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Clark’s nutcrackers’ (Nucifraga columbiana) ability to discriminate knowledge states of human experimenters during an object-choice taskClary, Dawson 26 April 2012 (has links)
The present thesis examined whether the corvid, Clark’s nutcracker, is able to discriminate knowledge states between human experimenters based upon gestural cues using an object-choice task. To do so, the knowledge state of two experimenters was manipulated – one experimenter was informed, and the other uninformed, as to the location of a hidden food reward. To find the reward, the birds had to use the gesture of the informed experimenter and refrain from using the unreliable gesture of the uninformed experimenter. The nutcrackers responded to the gesture of the informed experimenter at above chance levels when simultaneously presented with the uninformed experimenter’s gesture. When the uninformed experimenter’s gesture was presented alone, the birds continued to follow the gesture. These results suggest the birds learned the gesture was meaningful, perhaps by associative learning, yet when this mechanism was not reliable the nutcrackers based their choices on the knowledge states of the experimenters.
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Clark’s nutcrackers’ (Nucifraga columbiana) ability to discriminate knowledge states of human experimenters during an object-choice taskClary, Dawson 26 April 2012 (has links)
The present thesis examined whether the corvid, Clark’s nutcracker, is able to discriminate knowledge states between human experimenters based upon gestural cues using an object-choice task. To do so, the knowledge state of two experimenters was manipulated – one experimenter was informed, and the other uninformed, as to the location of a hidden food reward. To find the reward, the birds had to use the gesture of the informed experimenter and refrain from using the unreliable gesture of the uninformed experimenter. The nutcrackers responded to the gesture of the informed experimenter at above chance levels when simultaneously presented with the uninformed experimenter’s gesture. When the uninformed experimenter’s gesture was presented alone, the birds continued to follow the gesture. These results suggest the birds learned the gesture was meaningful, perhaps by associative learning, yet when this mechanism was not reliable the nutcrackers based their choices on the knowledge states of the experimenters.
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Možnosti systému Sinumerik 840D při programování louskáčku na ořechy / Sinumerik 840D tools for programming of nutcrackersKundela, Miroslav January 2014 (has links)
This thesis is engaged chip machining using the system Sinumerik 840D-ShopTurn. The first part of the thesis is engaged the incorporation of the control system Sinumerik 840D - ShopTurn among other control systems. The thesis also deals with the basic methods of NC programming with an emphasis on workshop-oriented programming. The practical part includes design and preparation of technical documentation for the selected part (nutcracker), including creating a CNC program using workshoporiented environment - Sinumerik 840D ShopTurn. The program was validated using a graphical simulation software SinuTrain 7.5 and also directly at the machine SP 280SY. At the conclusion was created techno - economic evaluation of the proposed technology.
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Absence of Infrarenal inferior vena cava Leading to Deep Venous Thrombosis and Incidental Finding of Nutcracker SyndromeHussain, Raza, Mansurov, Alay, Chakraborty, Kanishka, Vasileva, Alisa 24 April 2020 (has links)
Introduction: Inferior vena cava (IVC) malformations are extremely rare. Their impact with additional risk factors has not been well studied. Here, we present a case of a young female with absent IVC. She presented with an extensive left lower extremity (LLE) deep venous thrombosis (DVT) after starting oral contraceptives.
Case: A 21-year-old female with no past medical history presented with progressively worsening back pain and LLE edema. Her only medication was combined oral contraceptive (OCP) which was started 4 months ago. Physical exam was significant for blue discoloration of her LLE extending from foot to thigh. The ultrasound showed multiple thrombi within the left common and deep femoral veins, left popliteal vein and left peroneal vein. The abdominal computerized tomography revealed the absence of an infrarenal IVC with collateral azygous, hemiazygous and prominent left gonadal veins. Occlusion by the thrombi extended from the left femoral vein to the left iliac vein. Some extension was noted into the right common iliac vein. She was treated with a catheter directed tissue plasminogen activator (tPA) infusion into the left iliac vein followed by continuous heparin infusion. Hypercoagulable testing was negative. While on heparin, she developed asymptomatic gross hematuria. CT urogram showed a significant dilation of the left gonadal vein, a large vein along the left psoas muscle draining into the left renal vein, and a mild enlargement of right gonadal vein. The urine analysis was negative for bacterial infection; but it contained a numerous amount of red blood cells and protein. Once the hematuria had resolved, she was discharged on apixaban. Her OCP was discontinued.
Discussion: There have been several case reports describing IVC abnormalities associated with DVT. In our case, DVT was likely provoked by usage of OCP. Current guidelines would require provoked DVTs to be treat for at least 3-12 months with anticoagulation therapy. Case reports of IVC malformations illustrated that these patients are at high risk for DVT at baseline. Hence the underlying abnormality still poses a lifetime risk. Also, with abnormal venous vasculature, gross hematuria, proteinuria and the lack of other causes, we suspect underlying Nutcracker syndrome (NS). Her pelvic abdominal pain can also be attributed to pelvic congestion syndrome, which is commonly associated with NS.
