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1.
Opt Express ; 29(14): 21300-21312, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34265920

RESUMO

The superposition of two partially correlated waves is shown to produce fields with drastically altered coherence properties. It is demonstrated, both theoretically and experimentally, that two strongly correlated sources may generate a field with practically zero correlation between certain pairs of points. This anomalous change in coherence is a general phenomenon that takes place in all cases of wave superposition, including Mie scattering, as is shown. Our results are particularly relevant to applications in which it is assumed that highly coherent radiation maintains its spatial coherence on propagation, such as optical systems design and the imaging of extended sources.

2.
J Exp Med ; 152(1): 31-40, 1980 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7400755

RESUMO

A human monocyte-like cell line, U937, when grown in continuous culture, does not secrete lysosomal enzymes or migrate towards chemotactic factors. When the cells are stimulated by lymphokines, however, they develop the ability both to migrate directionally and to secrete enzymes in response to several types of chemoattractants. The development, by stimulated cells, of chemotactic and secretory responses to one class of chemoattractants, the N- formylated peptides, is accompanied by the appearance on the cells of specific binding sites for these substances. Using tritiated N-formyl- methionyl-leueyl-phenylalanine (fMet-Leu-[(3)H]Phe) as a ligand, it was determined that unstimulated U937 cells possess no detectable binding sites. However, after stimulation with lymphocyte culture supernates for 24, 48, and 72 h, they developed 4,505 (+/-) 1,138, 22,150(+/-) 4,030, and 37,200 (+/-) 8,000 sites/cell, respectively. The dissociation constants for the interaction of fMet-Leu-[SH]Phe with the binding sites were approximately the same regardless of stimulation time and ranged between 15 and 30 nM. The binding of fMet-Leu-[(3)H]Phe by stimulated U937 cells was rapid and readily reversed by the addition of a large excess of unlabeled peptide. The affinity of a series of N-formylated peptides for binding to U937 cells exactly reflected the potency of the peptides in inducing lysosomal enzyme secretion and chemotaxis. The availability of a continuous human monocytic cell line that can be induced to express receptors for N-formylated peptides will provide a useful tool not only for the characterization of such receptors but also for the delineation of regulatory mechanisms involved in cellular differentiation and the chemotactic response.


Assuntos
Fatores Quimiotáticos/metabolismo , Linfocinas/farmacologia , Metionina/análogos & derivados , Monócitos/fisiologia , N-Formilmetionina/análogos & derivados , Oligopeptídeos/metabolismo , Receptores de Droga/metabolismo , Sítios de Ligação , Ligação Competitiva , Linhagem Celular , Quimiotaxia de Leucócito , Glucuronidase/metabolismo , Humanos , Cinética , Lisossomos/enzimologia , Monócitos/citologia , Monócitos/metabolismo , Muramidase/metabolismo , N-Formilmetionina/metabolismo , N-Formilmetionina Leucil-Fenilalanina , Fatores de Tempo , Trítio
3.
Science ; 262(5131): 250-3, 1993 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-8211145

RESUMO

Interferons, which induce several intracellular antiviral proteins, also induce an extracellular soluble protein that inhibits vesicular stomatitis virus (VSV) infection. This 28-kilodalton soluble protein was purified to homogeneity and identified by protein sequencing as the ligand-binding domain of the human 160-kilodalton low density lipoprotein receptor (LDLR). The existence of an antiviral soluble LDLR was confirmed by immunoaffinity chromatography with monoclonal antibody to LDLR. This soluble receptor mediates most of the interferon-triggered antiviral activity against VSV, apparently by interfering with virus assembly or budding, and not by inhibiting virus attachment to cells.


Assuntos
Antivirais/biossíntese , Interferon gama/farmacologia , Receptores de LDL/biossíntese , Sequência de Aminoácidos , Antivirais/química , Antivirais/isolamento & purificação , Linhagem Celular , Células Cultivadas , Cromatografia de Afinidade , Meios de Cultura Livres de Soro , Efeito Citopatogênico Viral , Células HeLa , Humanos , Interferon beta/farmacologia , Dados de Sequência Molecular , Peso Molecular , Receptores de LDL/química , Receptores de LDL/isolamento & purificação , Solubilidade , Vírus da Estomatite Vesicular Indiana/crescimento & desenvolvimento
4.
Biochim Biophys Acta ; 887(1): 80-5, 1986 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-3085732

RESUMO

The effect of pretreatment with interferon (IFN) ('priming') on the production of individual IFN subtypes was studied in subpopulations of human peripheral blood mononuclear cells and in the myeloid cell line KG-1. It was found that priming had a selective enhancing effect on the production of certain IFN-alpha subtypes (IFN-alpha 20K and IFN-alpha 21K) and not on others. KG-1 cells produce both IFN-alpha and -beta; however, only the production of IFN-alpha was enhanced by priming with either IFN-alpha, beta or gamma.


