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The exterior Calderón operator for non-spherical objects

This paper deals with the exterior Calderón operator for Lipschitz surfaces. We present a new approach of finding the norm of the exterior Calderón operator for this class of surfaces. The basic tool in the treatment is the set of eigenfunctions and eigenvalues of the Laplace-Beltrami operator for the surface. The norm is obtained as an eigenvalue problem of a quadratic form containing the exterioThis paper deals with the exterior Calderón operator for Lipschitz surfaces. We present a new approach of nding the norm of the exterior Calderón operator for this class of surfaces. The basic tool in the treatment is the set of eigenfunctions and eigenvalues of the Laplace-Beltrami operator for the surface. The norm is obtained as an eigenvalue problem of a quadratic form containing the exterior

Heterokaryon-based reprogramming for pluripotency

Embryonic stem (ES) cells have the ability to self-renew, execute multiple lineage paths, and dominantly reprogram differentiated cells upon cell fusion. Here, we describe an approach that reprograms human B lymphocytes toward pluripotency by generating inter-species heterokaryons with mouse ES cells. This induces a human ES-specific gene expression profile, in which the extent and the rapidity of

Transcranial direct current stimulation based on quantitative electroencephalogram combining positive psychotherapy for major depression

Abstract. Frontal cortex activity in the left hemisphere during depression is reduced. Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulation technique that can increase frontal cortex activity. Therapy based on tDCS and positive psychology (PP) therapy was applied improving patients’ quality of life. The present study compared three conditions 29 participants with clinicFrontal cortex activity in the left hemisphere during depression is reduced. Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulation technique that can increase frontal cortex activity. Therapy based on tDCS and positive psychology (PP) therapy was applied improving patients’ quality of life. The present study compared three conditions participants with clinical depression

Hydroxyapatite granule/carrier composites promote new bone formation in cortical defects

BACKGROUND: A great deal of interest has been focused on finding substitutes for autogenous bone grafts. Among the most interesting materials are different calcium phosphate compositions (e.g., hydroxyapatite [HA]), due to their biocompatible properties in hard and soft tissue.PURPOSE: The bone response to porous ceramic HA granules in combination with two lipid and one polysaccharide carrier was

Alteration of PACAP distribution and PACAP receptor binding in the rat sensory nervous system following sciatic nerve transection

Pituitary adenylate cyclase activating polypeptide (PACAP) is a widely expressed neuropeptide that has been involved in nerve regeneration, neurone survival and nociception. In this study, the distribution of PACAP and PACAP-receptors were investigated in rat dorsal root ganglia (DRG), spinal cord and medulla oblongata at 3, 7 or 14 days following unilateral sciatic nerve transection using immunoh

Perforated silicon nerve chips with doped registration electrodes : in vitro performance and in vivo operation

An in vitro model was developed for the study of signal transduction between a Cu-wire, miming a neural signal source, and recording electrodes on perforated silicon chips. Phosphorous doped electrodes were used to achieve an all silicon device. The model was used to study signal amplitude as a function of the spatial position, and distance to the signal source. Recordings of the signal crosstalk

Pituitary adenylate cyclase-activating peptide is upregulated in sensory neurons by inflammation

The neuropeptide pituitary adenylate cyclase-activating peptide (PACAP) is expressed in sensory neurons. Expression of several neuropeptides is up-regulated in sensory neurons following inflammation. To examine whether also PACAP expression is regulated by inflammation, PACAP expression in L5 dorsal root ganglion (DRG) was determined, using in situ hybridization, after unilateral adjuvant-induced

Islet amyloid polypeptide and calcitonin gene-related peptide expression are upregulated in lumbar dorsal root ganglia after unilateral adjuvant-induced inflammation in the rat paw

After unilateral adjuvant-induced inflammation, expression of neuropeptides believed to be involved in the inflammatory response, e.g. substance P and calcitonin gene-related peptide (CGRP), is upregulated in innervating sensory neurons. Islet amyloid polypeptide (IAPP) is structurally related to CGRP and constitutively expressed in sensory CGRP-containing neurons; the role of IAPP in sensory neur

Islet amyloid polypeptide and calcitonin gene-related peptide expression are down-regulated in dorsal root ganglia upon sciatic nerve transection

Islet amyloid polypeptide (IAPP) is structurally related to calcitonin gene-related peptide (CGRP) and has been implicated in glucose homeostasis and diabetes pathogenesis because it is expressed in insulin cells and forms amyloid in pancreatic islets from type II diabetic patients. IAPP is also constitutively co-expressed with CGRP in rat sensory neurons. Whether expression of IAPP is altered by

Tubular versus conventional repair of median and ulnar nerves in the human forearm : early results from a prospective, randomized, clinical study

Injury to a peripheral nerve is followed by local synthesis and release of neurotrophic factors of importance for the regeneration process. This concept was adopted for repair of transected human median and ulnar nerves in the forearm. As an alternative to conventional microsurgical repair of the nerve trunk, silicone tubes of appropriate size were used to enclose the injury zone, intentionally le

Tubular repair of the median nerve in the human forearm. Preliminary findings

Transected median nerves in the forearm of two male patients, 12 and 21 years of age, were treated with a chamber technique leaving a 3 to 5 mm gap between the nerve ends. The nerve ends were enclosed in a silicone tube of such a dimension that would not cause compression of the nerve. Post-operative examination including sensory evaluation and assessment of muscle contraction force was carried ou

Role of macrophages in the stimulation and regeneration of sensory nerves by transposed granulation tissue and temporal aspects of the response

Application of granulation tissue, which is rich in macrophages, to a peripheral nerve induces a conditioning effect, in that it enhances the regeneration capability of peripheral nerves after a test crush lesion. The temporal aspects of this response and the role of macrophages and interleukin-1 beta (IL-1 beta) were studied in the sciatic nerves of 71 rats. Granulation tissue was implanted close

Stimulation of nerve regeneration by macrophages in granulation tissue

The effects of granulation tissue exposure on regeneration of sensory axons after a test crush lesion in rat sciatic nerves were studied. Chromic catgut threads were applied subcutaneously in the back of rats. Three weeks later the surrounding granulation tissue was isolated and transposed to the sciatic or tibial nerve in the same rat. Immunocytochemical, light and electron microscopic evaluation

The Tracking Ratio Station

In ratio control, the control objective is to keep the ratio between two signals, normally flow measurements, at a desired value in spite of variations in setpoints and load disturbances, and possible control signal saturations. This paper presents a new ratio control scheme, the Tracking Ratio Station, that manages to handle all these situations. It is also able to keep the ratio when one of the

Pituitary adenylate cyclase activating peptide expression in the rat dorsal root ganglia : up-regulation after peripheral nerve injury

Pituitary adenylate cyclase activating peptide (PACAP) is expressed in a population of capsaicin-sensitive primary sensory neurons of small to medium size in the rat. In the present report we have examined the effect of sciatic nerve injury (unilateral transection) on PACAP expression (immunocytochemistry, radioimmunoassay, in situ hybridization and northern blot analysis) in dorsal root ganglia a