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Stability of Whole Wheat Flour, Rolled Oats, and Brown Rice During Long-Term Storage and PreparationScott, Victoria Elizabeth 01 December 2015 (has links)
Whole grains are an increasingly popular health food in America. However, shelf life of whole grains is compromised due to the presence of lipoxygenases in the bran and germ, which lead to rancidity and generation of oxidative byproducts. These byproducts reduce sensory quality and may have a degradative effect on vitamins in whole grain products. The purpose of this study was to determine the degree of lipid and vitamin degradation during long-term storage of three whole grains: whole wheat flour, brown rice, and rolled oats. We also examined vitamin loss after cooking to determine if oxidative byproducts had an effect on vitamins during typical household cooking. Whole wheat flour, brown rice, and rolled oats were stored for 12 months and periodically analyzed for conjugated dienes, free fatty acids, tocopherols, thiamin, and riboflavin. Whole wheat bread, steamed brown rice, and oat porridge were made from samples stored for 0 months and 12 months and were analyzed for thiamin and riboflavin. Conjugated dienes increased significantly only in rolled oats, while tocopherols decreased significantly in whole wheat flour and rolled oats and insignificantly in brown rice. Free fatty acids increased significantly in whole wheat flour and brown rice. Thiamin and riboflavin were stable in raw stored grains and cooked products made from stored grains with the exception of brown rice, in which we observed a significant decrease in thiamin after 12-month storage and cooking. These results suggest whole wheat flour, brown rice, and rolled oats experience significant lipid and tocopherol degradation, but it does not appear to affect thiamin and riboflavin in raw stored products. Cooking appears to cause degradation of thiamin after storage of brown rice, but thiamin and riboflavin were otherwise stable in these whole grains.
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Charles Brockden Brown's place within the gothic and the influence of early America's social issues on Brown's writingRegis, Shirley Ann 01 January 2007 (has links)
The purpose of this thesis is to show that Charles Brockden Brown was influenced by the American Revolution and the incidents that come after it. It is suggested that Brown created a gothic fiction that was intended to be a critique on the American Revolution by using murder narrratives present during the time to create his characters. Gothic fiction consists of many elements such as setting arechetypal characters, terror, emotion, psychological turmoil and language use.
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Modifications métaboliques induites par la prise en charge thérapeutique des patientes atteintes d'un cancer du sein / Metabolic changes induced during therapeutic management in breast cancer patientsGinzac Couvé, Angeline 03 April 2019 (has links)
Il existe une relation étroite entre le cancer du sein et le poids. Si l’excès de poids est un facteur de risque de survenue du cancer du sein, l’obésité au diagnostic et les variations de poids (± 5 % du poids initial) au cours des traitements sont associées à un mauvais pronostic. La perte et le gain de poids résultent d’un déséquilibre de la balance énergétique (apports et dépenses). Les caractéristiques et les causes de ces variations ne sont pas encore totalement décrites. La prise de masse grasse semble être reconnue comme un facteur de mauvais pronostic d’où l’importance de bien comprendre l’évolution de la composition corporelle au cours des traitements du cancer du sein.Dans ce contexte, les objectifs de cette thèse ont été de caractériser la variation de poids et de composition corporelle tout au long des traitements du cancer du sein et d’étudier les facteurs impliqués dans le déséquilibre de la balance énergétique dont l’activité physique et certaines composantes de la dépense énergétique de repos.Les travaux menés dans le cadre de cette thèse se sont articulés autour de trois essais cliniques. En premier lieu, l’essai MétaCa2 qui vise à décrire l’évolution à long terme du poids et de la composition corporelle de patientes ménopausées atteintes d’un cancer du sein non métastatique (en moyenne 3 ans post-chimiothérapie). Les résultats cette étude ont montré qu’une perte de poids pendant la chimiothérapie est corrélée à une prise de poids dans la suite des traitements adjuvants. Cette étude a également permis de mettre évidence une prise de poids et de masse grasse au cours de l’hormonothérapie dans la population globale et plus particulièrement chez les patientes en excès de masse grasse au diagnostic. L’augmentation du temps assis entre la fin de la chimiothérapie et le début de l’hormonothérapie a été identifiée comme un facteur lié à la prise de masse grasse à long terme.Nous avons ensuite exploré une hypothèse avancée par notre équipe