Medial prefrontal cortex and anterior cingulate cortex in the generation of alpha activity induced by transcendental meditation: a magnetoencephalographic study.

Previous EEG studies have shown that transcendental meditation (TM) increases frontal and central alpha activity. The present study was aimed at identifying the source of this alpha activity using magnetoencephalography (MEG) and electroencephalography (EEG) simultaneously on eight TM practitioners before, during, and after TM. The magnetic field potentials corresponding to TM-induced alpha activities on EEG recordings were extracted, and we attempted to localize the dipole sources using the multiple signal classification (MUSIC) algorithm, equivalent current dipole source analysis, and the multiple spatio-temporal dipole model. Since the dipoles were mapped to both the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC), it is suggested that the mPFC and ACC play an important role in brain activity induced by TM.</p

Diagnostic value of ventilation/perfusion single-photon emission computed tomography/computed tomography for bronchiolitis obliterans syndrome in patients after lung transplantation

OBJECTIVE: To evaluate the diagnostic value of function volume/morphological volume ratio calculated from ventilation/perfusion single-photon emission computed tomography/computed tomography in distinguishing the lungs with bronchiolitis obliterans syndrome (BOS) from the lungs without this syndrome after lung transplantation and to assess its relationship with spirometry parameters. MATERIALS AND METHODS: We retrospectively identified 84 consecutive lung transplant recipients and 13 donors who underwent ventilation/perfusion single-photon emission computed tomography/computed tomography. Differences in the function volume/morphological volume ratio of unilateral lungs were tested for significance between the lungs with and without BOS. Receiver operating characteristics and correlations between function volume/morphological volume ratios of bilateral lungs and forced expiratory volume in 1 s, forced vital capacity, and total lung capacity were analyzed. RESULTS: The function volume/morphological volume ratios of ventilation and perfusion images of unilateral lungs were significantly lower in lungs with BOS (each P CONCLUSION: The function volume/morphological volume ratio enables a semiquantitative assessment of ventilation and perfusion lung functions and is useful for diagnosing BOS after lung transplantation

Aerodynamic Pitching Stability Of Sedan-Type Vehicles Influenced By Pillar-Shape Configurations

The present study investigated the aerodynamic pitching stability of sedan-type vehicles under the influence of A- and C-pillar geometrical configurations. The numerical method used for the investigation is based on the Large Eddy Simulation (LES) method. Whilst, the Arbitrary Lagrangian-Eulerian (ALE) method was employed to realize the prescribed pitching oscillation of vehicles during dynamic pitching and fluid flow coupled simulations. The trailing vortices that shed from the A-pillar and C-pillar edges produced the opposite tendencies on how they affect the aerodynamic pitching stability of vehicles. In particular, the vortex shed from the A-pillar edge tended to enhance the pitching oscillation of vehicle, while the vortex shed from the C-pillar edge tended to suppress it. Hence, the vehicle with rounded A-pillar and angular C-pillar exhibited a higher aerodynamic damping than the vehicle with the opposite A- and C-pillars configurations. The underlying aerodynamic damping mechanism has been verified through flow visualization of phase-averaged results

Effects Of Transient Aerodynamics On Vehicle Stability: A Large Eddy Simulation Analysis

The present study investigated the extent to which the results obtained from simple bluff body model, regarding pitching stability, can be applied to real vehicle aerodynamics. The investigation was carried out using a large eddy simulation method with vehicle-motion-airflow dynamic coupling capability. The aerodynamic damping coefficient and mechanism obtained from realistic sedan-type vehicle model cases are found similar to the one for simple body model cases. These agreements deduce that the use of simple body model in automotive aerodynamic research is justifiable

On The Aerodynamic Damping Mechanism Of Vehicle Pitching Stability Using Large Eddy Simulation

Large eddy simulation was conducted to investigate the pitching stability characteristic of notchback-type vehicle. In this paper, two simplified vehicle models represent the notchback of different pitching stability characteristics were used. Numerical method adopted was validated by comparing the simulation result with wind tunnel data. To probe the dynamic response of the models, forced-sinusoidal-pitching oscillation is imposed and the resulting pitch moment is phase averaged, and decomposed into the stationary, quasi-stationary, and dynamic components for assessment. Vehicle model of higher aerodynamic damping is found to exhibit two-dimensional flow structure above the central region of its trunk deck, whereas vehicle model of lower aerodynamic damping is associated with strong cross flow and upwash circulatory flow structure. The outcome of this work demonstrates how unsteady aerodynamics can be exploited for the control of vehicle’s straight ahead stability

Large Eddy Simulation Of Flow Past Road Vehicles Subjected To Pitching Oscillation

We examine the unsteady aerodynamic effect on pitching stability of road vehicle by large eddy simulation. To probe the vehicle's dynamic response, a forced-sinusoidal-pitching oscillation was imposed on the vehicles during the simulation. For validation purpose, we compare the numerical result with wind tunnel measurement. The simulation result shows the strong influence of unsteady flow structures around the rear end of the vehicles on their pitching stability. These flow structures include the front and rear pillar vortices and cross flow component above the trunk deck. The configuration of curved front pillar coupled with sharp-edged rear pillar produce a trend for the unsteady aerodynamic force to restrain the pitching motion, while the presence of front pillar vortices, which are associated with sharp-edge front pillar configuration, resulted in a tendency for enhancing the pitching motion

