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Avaliação da toxicidade, citotoxicidade e de características fenológicas e físico-químicas da planta Pereskia aculeata / Toxicity, cytotoxicity, phenological, and physicochemical evaluations of Pereskia aculeata plantSilva, Débora Oliveira da 17 February 2017 (has links)
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Previous issue date: 2017-02-17 / Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul - FAPERGS / A planta Pereskia aculeata é uma hortaliça não convencional que possui
grande potencial alimentar devido aos seus elevados teores de minerais,
aminoácidos, vitaminas, fibras e antioxidantes. Entretanto, informações sobre
características fenológicas, químicas e toxicológicas da planta, especialmente
quando cultivada em região subtropical de clima temperado, são limitadas ou
inexistentes. Assim, a planta P. aculeata foi cultivada sob clima temperado, em
Pelotas, RS, Brasil, e avaliada quanto aos seguintes aspectos: (a) toxicidade
aguda, (b) citotoxicidade, (c) características fenológicas e (d) características
físico-químicas. A análise da toxicidade aguda foi realizada por meio de ensaio
biológico, que utilizou 24 ratas, adultas, da linhagem Wistar. Os animais foram
distribuídos em quatro grupos, de acordo com as doses administradas de
extrato etanólico da planta P. aculeata: 0 mg/kg, 1250 mg/kg, 2500 mg/kg e
5000 mg/kg de massa corporal. O experimento teve duração de 15 dias e após
a eutanásia foram realizadas avaliações histopatológicas em 8 órgãos. A
citotoxicidade da P. aculeata foi avaliada utilizando-se alface (L. sativa) como
modelo experimental. Sementes de alface foram tratadas com diferentes doses
de extrato de P. aculeata (0,13 mg/ml; 1,30 mg/ml; 3,25 mg/ml; 6,50 mg/ml;
13,00 mg/ml) e avaliadas quanto ao índice de germinação, crescimento de raiz,
crescimento de parte aérea, e índice mitótico. Durante 12 meses a planta foi
avaliada periodicamente quanto a características físico-química (teor de
umidade, área foliar, proteína, cor, fenóis totais e atividade antioxidante) e
fenológicas (mudança foliar, floração e frutificação). Observou-se que P.
aculeata não possui efeito tóxico em ratos, na dose de até 5000 mg/kg de
massa corporal. A planta apresentou reduzido efeito citotóxico sobre alface,
consistindo em alteração no crescimento de raízes e partes aéreas, porém sem
comprometimento da germinação e sem efeito genotóxico na semente. No
estudo fenológico observou-se boa adaptação da planta ao clima temperado,
caracterizado pelo pleno crescimento e desenvolvimento. Entretanto, destacase
um período de quiescência durante o inverno, no qual a planta não produziu
folhas. Concluiu-se que o cultivo de P. aculeata é viável em clima temperado e
que seu consumo alimentar é seguro. / The Pereskia aculeata plant has valuable nutritional properties and could be a
supplementary food source, because it contains high amounts of minerals,
amino acids, vitamins, fibers and antioxidants. However, we have limited
information about toxicity, cytotoxicity, phenological and physicochemical
characteristics of this plant, particularly when cultivated in subtropical areas with
temperate climate. Thus, we analyzed Pereskia aculeata plants cultivated in
Pelotas, RS, Brazil, under temperate climate, for: (a) acute toxicity, (b)
cytotoxicity, (c) phenological characteristics and (d) physicochemical properties.
The acute toxicity experiment was performed with 24 female Wistar rats. The
animals were divided into four groups, according to the single dose of ethanolic
plant extract they received: 0 mg/kg, 1250 mg/kg, 2500 mg/kg e 5000 mg/kg of
body weight. After a 15 days period of observation the euthanasia was
performed and 8 different animal tissues were sampled for histopathological
analysis. The cytotoxicity was evaluated using lettuce (L. sativa) as an
experimental model. The lettuce seeds were treated with different doses of P.
aculeata extract (0.13 mg/ml; 1.30 mg/ml; 3.25 mg/ml; 6.50 mg/ml; 13.00
mg/ml) and analyzed for germination and mitotic indexes, and also for roots and
shoots length. During 12 months cultivation period the plant was analyzed for
physicochemical properties (humidity, color, leaf area, protein content,
antioxidant activity, total phenolic content) and phenological aspects (leaf
changes, flowering and fructification). Our results for acute toxicity of Pereskia
aculeata show that it has non-toxic effect to rats at concentrations of
5000 mg/kg of body weight. We also found this plant to have minimal
deleterious cytotoxicity effects on lettuce, consisting of abnormal growth of roots
and shoots, but without affecting germination or causing genotoxic effect on
lettuce seeds. Furthermore, Pereskia aculeata showed a good adaptation under
temperate climate, with normal growth and development. Though, a quiescent
state happened in the winter and the plant did not produce leaves. We conclude
that cultivation of Pereskia aculeata under temperate climate is feasible and
also, the leaves of these plants are safe for consumption as food.