qui suggère que la chimiothérapie pourrait avoir un impact sur le tissu adipeux brun. Celui-ci est impliqué dans la thermogénèse adaptative, donc dans les dépenses énergétiques, et pourrait ainsi contribuer à la prise de poids. Pour cela, nous avons réalisé une étude ancillaire au protocole AVATAXHER sur 109 patientes atteintes d’un cancer du sein HER2+ et traitées par chimiothérapie néoadjuvante et thérapie ciblée anti-HER2. Les résultats ont mis en évidence une diminution significative de l’activité métabolique du tissu adipeux brun après une cure de chimiothérapie dans la population générale et plus particulièrement dans le sous-groupe de patientes qui prennent du poids au cours de la chimiothérapie.L’activité physique constitue une possible stratégie de prévention individuelle sur les variations de poids et de composition corporelle. Dans la sous-population de patientes HER2+, elle pourrait également permettre de limiter la cardiotoxicité des traitements standards utilisés. Nous avons mis en place un essai interventionnel prospectif afin d’étudier la faisabilité d’une intervention d’activité physique à domicile pour des patientes en cours de chimiothérapie néoadjuvante + thérapie ciblée pour un cancer du sein HER2 positif. L’intervention consiste à atteindre ou maintenir un niveau d’activité physique correspondant aux recommandations internationales soit 150 minutes par semaine à une intensité modérée grâce à un programme personnalisé combinant activité physique de type aérobie et renforcement musculaire. Ces résultats originaux ont ainsi conduit à apporter de nouvelles connaissances quant aux variations de poids et de composition corporelle au cours des traitements du cancer du sein à un stade précoce et sur les causes possibles du déséquilibre énergétique. / There is a close relationship between breast cancer and weight. If weight excess is a risk factor for the onset of breast cancer, obesity at diagnosis and weight variations (± 5 % of initial weight) during treatement are associated with poor prognosis. Weight loss and weight gain result in an energy imbalance (energy intake and energy expenditure). The caracteristics and causes of these variations are not well described. Fat mass gain seems to be recognized as a factor of poor prognosis hence the importance to understand body composition evolution during breast cancer treatment.In this context, the aims of this thesis were to characterized weight and body compostion variation throughout treatment and to study the factors involved in the energy imbalance of which physical activity and certain components of resting energy expenditure.This thesis works have been centered around three clinical trials. Firstly, MétaCa2 trial that attempted to describe the long term evolution of weight and body composition among no-metastatic postmenopausal breast cancer patients (on average 3 years post-chemotherapy). The results of this study have shown that weight loss during chemotherapy is associated with a later weight gain during adjuvant period of treatment. This study has also demonstrated a weight and fat mass gain during endocrine therapy in the overall population and more especially for the patients with an initial fat mass excess. The increase in time spent sitting between the end of chemotherapy and the initiation of endocrine therapy has been identified has a factor associated with long term fat mass gain.Then, we have explored a hypothesis, supported by our team, suggesting that chemotherapy could have an impact on brown adipose tissue. This one is implied in the adaptative thermogenesis and so in energy expenditure and could contribute to weight gain. For this end, we realised an ancillary study to AVATAXHER trial among 109 HER2+ breast cancer patients treated with neoadjuvant chemotherapy and HER2 targeted therapy. The results have highlighted a significant decrease of BAT metabolic activity after one course of chemotherapy in the overall population and specifically in the subgroup of patients who gained weight during chemotherapy. Physical activity constitutes a possible strategy for individual prevention against weight and body composition variation. In the HER2+ subpopulation, it could also limit the cardiotoxicity of standard treatements. We have set up a prospective interventional trial in order to study the feasibility of a home-based physical activity intervention among HER2+ breast cancer patients currently treated with neoadjuvant chemotherapy + targeted therapy. The objective of the intervention is to achieve or maintain a physical activity level corresponding to the international recommendations, i.e. at least 150 minutes of moderate-intensity physical activity per week thanks to a personalised program combining aerobic physical activity and muscular strengthening.These original results have contributed to provide new knowledge about weight and body composition variation during early breast cancer treatments and also about some potential causes imply in energy imbalance.
