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Genealogical Correspondence of Learning and Memory Centers across PhylaWolff, Gabriella Hannah January 2015 (has links)
Across bilaterian phyla, learning and memory allows animals to benefit from central-place foraging, return to ideal food sources, choose mates and avoid dangerous or harmful external stimuli. Although these behaviors are comparable in both vertebrate and invertebrate animals, it is unknown whether or not they are mediated by homologous brain structures. In insects, paired, lobate forebrain structures called mushroom bodies receive input from primary sensory neuropils and are necessary for learning and memory, whereas in crustaceans, this behavior is mediated by paired, compact forebrain structures called hemiellipsoid bodies. Mammalian learning and memory is mediated by the paired, horn-shaped hippocampi, which also receive sensory input and are likewise situated in the forebrain. Did these structures evolve independently along with the ability for animals to learn and remember associations and places? Alternatively, the hypothesis posited in this dissertation is that the last bilaterian ancestor already possessed the ability to learn and adapt to its environment, behavior mediated by paired forebrain structures that evolved divergently into the elaborated forms we observe in extant, crown-group taxa. This hypothesis is investigated and discussed in the following reports: 1) a review of insect brain anatomy and functional connectivity, including a description of mushroom bodies, in the context of arthropod evolution; 2) a comparison of neuroanatomy, circuitry, and protein expression between insect mushroom bodies and Malacostracan crustacean hemiellipsoid bodies, using cockroaches and Caribbean hermit crabs as representatives of their classes; 3) a deeper investigation of the fine structure of neuronal organization in the hemiellipsoid body of the Caribbean hermit crab, focusing on electron microscopical observations and comparisons to the ultrastructure of the fruit fly mushroom body; 4) a survey of four invertebrate Phyla, employing the strategy of comparing neuroanatomy and protein expression to investigate whether higher order forebrain structures in these animals were inherited from a common ancestor; 5) a comparison of neuroanatomy, connectivity, and protein expression in insect mushroom bodies and mammalian hippocampus, including a survey of PKA-Cα in these and corresponding structures across the Chordata. The total evidence suggests that a common Bilaterian ancestor possessed a center that evolved to become mushroom bodies in invertebrates and hippocampus in vertebrates.
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Visual Specializations in the Brain of the Split-Eyed Whirligig Beetle Dineutus sublineatusLin, Chan January 2014 (has links)
Whirligig beetles are gregarious aquatic insects living on the water surface. They are equipped with two separate pairs of compound eyes, an upper aerial pair and a lower aquatic pair, but little is known about how their brains are organized to serve such an unusual arrangement. In the first study of this dissertation, I describe the neural organization of their primary visual centers (the optic lobes) of the larval and adult whirligig beetle Dineutus sublineatus. I show that the divided compound eyes of adult beetles supply elaborate optic lobes in the brain that are also split into an upper and a lower half, each optic lobe comprising an upper and lower lamina, an upper and lower medulla, and a partly split bilobed lobula. The exception is the fourth neuropil, the lobula plate. Studies of their development show that the lobula plate Anlagen serving the upper and lower eyes develop at different rates and thus different developmental stages. The upper lobula plate develops precociously in the larva and is thought to process information that enables subaquatic ambush hunting. During metamorphosis the upper lobula plate degenerates and is lost as are the larval stemmatal eyes supplying it. The lower lobula plate develops later, during metamorphosis, and is present in the imago where it is supplied by the lower compound retina. By analogy with dipteran lobula plates it is proposed to support subaquatic locomotory balance. In the subsequent study, I describe the neural organization of the whirligig beetle’s mushroom bodies, a pair of prominent brain centers in the forebrain that are best known for their roles in higher olfactory processing and olfactory-based learning and memory. I found that unlike other insects examined so far, the calyces of the whirligig beetle’s mushroom bodies are exclusively supplied by visual neurons from optic lobe neuropils serving the pair of upper aerial compound eyes, thereby showing a complete modality switch from olfaction to vision in this brain center. These findings, along with multiple evidence from hymenopteran insects and cockroaches, suggest that insect mushroom bodies are not merely olfactory-related but may be involved in visual tasks, such as memory of place. In the last study, I describe experiments to demonstrate that a group of D. sublineatus is able to learn their location with respect to visual cues provided from above the water line, and simultaneously establish and maintain their relative positions with each other within the group. These results provide an explanation as to how a collective, such as several hundred whirligig beetles, can maintain cohesion and remember landmarks that "anchor" the collective at a particular location in a pond or stream. Using techniques in comparative neuroanatomy, this dissertation documents visual specializations of an insect brain that has evolved to suit a unique group-living lifestyle on the water surface. In addition, the spatial learning paradigm described in the third study provides an essential assay for future lesion studies to determine if mushroom bodies are indeed required for visually mediated spatial learning and memory.
