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We describe the design and alignment of an unobscured reflective image relay for use in an ultra-broadband half-petawatt laser system in development at the University of Rochester's Laboratory for Laser Energetics. The design consists of four spherical mirrors in an unobscured configuration. We show the theoretical basis for such a four-mirror design using first-order optical matrix methods and nodal aberration theory. We also describe the process of aligning this design in a test bed and show the results of this alignment method. We were able to achieve a diffraction-limited nominal design. Upon aligning the design in our test bed, we were able to successfully align the design to achieve our target wavefront error of less than 0.3 waves peak to valley and 0.07 waves rms at the central laser-operating wavelength of 910 nm.
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The validity of cross-cultural comparisons of test scores requires that scores have the same meaning across cultures, which is usually tested by checking the invariance of the measurement model across groups. In the last decade, a large number of studies were conducted to verify the equivalence across cultures of the dimensional Alternative Model of Personality Disorders (DSM-5 Section III). These studies have provided information on configural invariance (i.e., the facets that compose the domains are the same) and metric invariance (i.e., facet-domain relationships are equal across groups), but not on the stricter scalar invariance (i.e., the baseline levels of the facets are the same), which is a prerequisite for meaningfully comparing group means. The present study aims to address this gap. The Personality Inventory for DSM-5 (PID-5) was administered to five samples differing on country and language (Belgium, Catalonia, France, Spain, and Switzerland), with a total of 4,380 participants. Configural and metric invariance were supported, denoting that the model structure was stable across samples. Partial scalar invariance was supported, being minimal the influence of non-invariant facets. This allowed cross-cultural mean comparisons. Results are discussed in light of the sample composition and a possible impact of culture on development of psychopathology.
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Comparação Transcultural , Transtornos da Personalidade , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Transtornos da Personalidade/diagnóstico , Inventário de Personalidade , Psicometria , Reprodutibilidade dos TestesRESUMO
A primary limitation of optical coherence microscopy is the lack of sufficient lateral resolution over a usable imaging volume for diagnostic applications, even with high-numerical aperture imaging optics. In this paper, we first motivate the benefit of refocusing at multiple depths in a highly scattering biological sample using optical coherence microscopy, which experimentally shows invariant 2.5 mum axial and 6.5 mum lateral resolution throughout the sample. We then present the optical system design of a hand-held probe with the advanced capability to dynamically focus with no moving parts to a depth of 2 mm in skin-equivalent tissue at 3 mum resolution throughout an 8 cubic millimeter imaging volume. The built-in dynamic focusing ability is investigated with an addressable liquid crystal lens embedded in a custom-designed optics optimized for a Ti:Sa pulsed broadband laser source of bandwidth 100nm centered at 800nm. The design was developed not only to account for refocusing into the tissue but also to minimize and compensate for the varying on-axis and off-axis optical aberrations that would be introduced throughout a 2 mm thick and 2 mm wide skin imaging volume. The MTF contrast functions and distortion plots at three different skin depths are presented.
