2,125 research outputs found
Identification of gait phases with neural networks for smooth transparent control of a lower limb exoskeleton
Lower limbs exoskeletons provide assistance during standing, squatting, and walking. Gait dynamics, in particular, implies a change in the configuration of the device in terms of contact points, actuation, and system dynamics in general. In order to provide a comfortable experience and maximize performance, the exoskeleton should be controlled smoothly and in a transparent way, which means respectively, minimizing the interaction forces with the user and jerky behavior due to transitions between different configurations. A previous study showed that a smooth control of the exoskeleton can be achieved using a gait phase segmentation based on joint kinematics. Such a segmentation system can be implemented as linear regression and should be personalized for the user after a calibration procedure. In this work, a nonlinear segmentation function based on neural networks is implemented and compared with linear regression. An on-line implementation is then proposed and tested with a subject
Are leukocyte and platelet abnormalities and complete blood count ratios potential prognostic markers in canine sepsis?
Background: Sepsis is a common disease in which early diagnosis and prognosis assessment are the main aims in order to arrange a prompt and effective treatment. Objectives: (1) To compare leukogram parameters (WBC, segmented and band neutrophils,lymphocytes,monocytes),plateletcount(PLT),meanplateletvolume(MPV), and some leukocyte/platelet ratio such as NLR, NBNLR, PLR, and MLR between dogs with systemic inflammatory response syndrome (SIRS) and sepsis. (2) To investigate any difference in the trend of these latter parameters between survivors and non-survivors septic dogs. Animals: 57 dogs with confirmed sepsis and 57 dogs with non-septic SIRS. Methods: A review of the medical records was conducted in order to find dogs with sepsis. Sepsis was defined as the presence of an infectious focus with fulfillment of systemic inflammatory response syndrome criteria (SIRS). Septic dogs had to have a CBC at admission and another CBC within 48h from the previous timepoint. Purebreds with CBC breed-related abnormalities were excluded, together with dogs without confirmed sepsis and dogs with only a single CBC. NLR, NBNLR, PLR, and MLR were calculated. Univariate analysis of all blood parameters studied was assessed between SIRS and septicdogs. Generalized Estimating Equations models for repeated measures were used to test if the blood parameters studied were modified between survivors and non-survivors in the septic group. Results: Septic dogs had lower median segmented neutrophils count and NLR compared to SIRSdogs (p=0.02andp=0.04, respectively).Lastly,septicdogs hada higherprevalenceoftoxicneutrophilthanSIRSdogs(p=0.01).Wefoundthatfora1-unit increase of PLR and MLR, the risk of death increased by 50.5 and 60%, respectively. Conclusion and Clinical Importance: Evaluation of NLR at hospital admission may be a useful marker of inflammation, although it showed low sensitivity in differentiating SIRS and septic dogs. The monitoring of some CBC parameters, especially PLR and MLR may be useful in the establishment of prognosis in septic dogs
Intravenous lipid emulsion and dexmedetomidine for treatment of feline permethrin intoxication: A report from 4 cases
Four cases of feline permethrin intoxication are described. The cause of intoxication is the application of canine permethrin spot-on product (Advantix®, Bayer) by the owners. Principal clinical guidelines recommends the use of anticonvulsant drugs to treat seizures or neurological symptoms after initial stabilization and dermal decontamination. The use of lipid emulsion had an increasing interest in the last decade for treatment of toxicosis caused by lipophylic drugs as reported in human and in veterinary medical practices. All cats presented in this study, were treated with intravenous lipid emulsion (ILE) at variable dosages, and dexmedetomidine was also administered by intravenous way. No adverse reaction such as thrombophlebitis, overload circulation or others was noticed during and after administration of ILE. Dexmedetomidine was proved to be helpful in tranquillizing the cats. All cats were discharged in good condition faster than other cases treated without their use
Renal Measures in Healthy Italian Trotter Foals and Correlation Between Renal and Biometric Measures: Preliminary Study