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Learning and Memory and Supporting Neural Architecture in the Cockroach, Periplaneta americanaLent, David D January 2006 (has links)
The cockroach, with its large brain and physiological resilience, holds many advantages for the development of behavioral paradigms. The work presented here provides a foundation for, and describes the results of, the implementation of studies of neural correlates of learning and memory on restrained animals.Using the antennal projection response (APR) as an indicator of learning and retention, several learning paradigms have been developed. A visual-olfactory associative and a gustatory-olfactory aversive conditioning paradigm demonstrated a plastic behavior that could be driven in an intact and immobilized cockroach. Conditioning the APR to a visual cue paired with an olfactory cue characterized the role of unilateral and bilateral olfactory input in learning and memory. While unilateral olfactory input is sufficient to learn a visual-olfactory association, bilateral olfactory input is necessary for long-term retention of the association. This comparison identified a critical time period in which memory is consolidated. This time period was subsequently used to analyze gene expression during memory consolidation.The split-brain cockroach preparation was developed to investigate what parts of the brain are necessary and sufficient for learning and retention of a visual-olfactory association; this preparation was also used to examine learning-induced changes in test tissue versus control tissue provided by the same animal. Evidence suggests that half of a brain is sufficient for a visual-olfactory association to be established and sufficient for retention of that association between 12 and 24 hours. However, the entire brain is necessary for long-term memory to be established. Using the split-brain cockroach simultaneously as the control and the test subject, learning-induced alterations in the microglomerular synaptic complexes of the calyces were identified in the trained half, but not in the naïve half.Using the APR, spatial learning and memory was examined. Multiple representations of space were revealed in the brain of the cockroach. Cockroaches represent space in terms of an olfactory gradient map, as well as the visuospatial relationship between objects. When both representations of space can be utilized by the cockroach to localize a cue, the positional visual cue is the one that determines the behavioral response.
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Dionysian Semiotics: Myco-Dendrolatry and Other Shamanic Motifs in the Myths and Rituals of the Phrygian MotherAttrell, Daniel 16 August 2013 (has links)
The administration of initiation rites by an ecstatic specialist, now known to western scholarship by the general designation of ‘shaman’, has proven to be one of humanity’s oldest, most widespread, and continuous magico-religious traditions. At the heart of their initiatory rituals lay an ordeal – a metaphysical journey - almost ubiquitously brought on by the effects of a life-changing hallucinogenic drug experience. To guide their initiates, these shaman worked with a repertoire of locally acquired instruments, costumes, dances, and ecstasy-inducing substances. Among past Mediterranean cultures, Semitic and Indo-European, these sorts of initiation rites were vital to society’s spiritual well-being. It was, however, the mystery schools of antiquity – organizations founded upon conserving the secrets of plant-lore, astrology, theurgy and mystical philosophy – which satisfied the role of the shaman in Greco-Roman society. The rites they delivered to the common individual were a form of ritualized ecstasy and they provided an orderly context for religiously-oriented intoxication.