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Sustainability assessment of energy systemsGaudreau, Kyrke 08 May 2013 (has links)
This research project set out to develop and apply a framework for assessing how energy systems may be structured to help society progress towards sustainability. The general intent was to outline a way to decide upon the things that matter in order to make better decisions that will lead to positive near- and long-term outcomes. There are various ways of reaching the goal described above, and the path chosen in this dissertation centred on Gibson’s (2006) sustainability assessment framework, an approach to integrated sustainability-based decision-making. In order to contribute to extending and specifying Gibson’s approach to sustainability assessment for energy undertakings, this project developed a theoretical framework grounded in various forms of complexity and energy.
The journey described in the dissertation begins with an exploration of the complexity of science, the subject of Chapter 2. We live in a world characterized by inherent uncertainty, multiple worldviews, conflicting values, power dynamics and a whole host of other challenges to science and decision-making. Many of the environmental and human challenges we currently face have arisen in part because we do not sufficiently respect the limits to knowledge and the personal biases we all bring to the table. Chapter 2 develops a framework for knowledge generation and decision-making situated within its social context, and operationalizes this framework through the process of criteria specification. Drawing from multiple sources of data – particularly documentary analysis, semi-structured interviews and observation – the criteria specification cycle provided the means of and determining and deciding upon the things that matter in a given case and context.
The complexity of science is only half the story emerging from the complex systems literature. From a different perspective, it is evident that we live in a world of complex dynamics and interconnections, and it is important to ensure that whatever energy paths we set out on recognize these dynamics. Fortunately, there is a wide range of literature relating to the characteristics of complex systems in general, as well as their energy and material flows in societies. These literatures are explored in Chapter 3 to develop an understanding of and guidelines for managing complex systems to the extent possible and appropriate.
Building on the theory developed in Chapters 2 and 3, the discussion in Chapter 4 began to develop an understanding of energy systems and energy decision-making and was structured around three general questions: (1) what is the energy problem? (2) what are the characteristics of an appropriate and constructive relationship with energy? and (3) how can the necessary and desired sociotechnical systems changes be achieved. These questions were largely addressed through an exploration of the soft energy path and transition management and led to two sets of guidelines designed to address energy systems structure and change.
The theoretical framework developed over Chapters 2-4 was consolidated into a proposed set of sustainability criteria for energy undertakings. The sustainability criteria set represents the principal theoretical contribution of the dissertation to the academy and the broader assessment community, and outlines a suite of generally desirable system attributes and actions for achieving progress towards sustainability, as opposed to an acceptability threshold. The proposed sustainability criteria are primarily intended for application regarding energy undertakings at a wide variety of scales, but are much more broadly relevant.
In a manner that is more iterative than can be described in this abstract, the sustainability assessment framework described in this dissertation was applied in, and enriched through, four distinct case studies that assessed
(1) the 2006 Ontario Integrated Power Systems Plan proposed by the Ontario Power Authority. The Integrated Power Systems Plan was originally framed as a coal versus nuclear problem, as opposed to a critical appraisal of power systems planning; and in doing so it underplayed potential for conservation, demand management, increased renewable energy, and social change;
(2) a small-scale biodiesel operation in Barbados. The plant owner collected used cooking oil from restaurants, roadside stands, and individual homes, and converted it into biodiesel using a first-generation processing technology known as transesterification.
(3) a sugarcane-ethanol plant in the Tietê-Jacaré Watershed of São Paulo, Brazil. The sugarcane ethanol mill harvests approximately 21,000 hectares of sugarcane crops from seven municipalities and produces hydrated ethanol for domestic markets, and sugar for domestic and international markets; and
(4) the agricultural and energy systems in Senegal. Senegal suffers from significant deforestation and soil fertility decline coupled with demographic change. The many interconnections between the energy and agricultural systems require an integrated assessment of both.
