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1.
Psychiatry Res ; 304: 114134, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34358762

RESUMO

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.


Assuntos
Comparação Transcultural , Transtornos da Personalidade , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Transtornos da Personalidade/diagnóstico , Inventário de Personalidade , Psicometria , Reprodutibilidade dos Testes
2.
Appl Opt ; 58(35): 9514-9523, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31873549

RESUMO

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.

3.
Virology ; 404(2): 215-24, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20627352

RESUMO

Among a panel of 788 clinical influenza H3N2 isolates, two isolates were characterized by an oseltamivir-resistant phenotype linked to the absence of any detectable NA activity. Here, we established that the two H3NA- isolates lack any detectable full-length NA segment, and one of these could be rescued by reverse genetics in the absence of any NA segment sequence. We found that the absence of NA segment induced a moderate growth defect of the H3NA- viruses as on cultured cells. The glycoproteins density at the surface of H3NA- virions was unchanged as compared to H3N2 virions. The HA protein as well as residues 188 and 617 of the PB1 protein were shown to be strong determinants of the ability of H3NA- viruses to grow in the absence of the NA segment. The significance of these findings about naturally occurring seven-segment influenza A viruses is discussed.


Assuntos
Vírus da Influenza A/genética , Neuraminidase/genética , Replicação Viral/fisiologia , Sequência de Aminoácidos , Animais , Antivirais/farmacologia , Linhagem Celular , Microscopia Crioeletrônica , Cães , Farmacorresistência Viral/genética , Inibidores Enzimáticos/farmacologia , Regulação Enzimológica da Expressão Gênica , Regulação Viral da Expressão Gênica/fisiologia , Humanos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/enzimologia , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/enzimologia , Vírus da Influenza A/fisiologia , Modelos Moleculares , Neuraminidase/antagonistas & inibidores , Neuraminidase/química , Oseltamivir/farmacologia , Conformação Proteica , Alinhamento de Sequência , Vírion/ultraestrutura
4.
Encephale ; 33(3 Pt 1): 256-63, 2007.
Artigo em Francês | MEDLINE | ID: mdl-17675921

RESUMO

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.


Assuntos
Afeto , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
5.
Opt Express ; 15(24): 15854-62, 2007 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-19550871

RESUMO

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.

6.
Cyberpsychol Behav ; 9(2): 183-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16640476

RESUMO

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.


Assuntos
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 Piloto
7.
Opt Eng ; 45(7)2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26617422

RESUMO

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.

8.
Assessment ; 7(4): 329-45, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11172584

RESUMO

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.


Assuntos
Inventário de Personalidade , Personalidade , Psicologia do Adolescente , Adolescente , Adulto , Bélgica , Criança , Análise Fatorial , Feminino , Humanos , Masculino , Teoria Psicológica , Psicometria , Reprodutibilidade dos Testes
10.
Eur Psychiatry ; 15(1): 82-84, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11861151
11.
Appl Opt ; 39(19): 3209-15, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18349886

RESUMO

Stereoscopic head-mounted displays (HMD's) provide an effective capability to create dynamic virtual environments. For a user of such environments, virtual objects would be displayed ideally at the appropriate distances, and natural concordant accommodation and convergence would be provided. Under such image display conditions, the user perceives these objects as if they were objects in a real environment. Current HMD technology requires convergent eye movements. However, it is currently limited by fixed visual accommodation, which is inconsistent with real-world vision. A prototype multiplanar volumetric projection display based on a stack of laminated planes was built for medical visualization as discussed in a paper presented at a 1999 Advanced Research Projects Agency workshop (Sullivan, Advanced Research Projects Agency, Arlington, Va., 1999). We show how such technology can be engineered to create a set of virtual planes appropriately configured in visual space to suppress conflicts of convergence and accommodation in HMD's. Although some scanning mechanism could be employed to create a set of desirable planes from a two-dimensional conventional display, multiplanar technology accomplishes such function with no moving parts. Based on optical principles and human vision, we present a comprehensive investigation of the engineering specification of multiplanar technology for integration in HMD's. Using selected human visual acuity and stereoacuity criteria, we show that the display requires at most 27 equally spaced planes, which is within the capability of current research and development display devices, located within a maximal 26-mm-wide stack. We further show that the necessary in-plane resolution is of the order of 5 microm.

12.
Appl Opt ; 39(22): 3814-24, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18349957

RESUMO

Head-mounted projective displays (HMPD's) are a novel type of head-mounted display. A HMPD consists of a miniature projection lens mounted upon the user's head and retroreflective sheeting material placed strategically in the environment. First, the imaging concept of a HMPD is reviewed and its potential advantages and disadvantages are discussed. The design and a bench prototype implementation are then presented. Finally, the effects of retroreflective materials on the imaging properties and the optical properties of HMPD's are comprehensively investigated.

13.
Artigo em Inglês | MEDLINE | ID: mdl-10538376

RESUMO

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.