Assuntos
Interferon Tipo I/sangue , Leucócitos/metabolismo , Animais , Bovinos , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Fibroblastos/metabolismo , Humanos , Interferon Tipo I/biossíntese , Interferon Tipo I/isolamento & purificação , Interferon Tipo I/farmacologia , Interferon gama/farmacologia , Rim , Cinética , Leucemia Mieloide , Linfócitos/metabolismo , Peso Molecular , Monócitos/metabolismo
5.
Immunol Lett ; 17(4): 323-8, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2453457

RESUMO

Natural-killer cell mediated cytotoxicity (NK-CMC) is modulated by interferons both at the effector cell and at the target cell levels. Pretreatment of effector cells with interferon increases their cytotoxicity while pretreatment of target cells with interferons decreases their sensitivity to NK-CMC. Interferons are inducers of several genes including those of the major histocompatibility complex (MHC) and several earlier studies have established a circumstantial correlation between induction of class I MHC gene products and induction of resistance to NK-CMC. In the present study we demonstrate that interferon-alpha renders Daudi cells resistant to NK-CMC without inducing the surface expression of class I MHC antigens. Therefore we suggest that these two phenomena are independent responses to interferon treatment.


Assuntos
Antígenos HLA/imunologia , Interferons/farmacologia , Células Matadoras Naturais/imunologia , Citotoxicidade Imunológica , Humanos , Técnicas In Vitro , Interferon Tipo I/farmacologia , Interferon gama/farmacologia , Células Tumorais Cultivadas/imunologia , Células Tumorais Cultivadas/metabolismo , Microglobulina beta-2/metabolismo
6.
Immunobiology ; 172(1-2): 110-9, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3095225

RESUMO

The effect of interferon-gamma (IFN-gamma) and bacterial lipopolysaccharide (LPS) on the cytotoxic activity of cultured monocytes was studied in a 6-h51Cr release assay with Actinomycin-D-treated tumor cells as targets. In this system, the lysis of target cells is mediated by a soluble factor (CF) which is similar or identical to human tumor necrosis factor (TNF). The spontaneous cytotoxic activity of freshly isolated monocytes declined after their maturation to macrophages during in vitro culturing. The decrease in the ability of cultured monocytes to lyse the targets is explained by a decrease in their ability to produce the soluble cytolytic factor. Both LPS and IFN-gamma modulated the effect of culturing. LPS exhibited a dual effect. Within 2-3 h after its addition, LPS enhanced the cytotoxic activity of monocytes by increasing the synthesis of CF. However, upon a longer incubation, the decay of the activity was more pronounced in the presence of LPS. IFN-gamma did not augment the cytotoxic activity of monocytes above the basal level, yet it prevented the loss of activity which accompanies the process of monocyte maturation to macrophages.


Assuntos
Citotoxicidade Imunológica/efeitos dos fármacos , Endotoxinas/farmacologia , Escherichia coli , Interferon gama/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Animais , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/imunologia
7.
J Stud Alcohol ; 36(5): 675-7, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-239290

RESUMO

A husband's membership in A.A. was related to greater marital happiness, superior ability as a father and less severe drinking problems.


Assuntos
Alcoólicos Anônimos , Alcoolismo/terapia , Família , Felicidade , Humanos , Masculino , Casamento , Pais , Fatores de Tempo
8.
Child Abuse Negl ; 22(9): 915-29, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9777261

RESUMO

OBJECTIVE: The precise nature of the differences between intrafamilial and extrafamilial child sexual abuse is not clear. The purpose of the present study is to provide clarification of these differences. METHOD: Archival data containing 1,037 cases of child sexual abuse were obtained from police files in two western Canadian cities with populations of about 180,000. Two trained research assistants coded and transcribed the data. RESULTS: Results showed: (1) earlier onset, longer duration, higher level of intrusion, and greater physical and emotional injury for intrafamilial victims; (2) less use of physical/verbal force, or enticements, and greater use of instructions "not to tell" by intrafamilial offenders; (3) more convictions and longer jail sentences for intrafamilial offenders; and (4) no intra-extrafamilial differences in victim sex preference. CONCLUSIONS: Boys are younger than girls at the time of first abuse in samples of criminal justice and hospital referrals, although only for older aged victims, for example, 8 to 17 years. Although statistically significant, there is little difference in level of intrusion perpetrated by intrafamilial and extrafamilial offenders, both are highly intrusive. Both intrafamilial and extrafamilial offenders use physical/verbal force, with older victims: extrafamilial offenders more often choose older victims, and therefore more often use force. Intrafamilial victims suffer greater physical and emotional injury, resulting from greater intrusion not duration of abuse. It's not clear that victim sex preferences of intra- and extrafamilial offenders exist.


