Mixing of a passive scalar in isotropic and sheared homogeneous turbulence

In order to calculate the velocity and scalar fields, the three dimensional, time-dependent equations of motion and the diffusion equation were solved numerically. The following cases were treated: isotropic, homogeneous turbulence with decay of a passive scalar; and homogeneous turbulent shear flow with a passive scalar whose mean varies linearly in the spanwise direction. The solutions were obtained at relatively low Reynolds numbers so that all of the turbulent scales could be resolved without modeling. Turbulent statistics such as integral length scales, Taylor microscales, Kolmogorov length scale, one- and two-point correlations of velocity-velocity and velocity-scalar, turbulent Prandtl/Schmidt number, r.m.s. values of velocities, the scalar quantity and pressure, skewness, decay rates, and decay exponents were calculated. The results are compared with the available expermental results, and good agreement is obtained

Conducting Qualitative Longitudinal Research: Fieldwork Experiences

This collection draws on the fieldwork experiences of some of the researchers involved in the ESRC 'Timescapes: Changing Relationships and Identities throughthe Life Course‘ programme. Timescapes, the first major Qualitative Longitudinal (QLL) study to be funded in the UK, aims to build a picture of life in 21st century Britain by gathering, archiving and analysing interviews from over 400 people living in a variety of circumstances across the UK. Temporal understanding is central to the programme. In essence, Timescapes is concerned with the intersection between different dimensions of time and the ways in which temporality shapes and is shaped by the changing relationships and identities of different individuals and collectives. We are exploring how individuals perceive past, present and future, and the relationship between their biographies and wider historical processes. Our work is framed by Barbara Adam‘s (1998) notion of 'timescapes‘. Like a landscape, cityscape or seascape a timescape is a panorama or view of the world in which time is placed as central

Aortic dissection type I in a weightlifter with hypertension: A case report

Acute aortic dissection can occur at the time of intense physical exertion in strength-trained athletes like weightlifters, bodybuilders, throwers, and wrestlers

Direct acetylation of sunflower oil in the presence of boron trioxide catalyst and the adduct usage as the base stock and lubricant additive

Lubrication properties of sunflower oil have been modified by epoxidation in the first step and acetylation of the obtained epoxide in the second step. Epoxidation has been followed in dichloromethane solution in the presence of hydrogen peroxide and acetic acid as oxidizing agent and sulfuric acid as catalyst. The reaction has been monitored and optimized by measurement of iodine value, epoxy content, and recording the FTIR spectrum at different experimental conditions. Acetylation has been performed by enduring the optimized conditions of epoxidation reaction, in the presence of boron trioxide as catalyst and at elevated temperature. The recent reaction has been monitored and optimized by measurement of hydroxyl value, epoxy content, and recording the FTIR spectrum at different experimental conditions. The final product of both,epoxidation and acetylation reactions has been confirmed by FTIR and NMR data. Relative to sunflower oil, pour point and oxidation stability of the modified oil has considerably been improved. The modified oil has successfully been employed in the formulation of industrial gear oil. The investigation on the possibility of the additive application of the modified oil, as well as its miscibility with additives was considered

Unusual presentation of thyrotoxicosis as complete heart block and renal failure: a case report

<p>Abstract</p> <p>Introduction</p> <p>Thyrotoxicosis is a clinical entity often very difficult to diagnose without biochemical confirmation as its clinical features can be highly varied. The most common cardiac manifestations of thyrotoxicosis are resting sinus tachycardia, supraventricular tachycardia including atrial fibrillation and atrial flutter with or without cardiac failure. Bradycardia and atrio-ventricular conduction defects are very uncommon in thyrotoxicosis.</p> <p>Case presentation</p> <p>We report the case of a 59-year-old Caucasian man presenting with progressive weight loss, abnormal liver function, acute renal failure and complete heart block due to thyrotoxicosis.</p> <p>Conclusion</p> <p>Thyrotoxicosis should be considered as a possible diagnosis in patients with bradycardia and heart blocks associated with abnormal symptoms like weight loss. Nevertheless, the clinical, electrophysiological and biochemical abnormalities associated with thyrotoxicosis may be completely reversible restoring euthyroid state.</p

Do interictal epileptiform discharges and brain responses to electrical stimulation come from the same location? An advanced source localization solution

Identification of seizure sources in the brain is of paramount importance, particularly for drug-resistant epilepsy patients who may require surgical operation. Interictal epileptiform discharges (IEDs), which may or may not be frequent, are known to originate from seizure networks. Delayed responses (DRs) to brain electrical stimulation have been recently discovered. If DRs and IEDs come from the same location and the DRs can be accurately localized, there will be a significant step in identification of the seizure sources. The solution to this important question has been investigated in this paper. For this, we have exploited the morphology of these spike-type events, as well as the variability in their temporal locations, to develop new constraints for an adaptive Bayesian beamformer that outperforms the conventional and recently proposed beamformers even for identifying correlated sources. This beamformer is applied to an array (a.k.a mat) of cortical EEG electrodes. The developed approach has been tested on 300 data segments from five epileptic patients included in this study, which clinically represent a large population of candidates for surgical treatment. As the significant outcome of applying this beamformer, it is very likely (if not certain) that for an epileptic subject, the IEDs and DRs originate from the same location in the brain. This paves the way for a quick identification of the source(s) of seizure in the brain

Whole‐brain microscopy reveals distinct temporal and spatial efficacy of anti‐Aβ therapies

Many efforts targeting amyloid-β (Aβ) plaques for the treatment of Alzheimer's Disease thus far have resulted in failures during clinical trials. Regional and temporal heterogeneity of efficacy and dependence on plaque maturity may have contributed to these disappointing outcomes. In this study, we mapped the regional and temporal specificity of various anti-Aβ treatments through high-resolution light-sheet imaging of electrophoretically cleared brains. We assessed the effect on amyloid plaque formation and growth in Thy1-APP/PS1 mice subjected to β-secretase inhibitors, polythiophenes, or anti-Aβ antibodies. Each treatment showed unique spatiotemporal Aβ clearance, with polythiophenes emerging as a potent anti-Aβ compound. Furthermore, aligning with a spatial-transcriptomic atlas revealed transcripts that correlate with the efficacy of each Aβ therapy. As observed in this study, there is a striking dependence of specific treatments on the location and maturity of Aβ plaques. This may also contribute to the clinical trial failures of Aβ-therapies, suggesting that combinatorial regimens may be significantly more effective in clearing amyloid deposition. Keywords: Alzheimer's disease; amyloid-beta; brain; light-sheet microscopy; tissue clearin