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BACKGROUND: This paper reports the first validation study of the EPN-31 scale (Positive and Negative Emotionality scale, 31 items) in a French psychiatric sample. This questionnaire has been adapted by Rolland from an emotion inventory developed by Diener, and is also in accordance with Watson and Clark's tripartite model of affects. METHODOLOGICAL ASPECTS: Respondents were asked to rate the frequency with which they had experienced each affect (31 basic emotional states) during the last month. The answer format was a 7-point scale, ranging from 1 "Not experienced at all" to 7 "Experienced this affect several times each day". Three main scores were calculated (positive affects, negative affects, and surprise affects), as well as six sub-scores (joy, tenderness, anger, fear, sadness, shame). Four hundred psychiatric patients were included in this study, and completed the EPN-31 scale and the Hospital Anxiety and Depression (HAD) scale. The Global Assessment of Functioning (GAF) scale was rated, as well as DSM IV diagnostic criteria. We performed a principal component analysis, with Varimax orthogonal transformation, and explored the factorial structure of the questionnaire, the internal consistency of each dimension, and the correlations between EPN-31 scores and HAD scores. RESULTS: The factorial structure of the EPN-31 was well-defined as expected, with a three-factor (positive, negative and surprise affects) solution accounting for 58.2% of the variance of the questionnaire. No correlation was obtained between positive and negative affects EPN-31 scores (r=0.006). All alpha Cronbach coefficients were between 0.80 and 0.95 for main scores, and between 0.72 and 0.90 for sub-scores. GAF scores were significantly correlated with EPN-31 positive affects scores (r=0.21; p=0.001) and with EPN-31 negative affects scores (r=- 0.45; p=0.001). We obtained significant correlations between positive affects score and HAD depression score (r=- 0.45; p<0.001), and between negative affects score and HAD anxiety (r=0.56; p<0.001) and depression (r=0.45; p<0.001) scores. This pattern of correlation was in accordance with the Watson tripartite model of emotionality. Significantly higher EPN-31 positive affect mean scores were observed in females when compared to males (p<0.001). The third factor of the EPN-31 is less robust than the others and, the validity of the surprise score could hence be discussed. CONCLUSION: In all, this study confirmed the validity and the interest of the EPN-31 use in psychiatric patients. Various clinical and research applications can be considered, such as infra-symptomatic studies of emotions in affective disorders and during treatment protocols or definition of phenotypic markers in genetic or neuro-imagery studies.
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Afeto , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos TestesRESUMO
We describe a cognitive rehabilitation mixed-reality system that allows therapists to explore natural cuing, contextualization, and theoretical aspects of cognitive retraining, including transfer of training. The Human Experience Modeler (HEM) mixed-reality environment allows for a contextualized learning experience with the advantages of controlled stimuli, experience capture and feedback that would not be feasible in a traditional rehabilitation setting. A pilot study for testing the integrated components of the HEM is discussed where the participant presents with working memory impairments due to an aneurysm.
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Atividades Cotidianas , Dano Encefálico Crônico/reabilitação , Simulação por Computador , Transtornos da Memória/reabilitação , Transferência de Experiência , Interface Usuário-Computador , Dano Encefálico Crônico/complicações , Dano Encefálico Crônico/fisiopatologia , Meio Ambiente , Lobo Frontal/fisiopatologia , Humanos , Aneurisma Intracraniano/complicações , Masculino , Transtornos da Memória/etiologia , Transtornos da Memória/fisiopatologia , Pessoa de Meia-Idade , Projetos PilotoRESUMO
A compact and low-cost detection electronics scheme for optical coherence imaging is demonstrated. The performance of the designed electronics is analyzed in comparison to a commercial lock-in amplifier of equal bandwidth. Images of a fresh-onion sample are presented for each detection configuration.
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Freeze-fracture has been used to examine perfluorodecalin/egg yolk phospholipid emulsions (70:8, w/v%) destined to be used as injectable oxygen carriers. The fluorocarbon displays a specific granular aspect upon freeze-fracture which makes it readily recognizable and allows the distinction between two populations of objects on the micrographs: fluorocarbon droplets and water-filled lipid vesicles.
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Fluorocarbonos/química , Gema de Ovo , Emulsões , Técnica de Fratura por Congelamento , Microscopia Eletrônica , Fosfolipídeos/químicaRESUMO
The area over which boundary information contributes to the determination of the center of an extended object was inferred from results of a bisection task. The object to be bisected was a rectangle with two long sinusoidally modulated sides, i.e. a wiggly rectangle. The spatial frequency and amplitude of the edge modulation were varied. Two object widths were tested. The modulation of the perceived center approximately equaled that of the edges at very low edge modulation frequencies and decreased in amplitude with increasing edge modulation frequency. The edge modulation had a greater modulating effect on the perceived center for the narrower object than for the wider object. This scaling with object width didn't follow perfect zoom invariance but was precisely matched by the scaling of the bisection threshold with width, strongly supporting the idea that the same mechanism determines both the location of the perceived center for these stimuli and its variance. We propose that this mechanism is the linking of object boundaries at a scale determined by the object width.