Assuntos
Abuso Sexual na Infância , Família , Adolescente , Fatores Etários , Canadá , Criança , Maus-Tratos Infantis , Pré-Escolar , Feminino , Humanos , Masculino , Fatores Sexuais
9.
Am J Clin Hypn ; 32(3): 201-7, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2296922

RESUMO

The present study was designed to investigate the construct validity of dissociation. We administered the PAS and the DES to 507 male (48%) and female (52%) undergraduate students. Factor analysis on each scale separately showed that neither the PAS nor the DES adequately measures the three dimensions hypothesized to underlie dissociative experience. For both scales, a single factor emerged as replicable and reliable. Use of the scales, in their present form, therefore, should be limited to a single dimension representing disturbances in affect-control in the case of the PAS and disturbances in cognition-control if the DES is used at least with normal populations. Analysis of the combined items showed that the scales are measuring conceptually different but statistically correlated dimensions of dissociation. Further development of both scales is desirable, and further research should investigate the effect of different response formats on the internal structure of the scales.


Assuntos
Transtornos Dissociativos/diagnóstico , Inventário de Personalidade , Adolescente , Adulto , Afeto , Cognição , Análise Fatorial , Feminino , Humanos , Masculino
10.
Rehabil Nurs ; 18(1): 12-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8430257

RESUMO

This article describes a study designed to examine the coping behaviors, personality, and mood characteristics of 150 nonhospitalized adults with inflammatory bowel disease (IBD). Self-report questionnaires and interviews were used to collect the data. Coping responses were measured with the Jalowiec Coping Scale. The Eysenck Personality Questionnaire (EPQ) and Beck Depression Inventory (BDI) were used to ascertain other characteristics. Data were analyzed using analysis of variance (ANOVA), Pearson's correlation coefficient (r), and descriptive statistics. IBD patients scored significantly higher on using problem-oriented coping patterns than on using affective-oriented methods. The results suggest that coping patterns in IBD patients are remarkably effective in contributing to lifestyle satisfaction. It can be inferred that adaptive efforts of IBD patients can be enhanced if health professionals consider coping patterns in the assessment process and if they actively support a sense of control in these patients.


Assuntos
Adaptação Psicológica , Doenças Inflamatórias Intestinais/psicologia , Atividades Cotidianas , Adolescente , Adulto , Idoso , Feminino , Humanos , Doenças Inflamatórias Intestinais/enfermagem , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Personalidade , Inquéritos e Questionários
11.
Percept Mot Skills ; 56(2): 635-40, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6866672

RESUMO

A review of the literature suggests that parental supervision over their children is a significant variable in controlling the amount of delinquent behaviour; high supervision is associated with low delinquency. The relationship remains when variables such as mother's affection, parental conflict, parental aggression, mother's self-confidence, father's deviance, father's absence, father's occupation are controlled. And it appears to be effective under extremely adverse conditions such as poverty and authoritarian and repressive methods of child rearing. Training packages providing basic information about processes of child development and emphasizing positive techniques of child management, with parental supervision as an essential ingredient, need to be further developed and evaluated as a means of reducing delinquency.


Assuntos
Delinquência Juvenil/psicologia , Relações Pais-Filho , Adolescente , Educação Infantil , Humanos , Delinquência Juvenil/prevenção & controle , Meio Social
12.
Percept Mot Skills ; 58(2): 527-34, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6377225

RESUMO

A review of the literature shows that large family size is related to greater delinquency. The relationship remains when a number of variables, i.e., income, socioeconomic status, parental criminality, and family composition, have been controlled. The higher birth rate for lower classes does not appear to be an adequate explanation for this relationship, nor does less close parent-child affectional ties or less parental supervision although all of these may have some influence. The presence of an "infectious example" may partly account for the relationship, as does overcrowding. Large family size is typically associated with the constellation of undesirable family conditions involving poor role models (e.g., poor parental behaviour, parental criminality, sibling delinquency), poor child-rearing practices (e.g., inadequate parental supervision and discipline), and competition for physical (e.g., overcrowding, low income) and psychological (e.g., lack of attention, affection, family interaction) resources. An immediate solution is to reduce the size of families by helping prospective parents plan their families, and for those who wish it, making medical abortions more readily available. The long-range solution is through research to identify variables which significantly influence the relationship between family size and delinquency. Such studies must control for birth order, sibling spacing, siblings' sex, and sex of the delinquents in these families.


