1,611 research outputs found
Antartic/Scotia plate convergence off southernmost Chile
The southern tip of South America off Chile has suffered a long phase of ocean-continent convergence which has shaped the continental margin through different phases of accretion and tectonic erosion. The present accretionary wedge is a discontinuous geological record of plate convergence and records only part of the accretionary processes resumed after Chile ridge consumption (14 Ma). The structural style of the subduction complex, such as rates of sediment accretion and tectonic erosion, structural vergence, width of the accretionary wedge, taper angle and deformation in the forearc basin, varies along the margin. Large taper values are related to narrow wedges and seaward vergent structures. Low tapers occur where deformation at the toe of the accretionary complex is spread over wide areas and is related both to landward and seaward vergent thrust faults. Seismic data interpretation contributes to define more accurately frontal wedge morphology and geometry of subduction and suggests that different modes of accretion together with tectonic erosion may be active concurrently along the trench at different locations. In areas of subduction driven accretionary processes the majority of trench sediments are involved in accretionary processes and sediments are uplifted and piled up in the form of imbricate thrust sheets. In areas where the wedge is non-accretionary the continental margin shows steeper continental slopes associated with narrow accretionary wedges, more intense sediment disruption and very shallow décollement levels. Variation in structural style and in the geometry of the forearc region setting off Southernmost Chile, has been interpreted as related to the existence of different structural domains: the nature of their boundaries is still unclear mainly for the lack of high resolution bathymetric data. They have been tentatively related to tectonic lineaments belonging to the Magellan Fault system and/or to the character and morphology of the converging plates (lateral heterogeneities, sea-mounts and fracture zones), which produce a segmentation of the margin
Too Nice to be Dominant: How Brand Warmth Impacts Perceptions of Market Dominance
Consumers are unaware of brands’ market dominance. This is important given that even misperception as a market leader has been shown to lead to positive evaluations from consumers. We hypothesize that when consumers are lacking direct knowledge about a brand’s market dominance, brand image is used as a cue for inference making: specifically, a brand with a warm, kind, and generous image will be in conflict with perceptions of market dominance, which are perceived as an embodiment of power. Thus high warmth brands will be perceived as less market dominant than low warmth brands.
In study 1, we use real brands in two product categories in which participants had little knowledge about brands’ market dominance, cough syrup and fabric softener. We found that consistent with our hypothesis, the brands which had an image built around being kind, caring and generous and thus seen as high warmth were estimated to have a lower market share than a low warmth brand. Study 2 replicates the findings of Study 1 except that we presented participants with descriptions of fictitious brands that varied on warmth and were in two new product categories (pens and adhesive bandages). Using the same cough syrup brands as in Study 1, Study 3 builds on the findings of Studies 1 and 2 by demonstrating the effect of brand image warmth on perceptions of market dominance is driven by reduced perceptions of competitiveness in the market. High warmth brands were perceived as being less competitive in their product category which led to lower perceptions of market dominance. In Study 4, we investigate category knowledge as a boundary condition for this effect by using a product category, soup, for which our participant group, college students, have a high variance of knowledge. We hypothesize and find that category knowledge is a predictor of market dominance for a highly dominant, high warmth brand but not for a low warmth brand. Our final study demonstrates the potential impact of this effect on preference for brands by demonstrating consistent with prior literature demonstrating that more dominant brands are preferred in self-relevant conditions, the high warmth and thus perceived to be less dominant brands were less preferred when the choice situation was highly self-relevant
The 2013 Lunigiana (Central Italy) earthquake: Seismic source analysis from DInSar and seismological data, and geodynamic implications for the northern Apennines. A discussion
We refine the geological data of the 2013 Lunigiana EQ of Pezzo et al. (2014)
We report structural constraints for the seismic source of the 2013 Lunigiana EQ.
