3,886 research outputs found
Protective Effects of Dimedone Pyrone on Podocytes in Rats with Diabetic Nephropathy
Purpose: To investigate the effect of dimedone pyrone (DP) on podocytes in rats with diabetic nephropathy (DN).Methods: The rats were randomly assigned into 5 experimental groups (n = 10), viz, non-diabetic control with no treatment (ND/NT), diabetic with no treatment (DG/NT), diabetic treated with 5 mg/kg dimedone pyrone (DG/DP 5), diabetic treated with 10 mg/kg dimedone pyrone (DG/DP 10) and diabetic treated with 20 mg/kk dimedone pyrone (DG/DP 20) group. Clinical parameters, including 24 h urinary protein, blood urea nitrogen (BUN), serum creatinine (SCR), blood glucose (GLU), and kidney weight (KW)/body weight (BW) were determined after 12 weeks of treatment. Hematoxylin and eosin staining was used to examine renal pathological changes while transmission electron microscopy (TEM) was employed for evaluation of structural changes in the podocytes. The expression levels of nephrin and podocin were evaluated using immunofluorescence staining.Results: Dimedone pyrone caused a significant decrease in SCR, BUN, GLU, KW/BW and 24 h urine protein in DG/DP 20 group compared to DG/NT group. Furthermore, incidences of glomerular disorders, chronic tubulo-interstitial damage and glomerular podocyte lesions decreased significantly following dimedone pyrone treatment. Glomeruli, tubules and podocytes exhibited pathomorphological improvements while nephrin and podocin protein expression levels were significantly higher in the nephridial tissue. Decrease in relative kidney weight (KW/BW) and 24 h urinary protein level were improved significantly on treatment with dimedone pyrone. Moreover, glomerular disorder, chronic tubulo-interstitial damage and glomerular podocyte lesions were also suppressed. The improvement was more significant in DG/DP 20 compared to DG/DP 5 and DG/DP 10 groups.Conclusion: Dimedone pyrone exhibits a protective effect on the podocytes of rats and may be of therapeutic importance in the treatment of diabetic nephropathy.Keywords: Dimedone pyrone, Podocin, Diabetic neuropathy, Nephrin, Glomerular disorder
Contact of Single Asperities with Varying Adhesion: Comparing Continuum Mechanics to Atomistic Simulations
Atomistic simulations are used to test the equations of continuum contact
mechanics in nanometer scale contacts. Nominally spherical tips, made by
bending crystals or cutting crystalline or amorphous solids, are pressed into a
flat, elastic substrate. The normal displacement, contact radius, stress
distribution, friction and lateral stiffness are examined as a function of load
and adhesion. The atomic scale roughness present on any tip made of discrete
atoms is shown to have profound effects on the results. Contact areas, local
stresses, and the work of adhesion change by factors of two to four, and the
friction and lateral stiffness vary by orders of magnitude. The microscopic
factors responsible for these changes are discussed. The results are also used
to test methods for analyzing experimental data with continuum theory to
determine information, such as contact area, that can not be measured directly
in nanometer scale contacts. Even when the data appear to be fit by continuum
theory, extracted quantities can differ substantially from their true values
Remission of obesity among a nationally representative sample of US children
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147066/1/ijpo12457.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147066/2/ijpo12457_am.pd
Extreme case of Faraday effect: magnetic splitting of ultrashort laser pulses in plasmas
The Faraday effect, caused by a magnetic-field-induced change in the optical
properties, takes place in a vast variety of systems from a single atomic layer
of graphenes to huge galaxies. Currently, it plays a pivot role in many
applications such as the manipulation of light and the probing of magnetic
fields and material's properties. Basically, this effect causes a polarization
rotation of light during its propagation along the magnetic field in a medium.
