682 research outputs found
Systemic lupus erythematosus: immunopathogenesis and novel therapeutic targets
Systemic lupus erythematosus (SLE) is the prototype of autoimmune diseases with multiorgan involvement. SLE presents many genetic and epigenetic associations and the pathogenesis is characterized by a complex network of alterations affecting both adaptative and innate immunity. The disclosure of novel mechanisms of SLE pathogenesis suggested new therapeutic targets, based on interference with the cytokine pathways or on depletion of the immune cells
A New Procedure for Combining UAV-Based Imagery and Machine Learning in Precision Agriculture
Drone images from an experimental field cropped with sugar beet with a high diffusion of weeds taken from different flying altitudes were used to develop and test a machine learning method for vegetation patch identification. Georeferenced images were combined with a hue-based preprocessing analysis, digital transformation by an image embedder, and evaluation by supervised learning. Specifically, six of the most common machine learning algorithms were applied (i.e., logistic regression, k-nearest neighbors, decision tree, random forest, neural network, and support-vector machine). The proposed method was able to precisely recognize crops and weeds throughout a wide cultivation field, training from single partial images. The information has been designed to be easily integrated into autonomous weed management systems with the aim of reducing the use of water, nutrients, and herbicides for precision agriculture
Comparison of positional accuracy between RTK and RTX GNSS gased on the autonomous agricultural vehicles under field conditions
Currently, many systems (machine vision, high resolution remote sensing, global positioning systems, and
odometry techniques) have been integrated into agricultural e
quipment to increase the efficiency, productivity, and safety
of the individual in all field activities. This study focused upon assessing a satellite-based localization solution used in
straight path guidance of an autonomou
s vehicle developed for ag
ricultural applica
tions. The autonom
ous agricultural
vehicle was designed and constructed under RHEA (Robot fleets for highly effective agriculture and forestry management)
project and is part of a three-unit fleet of similar vehicles. Static tests showed that 99% of all positions are placed within
a
circle with a 2.9 cm radius centered at the geo-position usi
ng real-time satellite corrections (RTX). Dynamic tests between
rows demonstrated a mean (N=610) of the standard deviation for real-time base station corrections (RTK) of 1.43 cm and
for real-time satellite corrections (RTX) of 2.55 cm. These re
sults demonstrate that the tractor was able to track each
straight line with high degree of accuracy. The integration of a Global Navigation Satellite System (GNSS) with sensors
(e.g., inertial sensor, altimeters, odomet
ers, etc.) within the vehicle showed th
e potential of autonomous tractors for
expanding agricultural applications utilizing this technology.European Union FP7/2007-201
CSF/serum matrix metallopeptidase-9 ratio discriminates neuro Behcet from multiple sclerosis
In neuro Behcet disease with multiple sclerosis-like features, diagnosis could be challenging. Here, we studied the cerebrospinal fluid and serum inflammatory profile of 11 neuro Behcet and 21 relapsing-remitting multiple sclerosis patients. Between the soluble factors analyzed (MMP9, TNF, IL6, CXCL13, CXCL10, CXCL8, IFN, IL10, IL17, IL23, and others) we found MMP9 increased in neuro Behcet serum compared to multiple sclerosis and decreased in cerebrospinal fluid. Furthermore, neuro Behcet analysis of circulating natural killer CD56(DIM) subset suggests their potential involvement in increased MMP9 production. We believe that these findings may have a translational utility in clinical practice
Nonlinear diffusion & thermo-electric coupling in a two-variable model of cardiac action potential
This work reports the results of the theoretical investigation of nonlinear
dynamics and spiral wave breakup in a generalized two-variable model of cardiac
action potential accounting for thermo-electric coupling and diffusion
nonlinearities. As customary in excitable media, the common Q10 and Moore
factors are used to describe thermo-electric feedback in a 10-degrees range.
Motivated by the porous nature of the cardiac tissue, in this study we also
propose a nonlinear Fickian flux formulated by Taylor expanding the voltage
dependent diffusion coefficient up to quadratic terms. A fine tuning of the
diffusive parameters is performed a priori to match the conduction velocity of
the equivalent cable model. The resulting combined effects are then studied by
numerically simulating different stimulation protocols on a one-dimensional
cable. Model features are compared in terms of action potential morphology,
restitution curves, frequency spectra and spatio-temporal phase differences.
Two-dimensional long-run simulations are finally performed to characterize
spiral breakup during sustained fibrillation at different thermal states.
Temperature and nonlinear diffusion effects are found to impact the
repolarization phase of the action potential wave with non-monotone patterns
and to increase the propensity of arrhythmogenesis
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