855 resultados para Salmons, Joe: Accentual change and language contact
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A solid body of empirical, experimental and theoretical evidence accumulated over recent years indicated that freshwater plankton experienced advance in phenology in response to climate change. Despite rapidly growing evidence for phenological changes, we still lack a comprehensive understanding of how climate change alters plankton phenology in freshwater. To overcome current limitations, we need to shed some light on trends and constraints in current research. The goal of this study is to identify current trends and gaps based on analysis of selected papers, by the help of which we can facilitate further advance in the field. We searched the literature for plankton phenology and confined our search to studies where climate change has been proposed to alter plankton phenology and rates of changes were quantified. We did not restrict our search for empirical ontributions; experimental and theoretical studies were considered as well. In the following we discuss the spatio-temporal setting of selected studies, contributions of different taxonomic groups, emerging methodological constraints, measures of phenological trends; and finally give a list of recommendations on how to improve our understanding in the field. The majority of studies were confined to deep lakes with a skewed geographical distribution toward Central Europe, where scientists have long been engaged in limnology. Despite these findings, recent studies suggest that plankton in running waters may experience change in phenology with similar magnitude. Average rate of advancement in phenology of freshwater plankton exceeded those of the marine plankton and the global average. Increasing study duration was not coupled either with increasing contribution of discontinuous data or with increasing rates of phenological changes. Future studies may benefit from i) delivering longterm data across scientific and political boundaries; ii) extending study sites to broader geographical areas with a more explicit consideration of running waters; iii) applying plankton functional groups; iv) increasing the application of satellite data to quantify phytoplankton bloom phenology; v) extending analyses of time series beyond the spring period; vi) using various metrics to quantify variation in phenology; vii) combining empirical, experimental and theoretical approaches; and last but not least viii) paying more attention to emergence dynamics, nonresponding species and trophic mismatch.
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Hurricanes, earthquakes, floods, and other serious natural hazards have been attributed with causing changes in regional economic growth, income, employment, and wealth. Natural disasters are said to cause; (1) an acceleration of existing economic trends; (2) an expansion of employment and income, due to recovery operations (the so-called silver lining); and (3) an alteration in the structure of regional economic activity due to changes in "intra" and "inter" regional trading patterns, and technological change.^ Theoretical and stylized disaster simulations (Cochrane 1975; Haas, Cochrane, and Kates 1977; Petak et al. 1982; Ellson et al. 1983, 1984; Boisvert 1992; Brookshire and McKee 1992) point towards a wide scope of possible negative and long lasting impacts upon economic activity and structure. This work examines the consequences of Hurricane Andrew on Dade County's economy. Following the work of Ellson et al. (1984), Guimaraes et al. (1993), and West and Lenze (1993; 1994), a regional econometric forecasting model (DCEFM) using a framework of "with" and "without" the hurricane is constructed and utilized to assess Hurricane Andrew's impact on the structure and level of economic activity in Dade County, Florida.^ The results of the simulation exercises show that the direct economic impact associated with Hurricane Andrew on Dade County is of short duration, and of isolated sectoral impact, with impact generally limited to construction, TCP (transportation, communications, and public utilities), and agricultural sectors. Regional growth, and changes in income and employment reacted directly to, and within the range and direction set by national economic activity. The simulations also lead to the conclusion that areal extent, infrastructure, and sector specific damages or impacts, as opposed to monetary losses, are the primary determinants of a disaster's effects upon employment, income, growth, and economic structure. ^
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Desegregation of social and public spaces was the most visible result of the Civil Rights Movement. After 1960, the integration of schools in Mississippi became a source of conflict. The social change of Civil Rights attacked the social order of White Resistance that supported the state superstructure. The public schools were a place for the discovery of identity for Blacks. The integrated on of the schools caused many Whites to leave rather than be integrated with Blacks. Desegregation of schools was also a slow process because the local and state government could not enforce the decisions of the US Courts, leading Blacks to realize their place in American society could only be secured through individual action. ^ This work explains the role of schooling during the integration of the Holly Springs Separate School System. The process of forging a new identity by local Blacks is examined against the forces of social change and resistance. I addition, this work examines the perils for the Blacks as they faced the uncertainty of change in the crucial Civil Rights years between 1964 and 1974. ^ This work analyzes how the Black community dealt with the problems triggered by the desegregation of the school system in Holly Springs, of a constructed social condition, a psychological state of being, the realities of racism and segregation, and the change and resistance between the individual and the collective. It is based on six months of field work investigation. Although the schools were a crucial aspect of community life for Blacks and Whites, Blacks did form their identity in them. Other institutions, such churches were more crucial. Second, the aspect of politeness and belief in law made the experience in Holly Springs unique to that place, and thus, warrants further study to determine its place within the Civil Rights Movement. Finally, while the political and economic control of Holly Springs remained with Whites, desegregation led to the resegregation of the public schools: as Whites left to private schools. ^