Assuntos
Características da Família , Delinquência Juvenil/psicologia , Adolescente , Educação Infantil , Aglomeração , Feminino , Humanos , Masculino , Relações Pais-Filho , Fatores Sexuais , Relações entre Irmãos , Classe Social
13.
Percept Mot Skills ; 40(2): 587-91, 1975 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1178330

RESUMO

700 Ss rated the concept abortion on a series of bipolar adjectives. Factor analysis of the ratings suggested (a) that Ss judged the concept along four orthogonal dimensions, immoral-repelling, cruel-destructive, emotional-serious, and rational-impulsive and (b) that males and females had similar factor structures. Polarity analysis showed that abortion was seen as immoral, repelling, bad, cruel, destructive, ugly, sinful, emotional, serious, rational and impulsive. Although this is highly unfavorable compared to the results of previous research, it appears to represent a liberal trend.


Assuntos
Aborto Induzido , Atitude , Adolescente , Adulto , Análise Fatorial , Feminino , Humanos , Masculino , Fatores Sexuais
14.
Percept Mot Skills ; 54(3): 751-62, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7099883

RESUMO

EEG correlates of intellectual functioning were investigated in 35 academically talented and 20 academically handicapped adolescents. EEG data from Ertl's Brainwave Analyzer were factor-analyzed and factor scores entered into regression equations predicting four primary mental abilities, verbal, numerical, reasoning, spatial, and two sequential tests of educational progress, reading and mathematics. Analysis indicated that (1) frequency ratio, with relatively greater left-hemisphere activity was the most important EEG variable related to mental functioning in the talented group; (2) while EEG period and alpha ratio were the two most important EEG variables related to intellectual functioning in the mentally handicapped group; (3) hemispheric symmetry was of some importance for both groups, with greater symmetry being associated with superior performance. Contrary to Ertl's neural efficiency theory, (1) neural information transfer rate was significantly positively (not negatively as predicted) related to intellectual performance (for the handicapped group only), and (2) alpha was significantly related to intellectual functioning (for the handicapped group only). Further research is needed to extend and confirm the above findings dealing with persons scoring in the normal IQ range and during mentally active as well as resting conditions.


Assuntos
Criança Superdotada/psicologia , Eletroencefalografia , Inteligência , Deficiências da Aprendizagem/psicologia , Adolescente , Ritmo alfa , Córtex Cerebral/fisiologia , Criança , Dominância Cerebral/fisiologia , Potenciais Evocados , Feminino , Humanos , Masculino
19.
Oecologia ; 149(4): 668-75, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16804703

RESUMO

The well-known deceleration of nitrogen (N) cycling in the soil resulting from addition of large amounts of foliar condensed tannins may require increased fine-root growth in order to meet plant demands for N. We examined correlations between fine-root production, plant genetics, and leaf secondary compounds in Populus angustifolia, P. fremontii, and their hybrids. We measured fine-root (<2 mm) production and leaf chemistry along an experimental genetic gradient where leaf litter tannin concentrations are genetically based and exert strong control on net N mineralization in the soil. Fine-root production was highly correlated with leaf tannins and individual tree genetic composition based upon genetic marker estimates, suggesting potential genetic control of compensatory root growth in response to accumulation of foliar secondary compounds in soils. We suggest, based on previous studies in our system and the current study, that genes for tannin production could link foliar chemistry and root growth, which may provide a powerful setting for external feedbacks between above- and belowground processes.


Assuntos
Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Populus/metabolismo , Proantocianidinas/metabolismo , Hibridização Genética , Polimorfismo de Fragmento de Restrição , Populus/genética , Populus/crescimento & desenvolvimento
20.
Opt Lett ; 25(20): 1529-31, 2000 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18066268

RESUMO

A generalized Radon transform is presented that relates, for the case of an evanescent wave that is incident upon a weakly scattering medium, the homogeneous components of the scattered field to the three-dimensional Fourier transform of the dielectric susceptibility. This relationship is used within the context of total internal reflection microscopy to reconstruct the depth structure of the dielectric susceptibility from simulated scattered field data.

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