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1.
Acta Psychiatr Scand ; 132(4): 244-56, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26038817

RESUMEN

OBJECTIVE: Psychosocial trauma during childhood is associated with schizophrenia vulnerability. The pattern of grey matter decrease is similar to brain alterations seen in schizophrenia. Our objective was to explore the links between childhood trauma, brain morphology and schizophrenia symptoms. METHOD: Twenty-one patients with schizophrenia stabilized with atypical antipsychotic monotherapy and 30 healthy control subjects completed the study. Anatomical MRI images were analysed using optimized voxel-based morphometry (VBM). Childhood trauma was assessed with the Childhood Trauma Questionnaire, and symptoms were rated on the Scale for the Assessment of Negative Symptoms (SANS) and Scale for the Assessment of Positive Symptoms (SAPS) (disorganization, positive and negative symptoms). In the schizophrenia group, we used structural equation modelling in a path analysis. RESULTS: Total grey matter volume was negatively associated with emotional neglect (EN) in patients with schizophrenia. Whole-brain VBM analyses of grey matter in the schizophrenia group revealed a specific inversed association between EN and the right dorsolateral prefrontal cortex (DLPFC). Path analyses identified a well-fitted model in which EN predicted grey matter density in DLPFC, which in turn predicted the disorganization score. CONCLUSION: Our findings suggest that EN during childhood could have an impact on psychopathology in schizophrenia, which would be mediated by developmental effects on brain regions such as the DLPFC.


Asunto(s)
Maltrato a los Niños/psicología , Sustancia Gris/patología , Corteza Prefrontal/patología , Esquizofrenia Infantil/patología , Esquizofrenia Hebefrénica/patología , Adulto , Mapeo Encefálico , Estudios de Casos y Controles , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Masculino , Valor Predictivo de las Pruebas , Psicología , Psicología del Esquizofrénico
2.
Appl Opt ; 53(12): 2646-55, 2014 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-24787591

RESUMEN

We report on 400 nm broadband type I frequency doubling in a noncollinear geometry with pulse-front-tilted and chirped femtosecond pulses (λ =800 nm; Fourier transform limited pulse duration, 45 fs). With moderate power densities (2 to 10 GW/cm2) thus avoiding higher-order nonlinear phenomena, the energy conversion efficiency was up to 65%. Second-harmonic pulses of Fourier transform limited pulse duration shorter than the fundamental wave were generated, exhibiting good beam quality and no pulse-front tilt. High energy (20 mJ/pulse) was produced in a 40 mm diameter and 6 mm thick LBO crystal. To the best of our knowledge, this is the first demonstration of this optical configuration with sub-100-fs pulses. Good agreement between experimental results and simulations is obtained.

3.
Opt Express ; 21(21): 25248-56, 2013 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-24150365

RESUMEN

In this work we demonstrate the development of a complete analog feedback loop for the control of the carrier-envelope phase (CEP) of a high-average power (20 W) laser operating at 10 kHz repetition rate. The proposed method combines a detection scheme working on a single-shot basis at the full-repetition-rate of the laser system with a fast actuator based either on an acousto-optic or on an electro-optic crystal. The feedback loop is used to correct the CEP fluctuations introduced by the amplification process demonstrating a CEP residual noise of 320 mrad measured on a single-shot basis. The comparison with a feedback loop operating at a lower sampling rate indicates an improvement up to 45% in the residual noise. The measurement of the CEP drift for different integration times clearly evidences the importance of the single-shot characterization of the residual CEP drift. The demonstrated scheme could be efficiently applied for systems approaching the 100 kHz repetition rate regime.

4.
Opt Express ; 19(21): 19935-41, 2011 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-21997002

RESUMEN

Using an original CEP stabilization technique based on the linear electro-optical effect in a specific crystal, we achieved long term CEP stabilization of a 20 W, 1 kHz laser with residual noise as low as 440 mrad (rms). At 3 W, the CEP shot to shot noise is kept as low as 320 mrad (rms) over half an hour.

5.
Opt Express ; 19(6): 5410-8, 2011 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-21445180

RESUMEN

We present a new method to control the Carrier-Envelope Phase of ultra-short laser pulses by using the linear Electro-Optic Effect. Experimental demonstration is carried out on a Chirped Pulse Amplification based laser. Phase shifts greater than π radian can be obtained by applying moderate voltage on a LiNbO3 crystal with practically no changes to all other parameters of the pulse with the exception of its group delay. Time response of the Electro-Optic effect makes possible shaping at a high repetition rate or stabilization of the CEP of ultra short CPA laser systems.

6.
Rev Chilena Infectol ; 26(3): 270-2, 2009 Jun.
Artículo en Español | MEDLINE | ID: mdl-19621163

RESUMEN

Myiasis is a parasitic infestation of human or animal skin, necrotic tissues and natural cavities by fly larvae or pupa. In this paper we will describe the case of a 27 years old woman, asymptomatic, that spontaneously eliminated from her vagina two Eristalis tenax larvae, a worldwide distributed fly specie, classified as an accidental myiasis agent. The patient lived in an urban area, she had low socioeconomic status and she had the antecedent record of use of intravaginal vegetables as sexual stimulator. Analyzing the case and the references, we concluded the patient had an accidental infestation by E. tenax, being the vaginal introduction of vegetables the most probable mechanism of transmission. This kind of infestation has not been communicated in the literature. Also, this is the first documented case of E. tenax myiasis in Chile.


Asunto(s)
Dípteros/clasificación , Miasis/parasitología , Vagina/parasitología , Adulto , Animales , Femenino , Humanos , Larva/clasificación , Miasis/diagnóstico
7.
Rev. chil. infectol ; 26(3): 270-272, jun. 2009. ilus, tab
Artículo en Español | LILACS | ID: lil-518466

RESUMEN

Myiasis is a parasitic infestation of human or animal skin, necrotic tissues and natural cavities by fly larvae or pupa. In this paper we will describe the case of a 27 years oíd woman, asymptomatic, that spontaneously eliminated from her vagina two Eristalis tenax larvae, a worldwide distributed fly specie, classified as an accidental myiasis agent. The patient lived in an urban área, she had low socioeconomic status and she had the antecedent record of use of intravaginal vegetables as sexual stimulator. Analyzing the case and the references, we concluded the patient had an accidental infestation by E. tenax, being the vaginal introduction of vegetables the most probable mechanism of transmission. This kind of infestation has not been communicated in the literature. Also, this is the first documented case of E. tenax myiasis in Chile.


Las miasis son infestaciones parasitarias de humanos o animales por larvas de mosca que infestan piel, tejidos necróticos y cavidades naturales. Presentamos el caso de una mujer de 27 años, asintomática, que eliminó espontáneamente por vía vaginal larvas de Eristalis tenax, una especie de mosca ampliamente distribuida en el mundo, la que es clasificada como agente de miasis accidental. La paciente residía en un área urbana de nivel socioeconómico bajo y entregaba como antecedente el uso de vegetales intravaginales como estimulante sexual. Analizando el caso descrito y la bibliografía existente, concluimos que la paciente presentó una infestación accidental por E. tenax, siendo el mecanismo más probable de transmisión la introducción vaginal de vegetales. Este mecanismo no ha sido comunicado previamente en la literatura. Además, este es el primer caso de miasis por E. tenax documentado en Chile.


Asunto(s)
Adulto , Animales , Femenino , Humanos , Dípteros/clasificación , Miasis/parasitología , Vagina/parasitología , Larva/clasificación , Miasis/diagnóstico
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