966 resultados para Judgment (Human characteristics).
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The human protein Ki-1/57 was first identified through the cross reactivity of the anti-CD30 monoclonal antibody Ki-1; in Hodgkin lymphoma cells. The expression of Ki-1/57 in diverse cancer cells and its phosphorylation in peripheral blood leukocytes after mitogenic activation suggested its possible role in cell signaling. Ki-1/57 interacts with several other regulatory proteins involved in cellular signaling, transcriptional regulation and RNA metabolism, suggesting it may have pleiotropic functions. In a previous spectroscopic analysis, we observed a low content of secondary structure for Ki-1/57 constructs. Here, Circular dichroism experiments, in vitro RNA binding analysis, and limited proteolysis assays of recombinant Ki-1/57(122-413) and proteolysis assays of endogenous full length protein from human HEK293 cells suggested that Ki-1/57 has characteristics of an intrinsically unstructured protein. Small-angle X-ray scattering (SAXS) experiments were performed with the C-terminal fragment Ki-1/57(122-413). These results indicated an elongated shape and a partially unstructured conformation of the molecule in solution, confirming the characteristics of an intrinsically unstructured protein. Experimental curves together with ab initio modeling approaches revealed an extended and flexible molecule in solution. An elongated shape was also observed by analytical gel filtration. Furthermore, sedimentation velocity analysis suggested that Ki-1/57 is a highly asymmetric protein. These findings may explain the functional plasticity of Ki-1/57, as suggested by the wide array of proteins with which it is capable of interacting in yeast two-hybrid interaction assays.
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During sleep, humans experience the offline images and sensations that we call dreams, which are typically emotional and lacking in rational judgment of their bizarreness. However, during lucid dreaming (LD), subjects know that they are dreaming, and may control oneiric content. Dreaming and LD features have been studied in North Americans, Europeans and Asians, but not among Brazilians, the largest population in Latin America. Here we investigated dreams and LD characteristics in a Brazilian sample (n=3,427; median age=25 years) through an online survey. The subjects reported recalling dreams at least once a week (76%), and that dreams typically depicted actions (93%), known people (92%), sounds/voices (78%), and colored images (76%). The oneiric content was associated with plans for the upcoming days (37%), memories of the previous day (13%), or unrelated to the dreamer (30%). Nightmares usually depicted anxiety/fear (65%), being stalked (48%), or other unpleasant sensations(47%). These data corroborate Freudian notion of day residue in dreams, and suggest that dreams and nightmares are simulations of life situations that are related to our psychobiological integrity. Regarding LD, we observed that 77% of the subjects experienced LD at least once in life (44% up to 10 episodes ever), and for 48% LD subjectively lasted less than 1 min. LD frequency correlated weakly with dream recall frequency (r =0.20,p< 0.01), and LD control was rare (29%). LD occurrence was facilitated when subjects did not need to wake up early (38%), a situation that increases rapid eye movement sleep (REMS) duration, or when subjects were under stress (30%), which increases REMS transitions into waking. These results indicate that LD is relatively ubiquitous but rare, unstable, difficult to control, and facilitated by increases in REMS duration and transitions to wake state. Together with LD incidence in USA, Europe and Asia, our data from Latin America strengthen the notion that LD is a general phenomenon of the human species.
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The objective of the present study was to standardize the analysis of zinc binding on human red blood cell (RBC) membranes in 20 normal adults. The displacement studies revealed that at the maximal stable zinc concentration tested (600 muM), 57% (mean) of the bound Zn-65 was displaced and to displace half maximal Zn-65, the stable zinc concentration was 300 muM. Scatchard plots revealed two classes of binding sites for zinc on RBC membranes: one with higher affinity, Kd = 1.20 x 10(-5) M (site I), and the other with lower affinity, Kd = 2.77 x 10(-4) M (site II). Binding sites occupancy was 97% means and 58.5% means for sites I and 11, respectively. The displacement was affected by temperature, membrane protein concentration, freezing, thawing, and dialysis. Other metal cations, including Co++, Fe++, and Mn++, had very little effect on Zn-65 displacement, in contrast copper displaced Zn-65 from its binding sites on RBC membranes. Zinc binding to RBC membranes was rapid and readily reversible in a dynamic equilibrium with its binding sites. It is anticipated that this method will be applicable to studies of a wide variety of diseases specifically related to zinc metabolism in humans as well as in animals. (C) 1994 Wiley-Liss, Inc.