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Habitat fragmentation and the southern brown bandicoot Isoodon obesulus at multiple spatial scalesPaull, David James, Physical, Environmental & Mathematical Sciences, Australian Defence Force Academy, UNSW January 2003 (has links)
This thesis investigates the process of habitat fragmentation and the spatial and temporal scales at which it occurs. Fragmentation has become an important topic in biogeography and conservation biology because of the impacts it has upon species??? distributions and biodiversity. Various definitions of fragmentation are available but in this research it is considered to be the disruption of continuity, either natural or human-induced in its origins and operative at multiple spatial scales. Using the distribution of the southern brown bandicoot Isoodon obesulus as a case study, three spatial scales of fragmentation were analysed. At the continental scale, the Australian distribution of the subspecies I. o. obesulus was examined in relation to climate, geology and vegetation cover at the time of European settlement of Australia and two centuries later. Using archived wildlife records and Geographic Information Systems (GIS) analyses, habitat suitability models were created to assess natural and human-induced fragmentation of the distribution of I. obesulus in 1788 and 1988. At the regional scale, a study was made of the distribution of I. obesulus in the south-east of the State of South Australia. Again, natural and human-induced patterns of habitat fragmentation were modelled using GIS with climate, soil and vegetation data for the time of European settlement and at present. At the local scale, the distribution of I. obesulus was the subject of a detailed field survey of 372 sites within 29 remnant patches of native vegetation in south-eastern South Australia in order to understand the variables that cause habitat fragmentation. Geographic information systems were used again but in a different way to carefully stratify the field survey by overlaying maps of topography, vegetation and past fires. The large dataset collected from the surveys was described using six generalized linear models which identified the significant variables that fragment the distribution of I. obesulus at a local scale. From the results of the field surveys, a subset of four remnants was chosen for further GIS spatial modelling of the probability of I. obesulus occurring within remnants in response to fire via a controlled burning programme put in place to reduce accumulating fuel loads. These investigations show that habitat fragmentation can be caused by different factors at different spatial scales. At the continental scale, it was found that climate played a dominant role in influencing the fragmented distribution of I. obesulus but vegetation change during the past two centuries has also had a profound impact on the availability of habitat. Within south-eastern South Australia, the species??? regional scale distribution is constrained by climate and also by soil and vegetation patterns. Dramatic change to its regional distribution occurred in the 20th century as a result of the clearance of native vegetation for planting pastures, crops and pines. Fragmentation at the regional scale has resulted in the remaining habitat being reduced to small, isolated, remnant patches of native vegetation. At the local scale it was found that variables which disrupt the continuity of I. obesulus habitat within remnants include vegetation cover in the 0-1 m stratum, abundance of Xanthorrhoea australis and soil texture. For a subset of sites located in one landsystem of the study area, named Young, the age of vegetation since it was last burnt was also found to be a significant variable, with vegetation 10-14 years old since burning providing the most suitable habitat. Spatial modelling of two scenarios for prescribed burning over 15 years revealed that the use of fire as a habitat enhancement tool will be complicated and require a detailed understanding of the factors that cause natural fragmentation in the distribution of I. obesulus at the local scale. A further conclusion of the study was that ecological relationships between species and their habitats require careful interpretation of multi-scaled datasets and conservation plans for endangered species ought to be made at multiple spatial scales. Future research directions are identified including the linking of multi-scaled habitat fragmentation models to genetic studies of the species throughout its range.
