977 resultados para source-sink relationship


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The nature of the climate–carbon cycle feedback depends critically on the response of soil carbon to climate, including changes in moisture. However, soil moisture–carbon feedback responses have not been investigated thoroughly. Uncertainty in the response of soil carbon to soil moisture changes could arise from uncertainty in the relationship between soil moisture and heterotrophic respiration. We used twelve soil moisture–respiration functions (SMRFs) with a soil carbon model (RothC) and data from a coupled climate–carbon cycle general circulation model to investigate the impact of direct heterotrophic respiration dependence on soil moisture on the climate carbon cycle feedback. Global changes in soil moisture acted to oppose temperature‐driven decreases in soil carbon and hence tended to increase soil carbon storage. We found considerable uncertainty in soil carbon changes due to the response of soil respiration to soil moisture. The use of different SMRFs resulted in both large losses and small gains in future global soil carbon stocks, whether considering all climate forcings or only moisture changes. Regionally, the greatest range in soil carbon changes across SMRFs was found where the largest soil carbon changes occurred. Further research is needed to constrain the soil moisture–respiration relationship and thus reduce uncertainty in climate–carbon cycle feedbacks. There may also be considerable uncertainty in the regional responses of soil carbon to soil moisture changes since climate model predictions of regional soil moisture changes are less coherent than temperature changes.

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We test the method of Lockwood et al. [1999] for deriving the coronal source flux from the geomagnetic aa index and show it to be accurate to within 12% for annual means and 4.5% for averages over a sunspot cycle. Using data from four solar constant monitors during 1981-1995, we find a linear relationship between this magnetic flux and the total solar irradiance. From this correlation, we show that the 131% rise in the mean coronal source field over the interval 1901-1995 corresponds to a rise in the average total solar irradiance of {\Delta}I = 1.65 +/- 0.23 Wm^{-2}.

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The present study examines three competing models of morphosyntactic transfer in third language (L3) acquisition, examining the particular domain of the feature configuration of embedded T in L3 Brazilian Portuguese (BP) at the initial stages and then through development. The methodology alternates Spanish and English as the L1 and L2 to tease apart the source of transfer to L3 BP. Results from a scalar grammaticality acceptability task show unequivocal transfer of Spanish irrespective of Spanish’s status as an L1 or L2. The data thus support the Typological Primacy Model (Rothman 2010, 2011, 2013a, 2013b), which proposes that multilingual transfer is selected by factors related to comparative structural similarity. Given that Spanish transfer at the L3 initial stages creates the need for feature reconfiguration to converge on the target BP grammar, the second part of this chapter examines the developmental consequences of what the TPM models in cases of non-facilitative initial transfer, that is, the developmental path of feature reconfiguration of embedded T in L3 BP by English/Spanish bilinguals. Given what these data reveal, we address the role of regressive transfer as a correlate of L3 proficiency gains.

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Recent research suggests Eurasian snow-covered area (SCA) influences the Arctic Oscillation (AO) via the polar vortex. This could be important for Northern Hemisphere winter season forecasting. A fairly strong negative correlation between October SCA and the AO, based on both monthly and daily observational data, has been noted in the literature. While reproducing these previous links when using the same data, we find no further evidence of the link when using an independent satellite data source, or when using a climate model.

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The Granada ignimbrite, an Upper Miocene volcanic unit from the northern Puna, previously has been interpreted as an extensive ignimbrite (>2300 km(2)) associated with eruptions from the Vilama caldera (trap-door event). On the basis of new data, we revise its correlation and redefine the unit as a compound, high aspect ratio ignimbrite, erupted at approximately 9.8 Ma. Calculated volumes (similar to 100 km(3)) are only moderate in comparison with other large volume (>1000 km(3)) ignimbrites that erupted approximately 2-6 m.y. later in the region (e.g. Vilama, Panizos, Atana). Six new volcanic units are recognized from sequences previously correlated with Granada (only one sourced from the same center). Consequently, the area ascribed to the Granada ignimbrite is substantially reduced (630 km(2)), and links to the Vilama caldera are not supported. Transport directions suggest the volcanic source for the Granada ignimbrite corresponds to vents buried under younger (>= 7.9-5 Ma) volcanic rocks of the Abra Granada volcanic complex. Episodes of caldera collapse at some stage of eruption are likely, though their nature and timing cannot be defined from available data. The eruption of the Granada ignimbrite marks the onset of a phase of large volume (caldera-sourced) volcanism in the northern Puna. (C) 2007 Elsevier Ltd. All rights reserved.

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In Western research, cruelty to animals in childhood has been associated with comorbid conduct problems and with interpersonal violence in later life. However, there is little understanding of the etiology of cruelty to animals, and what in the child's life may require attention if the chain linking animal cruelty and later violence is to be broken. The study reported in this paper investigated the association between parent-reported cruelty to animals, and parent- and self-reported psychological strengths and weaknesses in a sample of 379 elementary school children in an Eastern context, Malaysia. No gender differences were found in relation to cruelty to animals or psychological problems, as assessed with the Strengths and Difficulties Questionnaire (SDQ). However, there were different predictors of cruelty to animals for boys and girls. Regression analyses found that for boys, parent-reported hyperactivity was a unique predictor of Malicious and Total Cruelty to animals. For girls, self-reported conduct problems was a unique predictor of Typical Cruelty to animals. Parent-reported total difficulties were associated with Typical, Malicious, and Total Cruelty to animals. We suggest that routine screening of children with an instrument such as the SDQ may help to detect those children who may need to undergo further assessment and perhaps intervention to break the chain linking childhood cruelty to animals and later conduct problems.

