The procerebrum of terrestrial molluscs is an important processing centre for olfaction. While the physiology of the procerebrum is relatively well characterized, the procerebrum's structure and organization has not been previously investigated in detail. The goal of this thesis is to better characterize the structural organization of the procerebrum and to understand how it compares with other olfactory systems. / The morphology of the procerebral neurons in the snail Helix aspersa was investigated through intracellular injections of biocytin. The population of cells is heterogeneous, but no formal categorization of neuronal types was possible. The main difference among cells lies in the placement of the cells' neurites. Furthermore, contradicting previous results, certain neurons were found to have neurite projections outside the procerebrum, travelling as far as the contralateral cerebral ganglion. / To investigate if differences in sites of arborization represent functional differences, the distribution of synaptic contacts on labelled cells was studied using serial sections and electron microscopy. Neurons with different sites of arborization have distinct patterns of synapse distribution. Cells with arborizations in the procerebrum but not in the internal mass have large varicosities specialized for output. Cells that arborize in the internal mass or outside the procerebrum have mostly input synapses proximal to the soma and mostly output synapses in the terminal region of the neurites. These latter cells appear to transmit information from the procerebral cell body mass to other brain regions. The implications of these data are, firstly, that the procerebrum directly distributes processed information throughout the nervous system. Secondly, the procerebral neuron population may be divisible into two subgroups: intrinsically arborizing interneurons and projection neurons. / These results suggest a novel mechanism by which compartmentalization could be achieved in the procerebrum. Compartmentalization is believed to be important for processing olfactory information, is present in most olfactory centres but has not previously been described in the molluscan olfactory system. I propose that varicosities on the local interneurons generate foci of activity in the procerebrum which, in turn, activate specific subsets of output neurons, similar to what happens in other olfactory systems.

Darbe taikyta Norvaišos ir Salopk (2002) metodologija funkcijos šiurkštumui nagrinėti remiantis modifikuotu funkcijos grafiko dėžučių skaičiaus indeksu. Funkcijos šiurkštumas nusakomas p-variacijos indeksu, kuris prie tam tikrų sąlygų lygus fraktalo dimensijai. Darbe ištirtos tiesinės regresijos, kuri vertina p-variacijos indeksą, liekanos ir pasiūlytas būdas kaip išpildyti balto triukšmo prielaidas. Rezultatai apibendrinti Monte Carlo procedūra. Sukonstruoti p-variacijos indekso pasikliautinieji intevalai -stabiliam ir trupmeniniam Brauno judesio procesams. Ištirtas p-variacijos indekso kintamumas laike „Vallourec” akcijų kainos procesui. / To estimate the roughness of the sample function the methodology introdused in Norvaiša and Salopek (2002) was applied. The roughness is defined as p-variation index of the sample function graph. Methodology is based on linear regression of the oscilation index. This master thesis tests the assumptions of linear regression residuals and constructs estimator which fulfill these assumptions. The model was used for the generated α-stable process and fractional Brownian motion. Conclusions are generalized using Monte-Carlo procedure. The confidence intervals for the p-variation index was constructed making assumption that the process is the realisation of -stable or fractional Brownian motion. The p-variation index was estimated for the „Vallourec” stock price data, sampled at irregular time. In addidion the variability in time of p-variation index was studied for different segments of intervals.

An alkaline extract of the brown seaweed, Ascophyllum nodosum (ANE) increases plant growth and imparts resistance against biotic stresses. However, little is known of the effects of ANE on insects. Myzus persicae, green peach aphid (GPA), and Arabidopsis model were used to determine whether application of ANE confers protection from GPA infestation. GPA colonization increased in ANE treated plants, associated with improved biomass. However, ANE treated plants exhibited less cell death and also showed a greater ability to recover from GPA injury. Lower expression of SAG13, SAG21 and CHL1 and a higher expression of ARR5 was observed in ANE treated plants. Taken together, gene expression along with lower cell death suggests ANE may delay senescence in Arabidopsis. Delayed senescence in Arabidopsis following ANE treatment may be a result of increased cytokinin activity. Increased GPA numbers could be, at least in part, due to delayed senescence in Arabidopsis following ANE treatment.

