145 resultados para dimension groups


Relevância:

20.00% 20.00%

Publicador:

Resumo:

1. Free-living animals make complex decisions associated with optimizing energy and nutrient intake. In environments where ambient temperatures fall below the thermoneutral zone, homeotherms must choose whether or not to forage, how long and what to forage for, and whether or not to perform activities that conserve energy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The substituted tris(bipyridine)ruthenium(II) complexes {[Ru(bpy)(2)(4,4'-bbob)](2+) and [Ru(bpy)(2)(5,5'-bbob)](2+) [where bpy = 2,2'-bipyridine and bbob = bis(benzoxazol-2-yl)-2,2'-bipyridine] have been prepared and compared to the previously studied complex [Ru(bpy)(2)(4,4'-bbtb)](2+) [where bbtb = bis(benzothiazol-2-yl)-2,2'-bipyridine]. From the UV/VIS titration studies, Delta-[Ru(bpy)(2)(4,4'bbob)](2+) displays a stronger association than the Lambda-isomer with calf-thymus DNA (ct-DNA). For [Ru(bpy)(2)(5,5'-bbob)](2+), there appears to be minimal interaction with ct-DNA. The results of fluorescence titration studies suggest that [Ru(bpy)(2)(4,4'-bbob)](2+) gives an increase in emission intensity with increasing ct-DNA concentrations, with an enantiopreference for the A isomer, confirmed by membrane dialysis studies. The fluorescent intercalation displacement studies revealed that [Ru(bpy)(2)(4,4'-bbob)](2+) and [Ru.(bpy)(2)(5,5'bbob)](2+) display a preference for more open DNA structures such as bulge and hairpin sequences. While Delta-[Ru(bpy)(2)(4,4'-bbtb)](2+) has shown the most significant affinity for all the oligonucleotides sequences screened in previous studies, it is the A isomer of the comparable benzoxazole ruthenium(II) complex (Delta-[Ru(bpy)(2)(4,4'-bbob)](2+)) that preferentially binds to DNA.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this study was to determine the extent to which adults with Down syndrome (DS) are able to utilise advance information to prepare reach to grasp movements. The study comprised ten adults with DS; ten children matched to an individual in the group with DS on the basis of their intellectual ability, and twelve adult controls. The participants used their right hand to reach out and grasp illuminated perspex blocks. Four target blocks were positioned on a table surface, two to each side of the midsagittal plane. In the complete precue condition, participants were provided with information specifying the location of the target. In the partial precue condition, participants were given advance information indicating the location of the object relative to the midsagittal plane (left or right). In the null condition, advance information concerning the position of the target object was entirely ambiguous. It was found that both reaction times and movement times were greater for the participants with DS than for the adults without DS. The reaction times exhibited by individuals with DS in the complete precue condition were lower than those observed in the null condition, indicating that they had utilised advance information to prepare their movements. In the group with DS, when advance information specified only the location of the target object relative to the midline, reaction times were equivalent to those obtained when ambiguous information was given. In contrast, the adults without DS exhibited reaction times that were lower in both the complete and partial precue conditions when compared to the null condition. The pattern of results exhibited by the children was similar to that of the adults without DS. The movement times exhibited by all groups were not influenced by the precue condition. In summary, our findings indicate that individuals with DS are able to use advance information if it specifies precisely the location of the target object in order to prepare a reach to grasp movement. The group with DS were unable, however, to obtain the normal advantage of advance information specifying only one dimension of the movement goal (i.e., the position of an object relative to the body midline). (C) 2001 Elsevier Science B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Ionic liquid crystals were obtained by coupling one or two mesogenic units (cholesterol or cyanobiphenyl) to an imidazolium cation. Anions are bromide, bis(trifluoromethylsulfonyl)imide, and tetrakis(2-thenoyltrifluoroacetonato)europate(III). The mesomorphism of the compounds depends on the type and number of mesogenic units and on the type of anion. In general, the most stable mesophases are observed for the bis(trifluoromethylsulfonyl)imide salts. Most of the compounds containing cholesterol moieties show enantiotropic SmA* phases over a broad temperature range, and some of them are room temperature liquid crystals. Modeling of the small-angle X-ray scattering patterns revealed the molecular arrangement in these mesophases. On the contrary, most of the compounds containing cyanobiphenyl groups exhibit monotropic lamellar or nematic mesophases, depending on the number of mesogenic units. The imidazolium salts containing the tetrakis(2-thenoyltrifluoroacetonato)europate(III) anion show an intense red photoluminescence.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this article the authors discuss the usefulness of focus groups for researching sensitive issues using evidence from a study examining the experiences of nurses providing care in the context of the Northern Ireland Troubles. They conducted three group interviews with nurses during which they asked about the issues the nurses face(d) in providing nursing care amid enduring social division. Through a discursive analysis of within-group interaction, they demonstrate how participants employ a range of interpretive resources, the effect of which is to prioritize particular knowledge concerning the nature of nursing care. The identification of such patterned activity highlights the ethnographic value of focus groups to reveal social conventions guiding the production of accounts but also suggests that accounts cannot be divorced from the circumstances of their production. Consequently, the authors argue that focus groups should be considered most useful for illuminating locally sanctioned ways of talking about sensitive issues.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

