988 resultados para 173-1065


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Approaches to quantify the organic carbon accumulation on a global scale generally do not consider the small-scale variability of sedimentary and oceanographic boundary conditions along continental margins. In this study, we present a new approach to regionalize the total organic carbon (TOC) content in surface sediments (<5 cm sediment depth). It is based on a compilation of more than 5500 single measurements from various sources. Global TOC distribution was determined by the application of a combined qualitative and quantitative-geostatistical method. Overall, 33 benthic TOC-based provinces were defined and used to process the global distribution pattern of the TOC content in surface sediments in a 1°x1° grid resolution. Regional dependencies of data points within each single province are expressed by modeled semi-variograms. Measured and estimated TOC values show good correlation, emphasizing the reasonable applicability of the method. The accumulation of organic carbon in marine surface sediments is a key parameter in the control of mineralization processes and the material exchange between the sediment and the ocean water. Our approach will help to improve global budgets of nutrient and carbon cycles.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A uniform chronology for foraminifera-based sea surface temperature records has been established in more than 120 sediment cores obtained from the equatorial and eastern Atlantic up to the Arctic Ocean. The chronostratigraphy of the last 30,000 years is mainly based on published d18O records and 14C ages from accelerator mass spectrometry, converted into calendar-year ages. The high-precision age control provides the database necessary for the uniform reconstruction of the climate interval of the Last Glacial Maximum within the GLAMAP-2000 project.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The exponential growth of studies on the biological response to ocean acidification over the last few decades has generated a large amount of data. To facilitate data comparison, a data compilation hosted at the data publisher PANGAEA was initiated in 2008 and is updated on a regular basis (doi:10.1594/PANGAEA.149999). By January 2015, a total of 581 data sets (over 4 000 000 data points) from 539 papers had been archived. Here we present the developments of this data compilation five years since its first description by Nisumaa et al. (2010). Most of study sites from which data archived are still in the Northern Hemisphere and the number of archived data from studies from the Southern Hemisphere and polar oceans are still relatively low. Data from 60 studies that investigated the response of a mix of organisms or natural communities were all added after 2010, indicating a welcomed shift from the study of individual organisms to communities and ecosystems. The initial imbalance of considerably more data archived on calcification and primary production than on other processes has improved. There is also a clear tendency towards more data archived from multifactorial studies after 2010. For easier and more effective access to ocean acidification data, the ocean acidification community is strongly encouraged to contribute to the data archiving effort, and help develop standard vocabularies describing the variables and define best practices for archiving ocean acidification data.

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Technology imbued m-marketing systems influence the consumptive lives of citizens, by facilitating anytime, anywhere business-to-consumer interactions. Business pundits’ enthusiasm towards mobile services (m-services) has been driven by the promise of a marketspace context involving seamless, business-to-consumer interactions that can be simultaneously impulse-driven, highly entertaining and omnipresent. Arguably, gambling too is impulse-driven, exciting and easily accessible. An important question that needs to be addressed is: how the convergence of mobile technology and gambling will impact the millennial consumer. The authors address this question by examining the contextually bounded interactions between internal and external factors that make mobile phone users potentially vulnerable during m-gambling interactions. By examining key themes that describe the convergence of m-technology and gambling, we clarify the experiential nature of m-gambling and its relationship to consumer vulnerability.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Through adolescence, young people are at an exciting point of their maturation. On the whole they are thoughtful, caring and responsible people. In many ways they are just beginning to make valuable contributions to the society they will soon be steering. They are critical and reflective, and they are passionate and energetic. We have discovered in earlier chapters the types of physical and cognitive changes and developments that confront adolescents. In this chapter we will explore emotional and moral development and allied issues of resilience and vulnerability. The emotional dimension of adolescence can tie in with several other issues that extend from aloneness, loneliness and alienation. We will introduce key theory and theorists in the field of emotional and moral development (such as Kohlberg). Some adolescents have a traumatic time (as do people of all ages and phases of life) and this book wouldn’t be whole without a brief discussion of the types of issues that emerge as young people in the throes of developing their moral and emotional perspective of the world are dealt life challenges.