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Percepção de Forma/fisiologia , Percepção de Tamanho/fisiologia , Humanos , Julgamento , Limiar Sensorial/fisiologiaRESUMO
Surface pressure-area isotherms of a series of fluorinated DFnCmPC phosphatidylcholines bearing two acyl chains ended by a perfluoroalkyl Fn tail of variable lengths were recorded at the air-water interface. The limiting molecular areas (Ax), the collapse pressures (pi c), the pressures of the liquid-expanded to liquid-condensed phase transition (pi t) and their associated Ac and At areas were deduced from these experiments and compared to those of their hydrocarbon DMPC, DPPC and DSPC analogs. The impact of the fluorinated tails on the characteristics of phosphatidylcholine monolayers, as well as the dependence of the observed effects on the length of these tails and their relative weight with respect to the whole hydrophobic chain length, i.e. the degree of 'fluorination' of the monolayer, is interpreted in terms of steric hindrance, hydrophobicity and chain-chain interaction balance.
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Compostos de Flúor/química , Fosfatidilcolinas/química , Fenômenos Químicos , Química , Estrutura Molecular , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Propriedades de SuperfícieRESUMO
This paper describes the morphological characterization, by freeze-fracture electron microscopy, and the thermotropic phase behavior, by differential scanning calorimetry and/or X-ray scattering, of aqueous dispersions of various hydroxylated and galactosylated double-chain amphiphiles and bolaamphiphiles, several of them containing one or two hydrophobic fluorocarbon chains. Colloidal systems are observed in water with the hydroxylated hydrocarbon or fluorocarbon bolaamphiphiles only when they are dispersed with a co-amphiphile such as rac-1,2-dimyristoylphosphatidylcholine (DMPC) or rac-1,2-distearoylphosphatidylcholine (DSPC). Liposomes are formed providing the relative content of bolaamphiphiles does not exceed 20% mol. Most of these liposomes can be thermally sterilized and stored at room temperature for several months without any significant modification of their size and size distribution. The hydrocarbon galactosylated bolaamphiphile HO[C24][C12]Gal forms in water a lamellar phase (the gel to liquid-crystal phase transition is complete at 45 degrees C) and a Im3m cubic phase above 47 degrees C. The fluorocarbon HO[C24][F6C5]Gal analog displays a more complex and metastable phase behavior. The fluorinated non-bolaform galactosylated [F8C7][C16]AEGal and SerGal amphiphiles form lamellar phases in water. Low amounts (10% molar ratio) of the HO[C24][F6C5]Gal or HO[C24][C12]Gal bolaamphiphiles or of the single-headed [F8C7][C16]AEGal improve substantially the shelf-stability of reference phospholipon/cholesterol 2/1 liposomes. These liposomes when co-formulated with a single-headed amphiphile from the SerGal series are by far less stable.
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Dimiristoilfosfatidilcolina/química , Portadores de Fármacos/química , Lipossomos/química , Fosfatidilcolinas/química , Varredura Diferencial de Calorimetria , Fluorocarbonos/química , Técnica de Fratura por Congelamento , Galactose/química , Hidrocarbonetos/química , Microscopia Eletrônica , Espalhamento de RadiaçãoRESUMO
The ideal observer represents a Bayesian approach to performing detection tasks. Since such tasks are frequently used as a prototype tasks for radiological imaging systems, the detectability measured at the output of an ideal detector can be used as a figure of merit to characterize the imaging system. For the detectability achieved by the ideal observer to be a good figure of merit, it should predict the ability of the human observer to perform the same detection task. Of great general interest, especially to the medical community, are imaging devices with long-tailed point spread functions (PSFs). Such PSFs may occur due to septal penetration in collimators, veiling glare in image intensifiers or scattered radiation in the body. We have investigated the effect that this type of PSF has on human visual signal detection and whether any improvement in performance can be gained by deconvolving the tails of the PSF. For the ideal observer, it is straightforward to show that the performance is independent of any linear, invertible deconvolution filter. Our psychophysical studies show, however, that performance of the human observer is indeed improved by deconvolution. The ideal observer is, therefore, not a good predictor of human observer performance for detection of a signal imaged through a long-tailed PSF. We offer some explanations for this discrepancy by using some characteristics of the visual process and suggest a standard of comparison for the human observer that takes into account these characteristics. A look at the performance of the non-prewhitening (npw) ideal observer, before and after deconvolution, also brings some good insight into this study.