In the eastern Mediterranean, these ecstatic cults were most often held in honour of a great mother goddess and her perennially dying-and-rising consort. The goddess’ religious dramas enacted in cultic ritual stressed the importance of fasting, drumming, trance-inducing music, self-mutilation, and a non-alcoholic ritual intoxication. Far and wide the dying consort worshiped by these cults was a god of vegetation, ecstasy, revelation, and salvation; by ingesting his body initiates underwent a profound mystical experience. From what limited information has survived from antiquity, it appears that the rites practiced in the eastern mystery cults were in essence traditional shamanic ordeals remodeled to suit the psychological needs of Mediterranean civilization’s marginalized people. This paper argues that the myths of this vegetable god, so-called ‘the Divine Bridegroom,’ particularly in manifestation of the Phrygian Attis and the Greek Dionysus, is deeply rooted in the life-cycle, cultivation, treatment, consumption of a tree-born hallucinogenic mushroom, Amanita muscaria. The use of this mushroom is alive and well today among Finno-Ugric shaman and this paper explores their practices as one branch of Eurasian shamanism running parallel to, albeit in a different time, the rites of the Phrygian goddess. Using extant literary and linguistic evidence, I compare the initiatory cults long-assimilated into post-agricultural Mediterranean civilization with the hallucinogen-wielding shaman of the Russian steppe, emphasizing them both as facets of a prehistoric and pan-human magico-religious archetype.
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Extending Shelf Life of Sliced Mushrooms (Agaricus bisporus) by using Vacuum Impregnation and Electron-beam IrradiationSevimli, Zeynep 02 October 2013 (has links)
Mushrooms are one of the protein rich foods, however they have a short pro-harvest life (2 to 3 days) compared to most vegetables. The aim of this study was to evaluate whether applying an anti-browning solution using vacuum impregnation and then electron beam irradiation can be used to extend the shelf life of fresh-cut mushrooms (Agaricus bisporus).
Solutions made with (a) 2% ascorbic acid + 1% calcium lactate, (b) 2% citric acid + 1% calcium lactate, (c) 1% chitosan + 1% calcium lactate, and (d) 1% calcium lactate were used to impregnate mushroom slices at different vacuum pressures, vacuum pressure times, and atmospheric restoration times. Mushrooms were also irradiated at a dose of 1 kGy using a 1.35 MeV e-beam accelerator and their quality was evaluated in terms of color, texture, and microbial growth during 15 days storage at 4 degrees C.
The best vacuum impregnation treatment was the 2% ascorbic acid and 1% calcium lactate solution using a vacuum pressure of 50 mmHg for 5 minutes and an atmospheric restoration time of 5 minutes.
The control (not treated) and impregnated samples lost their structure (softening) during storage. The irradiated samples lost their firmness by day 4 of storage. The addition of calcium lactate to the samples during the treatment helped to keep the product’s texture during the 15 days storage time.
Color of the mushrooms changed during storage for all the control and impregnated samples and only the irradiated samples showed an acceptable color by the end of day 15.
Aerobics and psychrotrophics counts were significantly reduced by irradiation; while yeast and molds population increased by day 9 and were not completely inactivated with a dose of 1 kGy.
Sensory panelists preferred the treated samples over the controls. The best treatment was the combination of vacuum impregnation with irradiation according to the consumer studies.
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SOCIAL SEEDS AND ENCULTURED CULTURES: MATERIALITY, KNOWLEDGE AND PLACE THROUGH SMALL-SCALE FARMING IN SOUTHERN ILLINOISAdams, Kaitlin Irene 01 May 2015 (has links)
This project explores the relationships between people, environment, and possibility through two of the world's smallest materials: agricultural seeds and mushroom cultures. While often seen as products of nature, seeds and cultures also embody complex social, historical, political and economic realities as they come into contact with human hands. Through fieldwork on small-scale farms in southern Illinois, including farm tours, agricultural trainings and interviews, as well as an analysis of seed descriptions in a popular heirloom seed catalog, this thesis explores how produce seeds and mushroom cultures become things that are known through place and practice. Planting a seed or inoculating a culture is not a simple action, but one imbued with intention, hope and even revolution.