New ionic liquid crystals (including ionic metallomesogens) based oil the pyrrolidinium core are presented. N-Methylpyrrolidine was quaternized with different mesogenic groups connected to a flexible, omega-bromosubstituted alkyl spacer. The length of the flexible alkyl spacer between the cationic head group and the rigid mesogenic group was varied. The substituted pyrrolidinium cations were combined with bromide, bis(trifluoromethylsulfonyl)imide, tetrakis (2-thenoyltrifluoroacetonato)europate(III), and tetrabromouranyl anions. The influence of the type of mesogenic unit, the lengths of the flexible spacer and terminal alkyl chain, the size of the mesogenic group, and the type of anion oil the thermotropic mesomorphic behavior was investigated. Furthermore, the phase behavior was thoroughly compared with the previously reported mesomorphism of N-alkyl-N-methylpyrrolidinium salts. Low-ordered smectic A phases of the de Vries type, smectic C phases, higher-ordered smectic F/I phases, as well its crystal smectic phases (E and G, J, H, or K) were observed and investigated by polarizing optical microscopy, differential scanning calorimetry, and powder X-ray diffraction.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The process of divorce as a family change process including outcomes and consequences has received considerable research attention in the western context. However, the experience of divorce for children within specific ethnic contexts has been rather limited leading to poor planning and practice provision with diverse families. By drawing upon an empirical qualitative study of British Indian adult children, this paper will make a case for recognising diverse needs within specific historical, socio-cultural and developmental contexts. There is a need to acknowledge these contexts in policy design to establish practice that is flexible, accessible and relevant to the needs of different and diverse communities. Results indicate that areas of impact may be similar to those identified by other studies within the literature review. However, the experiences, expressions, implications and larger consequences of impact are located within specific socio-cultural contexts. In support of this, major findings of the study (outlined below) will be discussed - Context: patriarchy, stigma, immigration; Impact: economic, social, emotional, career/education, physical; Coping: psychological strategies, physical strategies, social strategies, sources of support.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Rather than treating conservative Protestantism as a homogenous phenomenon, recent literature has underlined the importance of disaggregating this group to illuminate important attitudinal and behavioral differences between conservative Protestants. However, the methods used to empirically operationalize conservative Protestantism have not always been able to capture variations within the groupings. Based on analysis of the 2004 Northern Ireland Life and Times Survey, we argue that religious self-identification is a more useful way of analyzing conservative Protestant subgroups than denomination or religious belief. We show that many of these identifications are overlapping, rather than stand-alone, religious group identifications. Moreover, the identification category of born-again has seldom been included in surveys. We find having a born-again identification to be a better predictor than the more frequently asked fundamentalist and evangelical categories of the religious and social beliefs that are seen as indicative of conservative Protestantism.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper appears in the Canadian-based, leading interprofessional education journal. Pre-qualification healthcare education can be viewed as having three inter-related components, intra-professional, interprofessional and intra-personal learning; the third of these underpinning the other two. Understanding more about personal learning needs can contribute to preparation for interprofessional interaction. A Studying and Learning Preferences Inventory (SALPI) was developed and validated for use with a range of healthcare professionals to assist in this process.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This research rests on the assumption that individual differences approaches to prejudice benefit from all integration of intergroup factors. Following Duckitt (2001), we assumed that two prominent individual differences variables, right-wing authoritarianism (RWA) and social dominance orientation (SDO), would differentially predict majority members' levels of ethnic prejudice depending on specific factors of the intergroup context: RWA as all index of motivational concerns about social cohesion, stability and security should drive prejudice against outgroups perceived as socially threatening, and SDO as an index of concerns about ingroup superiority and dominance should predict prejudice against outgroups perceived as potential competitors for power-status. Across two studies (Ns = 82, 176), using between-participants and within-participants experimental designs, the effects of RWA on prejudice were particularly powerful when the outgroup was manipulated to be socially threatening, but the effects of SDO on prejudice appeared not to increase when the outgroup was manipulated to be competitive. In Study 2, presenting the outgroup as having low status also increased the effect of RWA, but not the effect of SDO. These results support the differential prediction assumption for RWA, but not for SDO. Implications for the conceptualisation of RWA and SDO are discussed. Copyright (C) 2008 John Wiley & Sons, Ltd.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Authoritarianism, comprising conventionalism, authoritarian submission, and authoritarian aggression, is an important factor underlying prejudice and social discrimination and therefore is typically perceived as socially problematic. In contrast, our work examines adaptive features of authoritarianism. Evolutionary game theoretical considerations (e.g., biased social learning) point to authoritarian psychological processes that establish and foster group life (e.g., high levels of ingroup cooperation). First, the evolution of social learning (particularly conformist and prestige biases) leads to the establishment of local and distinct cultural groups (conventionalism). Second, local cultural rules solve coordination dilemmas by transforming these rules into normative standards against which others are evaluated (authoritarian submission). Third, the common rules within a particular culture or group are reinforced by a tendency to reward norm compliance and punish norm deviations (authoritarian aggression). Implications regarding the deduction of novel research questions as well as dealing with authoritarianism as a social problem are discussed.