3,221 research outputs found
Protective effects of flavonoids from corn silk on oxidative stress induced by exhaustive exercise in mice
The present study aims at exploring the effects of flavonoids from corn silk (FCS) on oxidative stress induced by exhaustive exercise in mice. Sixty mice were randomized into 3 groups: Low-dose FCS treatment group (LFG), high-dose FCS treatment group (HFG) and control group (CG). The mice were treated with FCS (100 and 400 mg/kg) or placebo (distilled water) by daily oral gavage for 28 days. After the last treatment, animals were submitted to treadmill for exhaustion and running time, malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPX) levels were measured. The results suggested that FCS could elevate the exercise tolerance of mice, and provide protection against oxidative stress induced by exhaustive exercise in mice, by inhibiting lipid per-oxidation and increasing anti-oxidant enzymes levels.Key words: Flavonoids from corn silk, oxidative stress, exhaustive exercise, mic
Exploiting Magnetic Resonance Angiography Imaging Improves Model Estimation of BOLD Signal
The change of BOLD signal relies heavily upon the resting blood volume fraction () associated with regional vasculature. However, existing hemodynamic data assimilation studies pretermit such concern. They simply assign the value in a physiologically plausible range to get over ill-conditioning of the assimilation problem and fail to explore actual . Such performance might lead to unreliable model estimation. In this work, we present the first exploration of the influence of on fMRI data assimilation, where actual within a given cortical area was calibrated by an MR angiography experiment and then was augmented into the assimilation scheme. We have investigated the impact of on single-region data assimilation and multi-region data assimilation (dynamic cause modeling, DCM) in a classical flashing checkerboard experiment. Results show that the employment of an assumed in fMRI data assimilation is only suitable for fMRI signal reconstruction and activation detection grounded on this signal, and not suitable for estimation of unobserved states and effective connectivity study. We thereby argue that introducing physically realistic in the assimilation process may provide more reliable estimation of physiological information, which contributes to a better understanding of the underlying hemodynamic processes. Such an effort is valuable and should be well appreciated
Novel critical point drying (CPD) based preparation and transmission electron microscopy (TEM) imaging of protein specific molecularly imprinted polymers (HydroMIPs)
We report the transmission electron microscopy (TEM) imaging of a hydrogel-based molecularly imprinted polymer (HydroMIP) specific to the template molecule bovine haemoglobin (BHb). A novel critical point drying based sample preparation technique was employed to prepare the molecularly imprinted polymer (MIP) samples in a manner that would facilitate the use of TEM to image the imprinted cavities, and provide an appropriate degree of both magnification and resolution to image polymer architecture in the <10 nm range. For the first time, polymer structure has been detailed that clearly displays molecularly imprinted cavities, ranging from 5-50 nm in size, that correlate (in terms of size) with the protein molecule employed as the imprinting template. The modified critical point drying sample preparation technique used may potentially play a key role in the imaging of all molecularly imprinted polymers, particularly those prepared in the aqueous phase
Integrated magnetoelectric devices based on interfacial magnetoelectric coupling effects
Adhesion Induced DNA Naturation
DNA adsorption and naturation is modeled via two interacting flexible
homopolymers coupled to a solid surface. DNA denatures if the entropy gain for
unbinding the two strands overcomes the loss of binding energy. When adsorbed
to a surface, the entropy gain is smaller than in the bulk, leading to a
stronger binding and, upon neglecting self-avoidance, absence of a denatured
phase. Now consider conditions where the binding potentials are too weak for
naturation, and the surface potential too weak to adsorb single strands. In a
variational approach it is shown that their combined action may lead to a
naturated adsorbed phase. Conditions for the absence of naturation and
adsorption are derived too. The phase diagram is constructed qualitatively.Comment: 4 pages, 1 figur
Flexible all-solid-state supercapacitors based on transition metal oxide nanocomposites
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