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Reproductive success, dimorphism and sex allocation in the brown falcon Falco berigoraMcDonald, Paul, Paul.McDonald@latrobe.edu.au January 2003 (has links)
This project describes various aspects of the breeding ecology and behaviour of the brown falcon Falco berigora, a common but poorly study Australian raptor. In particular it examines (a) the main influences on reproductive success; (b) tests predictions of theories proposed to explain the evolution and maintenance of sexual size dimorphism (RSD; females the larger sex) in raptors; and (c) investigates sex allocation patterns in the light of current sex ratio and parental investment theory. The study was conducted between July 1999 and June 2002 approximately 35 km southwest of Melbourne, at the Western Treatment Plant (WTP), Werribee (38°0S 144°34E) and surrounds, a total area of approximately 150 km2.¶
· In all plumage and bare part colouration of 160 free-flying falcons was described. The majority of variation in these characters could be attributed to distinct age and/or sex differences as opposed to previously described colour morphs.¶
· Nestling chronology and development is described and formulae based on wing length derived for determining nestling age. An accurate field-based test for determining nestling sex at banding age is also presented.¶
· Strong sex role differentiation was apparent during breeding; typical of falcons females performed most parental duties whilst males predominantly hunted for their brood and partner. Based on observations of marked individuals, both sexes of brown falcons aggressively defended mutual territories throughout the year, with just 10% of each sex changing territories during the entire study period. Males performed territorial displays more frequently than females, the latter rarely displaying alone.¶
· The diet of the population as a whole was very broad, but within pairs both sexes predominantly specialised on either lagomorphs, small ground prey (e.g. house mice Mus musculus), small birds, large birds or reptiles, according to availability.¶
· Reproductive parameters such as clutch size and the duration of parental care were constant across all years, however marked annual differences in brood size and the proportion of pairs breeding were evident.¶
· Age was an important influence upon reproductive success and survival, with immature birds inferior to adults in both areas. However, interannual differences were by far the most influential factor on breeding success and female survival. Heavy rain downpours were implicated as the main determinant of reproductive success and adult female mortality in a population largely devoid of predation or human interference.¶
· Female-female competition for territorial vacancies was intense; larger adult females were more likely to be recruited and once breeding fledged more offspring. In contrast, male recruitment and breeding success was unrelated to either body size or condition indices, although smaller immature males were more likely to survive to the next breeding season. This directional selection is consistent only with the predictions of the intrasexual competition hypothesis.¶
· Despite marked RSD (males c. 75% of female body mass), throughout the nestling phase female nestlings did not require greater quantities of food than their male siblings. However, female parents fed their last-hatched sons but not daughters, resulting in the complete mortality of all last-hatched female offspring in focal nests. Given last-hatched nestlings suffered markedly reduced growth rates and female, but not male, body size is important in determining recruitment patterns, the biased allocation amongst last-hatched offspring is likely to reflect differing benefits associated with investing in small members of each sex, consistent with broad-scale Trivers-Willard effects. Recruitment patterns support this, with surviving last-hatched females, in contrast to males, unable to gain recruitment into the breeding population upon their return to the study site.¶
Thus selection appears to act at the nestling, immature and adult stages to maintain RSD in the focal population. Larger females were favoured in the nestling phase, at recruitment and once breeding had greater reproductive success. In contrast, selection favoured a reduction or maintenance of immature male size as smaller birds had a greater chance of survival in the year following recruitment than their larger counterparts; thereafter male size was unimportant. Together, this directional selection favouring increased female competitive ability is consistent only with the predictions of the intrasexual competition hypothesis, which appears the most probable in explaining the maintenance and perhaps evolution of RSD in raptors.
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Transport et bruit quantique dans les fils mésoscopiquesTorrès, Julien 13 September 2001 (has links) (PDF)
Un conducteur quantique est bien caractérisé par sa conductance donnée par la formule de Landauer. Mais le bruit contient davantage d'informations que la conductance : il mesure les fluctuations temporelles du courant autour de sa valeur moyenne. De plus, le signe des corrélations de bruit est lié à la statistique des porteurs de charge. Dans une jonction entre un métal normal et un supraconducteur, le bruit présente une singularité à la fréquence Josephson, signature de la charge 2e des paires de Cooper impliquées dans le transport. Lorsque la tension appliquée est supérieure au gap du supraconducteur, la courbe du bruit exhibe des singularités à plusieurs fréquences auxquelles on peut associer un processus de réflexion ou de transmission. L'analogue fermionique de l'expérience d'Hanbury-Brown et Twiss avec un supraconducteur permet d'observer à la fois des corrélations positives et négatives dans un même système. Maintenir une différence de potentiel entre les deux extrémités d'un fil crée une situation relevant de la thermodynamique hors de l'équilibre. Formellement, on peut se ramener à un calcul à l'équilibre et écrire une théorie des perturbations grâce à la méthode de Keldysh. La théorie des liquides de Luttinger décrit les systèmes unidimensionnels d'électrons en interaction. Le Hamiltonien peut se mettre sous forme quadratique grâce à la bosonisation. D'autre part, un liquide de Luttinger chiral constitue un bon modèle des états de bord de l'effet Hall quantique fractionnaire. Grâce au formalisme de Keldysh, on peut retrouver une formule de type Schottky et identifier la charge des quasiparticules de Laughlin.