<p>In the decades following the English Civil War, as the Anglophone world began transitioning to a social order structured by market and finance capitalism, the word cultivation, which earlier had referred exclusively to agricultural processes, acquired increasingly figurative meanings referring to the development of an individual's mind, faculties, and manners. This augmentation of meaning reflected the development of new conceptions of property as an essential feature of personhood that had begun to alter the definition of subjectivity. The circulation of such figurative meanings coincides with the rise of print culture, the development of a literary public sphere, and the professionalization of writing in the eighteenth century. These cultural developments suggest the relative ease with which the new conception of property expressed as literary personality coexisted alongside other forms of capital in Britain. Literary criticism of the last forty years, including the work of Raymond Williams, Clifford Siskin, Jerome Christensen, and Thomas Pfau, has accounted for the many ways in which possessing literary cultivation served the development of a middle-class economy and ideology in eighteenth-and-nineteenth century Britain. Though the figurative meaning of cultivation appears throughout American literature of the long nineteenth century, thus attesting to the concept's transatlantic migration and adaptation to the socio-political climates of the New World, no significant studies of American literature have considered the role literary cultivation itself plays in shaping American ideas of personality. My study begins to facilitate an understanding of how modern definitions of property affected and effected early American literary culture.</p><p>By placing American literature of the long nineteenth century in a transatlantic context, I show how five works by De Crevecoeur, Franklin, Equiano, Brockden Brown, and Margaret Fuller model the relationship between real and metaphorical cultivation at the level of both form and narrative content. I argue that within these works literary personality appears as a threat to the American character unless it directly facilitates the acquisition of real property. That in an American context figurative cultivation is at all times subordinated to real cultivation suggests a suspicion of intellectual development at the very foundations of American culture. I draw on new work in early American literature, eighteenth-century studies, British Romanticism, and on a tradition of Marxist critique to read American personality not as an exceptional and isolated development of the revolutionary era, but as a transatlantic migration of cultural forms and conceptions that adapt and mutate upon arriving on New World soil. To understand these migrations and mutations, I map the importation of European aesthetic concepts and literary sources within American productions. My readings make sense of the contradictions within the anti-literary American ideology often articulated in the content of works, whose forms nevertheless reveal a comprehensive engagement with literary history. Doing so allows me to demonstrate the complex ways in which early American authors depicted literary cultivation as either a means of acquiring real property or as a moral redress against the self interest of a speculative economic culture.</p> / Dissertation

Common brown colour in natural diamond forms by plastic deformation during storage in the subcontinental lithospheric mantle (SCLM). Dislocation movement generates vacancies, which aggregate into clusters of perhaps 30–60 vacancies. Positron annihilation lifetime spectroscopy (PALS) and electron energy loss spectroscopy (EELS) support such vacancy clusters as the cause of brown colour. Brief treatment in a high-pressure–high-temperature (HPHT) vessel at 1800–2700 °C can destroy the brown colour. There has been speculation that similar colour removal should occur continuously at depth in the SCLM. Diamonds are stored at 900–1400 °C in the SCLM, according to inclusion thermometry. The effect of temperature on the time required to destroy brown colour has been calculated from published data. The activation energy for the breakup of vacancy clusters is a critical component. The time required to destroy brown colour in the SCLM is significant at the scale of geological time. Brown diamonds should easily maintain their colour for millions of years during cooler mantle storage at or below about 1000 °C. Warmer temperatures toward the base of the lithosphere may be able to reduce or eliminate brown colour within thousands of years. The survival of brown colour in the lithospheric mantle does not require the colour to be formed late in the storage history nor does it require metastable storage in the graphite stability field. Crystal strain is preserved upon loss of brown colour during HPHT treatment. Inhomogeneous crystal strain was measured in 18 natural diamonds using micro-X-ray diffraction (μXRD) χ-dimension peak widths. There is a correlation between strain and depth of brown colour. None of the colourless diamonds examined have high strain, as should be expected for a diamond that has gained and lost brown colour. This suggests that removal of brown colour is not a common natural occurrence. Infrared spectroscopy was used to determine nitrogen concentration and aggregation state in 60 natural diamonds. A loose association was found between brown colour and lower total nitrogen content. Within single diamonds, regions with less nitrogen tend to exhibit more anomalous birefringence due to strain. Colour zoned diamonds tend to have less nitrogen in the darker brown regions. This supports the hypothesis that diamonds with less nitrogen are more susceptible to plastic deformation and the development of brown colour. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2009-09-17 17:10:11.078

