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OBJECTIVE: To study the efficacy and safety of the use of annual course therapy of choline alfoscerate (CA) as a drug potentially capable of slowing or preventing the transition of amnesic type mild cognitive impairment (aMCI) into clinically pronounced dementia in a three-year open comparative study, as well as to explore the possibility of predicting the preventive effect of such therapy based on a number of clinical and biological parameters. MATERIAL AND METHODS: The study included 100 patients with aMCI, randomly divided into 2 groups: the therapeutic group consisted of 50 patients who received CA course therapy once a year for 3 years (20 intravenous infusions of 1000 mg (4 ml) in 100 ml of saline solution for 4 weeks) and a comparison group of 50 patients who underwent an annual examination at the center and did not receive therapy. Clinical and psychopathological, psychometric, immunological, follow-up, and statistical methods were used. RESULTS: A comparative three-year prospective study conducted in a group of aMCI patients treated with annual course therapy of CA for 3 years and aMCI patients who did not receive therapy with similar initial demographic, diagnostic, psychometric and immunological characteristics showed a lower progression of cognitive deficits (12.2% and 39.1%, respectively) and a lower conversion rate (8.2% and 26.1%, respectively) to dementia in the therapeutic group compared with the comparison group. The differences between the initial and final (after 1, 2 and 3 years of follow-up) cognitive functioning indicators in the therapeutic group and the comparison group were significant (p<0.05) on all scales and tests in favor of the therapeutic group throughout the entire follow-up period. CONCLUSION: The results allow us to consider CA as a possible model of preventive dementia therapy aimed at preventing the progression of cognitive deficits and the development of dementia in people at high risk of developing AD - patients with aMCI.
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Disfunción Cognitiva , Demencia , Glicerilfosforilcolina , Humanos , Disfunción Cognitiva/prevención & control , Disfunción Cognitiva/tratamiento farmacológico , Femenino , Masculino , Anciano , Demencia/prevención & control , Estudios Prospectivos , Glicerilfosforilcolina/uso terapéutico , Glicerilfosforilcolina/administración & dosificación , Resultado del Tratamiento , Persona de Mediana Edad , Progresión de la Enfermedad , Anciano de 80 o más AñosRESUMEN
OBJECTIVE: To determine the long-term (three-year) prognosis of the cognitive deficits progression in elderly people with amnestic mild cognitive impairment (aMCI) based on the analysis of the initial clinical and immunological parameters. MATERIAL AND METHODS: This study is based on a clinical and follow-up study of 252 outpatients with aMCI, who were observed in the Federal State Budgetary Scientific Institution «Mental Health Research Center¼ from 2018 to 2020. The psychometric assessment complex included the following scales and tests: MMSE, MoCA, The 10 words test, BNT, David Wechsler's Scale, subtest 6, CDT, Memory test of 5 geometric shapes, BVRT Test, DRS - Mattis Dementia Rating Scale: Verbal fluency, DRS - Mattis Dementia Rating Scale, The Munsterberg Test. As part of the study, the level of cytokines (TNF-a, IL-1, IL-6, IL-8, IL-10) in the blood serum was determined in all patients by enzyme immunoassay (ELISA), using diagnostic kits manufactured by Cytokine LLC. RESULTS: In patients with a progression of aMCI syndrome, an increase in proinflammatory cytokines IL-1, IL-6, IL-8, TNF-α is initially detected, which may reflect the level of systemic inflammation or functional insufficiency of anti-inflammatory mechanisms. In turn, the group with a subsequent improvement in cognitive functioning, on the contrary, is distinguished by an initially increased level of the anti-inflammatory interleukin system (IL-10). CONCLUSION: We provide new data on the presence of systemic inflammation and immune disturbances and their association with clinical course of disease in the majority of elderly patients with aMCI. CONCLUSION: Signs of a chronic low-level systemic inflammatory response in patients with aMCI is the unfavorable prognosis criterion: in such patients, cognitive deficit significantly progresses or dementia due to Alzheimer disease develops within three years.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Anciano , Disfunción Cognitiva/diagnóstico , Estudios de Seguimiento , Humanos , Pruebas Neuropsicológicas , PronósticoRESUMEN
We use Rice's theory of shot noise random processes to provide a statistical analysis of the evolution of the amplitude and phase of the chaotic optical field from a high-gain, self-amplified, spontaneous-emission (SASE) free-electron laser. The theoretical framework developed is compared with recent frequency-resolved optical-gating measurements of the SASE output at the LEUTL facility at Argonne National Laboratory.