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Comportement des tunnels dans les milieux rocheux de faibles caractéristiques mécaniquesRojat, Fabrice 24 November 2010 (has links) (PDF)
Les projets de tunnels dans des milieux rocheux de faibles caractéristiques mécaniques, usuellement regroupés sous l'appellation sols indurés roches tendres (S.I.R.T.), se heurtent à de multiples difficultés. Ces matériaux présentent des spécificités de comportement qui les rendent atypiques dans les contextes usuels de la mécanique des sols comme de la mécanique des roches, compliquant les dimensionnements et pouvant engendrer des surcoûts importants pour les maîtres d'ouvrage. En se limitant aux S.I.R.T. modélisables par une approche continue, la non-linéarité du critère de rupture, les couplages hydromécaniques et la dépendance de la déformabilité à l'état de contrainte apparaissent comme des traits de comportements susceptibles d'influencer significativement la phase de creusement (équilibre à court terme). Bien que ces propriétés puissent être prises en compte de manière adéquate dans des modèles numériques, la pratique des calculs de tunnel a montré de longue date l'intérêt des méthodes simplifiées comme l'approche convergence-confinement. Elles permettent un prédimensionnement raisonnablement représentatif au moyen de formulations peu complexes et favorisent la réalisation d'études de sensibilité grâce à leur mise en œuvre simple et rapide. À partir d'une approche de type " milieux poreux ", prenant en compte la compressibilité des différents constituants du matériau, et d'une représentation adimensionnelle du critère de rupture de Hoek-Brown (incluant les régimes d'arête), de nouvelles formulations permettant le calcul des courbes caractéristiques du terrain sont donc présentées. Après s'être intéressé dans un premier temps à la seule non-linéarité du critère de rupture, avec un milieu monophasique, une complexification progressive du problème est mise en œuvre pour prendre en compte des situations biphasiques drainées ou non drainées. À chaque fois une résolution complète est proposée, aboutissant à des formulations explicites ou à des équations intégrables aisément par une méthode numérique à un pas. Un outil sous forme de tableur, directement utilisable et démontrant la simplicité de mise en œuvre des solutions établies, est systématiquement fourni. Le cas non drainé est ensuite complété par un schéma de calcul intégrant une élasticité non-linéaire de Fahey-Carter, avec la méthode des matrices de transfert. La partie finale du travail permet d'aborder l'applicabilité de ces développements analytiques à un cas réel, le tunnel d'Arbus. Elle souligne quelques difficultés de détermination de paramètres à partir de campagnes d'essais " standard " et insiste sur la variabilité naturelle des matériaux dans une géologie molassique du piémont pyrénéen. Ce contexte met en relief les avantages des méthodes développées : outre une représentation plus satisfaisante du comportement du milieu, elles permettent à peu de frais d'identifier les paramètres les plus influents sur l'équilibre massif - soutènement et d'aborder la problématique des incertitudes dans le dimensionnement. Les calculs font également ressortir l'intérêt des modèles à élasticité non linéaire, avec une prise en compte plus appropriée de la déformabilité du matériau mais aussi une réduction de la sensibilité du modèle à la variabilité des paramètres élastiques. Les approches présentées conservent néanmoins certaines limites, comme la nécessaire distinction des équilibres court terme et long terme, l'hypothèse de contrainte initiale hydrostatique qui se révèle au final assez forte et le problème de la représentation du soutènement qui mériterait d'être davantage approfondi même si des méthodes acceptables sont d'ores et déjà disponibles dans la littérature.