Each individual case study stands alone in providing novel insights emerging from application of the framework in the particular case and context. At the more general level, five important insights emerged from the case studies, including: (1) the benefits of, and need for, maintaining a flexible unit of analysis so as to improve problem structuring; (2) the importance of grounding an assessment within its context; (3) the benefits of seeking integration and positive indirect effects; (4), the need to plan for and develop energy bridges towards feasible and desirable energy futures; and (5), the need for caution in the face of thresholds and uncertainty.
The individual and general insights from the case studies were incorporated into the most recent version of the sustainability assessment framework described in this dissertation. The framework is suitable for application, with specification for particular case and context, to all types of energy systems at all scales.
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Late Holocene Paleoenvironmental Reconstruction in BarbadosOuellette, Gilman Reno 01 August 2013 (has links)
Barbados is the easternmost island in the Caribbean region, and is uniquely situated between the Atlantic Ocean and Caribbean Sea. Being an isolated island with a karstified aquifer providing the majority of the nation’s water resources, Barbados has found itself in water scarce situations in recent years. In order to better understand natural shifts in groundwater recharge (which is determined by shifts in precipitation), longer records of precipitation are needed than are available from modern measurements. This study presents a paleoclimate reconstruction for the late Holocene on Barbados using stable and radiogenic isotope ratios in speleothem lamina as proxies. In addition, it introduces the use of novel mineralogical analyses using Raman spectroscopy and large chamber-scanning electron microscopy to supplement the oxygen isotope record. For the past 1,500 years, the speleothem record indicates average δ18O values near -4.1 0/00, maximum δ18O values around -3.2 0/00 that coincide with the Little Ice Age climate event, while minimum δ18O values around -5.3 0/00 occur during the Medieval Climate Anomaly. Raman spectral analysis shows a recent period of increased Mg substitution, which potentially represents anthropogenic changes to the island’s epikarst aquifer caused by European settlement and sugar cane cultivation on Barbados. Electron imaging revealed chemically distinct layers of detritus within the stalagmite sample, facilitating precise sampling for U-series dating while also providing some information on the nature of weathering on the island. Additionally, time series analysis of the isotope record indicates multidecadal and multicentennial periodicities that conform well to that of the Atlantic Multidecadal Oscillation exerting influence on rainfall variability at the decadal scale, and the Intertropical Convergance Zone modulating rainfall at the multicentennial scale. Collectively, these data provide a climate reconstruction for the island of Barbados that is useful for better understanding change in cyclic precipitation patterns, as well as non-destructive methods for speleothem analysis that complement the isotopic study, while allowing sample preservation.
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At the Sea’s Edge: Elders and Children in the Littorals of Barbados and the BahamasStoffle, Brent W., Stoffle, Richard W. 27 January 2007 (has links)
Littorals in the in the Exuma Cays, Bahamas and the Bath Plantation, Barbados are comparative in many ways. These edges of the sea have provided critical services to local people during the time of slavery and since. More than food and medicine, the littoral is the nightly sea bath, where children are instructed, and the last ecosystem effectively used by the elderly. Independence and self- respect derive from use and protection of these littoral by individuals and communities. Local patterns of conservation and use are argued to be essential in the ecological structure and functions of the littoral. Development projects and marine protected areas alike are seen as potentially breaking local ties with the littoral causing trophic skew and damaging local society. If development occurs, mitigation solutions potentially derive from legally recognizing local people as partners in the co-management of their traditional littoral. Included with this article is a presentation prepared by Drs. Brent and Richard Stoffle.
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Educational journeys of Barbadian womenEdghill, Gina. January 2010 (has links)
This study is an exploration of the educational experiences of women from the Caribbean island of Barbados who traveled to the USA to pursue higher education. An autoethnography research methodology was used in order to capture each woman’s educational experiences. Autoethnography also supported the inclusion of the researcher’s voice and interpretations as a Barbadian woman fitting the criteria for participation. These educational journeys represented the field and cultural world under study. Through analysis, themes emerged from each woman's description of Influential Others; Protagonist Self; and Educational Settings within her storied journey. Storied experiences in relation to race, ethnicity, and being women and the role American Higher Education had in each woman's life were also analyzed. The emergent themes supported
the existence of a web of interacting narratives spun first in Barbados and extending to
American Higher Education. Through the educational settings each woman interacted
with, this web of narratives linked her educational journey to the narratives of the people who went before her; beside her; and after her. This web of narratives also supports each
woman’s storied understanding of self, others, and settings within that journey. / Access to thesis permanently restricted to Ball State community only / Department of Educational Studies
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Sustainability assessment of energy systemsGaudreau, Kyrke 08 May 2013 (has links)
This research project set out to develop and apply a framework for assessing how energy systems may be structured to help society progress towards sustainability. The general intent was to outline a way to decide upon the things that matter in order to make better decisions that will lead to positive near- and long-term outcomes. There are various ways of reaching the goal described above, and the path chosen in this dissertation centred on Gibson’s (2006) sustainability assessment framework, an approach to integrated sustainability-based decision-making. In order to contribute to extending and specifying Gibson’s approach to sustainability assessment for energy undertakings, this project developed a theoretical framework grounded in various forms of complexity and energy.