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Psilocybe cyanescens in Germany / Ecology and Taxonomy of an Invasive NeomyceteGießler, Alexander 20 January 2017 (has links)
No description available.
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Effects of raw materials on vermicompost qualitiesA'ali, Rahman, Jafarpour, Mehrdad, Kazemi, Elahe, Pessarakli, Mohammad 11 January 2017 (has links)
Overuse of the chemical compounds and toxic elements leads to problems and transmission of contaminants and pollutants to humans and other living organisms. One of the industries’ byproducts of the agriculture sector is production of various composts from the organic raw materials that the best type of which is so – called Vermicompost. In this study, effects of raw materials on qualitative and quantitative characteristics of Vermicompost are discussed. To do so, sheep manure, pomegranate peels, spent mushroom compost either singly or double, triple or fourfold chopped corn, sugar beet pulp and sawdust were used. This research project was conducted in a completely randomized design experiment with 23 treatments with 3 replications. Results revealed that various bed combinations exert different effects on Vermicompost quality such that, the Vermicomposting process led to a significant decrease in electrical conductivity (EC) and a significant increase in pH in most of the culture (seed) beds. Also, the levels of Nitrogen, Phosphorous and Potassium in most treatments increased following completion of the vermicomposting process. As a result, this process can be introduced as an organic fertilizer with complete nutrients for improving chemical characteristics of agricultural wastes to usable fertilizers.
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Morphological Analysis of Kenyon Cells of the Drosophila Mushroom BodiesVasmer, David 21 December 2016 (has links)
No description available.
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Neuroanatomical and neurochemical correlates of senescence and social role in the ant Pheidole dentataGiraldo, Ysabel Milton 12 March 2016 (has links)
Sociality shapes patterns of senescence, evidenced by the remarkable lifespan plasticity of social insect queens and workers. Ants, exemplars of eusociality, provide diverse systems to explore the sociobiology of senescence by examining how sterile workers partition colony labor over their lifespans, and how neurobiological factors affect transitions among social roles and age-related task performance efficacies. Integrating sociobiology, senescence theory, and neurobiology, I examined the relationship of chronological age and social behavior during the ~140-day lifespan of workers of the ant Pheidole dentata. I critically analyzed programmed senescence in respect to the sociobiology of worker longevity and evaluated how large colony size achieved through selection for extended worker lifespan enhances colony fitness. My study found no support for worker programmed senescence. Further testing senescence theory, I determined if workers declined behaviorally as they aged due to increased apoptotic cell death and changes in synaptic complexes associated with higher-order processing in the brain. Using robust behavioral assays I found aging was not correlated with declines in sensory responsiveness or motor functions associated with foraging, nursing, and prey-capture tasks, or activity level and phototaxis. Old minor workers (95 days) followed pheromone trails for greater distances than 20-day old minors and showed higher activity levels, suggesting improvement in behavioral performance. Neural substrates likely underscoring task performance were maintained with age: synaptic complex density was constant and apoptosis was unchanged with age. Sensory and motor control brain regions did not show age-related increases in neurodegeneration. Worker spatial location predicted social role independent of age: foragers exhibited higher activity levels and more aggressive predatory behavior than nurses. Serotonin and dopamine titers increased from 20 to 120 days but showed no clear correlation with social role. Pharmacological manipulations of brain serotonin had no effect on brood care, predatory response, activity, or phototaxis. Finally, I assessed arborization of a serotonergic neuron hypothesized to underscore task performance to determine how aging across subcastes influences neuronal structure. Major workers showed greater branching complexity than minors and an age-related increase in arbor complexity. P. dentata workers appear to show negligible behavioral and neural senescence throughout their lifespans.
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