36 resultados para mixed-orientation relationships


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A new terrestrial-marine assemblage from the lower beds of a thin outcrop section of the Kockatea Shale in the northern Perth Basin, Western Australia, contains a range of fossil groups, most of which are rare or poorly known from the Lower Triassic of the region. To date, the collection includes spinose acritarchs, organic-cemented agglutinated foraminifera, lingulids, minute bivalves and gastropods, ammonoids, spinicaudatans, insects, austriocaridid crustaceans, actinopterygians, a temnospondyl-like mandible, plant remains, and spores and pollen. Of these groups, the insects, crustaceans and macroplant remains are recorded for the first time from this unit. Palynomorphs permit correlation to nearby sections where conodonts indicate an early Olenekian (Smithian) age. The locality likely represents the margin of an Early Triassic shallow interior sea with variable estuarine-like water conditions, at the southwestern end of an elongate embayment within the East Gondwana interior rift-sag system preserved along the Western Australian margin. Monospecific spinose acritarch assemblages intertwined with amorphous organic matter may represent phytoplankton blooms that accumulated as mats, and suggest potentially eutrophic surface waters. The assemblage represents a mixure of marine and terrestrial taxa, suggesting variations in water conditions or that fresh/brackish-water and terrestrial organisms were transported from adjacent biotopes. Some of the lower dark shaly beds are dominated by spinicaudatans, likely indicating periods when the depositional water body was ephemeral, isolated, or subjected to other difficult environmental conditions. The biota of the Kockatea Shale is insufficiently known to estimate biotic diversity and relationships of individual taxa to their Permian progenitors and Triassic successors, but provides a glimpse into a coastal-zone from the interior of eastern Gondwana. Specialist collecting is needed to clarify the taxonomy of many groups, and comparisons to other Lower Triassic sites are required to provide insights into the pattern of biotic decline and recovery at the end-Permian crisis.

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Binary and ternary nanocomposites were produced by incorporating, via melt compounding, two types of octa-and dodecaphenyl substituted polyhedral oligomeric silsesquioxanes (POSS), montmorillonite (MMT), and combinations of POSS with MMT into nylon 6. The tensile, flexural, and dynamic thermo-mechanical properties of these materials were characterized and their structure-property relationships discussed. The results show that the losses in ductility and toughness experienced after inclusion of MMT into nylon 6 can be balanced out by co-mixing MMT with the dodecaphenyl- POSS to produce a ternary nanocomposite. This trend however was less pronounced in the ternary MMT/octaphenyl-POSS system. Analysis of the microstructure organization in these materials using XRD and SEM sheds some light on understanding the differences in behavior. Both types of POSS particles mixed alone in nylon 6 were found to be polydisperse (500 nm to a few microns in size) and locally aggregated, yielding materials with similar mechanical performance. The co-mixing of MMT with the octaphenyl- POSS served to break down the POSS crystal aggregates, enhancing their micro-mechanical reinforcing action. On the other hand, the POSS crystals were not affected in the MMT/dodecaphenyl-POSS system, which led to improving their toughening ability.

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Abstract
The transition from adolescence to young adulthood is a watershed period in development that carries risk for poor psychosocial adjustment. It also carries potential for positive transitions into the caregiving roles and responsibilities of adult life. Research to date has predominantly focused on adolescent predictors of problematic rather than positive transitions; yet predictors of the latter hold equal (if not greater) promise for informing health promoting interventions. The purpose of this study was threefold: (1) to use Latent Profile Analysis (LPA) to define patterns of psychosocial adjustment and maladjustment in young adulthood (21-years of age); (2) to examine the unique role of adolescent prosocial behaviour (e.g., volunteering and civic engagement) in promoting adjustment and reducing maladjustment in young adulthood; and, (3) to examine whether protective developmental relationships are maintained after adjustment for other covariates including socio-economic background factors and personality characteristics. Data were drawn from the Victorian cohort of the International Youth Development Study (IYDS; N = 2407), a representative sample of students in Victoria, Australia. Students were assessed in Grade 9 (Mean age = 15-years) and followed up at age 21-years. LPA identified three psychosocial adjustment classes at age 21 defined as: (1) Adjusted (24.8 %); (2) Normative (63.9 %); and, (3) Maladjusted (11.3 %). Adolescent volunteering, belief in a moral order, family opportunities for prosocial behaviour, and commitment to school were associated with enhanced adjustment and reduced maladjustment in young adulthood. Findings highlight the potential benefit of interventions designed to enhance adolescent prosocial behaviours and care orientation in promoting healthy transitions into young adult life.