We underline the role of tectonic inheritance for the seismogenic faul
Bone quality in relation to skeletal maturation in palatal miniscrews insertion sites
Introduction: This study aimed to investigate the relationship between bone density and quantity at the insertion sites of palatal miniscrews and skeletal maturation—evaluated with the middle phalanx maturation method—in growing patients. Methods: Sixty patients were analyzed as having a staged third finger middle phalanx radiograph and a cone-beam computed tomography of the maxilla. On the cone-beam computed tomography, a grid was designed to parallel the midpalatal suture (MPS) and posterior to the nasopalatine foramen, both on the palatal and lower nasal cortical bones. Bone density and thickness were measured at the intersections, and medullary bone density was also calculated. Results: Of patients in MPS stages 1-3, 67.6% showed a mean palatal cortical thickness of 1 mm. The nasal cortical thickness showed a similar trend (MPS stages 1-3: 62.16% 1 mm). There was a significant difference in the density of the palatal cortical bone between MPS stages 1-3 (1272.05 ± 191.13) and stages 4 and 5 (1572.33 ± 274.89) and in nasal cortical density between MPS stages 1-3 (1428.09 ± 198.97) and stages 4 and 5 (1597.97 ± 267.75) (P <0.001). Conclusions: This study revealed a correlation between skeletal maturity and maxillary bone quality. MPS stages 1-3 have lower palatal cortical bone density and thickness but high nasal cortical bone density values. MPS stage 4 and, even more, stage 5 show increasing palatal cortical bone thickness and palatal and nasal cortical bone density values
Electron correlation in C_(4N+2) carbon rings: aromatic vs. dimerized structures
The electronic structure of C_(4N+2) carbon rings exhibits competing
many-body effects of Huckel aromaticity, second-order Jahn-Teller and Peierls
instability at large sizes. This leads to possible ground state structures with
aromatic, bond angle or bond length alternated geometry. Highly accurate
quantum Monte Carlo results indicate the existence of a crossover between C_10
and C_14 from bond angle to bond length alternation. The aromatic isomer is
always a transition state. The driving mechanism is the second-order
Jahn-Teller effect which keeps the gap open at all sizes.Comment: Submitted for publication: 4 pages, 3 figures. Corrected figure
Cultural determinants of status: Implications for workplace evaluations and behaviors
Status is a valued workplace resource that facilitates career success, yet little is known regarding whether and how cultural orientation affects status attainment. We integrate status characteristics theory with the literature on individualism and collectivism and propose a cultural patterning in the determinants of status. Four studies (N = 379) demonstrate that cultural orientation influences the tendency to view high status individuals as competent versus warm (Study 1), uncover cultural differences in both individuals’ tendency to engage in competence and warmth behaviors to attain workplace status (Study 2) and evaluators’ tendency to ascribe status to individuals who demonstrate competence versus warmth (Study 3), and verify that cultural differences in the effects of competence and warmth on status perceptions, and in turn performance evaluations, generalize to real world interdependent groups (Study 4). Our findings advance theory on the cultural contingencies of status attainment and have implications for managing diversity at work
Detection of possible factors favouring the evolution of migraine without aura into chronic migraine
In a minority of cases, the natural history of migraine without aura (MO) is characterised over time by its evolution into a form of chronic migraine (CM). In order to detect the possible factors predicting this negative evolution of MO, we searched in our Headache Centre files for all clinical records that met the following criteria: (a) first visit between 1976 and 1998; (b) diagnosis of MO or of common migraine at the first observation, with or without association with other primary headache types; (c) <15 days per month of migraine at the first observation; and (d) at least one follow-up visit at least 10 years after the first visit. The patients thus identified were then divided into two groups based on a favourable/steady evolution (Group A: n = 243, 195 women and 48 men) or an unfavourable evolution (Group B: n = 72, 62 women and 10 men) of their migraine over time. In the two groups, we compared various clinical parameters that were present at the first observation or emerged at the subsequent follow-up visits. The parameters that were statistically significantly more frequent in Group B--and can therefore be considered possible negative prognostic factors--were: (a) ≥ 10 days per month of migraine at the first observation; (b) presence of depression at the first visit in males; and (c) onset of depression or arterial hypertension after the first observation but before transformation to CM in females. Based on these findings, in MO patients the high frequency of migraine attacks, comorbidity with depression, and the tendency to develop arterial hypertension should require particular attention and careful management to prevent evolution into CM
Barley beta-glucan promotes MnSOD expression and enhances angiogenesis under oxidative microenvironment
Manganese superoxide dismutase (MnSOD), a foremost antioxidant enzyme, plays a key role in angiogenesis. Barley-derived (1.3) β-d-glucan (β-d-glucan) is a natural water-soluble polysaccharide with antioxidant properties. To explore the effects of β-d-glucan on MnSOD-related angiogenesis under oxidative stress, we tested epigenetic mechanisms underlying modulation of MnSOD level in human umbilical vein endothelial cells (HUVECs) and angiogenesis in vitro and in vivo. Long-term treatment of HUVECs with 3% w/v β-d-glucan significantly increased the level of MnSOD by 200% ± 2% compared to control and by 50% ± 4% compared to untreated H2O2-stressed cells. β-d-glucan-treated HUVECs displayed greater angiogenic ability. In vivo, 24 hrs-treatment with 3% w/v β-d-glucan rescued vasculogenesis in Tg (kdrl: EGFP) s843Tg zebrafish embryos exposed to oxidative microenvironment. HUVECs overexpressing MnSOD demonstrated an increased activity of endothelial nitric oxide synthase (eNOS), reduced load of superoxide anion (O2-) and an increased survival under oxidative stress. In addition, β-d-glucan prevented the rise of hypoxia inducible factor (HIF)1-α under oxidative stress. The level of histone H4 acetylation was significantly increased by β-d-glucan. Increasing histone acetylation by sodium butyrate, an inhibitor of class I histone deacetylases (HDACs I), did not activate MnSOD-related angiogenesis and did not impair β-d-glucan effects. In conclusion, 3% w/v β-d-glucan activates endothelial expression of MnSOD independent of histone acetylation level, thereby leading to adequate removal of O2-, cell survival and angiogenic response to oxidative stress. The identification of dietary β-d-glucan as activator of MnSOD-related angiogenesis might lead to the development of nutritional approaches for the prevention of ischemic remodelling and heart failure
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