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Kantzonsvegetationens inverkan på dieten hos öring (Salmo trutta) i en skogsbäckAxelsson, Tomas January 2008 (has links)
<p>Effekterna på öringens (Salmo trutta) diet till följd av en avverkning av kantzonsvegetationen har undersökts i ett fältexperiment, där två av de potentiella effekterna av en skogsavverkning simulerades. Fokus låg på de två faktorerna ökad ljusinstrålning och minskat nedfall av terrestra evertebrater. Ökad ljusinstrålning har simulerats med hjälp av montage av lysrör och nedfall av terrestra evertebrater med hjälp av plasttält. Frågeställningarna rör andelen terrester föda i olika behandlingar och årstider, dietskillnader mellan äldre och yngre öringindivider, skillnader i mängden akvatisk föda vid ökad ljusinstrålning samt en taxonomisk översikt av dietens sammansättning. Signifikanta skillnader mellan behandlingarna fanns, där individerna i kontrollbehandlingen åt signifikant mer terrester föda än individer i tältbehandlingen och den kombinerade tält- och ljusbehandlingen. Signifikanta skillnader fanns även mellan provtagningstillfällena där en högre andel terrester föda återfinns senare på säsongen. Inga signifikanta skillnader fanns med avseende på andelen terrester föda mellan äldre och yngre individer, ej heller mellan mängd akvatisk föda mellan de olika behandlingarna. Den akvatiska födan var mer varierad och divers än den terrestra, och daggmaskar (Lumbriculidae) var en mycket vanlig födopartikel.</p> / <p>The effects on the diet of brown trout (Salmo trutta) of a clear cutting of the riparian vegetation has been investigated in a field-experiment, where two of the potential effects of a clear cut were simulated. The focus was placed on the two factors increased light and input of terrestrial invertebrates. The increase of ligth was manipulated by placing fluorescent lights over the brook and the input of terrestrial invertebrates was manipulated by placing plastic tents over the brook. Issues discussed are the percentage terrestrial food in the different treatments and at the different times of sampling, differences in the percentage terrestrial food between older and younger individuals of brown trout, differences in the amount of aquatic food in the light-treatment and a taxonomic summary of the composition of the diet. There were significant differences between the the different treatments, where the individuals in the control treatment ate significantly more terrestrial food as compared to the individuals in the tent and in the combined light and tent treatment. There was also a significant difference between the different times of sampling, more terrestrial food was consumed later in the season. No sigificant differences were detected between older and younger individuals concerning the percentage of terrestrial food eaten, nor between the different treatments concearning the amount of aquatic food consumed. The aquatic food showed a wider variation and was more diverse as compared to the terrestrial food, and earthworms (Lumbriculidae) was a very common food item.</p>
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Påverkan av tillskott av död ved och reducerat evertebratnedfall på öringens (Salmo trutta L.) diet i en skogsbäck / The effect of a supplement of woody debris and reduced input of terrestrial invertebrates on the diet of brown trout (Salmo trutta L.) in a forest streamZetterqvist, David January 2008 (has links)
<p>Det svenska skogsbruket har lett till minskade vedmängder i skogsbäckarna. Detta kan undvikas genom att orörda kantzoner lämnas. Kantzonsvegetatioen har även visats påverka nedfallet av terrestra evertebrater, vilket visats minska andelen terrestra evertebrater i laxfiskars diet. Ofta lämnas dock inga kantzoner. Vedmängden kan återställas genom ett vedtillskott. Ett vedtillskott leder till ökat antal och högre biomassa av laxfiskar och högre mängd bottenlevande evertebrater i de behandlade områdena. Nyligen nedsänkt ved koloniseras snabbt av evertebrater. I denna studie undersöktes effekterna av ett vedtillskott och reducerat evertebratnedfall på öringens (Salmo trutta) diet i ett fältexperiment i en skogsbäck, från juni till augusti 2007. Tillskottet av ved ledde till signifikant högre totalbiomassa i dieten i juli men inte i augusti Vedtillskottet ledde även till en lägre andel Dipteraadulter i dieten i juli. Reduktionen av evertebratnedfallet hade ingen påverkan på den totala andelen terrestra evertebrater i öringens diet. Reduktionen gav dock upphov till lägre Formicidae och Dipteraadult andel, i juli och lägre Formicidaebiomassa i dieten i juli. En kombination av ett vedtillskott och reducerat evertebratnedfall hade ingen påverkan på öringens diet. Slutsatserna var att den högre dietbiomassan vedtillskottet gav upphov till i juli, troligen berodde på en initial ökning i bytesförekomsten. Att andelen terrestra evertebrater i dieten inte minskade när evertebrat nedfallet reducerades berodde troligen på att reduktionen inte var tillräckligt stor för att ett dietskifte skulle ske. Frånvaron av signifikanta skillnader för behandlingen med både vedtillskott och reducerat nedfall berodde antagligen på att reduktionen i nedfallet motverkade effekten ett vedtillskott gav på dietbiomassan.