The aim of this study was to evaluate ultrasonographic renal measures in healthy foals aged 1–6 weeks and to verify the correlation between biometric measures to ultrasonographic renal ones. A total of nine Italian trotter foals born in the same stud farm and underwent similar management conditions were enrolled. Inclusion criteria were normal gestation time, unassisted delivery, and normal physical examination at all evaluation times. Length and height of both kidneys were measured by ultrasound weekly from 1 to 6 weeks of life, along with the thoracic and the middle third of the metacarpal area circumferences. Data were expressed as mean and standard deviation, and distribution was evaluated. One-way analysis of variance (ANOVA) was applied to verify differences related to time. The Pearson correlation test was carried out to evaluate the linearity between time versus all the parameters measured. Student's t test was used to verify differences in ultrasound measures between right and left kidney at all recorded times. The Pearson test was applied to a mean-variance matrix to verify the correlation between each biometrical versus all renal measures. Significance level was set at P <.05. One-way ANOVA showed differences in biometric and renal measures related to time. Correlation test revealed a linear growth. Differences in ultrasound renal measures between right and left kidney were obtained. Correlation was found between biometrical parameters versus kidney measures. Renal measures and differences between left and right kidneys were in line with literature. Correlation test revealed a linear growth. Renal growth is correlated with age and biometric measure
Temporal and Spatial Aspects of Gas Release During the 2010 Apparition of Comet 103P/Hartley-2
We report measurements of eight primary volatiles (H2O, HCN, CH4, C2H6,
CH3OH, C2H2, H2CO, and NH3) and two product species (OH and NH2) in comet
103P/Hartley-2 using high dispersion infrared spectroscopy. We quantified the
long- and short-term behavior of volatile release over a three-month interval
that encompassed the comet's close approach to Earth, its perihelion passage,
and flyby of the comet by the Deep Impact spacecraft during the EPOXI mission.
We present production rates for individual species, their mixing ratios
relative to water, and their spatial distributions in the coma on multiple
dates. The production rates for water, ethane, HCN, and methanol vary in a
manner consistent with independent measures of nucleus rotation, but mixing
ratios for HCN, C2H6, & CH3OH are independent of rotational phase. Our results
demonstrate that the ensemble average composition of gas released from the
nucleus is well defined, and relatively constant over the three-month interval
(September 18 through December 17). If individual vents vary in composition,
enough diverse vents must be active simultaneously to approximate (in sum) the
bulk composition of the nucleus. The released primary volatiles exhibit diverse
spatial properties which favor the presence of separate polar and apolar ice
phases in the nucleus, establish dust and gas release from icy clumps (and
also, directly from the nucleus), and provide insights into the driver for the
cyanogen (CN) polar jet. The spatial distributions of C2H6 & HCN along the
near-polar jet (UT 19.5 October) and nearly orthogonal to it (UT 22.5 October)
are discussed relative to the origin of CN. The ortho-para ratio (OPR) of water
was 2.85 \pm 0.20; the lower bound (2.65) defines Tspin > 32 K. These values
are consistent with results returned from ISO in 1997.Comment: 18 pages, 3 figures, to be published in: Astrophysical Journal
Letter
Creation, doubling, and splitting, of vortices in intracavity second harmonic generation
We demonstrate generation and frequency doubling of unit charge vortices in a
linear astigmatic resonator. Topological instability of the double charge
harmonic vortices leads to well separated vortex cores that are shown to
rotate, and become anisotropic, as the resonator is tuned across resonance
Quantum harmonic oscillator systems with disorder
We study many-body properties of quantum harmonic oscillator lattices with
disorder. A sufficient condition for dynamical localization, expressed as a
zero-velocity Lieb-Robinson bound, is formulated in terms of the decay of the
eigenfunction correlators for an effective one-particle Hamiltonian. We show
how state-of-the-art techniques for proving Anderson localization can be used
to prove that these properties hold in a number of standard models. We also
derive bounds on the static and dynamic correlation functions at both zero and
positive temperature in terms of one-particle eigenfunction correlators. In
particular, we show that static correlations decay exponentially fast if the
corresponding effective one-particle Hamiltonian exhibits localization at low
energies, regardless of whether there is a gap in the spectrum above the ground
state or not. Our results apply to finite as well as to infinite oscillator
systems. The eigenfunction correlators that appear are more general than those
previously studied in the literature. In particular, we must allow for
functions of the Hamiltonian that have a singularity at the bottom of the
spectrum. We prove exponential bounds for such correlators for some of the
standard models
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