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The research reported in this paper investigated the relationship between information usage and individual ticket-purchasing activity of Opera Australia customers in relation to specific Opera Australia products, namely, operetta and opera. The results provide some support for the notion that consumers of operetta and opera can be distinguished on the basis of their different behaviour in some areas. However, there is substantial “crossing-over” or inconsistency in the data. Longevity of association with the art-form, and purchasing tickets to both types of productions, tended to be related to increased reliance on information sources closer to Opera Australia.

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Purpose: An ongoing concern with the evaluation of auditory processing disorders is the extent that assessment instruments are influenced by higher order cognitive functions. This study examined the relationship between verbal working memory and performance on the Test for Auditory Processing Disorders in Children--Revised (SCAN-C; Keith, 2000b) in children with specific language impairment (SLI) and typically developing (TD) children.

Method: Sixteen children with SLI and 16 TD children ages 8/4 to 11 years participated in the study. The children were presented with the SCAN-C and tests measuring verbal working memory.

Results:
Initial comparisons revealed that the SLI group obtained significantly lower scores than the TD group on the SCAN-C. However, after controlling for verbal working memory, significant differences between the 2 groups were no longer observed. Correlational analyses revealed that the composite score from the SCAN-C was related to all tests assessing verbal working memory.

Conclusions:
Performance on the SCAN-C may be related to working memory functioning. As a consequence, it is unclear whether difficulty on this task should be viewed as a problem with auditory processing or a problem with verbal working memory.

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Objective: Family characteristics (relationship quality, parental behaviors, and attitudes relating to alcohol use) are known to influence alcohol use in the mid-teen years, and there is evidence that family characteristics have different influences on mid-teen girls versus boys. This study examined child gender differences in the association of family relationship quality, parental disapproval of children's alcohol use, and parental alcohol use with early adolescent alcohol use.

Method: Grade 6 and 8 students (modal age 11 and 13, respectively; N = 6,837; 52.6% female) were recruited from 231 schools across three Australian states. Hypotheses were tested using two-level ordinal logistic regression (individuals nested within schools). The main dependent measure was lifetime frequency of early adolescent alcohol consumption. Independent variables included mother's/father's alcohol use, closeness, conflict, and disapproval of adolescent alcohol use. Control variables included sensation seeking, peer alcohol use, and socioeconomic disadvantage.

Results: The key findings were that for the young age group (Grade 6), emotional closeness to the parent of the opposite sex was protective. Family conflict was associated with females' drinking in both age groups but not males' drinking.

Conclusions: There was evidence of gender differences in the epidemiology of family relationship quality and early alcohol use. Social developmental models may need revision to account for these child gender differences. Gender-specific family dynamics may be an important consideration for family-oriented prevention strategy.

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The basic differences between marketing managers and their technically trained counterpart managers [e.g., research and development (R&D), engineering, and manufacturing managers] in terms of work experience, training, and differing decision-making styles have often been suggested as a source of conflict, which acts as a barrier to effective working relationships and integration during new product development (NPD) work. In this paper, we empirically explore this issue by developing and testing a model of psychosocial differences (thought worlds and psychological distance) between the two groups of managers and their effect on communication, trust, and relationship effectiveness during NPD projects. We find that while thought world differences do still matter, it was from a marketing perspective that they had a stronger effect. These findings have implications for top management trying to manage the functional manager interface during NPD projects. We propose a semi-formalized approach to relationship building that may speed up the acquisition of social data that is often necessary to elevate working relationships to trusting ones and improve the efficiency of NPD work. Our model is tested using data from two samples, 184 technically trained managers and 145 marketing managers from Australian companies involved in NPD work.

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During the reproductive season, sea turtles use a restricted area in the vicinity of their nesting beaches, making them vulnerable to predation. At Raine Island (Australia), the highest density green turtle Chelonia mydas rookery in the world, tiger sharks Galeocerdo cuvier have been observed to feed on green turtles, and it has been suggested that they may specialise on such air-breathing prey. However there is little information with which to examine this hypothesis. We compared the spatial and temporal components of movement behaviour of these two potentially interacting species in order to provide insight into the predator-prey relationship. Specifically, we tested the hypothesis that tiger shark movements are more concentrated at Raine Island during the green turtle nesting season than outside the turtle nesting season when turtles are not concentrated at Raine Island. Turtles showed area-restricted search behaviour around Raine Island for ~3–4 months during the nesting period (November–February). This was followed by direct movement (transit) to putative foraging grounds mostly in the Torres Straight where they switched to area-restricted search mode again, and remained resident for the remainder of the deployment (53–304 days). In contrast, tiger sharks displayed high spatial and temporal variation in movement behaviour which was not closely linked to the movement behaviour of green turtles or recognised turtle foraging grounds. On average, tiger sharks were concentrated around Raine Island throughout the year. While information on diet is required to determine whether tiger sharks are turtle specialists our results support the hypothesis that they target this predictable and plentiful prey during turtle nesting season, but they might not focus on this less predictable food source outside the nesting season.

