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1.
PLoS One ; 19(6): e0304272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38843210

RESUMO

Dementia can disrupt how people experience and describe events as well as their own role in them. Alzheimer's disease (AD) compromises the processing of entities expressed by nouns, while behavioral variant frontotemporal dementia (bvFTD) entails a depersonalized perspective with increased third-person references. Yet, no study has examined whether these patterns can be captured in connected speech via natural language processing tools. To tackle such gaps, we asked 96 participants (32 AD patients, 32 bvFTD patients, 32 healthy controls) to narrate a typical day of their lives and calculated the proportion of nouns, verbs, and first- or third-person markers (via part-of-speech and morphological tagging). We also extracted objective properties (frequency, phonological neighborhood, length, semantic variability) from each content word. In our main study (with 21 AD patients, 21 bvFTD patients, and 21 healthy controls), we used inferential statistics and machine learning for group-level and subject-level discrimination. The above linguistic features were correlated with patients' scores in tests of general cognitive status and executive functions. We found that, compared with HCs, (i) AD (but not bvFTD) patients produced significantly fewer nouns, (ii) bvFTD (but not AD) patients used significantly more third-person markers, and (iii) both patient groups produced more frequent words. Machine learning analyses showed that these features identified individuals with AD and bvFTD (AUC = 0.71). A generalizability test, with a model trained on the entire main study sample and tested on hold-out samples (11 AD patients, 11 bvFTD patients, 11 healthy controls), showed even better performance, with AUCs of 0.76 and 0.83 for AD and bvFTD, respectively. No linguistic feature was significantly correlated with cognitive test scores in either patient group. These results suggest that specific cognitive traits of each disorder can be captured automatically in connected speech, favoring interpretability for enhanced syndrome characterization, diagnosis, and monitoring.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Fala , Humanos , Demência Frontotemporal/psicologia , Demência Frontotemporal/diagnóstico , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Estudos de Casos e Controles , Biomarcadores , Processamento de Linguagem Natural , Aprendizado de Máquina , Testes Neuropsicológicos , Função Executiva/fisiologia
3.
Sci Rep ; 8(1): 11263, 2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-30050141

RESUMO

We present an experimental method, based on the use of dynamic split-lens configurations, useful for the trapping and spatial control of microparticles through the photophoretic force. In particular, the concept of split-lens configurations is exploited to experimentally create customized and reconfigurable three-dimensional light structures, in which carbon coated glass microspheres, with sizes in a range of 63-75 µm, can be captured. The generation of light spatial structures is performed by properly addressing phase distributions corresponding to different split-lens configurations onto a spatial light modulator (SLM). The use of an SLM allows a dynamic variation of the light structures geometry just by modifying few control parameters of easy physical interpretation. We provide some examples in video format of particle trapping processes. What is more, we also perform further spatial manipulation, by controlling the spatial position of the particles in the axial direction, demonstrating the generation of reconfigurable three-dimensional photophoretic traps for microscopic manipulation of absorbing particles.

4.
Opt Express ; 25(20): 23773-23783, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-29041328

RESUMO

We report the realization of polarization sensitive split lens configurations. While split lenses can be used to easily generate different types of controlled structured light patterns, their realization has been limited so far to scalar beams. Here we propose and experimentally demonstrate their generalization to vectorial split lenses, leading to light patterns with customized intensity and state of polarization. We demonstrate how these polarization split lenses can be experimentally implemented by means of an optical system using two liquid crystal spatial light modulators, each one phase modulating one orthogonal polarization component. As a result, we demonstrate the experimental generation of vectorial beams with different shapes generated with these dual polarization split lenses. Excellent experimental results are provided in each case. The proposed technique is a simple method to generate structured light beams with polarization diversity, with potential applications in polarimetry, customized illuminators or quantum optics.

