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Kaempferol Treatment after Traumatic Brain Injury during Early Development Mitigates Brain Parenchymal Microstructure and Neural Functional Connectivity Deterioration at Adolescence.
Targeting mitochondrial ion homeostasis using Kaempferol, a mitochondrial Ca2+ uniporter channel activator, improves energy metabolism and behavior soon after a traumatic brain injury (TBI) in developing rats. Because of broad TBI pathophysiology and brain mitochondrial heterogeneity, Kaempferol-mediated early-stage behavioral and brain metabolic benefits may accrue from diverse sources within the brain. We hypothesized that Kaempferol influences TBI outcome by differentially impacting the neural, vascular, and synaptic/axonal compartments. After TBI at early development (P31), functional magnetic resonance imaging and diffusion tensor imaging (DTI) were applied to determine imaging outcomes at adolescence (2 months post-injury). Vehicle and Kaempferol treatments were made at 1, 24, and 48 h post-TBI, and their effects were assessed at adolescence. A significant increase in neural connectivity was observed after Kaempferol treatment as assessed by the spatial extent and strength of the somatosensory cortical and hippocampal resting-state functional connectivity (RSFC) networks. However, no significant RSFC changes were observed in the thalamus. DTI measures of fractional anisotropy (FA) and apparent diffusion coefficient, representing synaptic/axonal and microstructural integrity, showed significant improvements after Kaempferol treatment, with highest changes in the frontal and parietal cortices and hippocampus. Kaempferol treatment also increased corpus callosal FA, indicating measurable improvement in the interhemispheric structural connectivity. TBI prognosis was significantly altered at adolescence by early Kaempferol treatment, with improved neural connectivity, neurovascular coupling, and parenchymal microstructure in select brain regions. However, Kaempferol failed to improve vasomotive function across the whole brain, as measured by cerebrovascular reactivity. The differential effects of Kaempferol treatment on various brain functional compartments support diverse cellular-level mitochondrial functional outcomes in vivo
The effect of temperature anisotropy on observations of Doppler dimming and pumping in the inner corona
Recent observations of the spectral line profiles and intensity ratio of the
O VI 1032 {\AA} and 1037.6 {\AA} doublet by the Ultraviolet Coronagraph
Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO), made in
coronal holes below 3.5 , provide evidence for Doppler dimming of the O VI
1037.6 {\AA} line and pumping by the chromospheric C II 1037.0182 {\AA} line.
Evidence for a significant kinetic temperature anisotropy of O ions was
also derived from these observations. We show in this Letter how the component
of the kinetic temperature in the direction perpendicular to the magnetic
field, for both isotropic and anisotropic temperature distributions, affects
both the amount of Doppler dimming and pumping. Taking this component into
account, we further show that the observation that the O VI doublet intensity
ratio is less than unity can be accounted for only if pumping by C II 1036.3367
{\AA} in addition to C II 1037.0182 {\AA} is in effect. The inclusion of the C
II 1036.3367 {\AA} pumping implies that the speed of the O ions can
reach 400 km/s around 3 which is significantly higher than the reported
UVCS values for atomic hydrogen in polar coronal holes. These results imply
that oxygen ions flow much faster than protons at that heliocentric distance.Comment: 9 pages, 3 figure
Modelling human factors in perceptual multimedia quality: On the role of personality and culture
Perception of multimedia quality is shaped by a rich interplay between system, context, and human factors. While system and context factors are widely researched, few studies in this area consider human factors as sources of systematic variance. This paper presents an analysis on the influence of personality (Five-Factor Model) and cultural traits (Hofstede Model) on the perception of multimedia quality. A set of 144 video sequences (from 12 short movie excerpts) were rated by 114 participants from a cross-cultural population, producing 1232 ratings. On this data, three models are compared: a baseline model that only considers system factors; an extended model that includes personality and culture as human factors; and an optimistic model in which each participant is modeled as a random effect. An analysis shows that personality and cultural traits represent 9.3% of the variance attributable to human factors while human factors overall predict an equal or higher proportion of variance compared to system factors. In addition, the quality-enjoyment correlation varied across the movie excerpts. This suggests that human factors play an important role in perceptual multimedia quality, but further research to explore moderation effects and a broader range of human factors is warranted
Accurate estimation of fish length in single camera photogrammetry with a fiducial marker
Videogrammetry and photogrammetry are increasingly being used in marine science for unsupervised data collection. The camera systems employed are complex, in contrast to "consumer"digital cameras and smartphones carried by potential citizen scientists. However, using consumer cameras in photogrammetry will introduce unknown length estimation errors through both the image acquisition process and lens distortion. This study presents a methodology to achieve accurate 2-dimensional (2-D) total length (TL) estimates of fish without specialist equipment or proprietary software. Photographs of fish were captured with an action camera using a background fiducial marker, a foreground fiducial marker and a laser marker. The geometric properties of the lens were modelled with OpenCV to correct image distortion. TL estimates were corrected for parallax effects using an algorithm requiring only the initial length estimate and known fish morphometric relationships. Correcting image distortion decreased RMSE by 96% and the percentage mean bias error (%MBE) by 50%. Correcting for parallax effects achieved a %MBE of -0.6%. This study demonstrates that the morphometric measurement of different species can be accurately estimated without the need for complex camera equipment, making it particularly suitable for deployment in citizen science and other volunteer-based data collection endeavours