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Smartphone applications are getting more and more popular and pervasive in our daily life, and are also attractive to malware writers due to their limited computing source and vulnerabilities. At the same time, we possess limited understanding of our opponents in cyberspace. In this paper, we investigate the propagation model of SMS/MMS-based worms through integrating semi-Markov process and social relationship graph. In our modeling, we use semi-Markov process to characterize state transition among mobile nodes, and hire social network theory, a missing element in many previous works, to enhance the proposed mobile malware propagation model. In order to evaluate the proposed models, we have developed a specific software, and collected a large scale real-world data for this purpose. The extensive experiments indicate that the proposed models and algorithms are effective and practical. © 2014 Elsevier Ltd. All rights reserved.

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We reconstructed the nutrient source for egg synthesis by sampling Black-headed Gull (Larus ridibundus) eggs for yolk, analyzing their carbon stable isotope ratio, and comparing that to hatchling down. Most of the variation in carbon stable isotope ratio was explained by differences between nests, the within-nest variation being explained by laying order. These data indicate significant differences in diet choice between individual females and changes in food choice or body-store dynamics during egg laying. Among-egg variation in the carbon stable isotope ratios of the yolk were closely reflected in the hatchling down, on average down being enriched by 3.1‰ δ13C relative to yolk. Our findings support the contention that pre-laying female diets can be evaluated from hatchling down.

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Five years ago, Coca-Cola Brasil launched a program named “Coletivo Project”, with the purpose to enjoy an opportunity of increase on the potential consumption power of the low-income pyramid population that lived on the “favelas”. At the same time, it had the objective to offer to them a social and financial impact, which is a trust on the future, the first job for the young adults’ participant of this program and an increase on their family source of revenues, through salaries. This was possible because through Coletivo Project, Coca-Cola identified the assets they have through its value chain, focusing on its competencies, such as retail, merchandising and logistics to apply them on courses to teach the young people of the communities and, as a result, form them to be able to find their new jobs. Internal indicators followed in a monthly basis by Coca-Cola demonstrated that the communities that had the presence of Coletivos, in comparison to those without Coletivos, had social and financial impacts. The social was the fact that the young formed started to have more confidence on their future and felt with a higher self-stem to apply for and obtain their first job. On the financial aspect, they were benefit through the increasing of their revenues and also their families and Coca-Cola had an increase on sales, when compared to a community without a Coletivo Project installed. This dissertation seeks to identify the current relationship between Coca-Cola and the communities, through the Coletivo Project classes performed on the NGOs located at this places, in order to identify opportunities for improvement the benefits and the impacts (financial and social) on the NGOs, communities and all stakeholders of this project. This dissertation examines this relationship, through presence interviews performed on four NGOs selected, and located on four of the twenty communities, that are participants of the Coletivo Project on Rio de Janeiro city. These interviews performed with the students, representatives and educators of these NGOs. The covered period of the interviews ranges from April 2014 to August 2014. This dissertation draws on first-hand qualitative empirical evidence gathered through extensive fieldwork. The main findings among possibilities for improvement by Coca-Cola are: • Implement new courses, beyond those existent at Coca-Cola (Retail, Logistics, etc.). • Increase the content of the employment module of Coletivo classes, focusing on improving educational, cultural, economic, political, social and professional life. • Increase the scale, through the quantity of positions on the Retail Coletivo classes. • Develop cultural and sports events with the communities. • Support the points of sales, participant of the practical classes of the Coletivo Retail, with refrigerators and furniture with the Coca-Cola logo. • Provide coffee breaks and meals during the Coletivo classes, using Coca-Cola beverages and partners for food items, developing the nutrition platform of the company and filling a need of the students. • Perform a research with all stakeholders related to this Project, including those students and mothers that are not participant of the Coletivo, in order to listen to them, understand their needs, and offer solutions to fulfill these gaps. and on the side of the • Perform partnerships with educational institutions to make viable other type of courses, more technical, but that have a relation with the core business of Coca-Cola Brasil, such as marketing. • Implement the Coca-Cola University, already existed at the Company. • Create courses or activities focused on the children. Regarding the impossibilities, the findings are: • Improve the basic sanitation of the communities. • Improve the safety on the communities. • Provide a home to those do not have. • Implement courses that have no relationship with Coca-Cola business and expertise, such as gastronomy. However, Coca-Cola can influence stakeholders on that. The results suggest to executives of Coca-Cola that a deep and a qualitative research on the communities of Brazil, in order to listen young people, educators, mothers, partners that offer jobs, from Coletivo and out of the project, is mandatory, to understand their needs, dreams, complains and offer valuable solutions to all.