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In the Florida Everglades, tree islands are conspicuous heterogeneous elements in a complex wetland landscape. I investigated the effects of increased freshwater flow in southern Everglades seasonally flooded tree islands, and characterized biogeochemical interactions among tree islands and the marsh landscape matrix, specifically examining hydrologic flows of nitrogen (N), and landscape N sequestration capacity. I utilized ecological trajectories of key ecosystem variables to differentiate effects of increased sheetflow and hydroperiod. I utilized stable isotope analyses and nutrient content of tree island ecosystem components to test the hypothesis that key processes in tree island nitrogen cycling would favor ecosystem N sequestration. I combined estimates of tree island ecosystem N standing stocks and fluxes, soil and litter N transformation rates, and hydrologic inputs of N to quantify the net sequestration of N by a seasonally flooded tree island. ^ Results show that increased freshwater flow to seasonally flooded tree islands promoted ecosystem oligotrophy, whereas reduced flows allowed some plant species to cycle P less efficiently. As oligotrophy is a defining parameter of Everglades wetlands, and likely promotes belowground production and peat development, reintroducing freshwater flow from an upstream canal had a favorable effect on ecosystem dynamics of tree islands in the study area. Important factors influencing the stable isotopic composition of nitrogen and carbon were: (1) a contribution to soil N by soil invertebrates, animal excrement, and microbes, (2) a possible NO3 source from an upstream canal and an "open" ecosystem N cycle, and (3) greater availability of phosphorus in tree islands relative to the marsh landscape, suggesting that tree island N cycling favors N sequestration. Hydrologic sources of N were dominated by surface water loads of NO3- and NH 4+, and an important soil N transformation promoting the net loss of surface water DIN was nitrate immobilization associated with soils and surficial leaf litter. The net inorganic N sequestration capacity of a seasonally flooded tree island was 50 g yr-1 m -2. Thus, tree islands likely have an important function in landscape sequestration of inorganic N, and may reduce significant anthropogenic N loads to downstream coastal systems. ^
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Establishing an association between the scent a perpetrator left at a crime scene to the odor of the suspect of that crime is the basis for the use of human scent identification evidence in a court of law. Law enforcement agencies gather evidence through the collection of scent from the objects that a perpetrator may have handled during the execution of the criminal act. The collected scent evidence is consequently presented to the canines for identification line-up procedures with the apprehended suspects. Presently, canine scent identification is admitted as expert witness testimony, however, the accurate behavior of the dogs and the scent collection methods used are often challenged by the court system. The primary focus of this research project entailed an evaluation of contact and non-contact scent collection techniques with an emphasis on the optimization of collection materials of different fiber chemistries to evaluate the chemical odor profiles obtained using varying environment conditions to provide a better scientific understanding of human scent as a discriminative tool in the identification of suspects. The collection of hand odor from female and male subjects through both contact and non-contact sampling approaches yielded new insights into the types of VOCs collected when different materials are utilized, which had never been instrumentally performed. Furthermore, the collected scent mass was shown to be obtained in the highest amounts for both gender hand odor samples on cotton sorbent materials. Compared to non-contact sampling, the contact sampling methods yielded a higher number of volatiles, an enhancement of up to 3 times, as well as a higher scent mass than non-contact methods by more than an order of magnitude. The evaluation of the STU-100 as a non-contact methodology highlighted strong instrumental drawbacks that need to be targeted for enhanced scientific validation of current field practices. These results demonstrated that an individual's human scent components vary considerably depending on the method used to collect scent from the same body region. This study demonstrated the importance of collection medium selection as well as the collection method employed in providing a reproducible human scent sample that can be used to differentiate individuals.
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Debate concerning bilingual education effectiveness may focus around the definition of academic language. Two aspects of such-vocabulary and grammar-were examined in 4th and 8th grade textbooks. Results showed substantial increases in the number of abstract words and complex sentences, suggesting more daunting language demands for older non-English-speaking students.
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This paper introduces a new construct that we term Math Mediated Language (MML) focusing on the notion that common or everyday terms with mathematical meanings are important building blocks for students’ mathematical reasoning. A survey given to 96 pre-service early childhood educators indicated clear patterns of perceptions of these terms.
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Climate change has been a security issue for mankind since Homo sapiens first emerged on the planet, driving him to find new and better food, water, shelter, and basic resources for survival and the advancement of civilization. Only recently, however, has the rate of climate change coupled with man’s knowledge of his own role in that change accelerated, perhaps profoundly, changing the security paradigm. If we take a ―decades‖ look at the security issue, we see competition for natural resources giving way to Cold War ideological containment and deterrence, itself giving way to non-state terrorism and extremism. While we continue to defend against these threats, we are faced with even greater security challenges that inextricably tie economic, food and human security together and where the flash points may not provide clearly discernable causes, as they will be intrinsically tied to climate change. Several scientific reports have revealed that the modest development gains that can be realized by some regions could be reversed by climate change. This means that climate change is not just a long-term environmental threat as was widely believed, but an economic and developmental disaster that is unfolding. As such, addressing climate change has become central to the development and poverty reduction by the World Bank and other financial institutions. In Latin America, poorer countries and communities, such as those found in Central America, will suffer the hardest because of weaker resilience and greater reliance on climatesensitive sectors such as agriculture. The US should attempt to deliver capability to assist these states to deal with the effects of climate change.