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This study examined the expression of epidermal growth factor (EGF) cell-surface receptors, the response to exogenous ligand and the autocrine production of transforming growth factor a (TGF-a) in normal and carcinoma-derived human oral keratinocytes. One of eight malignant cell lines overexpressed EGF receptors, while the remainder expressed receptor numbers similar to normal cells. Exogenous EGF stimulated incorporation of tritiated thymidine in a dose-dependent manner. In keratinocytes expressing normal numbers of EGF receptors, the cellular response to exogenous EGF correlated positively with total EGF receptor number. SCC-derived keratinocytes produced more TGF-a than normal cells. There was no statistical correlation between the autocrine production of TGF-a, EGF cell-surface receptor expression and cellular response to exogenous EGF. While the growth-stimulatory effects of exogenous TGF-cl were inhibited by the addition of a neutralising antibody, the presence of this antibody in conditioned medium failed to produce a similar decrease in growth. The results indicate that overexpression of EGF receptors is not an invariable characteristic of human oral squamous carcinoma-derived cell lines. Further, the contribution of TGF-a to the growth of normal and carcinoma-derived human oral keratinocytes in vitro may be less significant than previously documented.
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The present dissertation focuses on the two basic dimensions of social judgment, i.e., warmth and competence. Previous research has shown that warmth and competence emerge as fundamental dimensions both at the interpersonal level and at the group level. Moreover, warmth judgments appear to be primary, reflecting the importance of first assessing others’ intentions before determining the other’s ability to carry out those intentions. Finally, it has been shown that warmth and competence judgments are predicted by perceived economic competition and status, respectively (for a review, see Cuddy, Fiske, & Glick, 2008). Building on this evidence, the present work intends to further explore the role of warmth and competence in social judgment, adopting a finer-grained level of analysis. Specifically, we consider warmth to be a dimension of evaluation that encompasses two distinct characteristics (i.e., sociability and morality) rather than as an undifferentiated dimension (see Leach, Ellemers, & Barreto, 2007). In a similar vein, both economic competition and symbolic competition are taken into account (see Stephan, Ybarra, & Morrison, 2009). In order to highlight the relevance of our empirical research, the first chapter reviews the literature in social psychology that has studied the warmth and competence dimensions. In the second chapter, across two studies, we examine the role of realistic and symbolic threats (akin economic and symbolic competition, respectively) in predicting the perception of sociability and morality of social groups. In study 1, we measure perceived realistic threat, symbolic threat, sociability, and morality with respect to 8 social groups. In study 2, we manipulate the level and type of threat of a fictitious group and measure perceived sociability and morality. The findings show that realistic threat and symbolic threat are differentially related to the sociability and morality components of warmth. Specifically, whereas realistic threat seems to be a stronger predictor of sociability than symbolic threat, symbolic threat emerges as better predictor of morality than realistic threat. Thus, extending prior research, we show that the types of threat are linked to different warmth stereotypes. In the third and the fourth chapter, we examine whether the sociability and morality components of warmth play distinct roles at different stages of group impression formation. More specifically, the third chapter focuses on the information-gathering process. Two studies experimentally investigate which traits are mostly selected when forming impressions about either ingroup or outgroup members. The results clearly show that perceivers are more interested in obtaining information about morality than about sociability when asked to form a global impression about others. The fourth chapter considers more properly the formulation of an evaluative impression. Thus, in the first study participants rate real groups on sociability, morality, and competence. In the second study, participants read an immigration scenario depicting an unfamiliar social group in terms of high (vs. low) morality, sociability, and competence. In both studies, participants are also asked to report their global impression of the group. The results show that global evaluations are better predicted by morality than by sociability and competence trait ascriptions. Taken together the third and the fourth chapters show that the dominance of warmth suggested by previous studies on impression formation might be better explained in terms of a greater effect of one of the two subcomponents (i.e., morality) over the other (i.e., sociability). In the general discussion, we discuss the relevance of our findings for intergroup relation and group perception, as well as for impression formation.
