933 resultados para FAST-GROWING PLANTATIONS
Resumo:
Complex Event processing (CEP) has emerged over the last ten years. CEP systems are outstanding in processing large amount of data and responding in a timely fashion. While CEP applications are fast growing, performance management in this area has not gain much attention. It is critical to meet the promised level of service for both system designers and users. In this paper, we present a benchmark for complex event processing systems: CEPBen. The CEPBen benchmark is designed to evaluate CEP functional behaviours, i.e., filtering, transformation and event pattern detection and provides a novel methodology of evaluating the performance of CEP systems. A performance study by running the CEPBen on Esper CEP engine is described and discussed. The results obtained from performance tests demonstrate the influences of CEP functional behaviours on the system performance. © 2014 Springer International Publishing Switzerland.
Resumo:
The first decade of the twenty-first century has witnessed further growth in emerging markets, which is significantly influencing the global economic landscape. For the first time in almost two hundred years, it is in this decade that the emerging economies have caught up with, and raced ahead of, the developed ones in terms of gross domestic product. This is a trend that is likely to continue for some time as many of the developed economies struggle to recover from the global financial crisis. In particular, China and India as two fast growing economies are significantly contributing to the world economic growth and are the flag bearers of this transformation. Acknowledged as favourite destinations for global manufacturing (China) and services (India) related outsourcing, both nations offer huge growth opportunities in most products and services. However, in order to sustain their phenomenal economic growth of the past decades, both countries are facing a number of challenges to their human resource management (HRM). From a macro perspective, these issues tend to appear similar (e.g., attraction and retention of talent), but given the significant sociocultural, institutional, political, legal and other differences between the two nations, the logics underpinning the approaches to managing human resources issues appear somewhat different. This chapter therefore aims to highlight the key forces determining the nature of HRM in China and India. The chapter consists of three main sections, in addition to the Introduction and Conclusions.
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The construction of artificial reefs in the oligotrophic seagrass meadows of central Florida Bay attracted large aggregations of fish and invertebrates, and assays of nutrient availability indicated increases in availability of nutrients to sediment microalgae, periphyton, and seagrasses around reefs. An average of 37.8 large (> 10 cm) mobile animals were observed on each small artificial reef. The dominant fish species present was the gray snapper (Lutjanus griseus Linnaeus, 1758). Four yrs after the establishment of the artificial reefs, microphytobenthos abundance was twice as high in reef plots (1.7 ± 0.1 μg chl-a cm-2) compared to control plots (0.9 ± 0.1 μg chl-a cm-2). The accumulation of periphyton on glass periphytometers was four times higher in artificial reef plots (200.1 ± 45.8 mg chl-a m-2) compared to control plots (54.8 ± 6.8 mg chl-a m-2). The seagrass beds surrounding the artificial reefs changed rapidly, from a sparse Thalassia testudinum (Banks & Soland. ex König) dominated community, which persisted at control plots, to a community dominated by Halodule wrightii (Ascherson). Such changes mirror the changes induced in experimentally fertilized seagrass beds in Florida, strongly suggesting that the aggregations of animals attracted by artificial reefs concentrated nutrients in this oligotrophic seascape, favoring the growth of fast-growing primary producers like microphytobenthos and periphyton, and changing the competitively dominant seagrass from slow-growing T. testudinum to faster-growing H. wrightii in the vicinity of the reefs.