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We introduce a simplified model for the saturation of a self-amplified spontaneous-emission free-electron laser. Within this model, we determine the effect of nonlinearity upon the statistical properties of the output radiation. Comparing our results with the computer simulations of Saldin, Schneidmiller, and Yurkov [The Physics of Free Electron Lasers (Springer-Verlag, Berlin, 2000)], we find that the model provides a good description of the average intensity, field correlation function, and coherence time, but underestimates the intensity fluctuation. Asymmetric spectral broadening phenomena are not included in the model.
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We report the first experimental results on a high-gain harmonic-generation (HGHG) free-electron laser (FEL) operating in the ultraviolet. An 800 nm seed from a Ti:sapphire laser has been used to produce saturated amplified radiation at the 266 nm third harmonic. The results confirm the predictions for HGHG FEL operation: stable central wavelength, narrow bandwidth, and small pulse-energy fluctuation.
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We report on an experimental investigation characterizing the output of a high-gain harmonic-generation (HGHG) free-electron laser (FEL) at saturation. A seed CO2 laser at a wavelength of 10.6 microm was used to generate amplified FEL output at 5.3 microm. Measurement of the frequency spectrum, pulse duration, and correlation length of the 5.3 microm output verified that the light is longitudinally coherent. Investigation of the electron energy distribution and output harmonic energies provides evidence for saturated HGHG FEL operation.
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A high-gain harmonic-generation free-electron laser is demonstrated. Our approach uses a laser-seeded free-electron laser to produce amplified, longitudinally coherent, Fourier transform-limited output at a harmonic of the seed laser. A seed carbon dioxide laser at a wavelength of 10.6 micrometers produced saturated, amplified free-electron laser output at the second-harmonic wavelength, 5.3 micrometers. The experiment verifies the theoretical foundation for the technique and prepares the way for the application of this technique in the vacuum ultraviolet region of the spectrum, with the ultimate goal of extending the approach to provide an intense, highly coherent source of hard x-rays.
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A short-period in-vacuum undulator for the NSLS X-ray Ring has been developed in a collaboration between SPring-8 and the NSLS, and has achieved its project design goals during commissioning studies. The device is called IVUN (in-vacuum undulator) and employs magnet arrays (31 periods, with an 11 mm period) developed at SPring-8, while the requisite vacuum chamber and mechanical systems were developed at the NSLS. At a magnet gap of 3.3 mm, IVUN produces 4.6 keV radiation in the fundamental, with useful photon fluxes in both the second and third harmonics. The magnet gap is adjustable between 2 and 10 mm. A brief overview of IVUN is presented, together with initial commissioning results: the dependence of electron-beam lifetime and bremsstrahlung on magnet gap, and the output radiation spectrum.
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Forty prelingually deaf high school students were asked to define words from the 1981 Peabody Picture Vocabulary Test (PPVT). The students then ranked the words they had missed in terms of the difficulty they would expect to have in picking out a picture of the word; that is, they were asked to judge their "feeling of knowing" for the missed words. The PPVT was then given to the students and served as a measure of accuracy for their rank-order judgments. Two comparison groups were established: one was a group of hearing adolescents of the same age as the deaf students, and the second was a group of hearing students of the same reading level as the deaf students. The deaf students were unable to judge their feeling of knowing, but both hearing groups were able to do so.