5.
J Appl Res Intellect Disabil ; 30(5): 970-974, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27456465

RESUMO

BACKGROUND: Down syndrome (DS) and Fragile X syndrome (FXS) are the major genetic causes of intellectual disabilities. Here, we present a case of a 32-year-old woman with the diagnosis of both FXS and DS. She is the daughter of a 47-year-old pre-mutation woman who also has three sons with FXS. METHODS: Cytogenetic testing detected the presence of a complete trisomy 21. A combination of PCR and Southern blot analysis was utilized to document the presence of the FMR1 full mutation. RESULTS: The patient has physical characteristics and behavioural disturbances typical of both FXS and DS, which were confirmed by molecular testing. Her treatment plan included a trial of sertraline because of the severity of her shyness and lack of language. She had an excellent response to sertraline with improvement in shyness and social interactions, particularly with family members. CONCLUSIONS: In this study, we report the case of a woman with both FXS and DS, which is the fifth case of FXS and DS in the world's literature. The patient is from Ricaurte, a small town in Colombia, South America, where there is the world's highest prevalence for FXS.


Assuntos
Síndrome de Down/fisiopatologia , Síndrome do Cromossomo X Frágil/fisiopatologia , Adulto , Colômbia , Comorbidade , Síndrome de Down/tratamento farmacológico , Síndrome de Down/genética , Feminino , Síndrome do Cromossomo X Frágil/tratamento farmacológico , Síndrome do Cromossomo X Frágil/genética , Humanos
6.
Opt Lett ; 40(16): 3790-3, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26274661

RESUMO

An optical setup able to generate arbitrary states of polarization (SOPs) with customized degree of polarization is presented in this Letter. Compared with the few alternatives existing in literature, it presents an easy-to-build optical setup and leads to a superior performance. In fact, experimental results are presented, providing an accurate control for the generation of SOPs (maximum error of 1.7% and 3.3% for ellipticity and azimuth, respectively) as well as for the associated degree of polarization (full experimental variation from 1 up to 0.003, with a 1.7% maximum error). The system proposed may be useful for different applications, for example, for polarimeters testing, speckle metrology, and biological applications.

7.
Appl Opt ; 53(25): 5585-92, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25321350

RESUMO

A polarimeter architecture is presented based on a birefringent grating displayed onto a parallel-aligned liquid crystal (LC) on silicon display (PAL-LCoS). The system is compact and flexible, since the size of the image can be adjusted by means of the period of the grating. The LCoS grating permits simultaneously measuring two orthogonal states of polarization (SOPs). By adding a wave plate, different couples of orthogonal SOPs can be detected. First, a basic proof of concept is presented using one quarter-wave and one half-wave plate with fixed retardances, which permit measuring the six SOPs classically used in polarimetry (linear states at 0°, 45°, 90°, and 135°, and R and L circular states). Next, the system is made fully programmable by incorporating a variable LC retarder (LCR). The LCR orientation and retardance values are optimized by means of the condition number indicator, in order to provide equivalent optimal accuracy. Experimental results of calibration images and test images are presented, showing the potentials of this architecture.

8.
Rev. chil. obstet. ginecol ; 79(4): 277-282, 2014. tab
Artigo em Espanhol | LILACS | ID: lil-724827

RESUMO

Antecedentes: El síndrome de Turner (ST) es causado por la ausencia total o parcial del cromosoma X y posee una gran variedad en su presentación citogenética. Objetivos: Determinar la variedad de presentación citogenética y la existencia de diferencias entre los casos diagnosticados in útero y los de diagnóstico postnatal, en pacientes con ST en dos laboratorios de referencia de Cali, Colombia. Métodos: Se realizó un estudio observacional descriptivo de corte transversal, se incluyeron pacientes con diagnóstico de ST, cuyo cariotipo se realizó entre los años 2000 y 2012, en los laboratorios de citogenética de la Universidad del Valle y un instituto de genética de Cali, Colombia. Se recolectó información del reporte del cariotipo, tipo de muestra y tiempo de realización del diagnóstico y se determinó frecuencias y asociaciones estadísticas entre las variables a estudiar. Resultados: Se incluyeron 181 pacientes con fórmula cromosómica compatible con ST; 69 fueron diagnosticados in útero, los demás, en recién nacidos vivos, infantes o adultos. La fórmula cromosómica 45 X0 se encontró en el 95,6 por ciento de los casos de diagnóstico prenatal y 58 por ciento de los de diagnóstico postnatal. Se aplicó la prueba del test exacto de Fisher, comparando los múltiples subgrupos de la variedad de presentación citogenética de diagnóstico prenatal y postnatal, encontrándose diferencias estadísticamente significativas en la distribución de las dos poblaciones evaluadas (p<0,001). Conclusiones: Existen diferencias significativas en los cariotipos de los pacientes con ST diagnosticados in útero, respecto a los diagnosticados en vida extrauterina. Se postula que esa diferencia tendría una explicación biológica sobre la posibilidad de muerte in útero por la ausencia total del cromosoma X.