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The present thesis illustrates the research carried out during the PhD studies in Bioengineering. The research was aimed to characterise the human bone tissue, with particular regard to the differences between cortical and trabecular bone. The bone tissue characteristics that affect its mechanical properties were verified or identified, using an experimental approach, to corroborate or refute hypotheses based on the state of the art in bone tissue biomechanics. The studies presented in the present PhD thesis were designed to investigate aspects of bone tissue biomechanics, which were in need of a more in-depth examination since the data found in the literature was contradictory or scarce. In particular, the work was focalised on the characterisation of the basic structure of the bone tissue (groups of lamellae), its composition, its spatial organisation (trabecular bone microarchitecture) and their influence on the mechanical properties. In conclusion, the present thesis integrates eight different studies on the characterisation of bone tissue. A more in-depth examination of some of the aspects of bone tissue biomechanics where the data found in the literature was contradictory or scarce was performed. Bone tissue was investigated at several scales, from its composition up to its spatial organization, to determine which parameters influence the mechanical behaviour of the tissue. It was found that although the composition and real density of bone tissue are similar, the differences in structure at different levels cause differences between the two types of bone tissue (cortical and trabecular) in mechanical properties. However, the apparent density can still be considered a good predictor of the mechanical properties of both cortical and trabecular bone. Finally, it was found that the bone tissue characteristics might change when a pathology is present, as demonstrated for OA.
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The work environment characteristics of job stress, job variety, job autonomy, and supervision are theorized to affect the job satisfaction and organizational commitment of social and human service workers. Most research to date has focused upon the impact of these variables on job satisfaction, with little attention being paid to organizational commitment. To determine the effects these characteristics have on both job satisfaction and organizational commitment, data from a survey of social and human service employees across Northwest Ohio were examined. In Ordinary Least Squares regression, all four job characteristics had a significant impact on job satisfaction, while only job variety and supervision had statistically significant effects on organizational commitment.
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Regulation of colonic epithelial cell proliferation and differentiation remains poorly understood due to the inability to design a model system which recapitulates these processes. Currently, properties of "differentiation" are studied in colon adenocarcinoma cell lines which can be induced to express some, but not all of the phenotypes of normal cells. In this thesis, the DiFi human colon adenocarcinoma cell line is utilized as an in vitro model system in which to study mucin production. In response to treatment with tumor necrosis factor-alpha, DiFi cells acquire some properties of mucin-producing goblet cells including altered morphology, increased reactivity to wheat germ agglutinin, and increased mucin production as determined by RNA expression as well as reactivity with the MUC-1 antibodies, HMFG-1 and SM-3. Thus, TNF-treated DiFi cells represent one of the few in vitro systems in which mucin expression can be induced.^ DiFi cells express an activated pp60$\sp{{\rm c}-src},$ as do most colon adenocarcinomas and derived cell lines, as well as an amplified epidermal growth factor (EGF) receptor. To assess potential changes in these enzymes during induction of differentiation characteristics, potential changes in the levels and activities of these enzymes were examined. For pp60$\sp{{\rm c}-src},$ no changes were observed in protein levels, specific activity of the kinase, cellular localization, or phosphorylation pattern as determined by Staphylococcus aureus V8 protease partial proteolytic mapping after induction of goblet cell-like phenotypic changes. These results suggest that pp60$\sp{{\rm c}-src}$ is regulated differentially in goblet cells than in absorptive cells, as down-modulation of pp60$\sp{{\rm c}-src}$ kinase occurs in the latter. Therefore, effects on pp60$\sp{{\rm c}-src}$ may be critical in colon regulation, and may be important in generating the various colonic epithelial cell types.