The journey described in the dissertation begins with an exploration of the complexity of science, the subject of Chapter 2. We live in a world characterized by inherent uncertainty, multiple worldviews, conflicting values, power dynamics and a whole host of other challenges to science and decision-making. Many of the environmental and human challenges we currently face have arisen in part because we do not sufficiently respect the limits to knowledge and the personal biases we all bring to the table. Chapter 2 develops a framework for knowledge generation and decision-making situated within its social context, and operationalizes this framework through the process of criteria specification. Drawing from multiple sources of data – particularly documentary analysis, semi-structured interviews and observation – the criteria specification cycle provided the means of and determining and deciding upon the things that matter in a given case and context.
The complexity of science is only half the story emerging from the complex systems literature. From a different perspective, it is evident that we live in a world of complex dynamics and interconnections, and it is important to ensure that whatever energy paths we set out on recognize these dynamics. Fortunately, there is a wide range of literature relating to the characteristics of complex systems in general, as well as their energy and material flows in societies. These literatures are explored in Chapter 3 to develop an understanding of and guidelines for managing complex systems to the extent possible and appropriate.
Building on the theory developed in Chapters 2 and 3, the discussion in Chapter 4 began to develop an understanding of energy systems and energy decision-making and was structured around three general questions: (1) what is the energy problem? (2) what are the characteristics of an appropriate and constructive relationship with energy? and (3) how can the necessary and desired sociotechnical systems changes be achieved. These questions were largely addressed through an exploration of the soft energy path and transition management and led to two sets of guidelines designed to address energy systems structure and change.
The theoretical framework developed over Chapters 2-4 was consolidated into a proposed set of sustainability criteria for energy undertakings. The sustainability criteria set represents the principal theoretical contribution of the dissertation to the academy and the broader assessment community, and outlines a suite of generally desirable system attributes and actions for achieving progress towards sustainability, as opposed to an acceptability threshold. The proposed sustainability criteria are primarily intended for application regarding energy undertakings at a wide variety of scales, but are much more broadly relevant.
In a manner that is more iterative than can be described in this abstract, the sustainability assessment framework described in this dissertation was applied in, and enriched through, four distinct case studies that assessed
(1) the 2006 Ontario Integrated Power Systems Plan proposed by the Ontario Power Authority. The Integrated Power Systems Plan was originally framed as a coal versus nuclear problem, as opposed to a critical appraisal of power systems planning; and in doing so it underplayed potential for conservation, demand management, increased renewable energy, and social change;
(2) a small-scale biodiesel operation in Barbados. The plant owner collected used cooking oil from restaurants, roadside stands, and individual homes, and converted it into biodiesel using a first-generation processing technology known as transesterification.
(3) a sugarcane-ethanol plant in the Tietê-Jacaré Watershed of São Paulo, Brazil. The sugarcane ethanol mill harvests approximately 21,000 hectares of sugarcane crops from seven municipalities and produces hydrated ethanol for domestic markets, and sugar for domestic and international markets; and
(4) the agricultural and energy systems in Senegal. Senegal suffers from significant deforestation and soil fertility decline coupled with demographic change. The many interconnections between the energy and agricultural systems require an integrated assessment of both.
Each individual case study stands alone in providing novel insights emerging from application of the framework in the particular case and context. At the more general level, five important insights emerged from the case studies, including: (1) the benefits of, and need for, maintaining a flexible unit of analysis so as to improve problem structuring; (2) the importance of grounding an assessment within its context; (3) the benefits of seeking integration and positive indirect effects; (4), the need to plan for and develop energy bridges towards feasible and desirable energy futures; and (5), the need for caution in the face of thresholds and uncertainty.
The individual and general insights from the case studies were incorporated into the most recent version of the sustainability assessment framework described in this dissertation. The framework is suitable for application, with specification for particular case and context, to all types of energy systems at all scales.