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The loss of large-bodied herbivores and/or top predators has been associated with large-scale changes in terrestrial, freshwater, and marine ecosystems around the world. Understanding the consequences of these declines has been hampered by a lack of studies in relatively pristine systems. To fill this gap, I investigated the dynamics of the relatively pristine seagrass ecosystem of Shark Bay, Australia. I began by examining the seagrass species distributions, stoichiometry, and patterns of nutrient limitation across the whole of Shark Bay. Large areas were N-limited, P-limited, or limited by factors other than nutrients. Phosphorus-limitation was centered in areas of restricted water exchange with the ocean. Nutrient content of seagrasses varied seasonally, but the strength of seasonal responses were species-specific. Using a cafeteria-style experiment, I found that fast-growing seagrass species, which had higher nutrient content experienced higher rates of herbivory than slow-growing species that are dominant in the bay but have low nutrient content. Although removal rates correlated well with nutrient content at a broad scale, within fast-growing species removal rates were not closely tied to N or P content. Using a combination of stable isotope analysis and animal borne video, I found that green turtles (Chelonia mydas)—one of the most abundant large-bodied herbivores in Shark Bay—appear to assimilate little energy from seagrasses at the population level. There was, however, evidence of individual specialization in turtle diets with some individuals foraging largely on seagrasses and others feeding primarily on macroalgae and gelatinous macroplankton. Finally, I used exclusion cages, to examine whether predation-sensitive habitat shifts by megagrazers (green turtles, dugongs) transmitted a behavior-mediated trophic cascade (BMTC) between sharks and seagrasses. In general, data were consistent with predictions of a behavior-mediated trophic cascade. Megaherbivore impacts on seagrasses were large only in the microhabitat where megaherbivores congregate to reduce predation risk. My study highlights the importance of large herbivores in structuring seagrass communities and, more generally, suggests that roving top predators likely are important in structuring communities—and possibly ecosystems—through non-consumptive pathways.
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Community ecology seeks to understand and predict the characteristics of communities that can develop under different environmental conditions, but most theory has been built on analytical models that are limited in the diversity of species traits that can be considered simultaneously. We address that limitation with an individual-based model to simulate assembly of fish communities characterized by life history and trophic interactions with multiple physiological tradeoffs as constraints on species performance. Simulation experiments were carried out to evaluate the distribution of 6 life history and 4 feeding traits along gradients of resource productivity and prey accessibility. These experiments revealed that traits differ greatly in importance for species sorting along the gradients. Body growth rate emerged as a key factor distinguishing community types and defining patterns of community stability and coexistence, followed by egg size and maximum body size. Dominance by fast-growing, relatively large, and fecund species occurred more frequently in cases where functional responses were saturated (i.e. high productivity and/or prey accessibility). Such dominance was associated with large biomass fluctuations and priority effects, which prevented richness from increasing with productivity and may have limited selection on secondary traits, such as spawning strategies and relative size at maturation. Our results illustrate that the distribution of species traits and the consequences for community dynamics are intimately linked and strictly dependent on how the benefits and costs of these traits are balanced across different conditions.
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Coral reefs are increasingly threatened by global and local anthropogenic stressors, such as rising seawater temperature and nutrient enrichment. These two stressors vary widely across the reef face and parsing out their influence on coral communities at reef system scales has been particularly challenging. Here, we investigate the influence of temperature and nutrients on coral community traits and life history strategies on lagoonal reefs across the Belize Mesoamerican Barrier Reef System (MBRS). A novel metric was developed using ultra-high-resolution sea surface temperatures (SST) to classify reefs as enduring low (lowTP), moderate (modTP), or extreme (extTP) temperature parameters over 10 years (2003 to 2012). Chlorophyll-a (chl a) records obtained for the same interval were employed as a proxy for bulk nutrients and these records were complemented with in situ measurements to "sea truth" nutrient content across the three reef types. Chl a concentrations were highest at extTP sites, medial at modTP sites and lowest at lowTP sites. Coral species richness, abundance, diversity, density, and percent cover were lower at extTP sites compared to lowTP and modTP sites, but these reef community traits did not differ between lowTP and modTP sites. Coral life history strategy analyses showed that extTP sites were dominated by hardy stress-tolerant and fast-growing weedy coral species, while lowTP and modTP sites consisted of competitive, generalist, weedy, and stress-tolerant coral species. These results suggest that differences in coral community traits and life history strategies between extTP and lowTP/modTP sites were driven primarily by temperature differences with differences in nutrients across site types playing a lesser role. Dominance of weedy and stress-tolerant genera at extTP sites suggests that corals utilizing these two life history strategies may be better suited to cope with warmer oceans and thus may warrant further protective status during this climate change interval.