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Climate change is estimated to be responsible for 400,000 deaths per year, mostly because of hunger and communicable diseases affecting children in the Global South. Using the sociology of W.E.B. Du Bois, I attempt to demonstrate how and why climate change occurs along the color line. I conclude by arguing why it is important to think about climate change as a human rights issue.
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While there is considerable literature on neoliberalism in and of nature and the environment as well as in the interface between climate change and globalization, attempts at marrying the various conceptualizations of these have been limited. In this paper, I briefly review a portion of the literature on climate change and globalization (both broadly defined) locating the connections and disconnections on the topic. I then attempt to synthesize some of the ideas and problems expressed in many of these existing approaches to develop a Deleuzoguattarian approach to the intersections of climate change and globalization across spaces and scales. Finally, I argue that a non-linear historical materialism provides a way of addressing the limitations in existing frameworks.
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This paper describes the implementation of a novel mitigation approach and subsequent adaptive management, designed to reduce the transfer of fine sediment in Glaisdale Beck; a small upland catchment in the UK. Hydro-meteorological and suspended sediment datasets are collected over a two year period spanning pre- and post-diversion periods in order to assess the impact of the channel reconfiguration scheme on the fluvial suspended sediment dynamics. Analysis of the river response demonstrates that the fluvial sediment system has become more restrictive with reduced fine sediment transfer. This is characterised by reductions in flow-weighted mean suspended sediment concentrations from 77.93 mg/l prior to mitigation, to 74.36 mg/l following the diversion. A Mann-Whitney U test found statistically significant differences (p < 0.001) between the pre- and post-monitoring median SSCs. Whilst application of one-way analysis of covariance (ANCOVA) on the coefficients of sediment rating curves developed before and after the diversion found statistically significant differences (p < 0.001), with both Log a and b coefficients becoming smaller following the diversion. Non-parametric analysis indicates a reduction in residuals through time (p < 0.001), with the developed LOWESS model over-predicting sediment concentrations as the channel stabilises. However, the channel is continuing to adjust to the reconfigured morphology, with evidence of a headward propagating knickpoint which has migrated 120 m at an exponentially decreasing rate over the last 7 years since diversion. The study demonstrates that channel reconfiguration can be effective in mitigating fine sediment flux in upland streams but the full value of this may take many years to achieve whilst the fluvial system, slowly readjusts.
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Parent-mediated early intervention programs depend on the willingness and ability of parents to complete prescribed activities with their children. In other contexts, internal factors, such as stages of change, and external factors, such as barriers to treatment, have been shown to correlate with adherence to service. This researcher modified the Stages of Change Questionnaire as well as the Barriers to Treatment Participation Scale (BTPS) to use with this population. Despite initial interest, twenty-three parent participants were referred to the researcher over the course of three years, with only five parents taking part in the study. A population base ten times that of the current sample would be required recruit enough participants (fifty-one) to provide sufficient power. This feasibility study discusses the results of the five parent participants. Findings suggest that the modified Stages of Change Questionnaire may not be sensitive enough for use with the current sample, while the modified BTPS may yield useful information for service providers.
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Acknowledgements This work was funded by the projects HAR2013-43701-P (Spanish Economy and Competitiveness Ministry) and CGL2010-20672 (Spanish Ministry of Science and Innovation). This research was also partially developed with Xunta de Galicia funding (grants R2014/001 and GPC2014/009). N. Silva-Sánchez is currently supported by a FPU pre-doctoral grant (AP2010-3264) funded by the Spanish Government. We are grateful to Ana Moreno, Mariano Barriendos and Gerardo Benito who kindly provide us data included in Figure 5a. We also want to thank constructive comments from two anonymous reviewers.
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Acknowledgements This work was funded by the projects HAR2013-43701-P (Spanish Economy and Competitiveness Ministry) and CGL2010-20672 (Spanish Ministry of Science and Innovation). This research was also partially developed with Xunta de Galicia funding (grants R2014/001 and GPC2014/009). N. Silva-Sánchez is currently supported by a FPU pre-doctoral grant (AP2010-3264) funded by the Spanish Government. We are grateful to Ana Moreno, Mariano Barriendos and Gerardo Benito who kindly provide us data included in Figure 5a. We also want to thank constructive comments from two anonymous reviewers.