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Teorema de Bayes , Diagnóstico por Imagem/normas , Variações Dependentes do Observador , HumanosRESUMO
We introduced a slight modification of Unicryl for fast polymerization at low temperature (in the range-20 degree C to-35 degree C) without modification of both physical properties and immunocytochemical yield. An UV initiator benzoin ethyl ether (BEE) is added at 0.05% concentration in neat resin during infiltration and final polymerization at-35 degree C. Immunogold labeling of amylase of mouse pancreas embedded in standard conditions recommended by the manufacturer or with our modification were compared by counting colloidal gold particles over zymogen granules using MACS, a specialized software dedicated to this operation. We noticed that addition of 0.05% BEE in Unicryl reduces the curing time to 16 h, which can be extended up to a maximum of 48 h at-35 degree C without noticeable modification of ultrastructural morphology, physical properties and immunocytochemical yield.
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Resinas Acrílicas/química , Microscopia Imunoeletrônica/métodos , Inclusão em Plástico/métodos , Animais , Benzoína/análogos & derivados , Temperatura Baixa , Etil-Éteres , Imuno-Histoquímica/métodos , Camundongos , Pâncreas/ultraestrutura , Sensibilidade e Especificidade , SoftwareRESUMO
The suitability of the Revised NEO Personality Inventory (NEO PI-R) to assess adolescents' personality traits was investigated in an unselected heterogeneous sample of 469 adolescents aged 12 to 17 years. They were further administered the Hierarchical Personality Inventory for Children (HiPIC) to allow an examination of convergent and discriminant validity. The adult NEO PI-R factor structure proved to be highly replicable in the sample of adolescents, with all facet scales primarily loading on the expected factors, independent of the age group. Domain and facet internal consistency coefficients were comparable to those obtained in adult samples, with less than 12% of the items showing corrected item-facet correlations below absolute value .20. Although, in general, adolescents reported few difficulties with the comprehensibility of the items, they tend to report more problems with the Openness to Ideas (05) and Openness to Values (06) items. Correlations between NEO PI-R and HiPIC scales underscored the convergent and discriminant validity of the NEO facets and HiPIC scales. It was concluded that the NEO PI-R in its present form is useful for assessing adolescents' traits at the primary level, but additional research is necessary to infer the most appropriate facet level structure.
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Inventário de Personalidade , Personalidade , Psicologia do Adolescente , Adolescente , Adulto , Bélgica , Criança , Análise Fatorial , Feminino , Humanos , Masculino , Teoria Psicológica , Psicometria , Reprodutibilidade dos TestesRESUMO
The authors describe simple and rapid separation technics by electrophoresis on cellulose acetate of glucose-6-phosphate dehydrogenase isoenzymes, 6-phosphogluconate dehydrogenase, phosphoglucomutase, adenosine deaminase, adenylate kinase, phosphohexose isomerase, lactate dehydrogenase iosenzymes in the red cells. These technics are derived from those of Rattazi et al. for glucose-6-phosphate dehydrogenase and Sonneborn for 6-phosphogluconate dehycrogenase, phosphoglucomutase, adenosine deaminase, adenylate kinase and acid phosphatase.