^ In contrast to pp60$\sp{{\rm c}-src},$ EGF receptor tyrosine kinase activity decreased ($<$5-fold) after TNF treatment and at the time in which morphologic changes were observed. Similar decreases in tyrosine phosphorylation of EGF receptor were observed as assessed by immunoblotting with an anti-phosphotyrosine antibody. In addition, ($\sp{125}$I) -EGF cell surface binding was reduced approximately 3-fold following TNF treatment with a concomitant reduction in receptor affinity ($<$2-fold). These results suggest that modulation of EGF receptor may be important in goblet cell differentiation. In contrast, other published studies have demonstrated that increases in EGF receptor mRNA and in ($\sp{125}$I) -EGF binding accompany differentiation toward the absorptive cell phenotype. Therefore, differential regulation of both EGF receptor and pp60$\sp{{\rm c}-src}$ occur along the goblet cell and absorptive cell differentiation pathways. Thus, my results suggest that TNF-treated DiFi cells represent a unique system in which to study distinct patterns of regulation of pp60$\sp{{\rm c}-src}$ and EGF receptor in colonic cells, and to determine if increased MUC-1 expression is an early event in goblet cell differentiation. ^
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An understanding of spatial patterns of plant species diversity and the factors that drive those patterns is critical for the development of appropriate biodiversity management in forest ecosystems. We studied the spatial organization of plants species in human- modified and managed oak forests (primarily, Quercus faginea) in the Central Pre- Pyrenees, Spain. To test whether plant community assemblages varied non-randomly across the spatial scales, we used multiplicative diversity partitioning based on a nested hierarchical design of three increasingly coarser spatial scales (transect, stand, region). To quantify the importance of the structural, spatial, and topographical characteristics of stands in patterning plant species assemblages and identify the determinants of plant diversity patterns, we used canonical ordination. We observed a high contribution of ˟-diversity to total -diversity and found ˟-diversity to be higher and ˞-diversity to be lower than expected by random distributions of individuals at different spatial scales. Results, however, partly depended on the weighting of rare and abundant species. Variables expressing the historical management intensities of the stand such as mean stand age, the abundance of the dominant tree species (Q. faginea), age structure of the stand, and stand size were the main factors that explained the compositional variation in plant communities. The results indicate that (1) the structural, spatial, and topographical characteristics of the forest stands have the greatest effect on diversity patterns, (2) forests in landscapes that have different land use histories are environmentally heterogeneous and, therefore, can experience high levels of compositional differentiation, even at local scales (e.g., within the same stand). Maintaining habitat heterogeneity at multiple spatial scales should be considered in the development of management plans for enhancing plant diversity and related functions in human-altered forests
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Human endogenous retroviruses (HERVs) are very likely footprints of ancient germ-cell infections. HERV sequences encompass about 1% of the human genome. HERVs have retained the potential of other retroelements to retrotranspose and thus to change genomic structure and function. The genomes of almost all HERV families are highly defective. Recent progress has allowed the identification of the biologically most active family, HTDV/HERV-K, which codes for viral proteins and particles and is highly expressed in germ-cell tumors. The demonstrable and potential roles of HTDV/HERV-K as well as of other human elements in disease and in maintaining genome plasticity are illustrated.
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National Highway Traffic Safety Administration, Washington, D.C.
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Binding: blue cover, intricate illustrations in red and gilt on front cover and spine, marbled edges, floral endpapers
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Mode of access: Internet.