</p> / <p>The Swedish forestry has caused a decrease in amounts of woody debris in the forest streams. This can be avoided by leaving an untouched riparian strip. A lack of riparian strip vegetation has also been shown to reduce the input of terrestrial invertebrates, which has been shown to reduce the proportion of terrestrial invertebrates in the diet of salmonides. In many cases such strips are not left. The amount of woody debris in a stream can be restored by a supplement of woody debris. That has been shown to lead to higher salmonide abundance and biomass and higher abundance of benthic invertebrates in the treated area. It has also been shown that newly submerged wood is rapidly colonised by invertebrates. In this study the effects of a supplement of woody debris and reduced input of terrestrial invertebrates on the diet of brown trout (Salmo trutta) was examined in a field experiment. The study took place with enclosures in a Swedish boreal stream, from June to August 2007. Introduction of woody debris caused a significantly higher diet biomass in July but not in August. The wood treatment also caused a decrease in the proportion of Diptera adults in the diet in July. The reduction of terrestrial invertebrate input didn’t affect the total proportion of terrestrial invertebrates in the trout diet. Nevertheless there was a significant decrease in the proportion and biomass of Formicidae and the proportion of Diptera adults in the diet in June. The combination of both treatments didn’t have any significant effect on the trout diet. The conclusions were that the higher diet biomass in July caused by woody debris addition, probably was due to an initial increase in the abundance of available aquatic invertebrates. The lack off effect from the reduced input of terrestrial invertebrate on the trout diet, was most likely due to the fact that the decrease in terrestrial invertebrate input probably wasn’t large enough to cause a dietary switch. The lack of effect of a combination of the two treatments indicated that the reduced input of terrestrial invertebrates cancelled out the effect of the added woody debris.</p>
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Apologising in British EnglishDeutschmann, Mats January 2003 (has links)
<p>The thesis explores the form, function and sociolinguistic distribution of explicit apologies in the spoken part of the British National Corpus. The sub-corpus used for the study comprises a spoken text mass of about five million words and represents dialogue produced by more than 1700 speakers, acting in a number of different conversational settings. More than 3000 examples of apologising are included in the analysis.</p><p>Primarily, the form and function of the apologies are examined in relation to the type of offence leading up to the speech act. Aspects such as the sincerity of the apologies and the use of additional remedial strategies other than explicit apologising are also considered. Variations in the distributions of the different types of apologies found are subsequently investigated for the two independent variables speaker social identity (gender, social class and age) and conversational setting (genre, formality and group size). The effect of the speaker-addressee relationship on the apology rate and the types of apologies produced is also examined.</p><p>In this study, the prototypical apology, a speech act used to remedy a real or perceived offence, is only one of a number of uses of the apology form in the corpus. Other common functions of the form include discourse-managing devices such as request cues for repetition and markers of hesitation, as well as disarming devices uttered before expressing disagreement and controversial opinions.</p><p>Among the speaker social variables investigated, age and social class are particularly important in affecting apologetic behaviour. Young and middle-class speakers favour the use of the apology form. No substantial gender differences in apologising are apparent in the corpus. I have also been able to show that large conversational groups result in frequent use of the form. Finally, analysis of the effects of the speaker-addressee relationship on the use of the speech act shows that, contrary to expectations based on Brown & Levinson’s theory of politeness, it is the powerful who tend to apologise to the powerless rather than vice versa.</p><p>The study implies that formulaic politeness is an important linguistic marker of social class and that its use often involves control of the addressee. </p>
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