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Eritrócitos/enzimologia , Isoenzimas/sangue , Fosfatase Ácida/sangue , Adenosina Desaminase/sangue , Adenilato Quinase/sangue , Eletroforese em Acetato de Celulose , Glucose-6-Fosfato Isomerase/sangue , Glucosefosfato Desidrogenase/sangue , Humanos , L-Lactato Desidrogenase/sangue , Fenótipo , Fosfoglucomutase/sangue , Fosfogluconato Desidrogenase/sangueRESUMO
Modern surgeons have at their disposal a vast array of advanced technological data dissemination devices. The ring of high resolution monitors circling the typical operating area to display pre-operative and real-time patient data is esteemly supportive. The drawback, however, is that such displays require the surgeons to frequently shift their head and gaze away from the principle field of interest. We describe a new display technique that provides surgeons with a lightweight, wearable display surface that permits localization of medical data of main interest near the field of operation with minimal head and gaze movements.
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Apresentação de Dados , Aumento da Imagem/instrumentação , Equipamentos Cirúrgicos , Desenho de Equipamento , Movimentos da Cabeça , Humanos , Óptica e FotônicaRESUMO
We propose in this paper a novel method for the modeling of the motion of anatomical joints. The method is based on collision detection and knowledge of biomedical experimental data.
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Processamento de Imagem Assistida por Computador , Articulação do Joelho/fisiologia , Modelos Anatômicos , Instrução por Computador , Educação de Graduação em Medicina , Humanos , Movimento/fisiologia , Amplitude de Movimento ArticularRESUMO
A system for automatic modeling of anatomical joint motion for use in the Virtual Reality Dynamic Anatomic (VRDA) tool is described. The modeling method described in this article relies on collision detection. An original incremental algorithm use this information to achieve stable positions and orientations of the tibia on the femur for each angle considered between these two components on the range of motion. The stable states then become the basis for a look-up table employed in the animation of the motion of the joint. The strength of the method lies in its robustness to animate any "normal" anatomical joint, given a set of kinematic constraints for the joint type as well as an accurate 3D geometric model of the joint. The demonstration could be patient specific (based on a person's real anatomical data from an imaging procedure such as CT scanning) or scaled from a generic joint based on external patient measurements. The modeling method has been implemented on a generic knee model for use in the VRDA tool.
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Simulação por Computador , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/fisiologia , Modelos Anatômicos , Algoritmos , Fenômenos Biomecânicos , HumanosRESUMO
Using augmented reality (AR) to teach dynamic 3-D anatomy may impart better understanding of bone dynamics during body movement. We are currently developing an AR tool that will allow superimposition and registration of bone structures on real anatomical counterparts of a human subject. This article describes the application, the problems to be solved, and reports on preliminary developmental studies of a first prototype of the tool. Specifically, studies test approaches to simulating real-time dynamic anatomy, and the feasibility in achieving registration of 3-D anatomical bones on their real counterparts. Such a tool will offer several unique advantages over traditional teaching methods and overcome many of their current limitations.
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Anatomia/educação , Simulação por Computador , Processamento de Sinais Assistido por Computador , Interface Usuário-Computador , Calibragem , Humanos , Articulações/anatomia & histologiaRESUMO
The aim of the present study was to show differences between culture-bound stress levels in two samples of elementary and junior high school teachers in Italy (N = 299) and in France (N = 217), using the Maslach Burnout Inventory (MBI; Maslach & Jackson, 1981) as a questionnaire. The results confirmed the influence of sociocultural background on stress levels in both samples in relation to age. Personal accomplishment was the most discriminating indicator in the two groups.
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Esgotamento Profissional , Ensino , Adulto , Fatores Etários , Comparação Transcultural , Cultura , Feminino , França , Humanos , Itália , Masculino , Instituições Acadêmicas , Autoimagem , Fatores Sexuais , Estresse Psicológico/psicologiaRESUMO
The authors report a new case of carotid body tumour operated on, in a 26 year old woman. Recalling the main clinical and histological characteristics of these tumours, they emphasize the importance of pre-operative assessment and the decisive value of arteriography. Modern techniques of surgery of the carotid bodies permit one to face the risk of damage during removal. They re-emphasize the necessity of surgical treatment able to ensure a cure. Finally, emphasizeing the special gravity of advanced tumours (group III), they condemn a conservative attitude and recommended operation as early as possible.