Data associated with this project are archived here, including:
-SST data
-Satellite Chl a data
-Nutrient measurements
-Raw coral community survey data
For questions contact Justin Baumann (j.baumann3
Resumo:
Tourism remains one of the most fast growing and important industries in the world. It is hard to underestimate the importance and the spectrum of the benefits that tourism provides. On the other hand, nowadays, the increasing growth of tourism poses a range of challenges and problems that need to be solved. These challenges resonate in the emergence of the so called 'alternative' or sustainable forms of tourism, which deem to be an antidote against the harms the traditional forms of tourism cause to the environment and local communities. These new forms of tourism, among which is creative tourism, are reinforced by the new breed of tourists, who are no longer satisfied with the static offer of tourism but rather prefer the dynamic one. The present research shows on the case of Óbidos the potential of creative tourism to meet these new needs of modern tourists while also solving number of problems that many destinations face, namely seasonality in tourism, as well as how creative tourism contributes to the sustainable development of tourism.
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Aquaculture is a fast-growing industry contributing to global food security and sustainable aquaculture, which may reduce pressures on capture fisheries. The overall objective of this thesis was to look at the immunostimulatory effects of different aspects of aquaculture on the host response of the edible sea urchin, Paracentrotus lividus, which are a prized delicacy (roe) in many Asian and Mediterranean countries. In Chapter 1, the importance of understanding the biology, ecology, and physiology of P. lividus, as well as the current status in the culture of this organism for mass production and introducing the thesis objectives for following chapters is discussed. As the research commenced, the difficulties of identifying individuals for repeat sampling became clear; therefore, Chapter 2 was a tagging experiment that indicated PIT tagging was a successful way of identifying individual sea urchins over time with a high tag retention rate. However, it was also found that repeat sampling via syringe to measure host response of an individual caused stress which masked results and thus animals would be sampled and sacrificed going forward. Additionally, from personal observations and discussion with peers, it was suggested to look at the effect that diet has on sea urchin immune function and the parameters I measured which led to Chapter 3. In this chapter, both Laminaria digitata and Mytilus edulis were shown to influence measured immune parameters of differential cell counts, nitric oxide production, and lysozyme activity. Therefore, trials commencing after Trial 5 in Chapter 4, were modified to include starvation in order to remove any effect of diet. Another important aspect of culturing any organism is the study of their immune function and its response to several immunostimulatory agents (Chapter 4). Zymosan A was shown to be an effective immunostimulatory agent in P. lividus. Further work on handled/stored animals (Chapter 5) showed Zymosan A reduced the measured levels of some immune parameters measured relative to the control, which may reduce the amount of stress in the animals. In Chapter 6, animals were infected with Vibrio anguillarum and, although V. anguillarum, impacted immune parameters of P. lividus, it did not cause mortality as predicted. Lastly, throughout this thesis work, it was noted that the immune parameters measured produced different values at different times of the year (Chapter 7); therefore, using collated baseline (control) data, results were compiled to observe seasonal effects. It was determined that both seasonality and sourcing sites influenced immune parameter measurements taken at different times throughout the year. In conclusion, this thesis work fits into the framework of development of aquaculture practices that affect immune function of the host and future research focusing on the edible sea urchin, P. lividus.
Resumo:
The cold-water coral Lophelia pertusa is one of the few species able to build reef-like structures and a 3-dimensional coral framework in the deep oceans. Furthermore, deep cold-water coral bioherms may be among the first marine ecosystems to be affected by ocean acidification. Colonies of L. pertusa were collected during a cruise in 2006 to cold-water coral bioherms of the Mingulay reef complex (Hebrides, North Atlantic). Shortly after sample collection onboard these corals were labelled with calcium-45. The same experimental approach was used to assess calcification rates and how those changed due to reduced pH during a cruise to the Skagerrak (North Sea) in 2007. The highest calcification rates were found in youngest polyps with up to 1% d-1 new skeletal growth and average rates of 0.11±0.02% d-1±S.E.). Lowering pH by 0.15 and 0.3 units relative to the ambient level resulted in calcification being reduced by 30 and 56%. Lower pH reduced calcification more in fast growing, young polyps (59% reduction) than in older polyps (40% reduction). Thus skeletal growth of young and fast calcifying corallites suffered more from ocean acidification. Nevertheless, L. pertusa exhibited positive net calcification (as measured by 45Ca incorporation) even at an aragonite saturation state below 1.
