1,237 research outputs found
Intermittency in local field potentials recorded from the thalamus of patients with essential tremor
Microcanonical studies concerning the recent experimental evaluations of the nuclear caloric curve
The microcanonical multifragmentation model from [Al. H. Raduta and Ad. R.
Raduta, Phys. Rev. C 55, 1344 (1997); 56, 2059 (1997); 59, 323 (1999)] is
refined and improved by taking into account the experimental discrete levels
for fragments with and by including the stage of sequential decay of
the primary excited fragments. The caloric curve is reevaluated and the heat
capacity at constant volume curve is represented as a function of excitation
energy and temperature. The sequence of equilibrated sources formed in the
reactions studied by the ALADIN group (Au+Au at 600, 800 and
1000 MeV/nucleon bombarding energy) is deduced by fitting simultaneously the
model predicted mean multiplicity of intermediate mass fragments ()
and charge asymmetry of the two largest fragments () versus bound
charge () on the corresponding experimental data. Calculated HeLi
isotopic temperature curves as a function of the bound charge are compared with
the experimentally deduced ones.Comment: 13 pages, 4 figure
Optogenetics and deep brain stimulation neurotechnologies
Brain neural network is composed of densely packed, intricately wired neurons whose activity patterns ultimately give rise to every behavior, thought, or emotion that we experience. Over the past decade, a novel neurotechnique, optogenetics that combines light and genetic methods to control or monitor neural activity patterns, has proven to be revolutionary in understanding the functional role of specific neural circuits. We here briefly describe recent advance in optogenetics and compare optogenetics with deep brain stimulation technology that holds the promise for treating many neurological and psychiatric disorders
Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes
Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium,
thirty-five technetium, and thirty-eight ruthenium isotopes have been observed
and the discovery of these isotopes is discussed here. For each isotope a brief
synopsis of the first refereed publication, including the production and
identification method, is presented.Comment: To be published in Atomic Data and Nuclear Data Table
Spallation reactions. A successful interplay between modeling and applications
The spallation reactions are a type of nuclear reaction which occur in space
by interaction of the cosmic rays with interstellar bodies. The first
spallation reactions induced with an accelerator took place in 1947 at the
Berkeley cyclotron (University of California) with 200 MeV deuterons and 400
MeV alpha beams. They highlighted the multiple emission of neutrons and charged
particles and the production of a large number of residual nuclei far different
from the target nuclei. The same year R. Serber describes the reaction in two
steps: a first and fast one with high-energy particle emission leading to an
excited remnant nucleus, and a second one, much slower, the de-excitation of
the remnant. In 2010 IAEA organized a worskhop to present the results of the
most widely used spallation codes within a benchmark of spallation models. If
one of the goals was to understand the deficiencies, if any, in each code, one
remarkable outcome points out the overall high-quality level of some models and
so the great improvements achieved since Serber. Particle transport codes can
then rely on such spallation models to treat the reactions between a light
particle and an atomic nucleus with energies spanning from few tens of MeV up
to some GeV. An overview of the spallation reactions modeling is presented in
order to point out the incomparable contribution of models based on basic
physics to numerous applications where such reactions occur. Validations or
benchmarks, which are necessary steps in the improvement process, are also
addressed, as well as the potential future domains of development. Spallation
reactions modeling is a representative case of continuous studies aiming at
understanding a reaction mechanism and which end up in a powerful tool.Comment: 59 pages, 54 figures, Revie
Neuropathic pain: redefinition and a grading system for clinical and research purposes.
Pain usually results from activation of nociceptive afferents by actually or potentially tissue-damaging stimuli. Pain may also arise by activity generated within the nervous system without adequate stimulation of its peripheral sensory endings. For this type of pain, the International Association for the Study of Pain introduced the term neuropathic pain, defined as "pain initiated or caused by a primary lesion or dysfunction in the nervous system." While this definition has been useful in distinguishing some characteristics of neuropathic and nociceptive types of pain, it lacks defined boundaries. Since the sensitivity of the nociceptive system is modulated by its adequate activation (e.g., by central sensitization), it has been difficult to distinguish neuropathic dysfunction from physiologic neuroplasticity. We present a more precise definition developed by a group of experts from the neurologic and pain community: pain arising as a direct consequence of a lesion or disease affecting the somatosensory system. This revised definition fits into the nosology of neurologic disorders. The reference to the somatosensory system was derived from a wide range of neuropathic pain conditions ranging from painful neuropathy to central poststroke pain. Because of the lack of a specific diagnostic tool for neuropathic pain, a grading system of definite, probable, and possible neuropathic pain is proposed. The grade possible can only be regarded as a working hypothesis, which does not exclude but does not diagnose neuropathic pain. The grades probable and definite require confirmatory evidence from a neurologic examination. This grading system is proposed for clinical and research purposes
Національно-демократичні об'єднання та політичні партії в Україні кінця XIX - початку XX століття
Deep brain stimulation (DBS) has become increasingly important for the treatment and relief of neurological disorders such as Parkinson's disease, tremor, dystonia and psychiatric illness. As DBS implantations and any other stereotactic and functional surgical procedure require accurate, precise and safe targeting of the brain structure, the technical aids for preoperative planning, intervention and postoperative follow-up have become increasingly important. The aim of this paper was to give and overview, from a biomedical engineering perspective, of a typical implantation procedure and current supporting techniques. Furthermore, emerging technical aids not yet clinically established are presented. This includes the state-of-the-art of neuroimaging and navigation, patient-specific simulation of DBS electric field, optical methods for intracerebral guidance, movement pattern analysis, intraoperative data visualisation and trends related to new stimulation devices. As DBS surgery already today is an important technology intensive domain, an "intuitive visualisation" interface for improving management of these data in relation to surgery is suggested
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Pain neuroimaging in humans: a primer for beginners and non-imagers
The field of human pain neuroimaging has exploded in the last two decades. During this time, the broader neuroimaging community has continued to investigate and refine methods. Another key to progress is exchange with clinicians and pain scientists working with other model systems and approaches. These collaborative efforts require that non-imagers be able to evaluate and assess the evidence provided in these papers. Likewise, new trainees must design rigorous and reliable pain imaging experiments. Here, we provide a guideline for designing, reading, evaluating, analyzing, and reporting results of a pain neuroimaging experiment, with a focus on functional and structural MRI. We focus in particular on considerations that are unique to neuroimaging studies of pain in humans, including study design and analysis, inferences that can be drawn from these studies, and the strengths and limitations of the approach. This article provides an overview of the concepts and considerations of structural and functional MRI neuroimaging studies. The primer is written for those who are not familiar with brain imaging. We review key concepts related to recruitment and study sample, experimental design, data analysis and data interpretation. [Abstract copyright: Copyright © 2018. Published by Elsevier Inc.
Neonatal Erythema Multiforme: A Case Report
Erythema multiforme (EM) is an extremely rare condition in infancy. To the best of our knowledge, there have been only three cases of neonatal EM described in the literature, and no such cases have been reported in Korea. A preterm neonate born at 35 weeks and six days of gestation presented with multiple annular erythematous patches with a targetoid shape over his entire body at 36 days of age (corrected age of 7 days). He had no systemic symptoms except for transient mild fever. No triggering factor except for hepatitis B and BCG vaccination was found. Neutropenia was noted upon laboratory analysis. Skin biopsy specimens showed findings suggestive of erythema multiforme. The skin lesions improved rapidly upon administration of intravenous methylprednisolone; however, neutropenia continued for a much longer period. The significance of neutropenia with respect to the development of EM was not clarified. There has been no recurrence of skin lesions over a one-year follow-up period
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