The morphology of C3, a motoneuron mediating the tentacle withdrawal reflex, was investigated in the snail Helix aspersa by intracellular injections of the tracers Neurobiotin and biocytin. Axonal projections were identified in the optic nerve, the olfactory nerve, the internal peritentacular nerve, the external peritentacular nerve, the cerebral-pedal connective and the cerebral commissure. A rare characteristic of the cell was the multibranching of axons in the neuropil and the exiting of this bundle of fibres into the cerebral-pedal connective. Dendritic arborizations were observed branching from the cell body, the axon hillock and the dorsal main axon. In addition, tufts of dendrites were seen to branch from the ventral axon. Based on its morphology, C3 is probably a central component in the avoidance behaviour, receiving sensory input at extensive dendritic sites and sending axons to a number of key effector sites to co-ordinate the chain of reactions that constitutes the snail's avoidance behaviour.

No description available.

There are two distinct types of adipose tissue which have different functions within the body, white (WAT) and brown (BAT). Browning of WAT occurs with increases in the WAT sympathetic nervous system (SNS) drive. In this regard we previously reported that melatonin (MEL) stimulation of MEL receptor 1A (MEL1a) within the SNS outflow to the WAT might be implicated in a naturally-occurring reversal of obesity (by ~30% of total body fat). Therefore, in this study we tested the hypothesis that MEL causes browning of WAT through the stimulation of SNS drive to WAT. This was done by comparing specific browning and lipolytic markers in WAT following 10 weeks of MEL treatment, short day housing (SD), and long day housing with saline injections (LD+VEH). Browning effects of a 5 day treatment of a β3-adrenergeric (β3 AR), CL 316, 243, were also measured. We found that CL 316, 243, MEL treatment, and SD housing had increased expressions of browning markers within WAT and lipolytic activity in MEL treated animals was increased in specific WAT.

The first year of life is one of the main survival bottlenecks for many fish species. Individual traits affecting survival can be morphological, physiological or behavioural. Body size, growth rate and activity have all been found to affect fitness in different organisms. However, the effects of these traits on fitness in natural conditions and for underyearlings are poorly investigated. In this study we attempted to induce compensatory growth in laboratory conditions in natural populations of brown trout fry (Salmo trutta). It was performed by exposing the fry to a period of restricted resources followed by a period of refeeding. Two behavioural trials were conducted on each individual where activity level was scored. All fish were subsequently released in their native stream and recaptured after a month to check for survival. We found that high individual activity level in an open field context increased the probability of survival under natural conditions. The importance of body size for survival decreased over time, and thus, with fish size. Full compensation was detected in body condition, while only partly compensation in weight and no compensation in length were detected during the experimental periods. Our results suggest that a brown trout fry’s individual activity level is repeatable and can be an important trait for selection in nature. The instable interactions between activity and life-history traits indicate environmental effects on these interactions. Furthermore, if body size is not the only trait affecting survival, compensation in body structures may not be a fast response to increase fitness after a period of growth depression.

There is no abstract available for this dissertation.