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This dissertation examines the drivers and implications of international capital flows. The overarching motivation is the observation that countries not at the centre of global financial markets are subject to considerable spillovers from centre countries, notably from their monetary policy. I present new empirical evidence on the determinants of the observed patterns of international capital flows and monetary policy spillovers, and study their effect on both financial markets and the real economy. In Chapter 2 I provide evidence on the determinants of a puzzling negative correlation observed between productivity growth and net capital inflows to developing and emerging market economies (EMEs) since 1980. By disaggregating net capital inflows into their gross components, I show that this negative correlation is explained by capital outflows related to purchases of very liquid assets from the fastest growing countries. My results suggest a desire for international portfolio diversification in liquid assets by fast growing countries is driving much of the original puzzle. In the reminder of my dissertation I pivot to study the foreign characteristics that drive international capital flows and monetary policy spillovers, with a particular focus on the role of unconventional monetary policy in the United States (U.S.). In Chapter 3 I show that a significant portion of the heterogeneity in EMEs' asset price adjustment following the quantitative easing operations by the Federal Reserve (the Fed) during 2008-2014 can be explained by the degree of bilateral capital market frictions between these countries and the U.S. This is true even after accounting for capital controls, exchange rate regimes, and domestic monetary policies. Chapter 4, co-authored with Michal Ksawery Popiel, studies unconventional monetary policy in a small open economy, looking specifically at the case of Canada since the global financial crisis. We quantify the effect Canadian unconventional monetary policy shocks had on the real economy, while carefully controlling for and quantifying spillovers from U.S. unconventional monetary policy. Our results indicate that the Bank of Canada's unconventional monetary policy increased Canadian output significantly from 2009-2010, but that spillovers from the Fed's policy were even more important for increasing Canadian output after 2008.
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This thesis examines the rise and decline of the New Left in Toronto from 1958 to 1985. It argues that New Leftism — whose three leading ideals were self-management, national liberation, and community — arose as much from the Old Left as it did from the peace movement. In contrast to earlier readings that interpret the New Left narrowly — essentially, as the combined forces of the white student and peace movements evident mainly on university campuses — this thesis documents the extent to which New Leftism, interpreted as a political formation, provided a framework for a diversity of radical social movements, especially feminism, Black Power, gay liberation, resistance to the capitalist redevelopment of the city, and transnational solidarity. It also questions a declensionist narrative that adopts a “decadal” approach to the radicalism of the sixties, according to which 1970 spelled the end of “60s” radicalism. Quite the contrary, this thesis argues: in Toronto, it would be truer to say that 1970s were “the sixties,” in that only in this later decade did many New Left movements attain their full maturity. New Leftists successfully challenged a host of institutions, sometimes with permanent effects. The educational system was transformed. Cultural institutions and practices were revolutionized. Questions of race and gender, once peripheral to the left, were made central to it. Democratic community institutions became far more powerful. A token of the strength and durability of the New Left in Toronto was the extent to which it remained the bête noir of a series of other radical groups upholding the model of the vanguard communist party — which challenged the New Leftists’ prominence but many members of which often wound up agreeing with their positions. It was only in the early 1980s, with the ascent of a new right, that Toronto’s New Left unmistakably entered a period of decline. Yet, even then, many of its key themes were picked up by fast-growing anarchist and socialist feminist currents. Far from constituting a minor phenomenon, Toronto’s New Left, one of the largest movements for social justice in Canadian history, bequeathed to its progressive successors an imposing legacy of struggle and cultural achievements. It is the purpose of this thesis to evaluate, both critically and sympathetically, the extent to which the New Left attained its radical ambition.
Resumo:
Literature describing the notion and practice of business models has grown considerably over the last few years. Innovative business models appear in every sector of the economy challenging traditional ways of creating and capturing value. However, research describing the theoretical foundations of the field is scarce and many questions still remain. This article examines business models promoting various aspects of sustainable development and tests the explanatory power of two theoretical approaches, namely the resource based view of the firm and transaction cost theory regarding their emergence and successful market performance. Through the examples of industrial ecology and the sharing economy the author shows that a sharp reduction of transaction costs (e.g. in the form of internet based systems) coupled with resources widely available but not utilised before may result in fast growing new markets. This research also provides evidence regarding the notion that these two theoretical approaches can complement each other in explaining corporate behaviour.
