258 resultados para 7441-105


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We put forward a new experimental economics design with monetary incentives to estimate students’ perceptions of grading discrimination. We use this design in a large field experiment which involved 1,200 British students in grade 8 classrooms across 29 schools. In this design, students are given an endowment they can invest on a task where payoff depends on performance. The task is a written verbal test which is graded non anonymously by their teacher, in a random half of the classrooms, and graded anonymously by an external examiner in the other random half of the classrooms. We find significant evidence that students’ choices reflect perceptions of biases in teachers’ grading practices. Our results show systematic gender interaction effects: male students invest less with female teachers than with male teachers while female students invest more with male teachers than with female teachers. Interestingly, female students’ perceptions are not in line with actual discrimination: Teachers tend to give better grades to students of their own gender. Results do not suggest that ethnicity and socioeconomic status play a role. .

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The term empathy has only existed in English for a little over a hundred years, but the idea of feeling with another person is an old one. Because of its perceived connection to moral behaviour, empathy and its development are of great interest to educators, policy makers, psychologists, and philosophers. Reading children’s literature is often considered important for developing (among other things) children’s ethical and empathic understandings of society and its people. However, claims as to the impact of reading on readers’ ability to become more empathic, tolerant, and better people are divided. While many readers may attribute positive influences that authors and texts have had on shaping their attitudes and actions, there is no guarantee that a desirable affective and cognitive response will follow the reading experience. The complexity of readers and texts refuses to be reduced to simple universal statements about the capacity of narrative empathy to create a particular kind of empathic reader or person: fiction that engages a reader with the emotional plight of a character does not necessarily translate into actions in the real world towards people who are similarly suffering, marginalized, or victimized. This chapter asks: Does children’s literature foster empathy? There are two implicit features of this question: one concerns narrative empathy; the other concerns empathic reader response. The discussion will focus on how a selection of ‘multicultural’ picture books attempts to create narrative empathy by focussing on cultural and spatial differences.

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Bermanite Mn2þMn3þ2 ðPO4Þ2ðOHÞ2 � 4ðH2OÞ is a mixed valent hydrated hydroxy phosphate mineral. The mineral is reddish-brown and occurs in crystal aggregates and as lamellar masses. Bermanite is a common mineral in granitic pegmatites. The chemical composition of bermanite was obtained using EDS techniques. We have studied the molecular structure of bermanite using vibrational spectroscopy. The mineral is characterized by a Raman doublet at 991 and 999 cm-1 attributed to the phosphate stretching mode of two non-equivalent phosphate units. Raman bands at 1071, 1117 and 1142 cm-1 are assigned to the phosphate antisymmetric stretching modes. The hydroxyl stretching spectral region is complex with overlapping bands attributed to water and hydroxyl stretching vibrations. Vibrational spectroscopy proves most useful for the study of the mineral bermanite.

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The techniques of environmental scanning electron microscopy (ESEM) and Raman microscopy have been used to respectively elucidate the morphological changes and nature of the adsorbed species on silver(I) oxide powder, during methanol oxidation conditions. Heating Ag2O in either water vapour or oxygen resulted firstly in the decomposition of silver(I) oxide to polycrystalline silver at 578 K followed by sintering of the particles at higher temperature. Raman spectroscopy revealed the presence of subsurface oxygen and hydroxyl species in addition to surface hydroxyl groups after interaction with water vapour. Similar species were identified following exposure to oxygen in an ambient atmosphere. This behaviour indicated that the polycrystalline silver formed from Ag2O decomposition was substantially more reactive than silver produced by electrochemical methods. The interaction of water at elevated temperatures subsequent to heating silver(I) oxide in oxygen resulted in a significantly enhanced concentration of subsurface hydroxyl species. The reaction of methanol with Ag2O at high temperatures was interesting in that an inhibition in silver grain growth was noted. Substantial structural modification of the silver(I) oxide material was induced by catalytic etching in a methanol/air mixture. In particular, "pin-hole" formation was observed to occur at temperatures in excess of 773 K, and it was also recorded that these "pin- holes" coalesced to form large-scale defects under typical industrial reaction conditions. Raman spectroscopy revealed that the working surface consisted mainly of subsurface oxygen and surface Ag=O species. The relative lack of sub-surface hydroxyl species suggested that it was the desorption of such moieties which was the cause of the "pin-hole" formation.