Background: Turner syndrome is caused by the complete or partial absence of chromosome X and has a great variety in their cytogenetic presentation. Objectives: To determine the variety of cytogenetic presentation and the presence of differences between cases diagnosed in uterus and postnatally, in patients with Turner syndrome at two reference laboratories of Cali, Colombia. Methods: A descriptive cross-sectional study was performed. We included patients with cytogenetic diagnosis of Turner syndrome performed between 2000 and 2012 at cytogenetic laboratories of Universidad del Valle and a genetic institute in Cali, Colombia. The information of karyotype result, type of sample and the diagnosis moment was collected, determining frequencies and statistical associations. Results: 181 patients with Turner's chromosomic presentation; 69 were diagnosed in uterus, the other as live newborns, infants or adults. Chromosomal formula 45X0 was found in 95.6 percent of cases with prenatal diagnosis and 58 percent of postnatal diagnosis. Fisher's test was applied, comparing the cytogenetic presentations of prenatal and postnatal diagnosis, statistically significant difference in the distribution of the two populations evaluated was found (p<0.001). Conclusions: There are significant differences in the karyotypes of patients with ST diagnosed in utero, compared to those diagnosed in postnatal life. We hypothesize that this difference would have a biological explanation due to a higher probability of death in utero by the complete absence of chromosome X.


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Análise Citogenética , Síndrome de Turner/diagnóstico , Síndrome de Turner/genética , Colômbia , Estudos Transversais , Epidemiologia Descritiva
9.
Rev. colomb. cardiol ; 20(6): 406-409, nov.-dic. 2013. ilus
Artigo em Espanhol | LILACS, COLNAL | ID: lil-706573

RESUMO

La comunicación interventricular es una de las complicaciones mecánicas posteriores al infarto agudo del miocardio que genera alta morbilidad y mortalidad. Luego del uso de trombolíticos esta complicación ha disminuido y ha hecho que esta entidad sea cada vez menos frecuente. En este artículo se expone el caso de un paciente con síndrome coronario agudo sin terapia de reperfusión inicial, con posterior ruptura del septum interventricular, en quien se evidenció la utilidad de la ecocardiografía en el diagnóstico de dicha entidad.


Interventricular communication is a one of the mechanical complications after acute myocardial infarction that generates high morbidity and mortality. After the use of thrombolytics this complication has decreased and has made it increasingly less frequent. This article presents the case of a patient with acute coronary syndrome without initial reperfusion therapy, with subsequent rupture of the interventricular septum, in whom the use of echocardiography in the diagnosis of this entity evidenced its usefulness.


Assuntos
Humanos , Masculino , Idoso , Infarto do Miocárdio , Ecocardiografia , Comunicação Interventricular
10.
Buenos Aires; Instituto Universitario de Ciencias de la Salud - Fund. H. A. Barcelo; 1998. 10 p. ilus.
Monografia em Espanhol | BINACIS | ID: biblio-1190603
11.
Buenos Aires; Instituto Universitario de Ciencias de la Salud - Fund. H. A. Barcelo; 1998. 10 p. ilus. (62922).
Monografia em Espanhol | BINACIS | ID: bin-62922
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