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The Institutional Discourse of Development: The postcolonial condition and the case of the Caribbean Community (CARICOM)RIGELO, Chloé A. January 2019 (has links)
Using a discourse analysis, the thesis will examine the impact of the postcolonial condition and the desire for integration in the institutional framing of human development reports, policies and programs. Three levels will be used to contextualize the Caribbean expression of human development. First, the international level will be represented by the UNDP, central organ of the international development engine to provide the context of the international discourse. Then, regional and national levels with a case study of Barbados and Haiti will be investigated and evaluate to what extent does the postcolonial condition and identity enable the regional integration into the international development discourse. The paper seeks to verify empirically the Postcolonial criticism of development and produce IR Postcolonial empirical research on discourses to voice the Caribbean experiences. I argue that the region does not produce a counter-discourse to development and reject the claim that the postcolonial condition/subjectivity is an obstacle the use of the international development framework in the postcolonial Caribbean. To support my position, the notion of identity will be assessed highlighting the references to a regional identity put forward the unity of the region. The thesis will conclude that the attempt to foster a regional Caribbean identity is weaken by the ambivalence of the postcolonial subjectivity and the desire for integration.
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On the Path to Slavery: Indentured Servitude in Barbados and Virginia during the Seventeenth CenturyGrady, Timothy Paul 28 April 2000 (has links)
This is an investigation and analysis of the institution of indentured servitude in the English colonies of Virginia and Barbados in the first half of the seventeenth century. It argues that the system of indentured servitude contributed to the development of property rights in individuals and thereby provided early examples of treating people as property that would ultimately lead to the rise of chattel slavery in both colonies. It investigates servitude in law, politics, and practice providing examples of the treatment, trade, and resistance of servants throughout this period. Included are chapters examining the trade in servants and a statistical breakdown of the servant population, a comparison of the practice of servitude in both colonies, and a description of the factors that led to the eventual transition to black slavery. / Master of Arts
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Large Eddy Simulation Studies of Island Effects in the Caribbean Trade Wind RegionJähn, Michael 01 March 2016 (has links)
In dieser Dissertation wird das kompressible, nicht-hydrostatische und dreidimensionale Modell
All Scale Atmospheric Model (ASAM) für Grobstruktur- bzw.
Large-Eddy-Simulationen (LES) angewendet, um lokale
Inseleffekte in der karibischen Passatwindzone zu untersuchen.
Da das Modell bis dato noch keine Anwendung im Bereich von LES feuchter atmosphärischer
Grenzschichten und heterogener Oberflächen fand, wurden einige Bestandteile zum Modellcode
hinzugefügt oder überarbeitet. Ein Hauptaugenmerk liegt dabei auf das Einbeziehen orographischer
Strukturen mittels angeschnittener Zellen (engl. cut cells). Sowohl die räumliche und zeitliche
Diskretisierung der Modellgleichungen als auch die nötigen physikalischen Parameterisierungen werden
in einer umfassenden Modellbeschreibung zusammengefasst. Die Robustheit und Stabilität der Modellformulierung
wird durch eine Reihe von Simulationen idealisierter Testfälle bestätigt.
Large-Eddy-Simulationen werden für das Gebiet der Karibikinsel Barbados
zur Untersuchung von Inseleffekten bezüglich Grenzschichtmodifikation, Wolkenbildung
und vertikaler Durchmischung von Aerosolen durchgeführt. Durch das Vorhandensein
einer topographisch strukturierten Inseloberfläche in der Mitte des Modellgebietes
muss das Modellsetup offene seitliche Randbedingungen beinhalten. Damit das einströmende
Windfeld konsistent mit der Dynamik einer turbulenten, marinen Grenzschicht ist,
wird eine neue Methode implementiert und angewendet, welche auf Störungen des potentiellen Temperaturfeldes mittels finiter Amplituden basiert.
Beobachtungen aus der SALTRACE-Messkampagne werden benutzt, um die Modellläufe anzutreiben.
Die Ergebnisse einiger Sensitivitätstests zeigen Probleme der Modellierung im Bereich der \"Terra incognita\" auf. Dabei handelt es sich um die Modellierung auf räumlichen Skalen, welche
zwischen denen von LES und wolkenauflösenden Modellen liegen. Außerdem werden Auswirkungen von
entweder turbulent oder laminar anströmenden Windfeldern auf die Simulationsergebnisse untersucht.