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Driver sleepiness is a substantial crash risk factor and as such, is a major contributor to crash statistics. A number of individual factors (i.e., psychological factors) have been suggested to influence driving while sleepy. However, few studies have examined the influence of these individual factors for sleepy driving in combination. The current study sought to examine how various demographic factors, attitudes, perceived legitimacy, personality constructs, and risk taking variables were associated with self-reported likelihood of driving sleepy and pulling over and resting when sleepy. The results show that being a younger driver, having positive attitudes towards driving sleepy, and high levels of emotional stability were related to self-reported likelihood of driving sleepy. Whereas, being an older driver and having negative attitudes towards driving sleepy were associated with self-reported likelihood of pulling over and resting when sleepy. Overall, the obtained results suggest that the age and attitudes of the driver have greater influence than personality traits or risk taking factors. Campaigns focused on changing attitudes to reflect the dangerousness of sleepy driving could be important for road safety outcomes.

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Saccharification of sugarcane bagasse pretreated at the pilot-scale with different processes (in combination with steam-explosion) was evaluated. Maximum glucan conversion with Celluclast 1.5 L (15–25 FPU/g glucan) was in the following order: glycerol/HCl > HCl > H2SO4 > NaOH, with the glycerol system achieving ∼100% conversion. Surprisingly, the NaOH substrate achieved optimum saccharification with only 8 FPU/g glucan. Glucan conversions (3.6–6%) obtained with mixtures of endo-1,4-β-glucanase (EG) and β-glucosidase (βG) for the NaOH substrate were 2–6 times that of acid substrates. However, glucan conversions (15–60%) obtained with mixtures of cellobiohydrolase (CBH I) and βG on acidified glycerol substrate were 10–30% higher than those obtained for NaOH and acid substrates. The susceptibility of the substrates to enzymatic saccharification was explained by their physical and chemical attributes. Acidified glycerol pretreatment offers the opportunity to simplify the complexity of enzyme mixtures required for saccharification of lignocellulosics.

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The Norfolk Island population in the South Pacific is primarily the product of recent admixture between a small number of British male and Polynesian female founders. We identified and genotyped 128 Ancestry Informative Markers (AIMs) spread across the autosomes, X/Y chromosomes and mitochondrial DNA genome, to explore and quantify the current levels of genetic admixture in the Norfolk Islanders. On the basis of autosomal AIMs, the population shows mean European and Polynesian ancestry proportions of 88 and 12%, respectively. However, there is a substantial variation between individuals ranging from total European ancestry to near total Polynesian origin. There is a strong correlation between individual genetic estimates of Polynesian ancestry and those derived from the extensive pedigree and genealogical records of Islanders. Also in line with historical accounts, there is a substantial asymmetry in the maternal and paternal origins of the Islanders with almost all Y-chromosomes of European origin whereas at least 25% of mtDNAs appear to have a Polynesian origin. Accurate knowledge of ancestry will be important in future attempts to use the Island population in admixture mapping approaches to find the genes that underlie differences in the risk to some diseases between Europeans and Polynesians.

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Raman and thermo-Raman spectroscopy have been applied to study the mineral formerly known as manasseite now simply renamed as hydrotalcite-2H Mg6Al2(OH)16[CO3]⋅4H2O. The mineral is a member of the homonymous hydrotalcite supergroup. Hydrogen bond distances calculated using a Libowitzky-type empirical function varied between 2.61 and 3.00 Å. Stronger hydrogen bonds were formed by water units as compared to the hydroxyl units. Raman spectroscopy enabled the identification of bands attributed to the hydroxyl units. Two Raman bands at 1059 and 1064 cm-1 are assigned to symmetric stretching modes of the carbonate anion. Thermal treatment shifts these bands to higher wavenumbers indicating a change in the strength of the carbonate bonding.

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Typical migraine is a complex neurological disorder comprised of two main subtypes: migraine with (MA) and without aura (MO). The disease etiology is still unclear, but family studies provide strong evidence that defective genes play an important role. Familial hemiplegic migraine (FHM) is a very rare and severe subtype of MA. It has been proposed that FHM and MA may have a similar genetic etiology. Therefore, genetic studies on FHM provide a useful model for investigating the more prevalent types of typical migraine. FHM in some families has been shown to be caused by mutations in a brain-specific P/Q-type calcium channel alpha1 subunit gene (CACNA1A) on chromosome 19p13. There has also been a report of a CACNA1A mutation being associated with MA in a patient from a family with predominant FHM. We have previously demonstrated suggestive linkage of typical migraine in a large Australian family to the FHM region on chromosome 19p13. These findings suggest that CACNA1A may also be implicated in the etiology of typical migraine in this pedigree. To investigate this possibility, we sequenced two patients carrying the critical susceptibility haplotype surrounding CACNA1A. No disease-causing mutations or polymorphisms were revealed in any of the 47 exons screened. To determine whether the CACNA1A gene was implicated in typical migraine susceptibility in the general Caucasian population, we also analyzed 82 independent pedigrees and a large case control group. We did not detect any linkage or association in these groups and conclude that if CACNA1A plays a role in typical migraine, it does not confer a major effect on the disease.