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Purpose – The purpose of this paper is to examine the effects of market orientation on exploratory and exploitative innovation, and the moderating effects of family ownership on these relationships. Design/methodology/approach – This study utilizes multi-group path analysis and confirmatory factor analysis in LISREL on data from 228 firms in the Australian service sector. Findings – This study establishes that both customer and competitor innovation are positively related to exploitative and exploratory innovation. However, customer orientation does not lead to significantly stronger effects on exploitative innovation than on exploratory innovation, and competitor orientation does not lead to significantly stronger effects on exploratory innovation than on exploitative innovation. In addition, the study found that the relationship between customer orientation and exploratory innovation was stronger for family firms, while the relationships between competitor orientation and both exploratory and exploitative innovation were stronger for non-family firms. Research limitations/implications – The cross-sectional design is one weakness of this study. In addition, as firms in the present study came from the service sector the generalizability of the findings to other sectors of the economy need to be determined. Practical implications – These findings of this study highlight the need for managers to build a strong market orientation in order to promote innovation, and consider the effects of ownership structure on innovation strategies. Originality/value – This study is the first to measure the relative influence of customer and competitor orientation on a firm’s use of exploitative and exploratory innovation strategies.

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Mother-child mealtime interactions during preschool years is an important but overlooked factor when evaluating the influence of parent-child relationships on child eating and weight. This paper describes the validation of the Mutually Responsive Orientation (MRO) coding system adapted for assessing parent-child interactions during food preparation and consumption situations. Home-based mealtimes of 94 mothers and their children (3.03 ± 0.75 years) were filmed at two time points, 12-months apart. Filmed dimensions of mutual mother-child responsiveness, shared positive affect, maternal control relating to food and child compliance were assessed. Objective BMI and maternal reports of parenting, feeding, child eating, diet and child temperament were also collected. Correlations, repeated measures ANOVAs and regressions were performed to examine the validity of MRO variables and their stability across both time points. Validation analysis showed the MRO coding system performed as expected: dyads with higher MRO scores expressed lower control/power assertion, lower child non-compliance, and greater committed compliance. The measure demonstrated sensitivity to specific contexts: maternal responsiveness, mother and child positive affect were higher during food consumption compared to food preparation. Coded dimensions were stable across time points, with the exception of decreases in maternal responsiveness in food consumption and child non-compliance in food preparation. MRO and maternal dimensions were correlated with maternally reported parenting and feeding measures. Maternal responsiveness (inversely) and child responsiveness (positively) were concurrently associated with child fussy eating, and child refusal was prospectively and inversely associated with child fussy eating. Findings suggest the adapted MRO coding system is a useful measure for examining observed parent-child mealtime interactions potentially implicated in preschoolers' eating and weight development.

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Social organization is often studied through point estimates of individual association or interaction patterns, which does not account for temporal changes in the course of familiarization processes and the establishment of social dominance. Here, we present new insights on short-term temporal dynamics in social organization of mixed-sex groups that have the potential to affect sexual selection patterns. Using the live-bearing Atlantic molly (Poecilia mexicana), a species with pronounced male size polymorphism, we investigated social network dynamics of mixed sex experimental groups consisting of eight females and three different-sized males over a period of 5 days. Analyzing association-based social networks as well as direct measures of spatial proximity, we found that large males tended to monopolize most females, while excluding small- and medium-bodied males from access to females. This effect, however, emerged only gradually over time, and different-sized males had equal access to females on day 1 as well as day 2, though to a lesser extent. In this highly aggressive species with strong social dominance stratifications, the observed temporal dynamics in male-female association patterns may balance the presumed reproductive skew among differentially competitive male phenotypes when social structures are unstable (i.e., when individual turnover rates are moderate to high). Ultimately, our results point toward context-dependent sexual selection arising from temporal shifts in social organization.