4,973 research outputs found
Effects of isolation conditions on the cytometric evaluation of chromatin structure in rat myocardial nuclei
No full textSensorimotor integration during stance: Processing time of active or passive addition or withdrawal of visual or haptic information.
No full textVision (V) and touch (T) help stabilize our standing body, but little is known on the time-interval necessary for the brain to process the sensory inflow (or its removal) and exploit the new information (or counteract its removal). We have estimated the latency of onset and the time-course of the changes in postural control mode following addition or withdrawal of sensory information and the effect of anticipation thereof. Ten subjects stood in tandem position. They wore LCD goggles that allowed or removed vision, or lightly touched (eyes-closed) with the index finger (haptic stimulation) a pad that could be suddenly lowered (passive task). In different sessions, sensory shifts were deliberately produced by opening (or closing) the eyes or touching the pad (or lifting the finger) (active task). We recorded eyelid movement and finger force (<1 N), sway of center of foot pressure (CoP), electromyogram (EMG) of soleus, tibialis and peroneus muscle, bilaterally, and of extensor indicis. The latency of the CoP and EMG changes following the shifts were statistically estimated on the averaged traces of 50 repetitions per condition. Muscle activity and sway adaptively decreased in amplitude on adding stabilizing visual or haptic information. The time-interval from the sensory shift to decrease in EMG and sway was ∼0.5–2 s under both conditions. It was shorter for tibialis than peroneus or soleus and shorter for visual than haptic shift. CoP followed the tibialis by ∼0.2 s. Slightly shorter intervals were observed following active sensory shifts. Latencies of EMG and postural changes were the shortest on removal of both haptic and visual information. Subsequently, the time taken to reach the steady-state was ∼1–3 s under both active and passive tasks. A startle response at ∼100 ms could precede EMG changes. Reaction-time contractions in response to sensory shifts appeared at ∼200 ms, earlier than the adaptive changes. Changes in postural behavior require a finite amount of time from visual or haptic shift, much longer than reflexes or rapid voluntary responses, suggesting a time-consuming central integration process. This process is longer on addition than removal of haptic information, indicating a heavier computational load. These findings should be taken into account when considering problems of sensorimotor integration in elderly subjects or patients and when designing simulation models of human balance
Interactively using Semantic Web knowledge: Creating scalable abstractions with FacetOntology
No full textThe amount of knowledge accessible on the Semantic Web is growing, and there is a need for a scalable solution to facilitate exploring that data. Currently approaches to exploring Semantic Web data either focus on exploring resources individually, following links during exploration, and making little use of collated data, or take the approach of collating and aligning multiple sources into one store for one purpose, and hand-crafting a specific browsing interface onto it. We present an approach that provides a scalable browsing interface, which can browse knowledge from the Semantic Web at will. Our approach creates abstractions of knowledge, collated into facets, which are described using FacetOntology. FacetOntology facilitates describing facets from RDF data, suitable for use in creating datasets for faceted browsing
HCV-negative mixed cryoglobulinemia: Facts and fancies
No full textApproximately 10% of the population with mixed cryoglobulinemia (MC) have no evidence of HCV infection. In these patients, a wide number of infectious agents have been associated with cryoglobulinemia, although only HBV and HIV have a well- documented role in causing the disorder. Several connective tissue (mainly systemic lupus erythematosus, Sjögren's syndrome, and systemic sclerosis) and lymphoproliferative (in most cases B-cell non-Hodgkin lymphoma) diseases have also been shown to play an etiologic role in some cases of HCV-negative MC. Fewer than 5% of cryoglobulinemic patients show no identifiable underlying diseases and they are therefore considered as having essential MC. In HCV-negative MC, an occult HCV infection should also be taken into account. The clinical manifestations, cryoglobulin levels, and survival rates in MC patients with and without HCV seem not to differ significantly, although the data are conflicting. In symptomatic MC, therapy should aim at improvement or resolution of clinical manifestations, as elimination of the causative factor is impossible in most cases
Growth Morphologies and Mechanisms of Non-Equilibrium Solidified MC Carbide
No full textGrowth morphologies and mechanisms of the carbide of group IVB and VB elements (MC carbide), a typical faceted crystal, were studied with an estimated cooling rate from 102 to 105 K/s. Results showed that although the growth morphologies of the MC carbide vary remarkably with solidification cooling rate, the solid/liquid interface is always atomically smooth, and the growth mechanisms are always lateral growth. The growth mechanism transition from lateral to continuous growth mode, which was predicted by the classic crystal growth theory, was not observed for the TiC type MC carbide within the estimated cooling rate range of 102?105 K/s
Principal mixed cryoglobulinemia (MC) manifestations present in the 75 HCV patients with MC (MC-HCV).
No full text<p>Principal mixed cryoglobulinemia (MC) manifestations present in the 75 HCV patients with MC (MC-HCV).</p
Ruth Klüger: la creatività per non “smarrirsi strada facendo”
No full textR. Klüger, a jewish viennese, a US citizen and a germanist, is the Author of two autobiographies “weiter leben”and “unterwegs versore”. Written in a style which alternates between essay and poetry, account and recollection, they are the occasion for the Author to establish a dialogue with the women having as a focus the exchange of experiences and reflections over the status of the feminine emancipation
Eutectic MC Carbide Growth Morphologies of a Laser Clad TiC/FeAl Composite Coating
No full textIn this paper, eutectic MC carbide growth morphology and its evolution with laser scanning speed were studied comprehensively of a laser clad MC carbide reinforced FeAl intermetallic matrix composite coating. As the laser scanning speed increased, the growth morphology of eutectic MC carbide was found to be needle-aligned annulation, butterfly-like and well-developed dendrite
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