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Nearly 500 secondary students in 24 classes were surveyed and four students in each class interviewed concerning their approaches to learning and perceptions of their classroom environment. While interviewed students with deep approaches to learning generally demonstrated a more sophisticated understanding of the learning opportunities offered to them than did students with surface approaches, teaching strategies also influenced students' perceptions. When teachers focused strongly on actively engaging students and creating a supportive environment, students with both deep and surface approaches focused on student-centred aspects of the class. In contrast, when traditional expository teaching methods were used exclusively, students with deep and surface approaches both focused on transmission and reproduction.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The outcomes of a two-pronged 'real-world' learning project, which aimed to expand the views of pre-service teachers about learning, pedagogy and diversity, will be discussed in this paper. Seventy-two fourth-year and 22 first-year students, enrolled in a Bachelor of Education degree in Queensland, Australia, were engaged in community sites outside of university lectures, and separate from their practicum. Using Butin's conceptual framework for service learning, we show evidence that this approach can enable pre-service teachers to see new realities about the dilemmas and ambiguities of performing as learners and as teachers. We contend that when such 'real-world' experiences have different foci at different times in their four-year degree, pre-service teachers have more opportunities to develop sophisticated understandings of pedagogy in diverse contexts for diverse learners.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background First aid given immediately after a motor vehicle crash can have considerable benefits. Less understood however is first aid training as a prevention strategy for reducing risk-taking. A first step is to understand whether first aid skills are associated with risk-taking and injury experiences. Further, students and teachers who undergo or deliver such training offer important perspectives about implementation. Aims The research has two aims: (i) to identify whether first aid knowledge is associated with road risk-taking and injury and (ii) to examine teachers’ and students’ experiences of first aid activities within a school-based injury prevention and control program. Method Participants were 173 Year 9s (47% male) who completed a survey which included demographic information, first aid knowledge and risk-taking behaviour and injury experiences. Focus groups were held with 8 teachers who delivered, and 70 students who participated in, a school-based injury prevention and control program. Results Results showed a relationship between greater first aid knowledge and reduced engagement in risk-taking and injury experiences. Both students and teachers reported favourably on first aid however teachers also acknowledged challenges in delivering practical activities. Discussion & Conclusion It appears that first aid can be implemented within the school setting, particularly at the Year 9 level, and that both students and teachers involved in such training identify multiple benefits and positive experiences with first aid training. In addition, the findings suggest that first aid knowledge could be an important part of a prevention program.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Sexually transmitted chlamydial infection initially establishes in the endocervix in females, but if the infection ascends the genital tract, significant disease, including infertility, can result. Many of the mechanisms associated with chlamydial infection kinetics and disease ascension are unknown. We attempt to elucidate some of these processes by developing a novel mathematical model, using a cellular automata–partial differential equation model. We matched our model outputs to experimental data of chlamydial infection of the guinea-pig cervix and carried out sensitivity analyses to determine the relative influence of model parameters. We found that the rate of recruitment and action of innate immune cells to clear extracellular chlamydial particles and the rate of passive movement of chlamydial particles are the dominant factors in determining the early course of infection, magnitude of the peak chlamydial time course and the time of the peak. The rate of passive movement was found to be the most important factor in determining whether infection would ascend to the upper genital tract. This study highlights the importance of early innate immunity in the control of chlamydial infection and the significance of motility-diffusive properties and the adaptive immune response in the magnitude of infection and in its ascension.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Investigated the psychometric properties of the original and alternate sets of the Trail Making Test (TMT) and the Controlled Oral Word Association Test (COWAT; A. L. Benton and D. Hamsher, 1978) in 50 orthopedic and 15 closed head injured (1 yr after trauma) patients (aged 15–59 yrs). Although the alternate forms of both measures proved to be stable and consistent with each other in both groups, only the parallel sets of TMT reliably discriminated the clinical group from controls. Practice effects in the head injured were significant only for Trail B of TMT. Factor analysis of the control group's results identified Verbal Knowledge as a major contributor to performance on COWAT, whereas TMT was more dependent on Rapid Visual Search and Visuomotor Sequencing.