Seasonality in daily movement patterns of mandrills revealed by combining direct tracking and camera traps

野生マンドリルの移動パターンを解明 --直接追跡法と自動撮影カメラ法を組み合わせて説得力のある結論を得る--. 京都大学プレスリリース. 2021-11-26.Movement is a fundamental characteristic of animals, but challenging to measure noninvasively. Noninvasive methods for measuring travel have different weaknesses, so multiple techniques need to be applied multiple techniques for reliable inferences. We used two methods, direct tracking and camera trapping, to examine the variation in time and seasonal differences in movement rates of mandrills (Mandrillus sphinx), an elusive primate that lives in large groups in central Africa. In a 400-km2 rainforest area in Moukalaba-Doudou National Park, Gabon, we tracked unidentified groups 46 times from 2009 to 2013. We systematically placed 157 terrestrial camera traps in the same area from 2012 to 2014 and recorded groups 309 times. Generalized additive mixed models (GAMMs) of the tracking data indicated that the group travel speed varied with time and season. In the fruiting season, the movement rate fluctuated with time in a bimodal pattern, whereas in the nonfruiting season, it increased monotonously with time. The predicted day range was longer in the fruiting season (6.98 km) than in the nonfruiting season (6.06 km). These seasonal differences suggest responses to changes in food resources and temperature. Camera-trap detection rates showed similar temporal and seasonal patterns to the tracking data, allowing us to generalize our findings to the population level. Moreover, cameras never detected mandrills at night, and we observed that they slept high in trees and hardly moved until the next morning, all suggesting their strict avoidance of nighttime movement. This study demonstrated the significance of the multiple-method approach in drawing robust conclusions on temporal patterns of animal movement.Le mouvement est une caractéristique fondamentale des animaux, mais il est difficile de le mesurer de manière non invasive. Les méthodes non invasives de mesure des déplacements présentent des faiblesses différentes, de sorte que nous devons appliquer plusieurs techniques à un même sujet pour obtenir des déductions fiables. Nous avons utilisé deux méthodes, le suivi direct et le piégeage photographique, pour examiner les variations temporelles et la différence saisonnière des taux de déplacement des mandrills (Mandrillus sphinx), un primate insaisissable vivant en grands groupes. Dans une zone de forêt tropicale humide de 400 km2 du parc national de Moukalaba-Doudou au Gabon, nous avons suivi des groupes non identifiés 46 fois entre 2009 et 2013. Dans la même zone, nous avons systématiquement placé 157 pièges photographiques terrestres de 2012 à 2014 et enregistré des groupes 309 fois. Les modèles mixtes additifs généralisés (GAMM) des données de suivi ont indiqué que la vitesse de déplacement des groupes variait en fonction du temps et des saison. Pendant la saison de fructification, la vitesse de déplacement fluctuait dans le temps selon un schéma bimodal, tandis que pendant la saison de non-fructification, elle augmentait de façon monotone avec le temps. Les distances journalières prédites étaient plus longues pendant la saison de fructification (6, 98 km) que pendant la saison de non-fructification (6, 06 km). Ces différences saisonnières suggèrent des réponses aux changements de ressources alimentaires et de température. Les taux de détection des pièges photographiques ont montré des tendances temporelles et saisonnières similaires à celles des données de suivi, ce qui nous permet de généraliser nos conclusions au niveau de la population. De plus, les caméras n’ont jamais détecté les mandrills la nuit, et nous avons observé qu’ils dormaient haut dans les arbres et ne bougeaient pratiquement pas jusqu’au lendemain matin, ce qui suggère qu’ils évitent strictement de se déplacer la nuit. Cette étude a démontré l’importance de l’approche à méthodes multiples pour tirer des conclusions solides sur les modes temporels de déplacement des animaux

In Vitro Gene Delivery Mediated by Asialofetuin-Appended Cationic Liposomes Associated with γ-Cyclodextrin into Hepatocytes

The purpose of this study is to evaluate in vitro gene delivery mediated by asialofetuin-appended cationic liposomes (AF-liposomes) associating cyclodextrins (CyD/AF-liposomes) as a hepatocyte-selective nonviral vector. Of various CyDs, AF-liposomes associated with plasmid DNA (pDNA) and γ-cyclodextrin (γ-CyD) (pDNA/γ-CyD/AF-liposomes) showed the highest gene transfer activity in HepG2 cells without any significant cytotoxicity. In addition, γ-CyD enhanced the encapsulation ratio of pDNA with AF-liposomes, and also increased gene transfer activity as the entrapment ratio of pDNA into AF-liposomes was increased. γ-CyD stabilized the liposomal membrane of AF-liposomes and inhibited the release of calcein from AF-liposomes. The stabilizing effect of γ-CyD may be, at least in part, involved in the enhancing gene transfer activity of pDNA/γ-CyD/AF-liposomes. Therefore, these results suggest the potential use of γ-CyD for an enhancer of transfection efficiency of AF-liposomes