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Cognición , Sordera/psicología , Vocabulario , Adolescente , Adulto , Niño , Humanos , MemoriaRESUMEN
An undulator-based beamline was built and commissioned at the National Synchrotron Light Source to provide tunable coherent radiation in the 200-800 eV range. The low emittance of the storage ring means that the undulator source has high brightness so that a large flux of coherent x rays is delivered to experimental stations. The beamline uses a horizontally dispersing bichromator that allows two experiments to run simultaneously, making use of the first and second harmonics of the undulator output. In addition, the use of horizontally deflecting optics enables the beamline alignment to be insensitive to electron beam motion since the horizontal electron beam size is quite large. The beamline and its performance are discussed with emphasis on the optics and on stability, radiation, and vacuum considerations.
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An infant girl was referred for thyroid screening. The T4 value was 5.0 micrograms/dl (normal 5.0-13.0 micrograms/dl), and the thyroid-stimulating hormone-radioimmunoassay value was greater than 60.0 microIU/ml (normal 0-10.0 microIU/ml). Imaging failed to demonstrate thyroid tissue in the normal anatomic position in the neck. A focal collection of activity was seen, however, on a scan corresponding to the position of the base of the tongue. The finding is consistent with the diagnosis of a lingual (undescended) thyroid.
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Coristoma/diagnóstico por imagen , Hipotiroidismo Congénito , Glándula Tiroides , Femenino , Humanos , Lactante , Cintigrafía , Neoplasias de la Lengua/diagnóstico por imagenRESUMEN
The present study aimed to investigate simultaneously fine orientation discrimination and shape constancy in young infants. The design employed two variants of the habituation paradigm. Infants in one group were habituated to a single orientation (5 or 15 degrees) of a single stimulus presented repeatedly, and they were then tested with the complementary orientation (15 or 5 degrees). Infants in a second group were habituated to several orientations (5, 10, and 15 degrees) of the same stimulus, and they were then tested with a familiar orientation of the stimulus, with two novel orientations of the same stimulus, and with a new stimulus. Between-groups comparison showed that infants habituated more efficiently to re-presentations of a single orientation than to multiple orientations of the same stimulus, providing evidence of fine orientation discrimination; posthabituation comparison within the single-orientation group confirmed that infants discriminated small orientation changes. Posthabituation comparison within the multiple-orientation group showed that infants generalized over novel orientation changes of the familiar stimulus though they discriminated change to a novel stimulus. Cumulatively, the results of this study demonstrate that under one set of conditions young infants show sensitivity to relatively fine variations in pattern orientation, but that under a different set of conditions young infants give evidence of shape constancy with the same patterns.
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Aprendizaje Discriminativo , Percepción de Forma , Orientación , Psicología Infantil , Femenino , Habituación Psicofisiológica , Humanos , Lactante , Masculino , Disposición en PsicologíaRESUMEN
Four experiments were conducted to assess converging aspects of 4-month-old infants' perception of symmetry in visual patterns. Experiments 1 and 2 manipulated the structure and orientation of comparable patterns in order to evaluate the specialty of vertical symmetry. Infants showed no preference among vertically symmetrical, vertically repeated, and obliquely symmetrical patterns, but they processed vertically symmetrical patterns more efficiently than either vertically repeated patterns or obliquely symmetrical patterns. Experiment 3 manipulated the spatial separation of pattern components in order to determine the ability of young infants to integrate and coalesce information in visual patterns that is distributed in space. Infants processed vertically symmetrical patterns whose components were contiguous or nearly contiguous about the vertical axis (0 to 2.5 degrees separations) more efficiently than discontiguous patterns (5 and 10 degrees separations). Thus, extreme spatial separation about the vertical meridian caused infants to lose the advantage for vertical symmetry, and by inference their holistic perception of the visual pattern. Experiment 4 manipulated the organization of individual components of a vertical pattern in order to examine further infants' sensitivity to perceptual organization and synthesis of pattern form. Infants discriminated vertically symmetrical patterns from asymmetrical patterns with a vertical organization, thereby demonstrating sensitivity to the symmetrical organization of the pattern above their perception of components in the pattern. The results of these four experiments together corroborate and extend previous findings that vertical symmetry has a special status in early perceptual development and that infants can perceive pattern wholes.