Here, we report an extreme case of the Faraday effect where a linearly
polarized ultrashort laser pulse splits in time into two circularly polarized
pulses of opposite handedness during its propagation in a highly magnetized
plasma. This offers a new degree of freedom for manipulating ultrashort and
ultrahigh power laser pulses. Together with technologies of ultra-strong
magnetic fields, it may pave the way for novel optical devices, such as
magnetized plasma polarizers. In addition, it may offer a powerful means to
measure strong magnetic fields in laser-produced plasmas.Comment: 18 pages, 5 figure
A new approach to the derivation of dynamic information from ionosonde measurements
International audienceA new approach is developed to derive dynamic information near the peak of the ionospheric F-layer from ionosonde measurements. This approach avoids deducing equivalent winds from the displacement of the observed peak height from a no-wind equilibrium height, so it need not determine the no-wind equilibrium height which may limit the accuracy of the deduced winds, as did the traditional servo theory. This approach is preliminarily validated with comparisons of deduced equivalent winds with the measurements from the Fabry-Perot interferometer, the Millstone Hill incoherent scatter radar and with previous works. Examples of vertical components of equivalent winds (VEWs), over Wuhan (114.4° E, 30.6° N, 45.2° dip), China in December 2000 are derived from Wuhan DGS-256 Digisonde data. The deduced VEWs show large day-to-day variations during the winter, even in low magnetic activity conditions. The diurnal pattern of average VEWs is more complicated than that predicted by the empirical Horizontal Wind Model (HWM). Using an empirical electric field model based on the observations from Jicamarca radar and satellites, we investigate the contributions to VEWs from neutral winds and from electric fields at the F-layer peak. If the electric field model is reasonable for Wuhan during this period, the neutral winds contribute mostly to the VEWs, and the contribution from the E × B drifts is insignificant
Fire and flooding resilience in Mimosa L. of the Brazilian Pantanal
PosterThe Pantanal ecoregion, in south-central Brazil, is one of the largest foodplains in the world. Cycles of fooding and periodic fre have been determinant to the diversity of species in the ecoregion. In the fora of Pantanal, Leguminosae is one of the most rich families, and Mimosa is its most diversifed genus. Species of this genus are widely distributed and occur in the capões, sandy ridges and monominant stands (e.g. Cambarazal, Carandazal and Paratudal), in addition to native grasslands and pasture areas. In the Cerrado ecoregion, adaptations to fre have been recognized in some species of Mimosa. However, there is no data in the Pantanal ecoregion about which species of Mimosa are resilient to fre and/or fooding. This study aimed to investigate morphological adaptation in Mimosa in terms of resilience to fre and fooding. We verifed 45 specifc and infraspecifc taxa of Mimosa occurring in the Brazilian Pantanal, by means of the revision of literature, herbarium data, personal observations, plant collections and feld notesInstituto de Recursos BiológicosFil: Nogueira, Luan. Universidade Federal de Mato Grosso do Sul, BrasilFil: Morales, Matias. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Biológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Morón. Facultad de Agronomía y Ciencias Agroalimentarias; ArgentinaFil: Sartori, Angela Lucia. Universidade Federal de Mato Grosso do Sul, Brasi
Coupling of Light and Mechanics in a Photonic Crystal Waveguide
Observations of thermally driven transverse vibration of a photonic crystal
waveguide (PCW) are reported. The PCW consists of two parallel nanobeams with a
240 nm vacuum gap between the beams. Models are developed and validated for the
transduction of beam motion to phase and amplitude modulation of a weak optical
probe propagating in a guided mode (GM) of the PCW for probe frequencies far
from and near to the dielectric band edge. Since our PCW has been designed for
near-field atom trapping, this research provides a foundation for evaluating
possible deleterious effects of thermal motion on optical atomic traps near the
surfaces of PCWs. Longer term goals are to achieve strong atom-mediated links
between individual phonons of vibration and single photons propagating in the
GMs of the PCW, thereby enabling opto-mechanics at the quantum level with
atoms, photons, and phonons. The experiments and models reported here provide a
basis for assessing such goals, including sensing mechanical motion at the
Standard Quantum Limit (SQL).Comment: 13 pages, 13 figure
Modelling time course gene expression data with finite mixtures of linear additive models
Summary: A model class of finite mixtures of linear additive models is presented. The component-specific parameters in the regression models are estimated using regularized likelihood methods. The advantages of the regularization are that (i) the pre-specified maximum degrees of freedom for the splines is less crucial than for unregularized estimation and that (ii) for each component individually a suitable degree of freedom is selected in an automatic way. The performance is evaluated in a simulation study with artificial data as well as on a yeast cell cycle dataset of gene expression levels over time
- …