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We determined the effect of coingestion of caffeine (Caff) with carbohydrate (CHO) on rates of muscle glycogen resynthesis during recovery from exhaustive exercise in seven trained subjects who completed two experimental trials in a randomized, double-blind crossover design. The evening before an experiment subjects performed intermittent exhaustive cycling and then consumed a low-CHO meal. The next morning subjects rode until volitional fatigue. On completion of this ride subjects consumed either CHO [4 g/kg body mass (BM)] or the same amount of CHO + Caff (8 mg/kg BM) during 4 h of passive recovery. Muscle biopsies and blood samples were taken at regular intervals throughout recovery. Muscle glycogen levels were similar at exhaustion [?75 mmol/kg dry wt (dw)] and increased by a similar amount (?80%) after 1 h of recovery (133 ± 37.8 vs. 149 ± 48 mmol/kg dw for CHO and Caff, respectively). After 4 h of recovery Caff resulted in higher glycogen accumulation (313 ± 69 vs. 234 ± 50 mmol/kg dw, P < 0.001). Accordingly, the overall rate of resynthesis for the 4-h recovery period was 66% higher in Caff compared with CHO (57.7 ± 18.5 vs. 38.0 ± 7.7 mmol·kg dw-1·h-1, P < 0.05). After 1 h of recovery plasma Caff levels had increased to 31 ± 11 ?M (P < 0.001) and at the end of the recovery reached 77 ± 11 ?M (P < 0.001) with Caff. Phosphorylation of CaMKThr286 was similar after exercise and after 1 h of recovery, but after 4 h CaMKThr286 phosphorylation was higher in Caff than CHO (P < 0.05). Phosphorylation of AMP-activated protein kinase (AMPK)Thr172 and AktSer473 was similar for both treatments at all time points. We provide the first evidence that in trained subjects coingestion of large amounts of Caff (8 mg/kg BM) with CHO has an additive effect on rates of postexercise muscle glycogen accumulation compared with consumption of CHO alone.

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Online storytelling spaces provide young people who live in rural and remote parts of Australia with an opportunity to develop their personal identities and connect and communicate with other young people. The Australian Broadcasting Corporation’s (ABC’s) rural and regional youth network, Heywire, is such a space (http://www.abc.net.au/heywire/). Heywire invites 16-22 year old Australians who identify as ‘rural’ or ‘regional’ to create an online profile and upload stories about their lives in the form of text, audio, video or photographs. Emerging from my PhD project, this paper describes how rural and regional youth perform their identities through creating stories for the Heywire website, addressing notions of individual and social identities as a sub-theme. Compared with their city counterparts, the youth who live in regional towns or isolated properties have fewer opportunities to socialise with other people their own age. Subsequently computer mediated technologies, particularly the internet, can enable this group of people to connect with each other and develop a sense of community. In this paper I outline how these possibilities exist within an online storytelling space. I describe a number of reasons for young people’s story-sharing on the Heywire website in order to demonstrate the potential for spaces such as this to enable isolated youth to experience a sense of connection and belonging, despite geographical dispersion and physical isolation.

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The study aimed to examine shiftworkers fatigue and the longitudinal relationships that impact on fatigue such as team climate, work life conflict, control of shifts and shift type in shift working nurses. We used a quantitative survey methodology and analysed data with a moderated hierarchical multiple regression. After matching across two time periods 18 months apart, the sample consisted of 166 nurses from one Australian hospital. Of these nurses, 61 worked two rotating day shifts (morning & afternoon/evening) and 105 were rotating shiftworkers who worked three shifts (morning afternoon/evening and nights). The findings suggest that control over shift scheduling can have significant effects on fatigue for both two-shift and three-shift workers. A significant negative relationship between positive team climate and fatigue was moderated by shift type. At both Time 1 and Time 2, work life conflict was the strongest predictor of concurrent fatigue, but over time it was not.

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In early April 1998, the Centre for Disease Control in Darwin was notified of a possible case of dengue which appeared to have been acquired in the Northern Territory. Because dengue is not endemic to the Northern Territory, locally acquired infection has significant public health implications, particularly for vector identification and control to limit the spread of infection. Dengue IgM serology was positive on two occasions, but the illness was eventually presumptively identified as Kokobera infection. This case illustrates the complexity of interpreting flavivirus serology. Determining the cause of infection requires consideration of the clinical illness, the incubation period, the laboratory results and vector presence. Waiting for confirmation of results, before the institution of the public health measures necessary for a true case of dengue, was ultimately justified in this case. This is a valid approach in the Northern Territory, but may not be applicable to areas of Australia with established vectors for dengue. Commun Dis Intell 1998;22:105-107.