Assuntos
Simulação por Computador , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/fisiologia , Modelos Anatômicos , Algoritmos , Fenômenos Biomecânicos , Humanos
14.
J Bacteriol ; 181(14): 4193-7, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10400575

RESUMO

Transport of water across the plasma membrane is a fundamental process occurring in all living organisms. In bacteria, osmotic movement of water across the cytoplasmic membrane is needed to maintain cellular turgor; however, the molecular mechanisms of this process are poorly defined. Involvement of aquaporin water channels in bacterial water permeability was suggested by the recent discovery of the aquaporin gene, aqpZ, in Escherichia coli. By employing cryoelectron microscopy to compare E. coli cells containing (AqpZ+) and lacking (AqpZ-) aquaporin, we show that the AqpZ water channel rapidly mediates large water fluxes in response to sudden changes in extracellular osmolarity. These findings (i) demonstrate for the first time functional expression of a prokaryotic water channel, (ii) evidence the bidirectional water channel feature of AqpZ, (iii) document a role for AqpZ in bacterial osmoregulation, and (iv) define a suitable model for studying the physiology of prokaryotic water transport.


Assuntos
Aquaporinas/fisiologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/fisiologia , Microscopia Crioeletrônica/métodos , Proteínas de Escherichia coli , Escherichia coli/fisiologia , Proteínas de Membrana , Água/metabolismo , Aquaporinas/genética , Escherichia coli/genética , Concentração Osmolar
15.
Chem Phys Lipids ; 99(2): 125-37, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10390836

RESUMO

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.


Assuntos
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 Radiação
16.
J Struct Biol ; 128(3): 287-96, 1999 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-10633068

RESUMO

The MIP (major intrinsic protein) family is a widespread family of membrane proteins exhibiting two major types of channel properties: aquaporins and solute facilitators. In the present study, freeze-fracture electron microscopy was used to investigate the oligomerization state of two MIP proteins heterologously expressed in the plasma membrane of Xenopus laevis oocytes: AQPcic, an aquaporin from the insect Cicadella viridis, and GlpF, a glycerol facilitator from Escherichia coli. Swelling assays performed on oocytes 48 and 72 h following cRNA microinjections showed that these proteins were functionally expressed. Particle density determinations indicated that expression of proteins is related to an increase in particle density on the P fracture face of oocyte plasma membranes. Statistical analysis of particle sizes was performed on protoplasmic fracture faces of the plasma membrane of oocytes expressing AQPcic and GlpF 72 h after cRNA microinjections. Compared to control oocytes, AQPcic-expressing oocytes exhibited a specific population of particles with a mean diameter of 8.7 +/- 0.1 nm. This value is consistent with the previously reported tetrameric organization of AQPcic. In addition, AQPcic particles aggregate and form orthogonal arrays similar to those observed in native membranes of C. viridis, consisting of homotetramers of AQPcic. On the protoplasmic fracture face of oocytes expressing GlpF, the particle density is increased by 4.1-fold and the mean diameter of specifically added particles is 5.8 +/- 0.1 nm. This value fits with a monomer of the 28-kDa GlpF protein plus the platinum-carbon layer. These results clearly demonstrate that GlpF is a monomer when functionally expressed in plasma membranes of Xenopus oocytes and therefore emphasize the key role of the oligomerization state of MIP proteins with respect to their function.


Assuntos
Proteínas de Escherichia coli , Técnica de Fratura por Congelamento , Imunofilinas/química , Proteínas de Insetos , Proteínas de Membrana/química , Microscopia Eletrônica/métodos , Oócitos/metabolismo , Peptidilprolil Isomerase , Animais , Aquaporinas/química , Aquaporinas/genética , Aquaporinas/farmacologia , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Permeabilidade da Membrana Celular/efeitos dos fármacos , Clonagem Molecular , Escherichia coli , Expressão Gênica , Imunofilinas/genética , Proteínas de Membrana/genética , Oócitos/ultraestrutura , Tamanho da Partícula , Estrutura Quaternária de Proteína , Xenopus
17.
Micron ; 29(4): 293-6, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9744087

RESUMO

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.


Assuntos
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 , Software
18.
J Bacteriol ; 180(19): 5044-51, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9748435

RESUMO

Intracellular accumulation of sucrose in response to lowered water activity seems to occur only in photosynthetic organisms. Here we demonstrate, for the first time, the potent ability of this common sugar, supplied exogenously, to reduce growth inhibition of Sinorhizobium meliloti cells in media of inhibitory osmolarity. Independently of the nature of the growth substrates and the osmotic agent, sucrose appears particularly efficient in promoting the recovery of cytoplasmic volume after plasmolysis. Surprisingly, sucrose is not accumulated by the bacteria at an osmotically efficient level. Instead, it strongly stimulates the accumulation of the main endogenous osmolytes glutamate and N-acetylglutaminylglutamine amide (NAGGN). Examining cell volume changes during the hyperosmotic treatment, we found a close correlation between the enhancement of the osmotically active solute pool and the increase in cell volume. Sucrose shares several features with ectoine, another nonaccumulated osmoprotectant for S. meliloti. Overall, osmoregulation in S. meliloti appears to be strongly divergent from that in most bacteria.


Assuntos
Rhizobiaceae/crescimento & desenvolvimento , Sacarose/farmacologia , Betaína/farmacologia , Citoplasma , Dipeptídeos/metabolismo , Ácido Glutâmico/metabolismo , Manitol/farmacologia , Concentração Osmolar , Rhizobiaceae/citologia , Rhizobiaceae/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Sacarose/metabolismo
19.
Stud Health Technol Inform ; 50: 246-51, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10180548

RESUMO

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.


Assuntos
Apresentação de Dados , Aumento da Imagem/instrumentação , Equipamentos Cirúrgicos , Desenho de Equipamento , Movimentos da Cabeça , Humanos , Óptica e Fotônica
20.
Stud Health Technol Inform ; 50: 366-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10180573

RESUMO

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.


Assuntos
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 Articular
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