Besonders die Wolkeneigenschaften im Lee von Barbados werden in diesen Simulationen merklich
beeinflusst. Ergebnisse einer weiteren Simulation mit einer sehr starken Passatinversion bringt
deren Einfluss auf die Dicke und Höhe der simulierten Wolkenschichten zum Vorschein. Die Veränderung von
Saharastaubschichten, welche Barbados über weiträumigen Transport über den Atlantik erreichen,
wird analysiert. Die Auswirkungen beinhalten sowohl eine Ausdünnung und ein Absinken dieser Schichten
als auch turbulenter Transport in Richtung Erdoberfläche.
Die genaue Position der beeinflussten Schichten und die Stärke des turbulenten Mischens
werden hauptsächlich von der atmosphärischen Schichtung, der Inversionsstärke und Windscherung
gesteuert. Vergleiche zwischen den LES-Modellergebnissen und Daten aus Doppler-Windlidarmessungen
zeigen gute Übereinstimmungen in der Formierung der konvektiven Strukturen tagsüber und
des Vertikalwindfeldes. / In this thesis, the fully compressible, three-dimensional,
nonhydrostatic atmospheric model called All Scale Atmospheric Model
(ASAM) is utilized for large eddy simulations (LES)
to investigate local island effects at the Caribbean.
Since the model has not been applied to LES for moist boundary layers
and heterogeneous surfaces so far, several parts are added to the model code
or reworked. A special focus lies on the inclusion of orographical structures
via the cut cell method. Spatial and temporal discretization as well as
necessary physical parameterizations are summarized in a thorough model description.
The robustness of the model formulation is confirmed by a set of idealized
test case simulations.
Large eddy simulations are performed for the area of the Caribbean island Barbados to investigate
island effects on boundary layer modification, cloud generation and vertical mixing of aerosols.
Due to the presence of a topographically structured island surface in the domain center,
the model setup has to be designed with open lateral boundaries.
In order to generate inflow turbulence consistent with the upstream marine boundary layer forcing,
the newly developed cell perturbation method based on finite amplitude perturbations is applied.
Observations from the SALTRACE field campaign are used to initialize the model runs.
Several numerical sensitivity tests are carried out
to demonstrate the problems related to \"gray zone modeling\" beyond LES scales
or when the turbulent marine boundary layer flow
is replaced by laminar winds. Especially cloud properties west of Barbados (downwind)
are markedly affected in these simulations.
Results of an additional simulation with a strong trade-wind inversion
reveal its effect on cloud layer depth and height.
The modification of Saharan dust layers reaching Barbados via
long-range transport over the North Atlantic is analyzed.
Effects of layer thinning, subsidence and turbulent downward transport
near the layer bottom become apparent.
The position of these layers and strength of downward mixing is found
to be mainly controlled atmospheric stability, inversion strength and wind shear.
Comparisons of LES model output with wind lidar data show similarities in the
formation of the daytime convective plume and the vertical wind structure.
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The influence of individual, team and contextual factors on external auditors' whistle-blowing intentions in Barbados : towards the development of a conceptual model of external auditors' whistle-blowing intentionsAlleyne, Philmore Alvin January 2010 (has links)
Following the collapse of Arthur Andersen in the Enron debacle, whistle-blowing within audit firms has taken on greater importance. Given the profession's requirements to be confidential, independent and to act in the public's interest, there is a need for a model that addresses auditors' whistle-blowing intentions. This thesis presents a conceptual model on whistle-blowing intentions among external auditors, where individual-led antecedents influence whistle-blowing intentions, but are moderated by isomorphic and issue-specific factors. Survey questionnaires were administered to 226 external auditors, and 18 individual interviews as well as 2 focus groups were conducted in Barbados. Results indicated that individual antecedents (attitudes, perceived behavioural control, independence commitment, personal responsibility for reporting, and personal cost of reporting) were significantly related to internal whistle-blowing, but only perceived behavioural control was significantly related to external whistle-blowing. Partial support was found for the moderating effects of perceived organizational support, moral intensity, team norms and group cohesion on the relationships between the majority of the independent variables (attitudes, perceived behavioural control, independence commitment, personal responsibility for reporting and personal cost of reporting) and internal whistle-blowing. However, partial support was found for the moderating effects of perceived organizational support, moral intensity, team norms iii and group cohesion on the relationships between fewer independent variables and external whistle-blowing. Overall, respondents preferred anonymous internal channels of reporting, and showed a general reluctance to report externally. The presence of an open-door policy, ethics partners, hotline, on-going training and clearly defined policies could encourage whistle-blowing. Further implications for research and practice are discussed.
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