Different aspects to consider during kiln drying of Vochysia guatemalensis Donn Sm. Wood (Cebo/Mayo)
Resumo:
Vochysia guatemalensis Donn Sm. wood is currently provided from plantations in several regions of Costa Rica. This wood presents several problems during the drying process such as high variability in the moisture content and high incidence of later defects. The objective of this study was to investigate the causes of this variation and defect developments. It was considered climate condition or precedence, grain pattern, drying schedule, boards position in relation to height and distance from to pith and heartwood presence. The main factors affecting the moisture variability and drying defects were found to be: high initial moisture content variability in different parts of the tree, climate condition, and improper drying programs. Besides, there are recommendations to consider before starting the drying process. Thus a better wood quality in relation to moisture content variability and the presence of defects can be obtained after drying process.
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Among bivalve species, the Pacific oyster, Crassostrea gigas, is the most economically important bivalve production over the world. Today, C. gigas is subject to an important production effort that leads to an intensive artificial selection. Larval stage is relatively unknown, specifically in a domestication context. Genetic consequence of artificial selection is still at a preliminary study. We aimed to tackle the consequence of inconscient domestication on the variance reproductive success focusing on larval stage, keystone of the life cycle. We studied two kinds of specific selective processes that common hatchery rearing practices exert : the effect of discarding the smallest larvae on genetic diversity and the artificial environment rearing effect via the temperature providing a contrast resembling wild versus hatchery conditions (20 and 26°C). In order to monitor the effect of the selection of fast growing larvae by sieving, growth variability and genetic diversity in a larval population descended from a factorial breeding was studied. We used a mixed-family approach to reduce potentially confounding environmental biais. The retrospective assignment of individuals to family groups has been performed using a three microsatellite markers set. Two different rearing were carried out in parallel. For three (replicates) 50-l tanks, the smallest larvae were progressively discarded by selective sieving, whereas for the three others no selective sieving was performed. The intensity of selective sieving was adjusted so as to discard 50% of the larvae over the whole rearing period in a progressive manner. As soon as the larvae reached the pediveliger stage, ready to settle larvae were sampled for genetic analysis. Regarding the artificial environment rearing effect via the temperature, we used a similar mixed-family approach. The progeny from a factorial breeding design was divided as follows: three (replicates) 50-l tanks were dedicaced to a rearing at 26°C versus 20°C for three others 50-l tanks. The whole size variability was preserved for this experiment. Individual growth measurements for larvae genetically identified have been performed at days 22 and 30 after fertilization for both conditions. In a same way, we collected individual measurements for genotyped juvenile oysters (80 days after fertilization). At a phenotypic scale, relative survival and settlement success for larvae with sieving were higher. Sieving appears as a time-saving process associated with a better relative survival ratio. But in the same time, our results confirm that a significant genetic variability exist for early developmental traits in the Pacific oyster. This is congruent with the results already obtained that investigated genetic variability and genetic correlations in early life-history traits of Crassostrea gigas. Discarding around 50% of the smallest larvae can lead to significant selection at the larval stage.
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Betanodavirus infections have a significant impact through direct losses and trade restrictions for aquaculture sectors in Australia. The giant grouper, Epinephelus lanceolatus, is a high-value, fast-growing species with significant aquaculture potential. With subacute to chronic mortalities reported from a commercial aquaculture facility in northern Queensland, the viral nervous necrosis in the affected fish was confirmed using a RT-qPCR followed by virus isolation using the SSN-1 cell line. The RNA1 and RNA2 segments were sequenced and nucleotide sequences were compared with betanodavirus sequences from GenBank. Phylogenetic analysis revealed that both these sequences clustered with sequences representing red spotted grouper nervous necrosis virus genotype and showed high sequence identity to virus sequences affecting other grouper species. This is the first report confirming infection by betanodavirus in E. lanceolatus from Australia with successful isolation of the virus in a cell culture system, and analysis of nearly full length RNA1 and RNA2 sequences.