Using Machine Vision to Estimate Fish Length from Images using Regional Convolutional Neural Networks
An image can encode date, time, location and camera information as metadata and implicitly encodes species information and data on human activity, for example the size distribution of fish removals. Accurate length estimates can be made from images using a fiducial marker; however, their manual extraction is time-consuming and estimates are inaccurate without control over the imaging system. This article presents a methodology which uses machine vision to estimate the total length (TL) of a fusiform fish (European sea bass). Three regional convolutional neural networks (R-CNN) were trained from public images. Images of European sea bass were captured with a fiducial marker with three non-specialist cameras. Images were undistorted using the intrinsic lens properties calculated for the camera in OpenCV; then TL was estimated using machine vision (MV) to detect both marker and subject. MV performance was evaluated for the three R-CNNs under downsampling and rotation of the captured images. Each R-CNN accurately predicted the location of fish in test images (mean intersection over union, 93%) and estimates of TL were accurate, with percent mean bias error (%MBE [95% CIs]) = 2.2% [2.0, 2.4]). Detections were robust to horizontal flipping and downsampling. TL estimates at absolute image rotations >20° became increasingly inaccurate but %MBE [95% CIs] was reduced to −0.1% [−0.2, 0.1] using machine learning to remove outliers and model bias. Machine vision can classify and derive measurements of species from images without specialist equipment. It is anticipated that ecological researchers and managers will make increasing use of MV where image data are collected (e.g. in remote electronic monitoring, virtual observations, wildlife surveys and morphometrics) and MV will be of particular utility where large volumes of image data are gathered
Estimates of the New Keynesian Phillips Curve for Pakistan
This paper presents estimates of the New Keynesian Phillips Curve (NKPC) for the agriculture, manufacturing and services sectors of Pakistan’s economy. The real marginal cost—derived from dynamic translog cost function—labour share of income and output gap are the indicators of economic activity along with past and expected inflation to determine inflation dynamics in each sector. The estimates of the structural parameters of the NKPC are consistent with economic theory in most of the models. Within-sample forecast performance and diagnostic tests indicate that the derived measure of real marginal cost performs better relative to the specifications with labour share of income or output gap. Further, the NKPC based on restrictive Cobb–Douglas production technology with labour input only does not perform better than the models that considers more inputs and intermediate cost. Our results show that the manufacturing is forward-looking sector followed by services and agriculture sectors.http://link.springer.com/journal/1812021-03-16hj2020Economic
The Behavior and Determinants of the Currency Deposit Ratio in Pakistan
The objective of this note was to investigate the factors behind significant increase in currency deposits ratio since FY09. Before investigating the factors, the note attempts to explain the balance sheet mechanism of withdrawal of currency from the banking system and the economic costs of increase in currency in circulation. In perspective of economic costs, the negative relationship between currency and total private sector deposits confirms that an increase in currency depletes deposits, which in turn hurts economic growth by restricting supply of loanable funds with the banks. From a theoretical standpoint, when we attempt to investigate determinants of currency deposits ratio through graphical analysis, inflation, government budgetary borrowing, industrial production index, investment in National Saving Schemes, remittances inflow, and wheat procurement are found to be the prominent factors behind increasing currency deposits ratio. The note also includes the econometric estimation of these factors
The Behavior and Determinants of the Currency Deposit Ratio in Pakistan
The objective of this note was to investigate the factors behind significant increase in currency deposits ratio since FY09. Before investigating the factors, the note attempts to explain the balance sheet mechanism of withdrawal of currency from the banking system and the economic costs of increase in currency in circulation. In perspective of economic costs, the negative relationship between currency and total private sector deposits confirms that an increase in currency depletes deposits, which in turn hurts economic growth by restricting supply of loanable funds with the banks. From a theoretical standpoint, when we attempt to investigate determinants of currency deposits ratio through graphical analysis, inflation, government budgetary borrowing, industrial production index, investment in National Saving Schemes, remittances inflow, and wheat procurement are found to be the prominent factors behind increasing currency deposits ratio. The note also includes the econometric estimation of these factors
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