypical ON when isolated at onset. We retrospectively analyzed 69 sequential patients referred to a single UK NMO center with isolated ON at onset. Aquaporin-4 antibody (AQP4-Ab) assessment was performed in all patients and IgG1 myelin-oligodenrocyte glycoprotein (MOG-Ab) in AQP4-Ab
neg
patients. 37 AQP4-Ab positive (AQP4-Ab
pos
) and 32 AQP4-Ab negative (AQP4-Ab
neg
) patients (8 with MOG-Ab) were identified. The AQP4-Ab
neg
group included heterogeneous diagnoses: multiple sclerosis (MS), NMO, relapsing isolated ON (RION), monophasic isolated ON and relapsing acute disseminated encephalomyelitis (ADEM)-like syndromes. Compared to AQP4-Ab
neg
patients, AQP4-Ab
pos
patients had a worse residual visual outcome from first attack (median VFSS 4 vs. 0,
p
= 0.010) and at last assessment (median VFSS 5 versus 2,
p
= 0.005). However, AQP4-Ab
neg
patients with RION also had poor visual outcome. Up to 35 % of AQP4-Ab
neg
patients developed a LETM and two developed low positivity for AQP4-Ab over time. Eight AQP4-Ab
neg
patients (25 %) were MOG-Ab positive, covering a range of phenotypes excluding MS; the first ON attack was often bilateral and most had relapsing disease with a poor final visual outcome VFSS 4, range (0–6). In conlcusion, AQP4-Ab positivity is confirmed as a predictor of poor visual outcome but AQP4-Ab
neg
RION also had a poor visual outcome. Of those without AQP4-Ab, 25 % had MOG-Ab and another 25 % developed MS; thus, MOG-Ab is associated with AQP4-Ab
neg
non-MS ON.
On 2019 April 5, while the Parker Solar Probe was at its 35 solar radius perihelion, the data set collected at 293 samples/s contained more than 10,000 examples of spiky electric-field-like ...structures with durations less than 200 milliseconds and amplitudes greater than 10 mV m−1. The vast majority of these events were caused by plasma turbulence. Defining dust events as those with similar, narrowly peaked, positive, and single-ended signatures resulted in finding 135 clear dust events, which, after correcting for the low detection efficiently, resulted in an estimate consistent with the 1000 dust events expected from other techniques. Defining time domain structures (TDS) as those with opposite polarity signals in the opposite antennas resulted in finding 238 clear TDS events which, after correcting for the detection efficiency, resulted in an estimated 500-1000 TDS events on this day. The TDS electric fields were bipolar, as expected for electron holes. Several events were found at times when the magnetic field was in the plane of the two measured components of the electric field such that the component of the electric field parallel to the magnetic field was measured. One example of significant parallel electric fields shows the negative potential that classified them as electron holes. Because the TDS observation rate was not uniform with time, it is likely that there were local regions below the spacecraft with field-aligned currents that generated the TDS.
Objectives
Mass administration of azithromycin has reduced mortality in children in sub‐Saharan Africa but its mode of action is not well characterised. A recent trial found that azithromycin given ...alongside seasonal malaria chemoprevention was not associated with a reduction in mortality or hospital admissions in young children. We investigated the effect of azithromycin on the nutritional status of children enrolled in this study.
Methods
A total of 19 578 children in Burkina Faso and Mali were randomised to receive either azithromycin or placebo alongside seasonal malaria chemoprevention with sulfadoxine–pyrimethamine plus amodiaquine monthly for three malaria transmission seasons (2014–2016). After each transmission season, anthropometric measurements were collected from approximately 4000 randomly selected children (2000 per country) at a cross‐sectional survey and used to derive nutritional status indicators. Binary and continuous outcomes between treatment arms were compared by Poisson and linear regression.
Results
Nutritional status among children was poor in both countries with evidence of acute and chronic malnutrition (24.9–33.3% stunted, 15.8–32.0% underweight, 7.2–26.4% wasted). There was a suggestion of improvement in nutritional status in Burkina Faso and deterioration in Mali over the study period. At the end of each malaria transmission season, nutritional status of children did not differ between treatment arms (seasonal malaria chemoprevention plus azithromycin or placebo) in either the intention‐to‐treat or per‐protocol analyses (only children with at least three cycles of SMC in the current intervention year).
Conclusions
The addition of azithromycin to seasonal malaria chemoprevention did not result in an improvement of nutritional outcomes in children in Burkina Faso and Mali.
Objectifs
L'administration massive d'azithromycine a réduit la mortalité infantile en Afrique subsaharienne mais son mode d'action n'est pas bien caractérisé. Un essai récent a révélé que l'azithromycine administrée parallèlement à la chimioprévention du paludisme saisonnier n'était pas associée à une réduction de la mortalité ou des hospitalisations chez les jeunes enfants. Nous avons étudié l'effet de l'azithromycine sur l'état nutritionnel des enfants inscrits à cette étude.
Méthodes19.578 enfants au Burkina Faso et au Mali ont été randomisés pour recevoir soit de l'azithromycine soit un placebo parallèlement à une chimioprévention du paludisme saisonnier avec du sulfadoxine‐pyriméthamine plus de l’amodiaquine par mois pendant trois saisons de transmission du paludisme (2014‐2016). Après chaque saison de transmission, des mesures anthropométriques ont été recueillies auprès d'environ 4.000 enfants sélectionnés au hasard (2.000 par pays) lors d'une enquête transversale et utilisées pour dériver des indicateurs de l'état nutritionnel. Les résultats binaires et continus entre les bras de traitement ont été comparés par la régression linéaire et de Poisson.
RésultatsL'état nutritionnel des enfants était médiocre dans les deux pays avec des signes de malnutrition aiguë et chronique (24,9 à 33,3% de retard de croissance, 15,8 à 32,0% d'insuffisance pondérale, 7,2 à 26,4% d'émaciation). Il a été suggéré une amélioration de l'état nutritionnel au Burkina Faso et une détérioration au Mali au cours de la période d'étude. A la fin de chaque saison de transmission du paludisme, l'état nutritionnel des enfants ne différait pas entre les bras de traitement (chimioprévention contre le paludisme saisonnier plus azithromycine ou placebo) dans les analyses en intention de traiter ou selon le protocole (seulement les enfants avec au moins trois cycles de chimioprévention dans l’année d’intervention en cours).
ConclusionsL'ajout d'azithromycine à la chimioprévention du paludisme saisonnier n'a pas entraîné d'amélioration des résultats nutritionnels chez les enfants au Burkina Faso et au Mali.
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