Conclusion: There are several questions that arise from this case including: selecting a type of contraceptive method; safety of direct thrombin inhibitors in patients with NS; indefinite direct thrombin inhibitors in young patients. Unfortunately, due to the rarity of this condition, no set guidelines are available on how to manage these individuals.
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Clark's Nutcracker Seed Harvest Patterns in Glacier National Park and a Novel Method for Monitoring Whitebark Pine ConesMaier, Monika E. 01 May 2012 (has links)
Clark's Nutcracker (Nucifraga columbiana) is the primary seed disperser of whitebark pine (Pinus albicaulis), which is in decline throughout its range. There is concern that a decline in whitebark pine will lead to a subsequent decline in local populations of Clark's Nutcracker. Because natural regeneration depends on the presence of Clark's Nutcracker, the process of harvesting whitebark pine seeds needs to be fully understood. In addition, resource managers need a cost-effective method for monitoring nutcracker occurrence in whitebark pine stands during the seed harvest season. I visited eleven study sites in Glacier National Park, Montana, where I searched for Clark's Nutcracker and surveyed whitebark pine cones for seed harvesting scars, the presence of which indicated that nutcrackers harvested seeds. I documented cone use patterns of Clark's Nutcracker and the major cone predator, red squirrel (Tamiasciurus hudsonicus), at five sites. To identify factors that influence cone use, I ran a correlation analysis with nutcracker and red squirrel seed harvesting variables with physical, compositional, and whitebark pine-related factors. I found that nutcrackers harvested seed at every site that had cones available. Nutcrackers harvested seed from a greater proportion of whitebark pine cones in stands where they started intensively harvesting seeds earlier. Nutcrackers began intensively harvesting seeds earlier in stands with higher relative dominance of whitebark pine. Red squirrels depleted the cone source more rapidly in stands with greater whitebark pine mortality, and at one site depleted the cone source completely before nutcrackers began intensively harvesting seeds from that site. The results of this study suggest that Clark's Nutcracker will continue to harvest seeds even as whitebark pine declines, but the decline in whitebark pine may lead to decreased seed dispersal due to greater pre-dispersal cone predation by red squirrels. Finally, I evaluated direct and indirect monitoring methods to identify a cost-effective method to accurately monitor Clark's Nutcracker occurrence in whitebark pine stands during the seed harvest season. I found that surveying scars made by seed-harvesting nutcrackers on whitebark pine cones was the most accurate and economical method of monitoring Clark's Nutcracker occurrence in an area with a low population of Clark's Nutcracker.
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The social cognitive abilities of the Clark’s nutcracker: from self to otherClary, Dawson 13 September 2016 (has links)
This dissertation explored the social cognitive abilities of the Clark’s nutcracker (Nucifraga columbiana), a relatively non-social, food-caching corvid. Corvids are a family of large-brained birds, which are capable of remarkable cognitive feats (e.g., future planning, tool use). These cognitive abilities have been revealed predominantly by testing social species, supporting popular theories that living in social groups drove the evolution of complex cognition. However, few studies have investigated the social cognitive abilities of corvid species that do not live in large groups. Here, I developed novel procedures using the food-caching behaviour of Clark’s nutcrackers as a tool to explore two cognitive abilities predicted to be limited to social species: mirror self-recognition (Chapter 2) and cooperation (Chapter 4). In Chapter 2, birds cached food when alone, with a conspecific present, and with a regular or blurry mirror. The nutcrackers suppressed caching with a regular mirror (as done with a conspecific), but not with the blurry mirror. When integrated with the traditional ‘mark test’, the birds also showed evidence of self-recognition with the blurry mirror by attempting to remove a coloured mark placed on their body with the blurry mirror, but not with an opaque barrier. In Chapter 3, I discuss the importance of self-recognition as a precursor for complex and flexible social cognitive abilities such as cooperation. To investigate cooperation, in Chapter 4 the birds experienced having their caches exchanged with another bird over multiple trials. This procedure assessed whether the normal response of cache suppression with a conspecific could be over-ridden if the experimental contingencies made cache sharing beneficial. The nutcrackers continued to cache in this context, and male birds increased caching when cooperation from the conspecific was exaggerated artificially by the experimenter. Combined, the results indicate the non- social Clark’s nutcracker is capable of mirror self-recognition, and the ability to distinguish one’s ‘self’ from others may facilitate flexible caching decisions, contrary to the predictions of the social living hypotheses. The findings indicate social living alone does not strongly predict complex cognitive abilities and, instead, that multiple evolutionary paths exist for the development of complex cognition. / October 2016
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Belief And Christmas: Performing Belief And The Theory And Practice Of Christmas PerformanceNicely, Brenna 01 January 2013 (has links)
In the United States, Christmastime has become a time of tension between the holy ideals of family togetherness, childhood innocence, and goodwill towards men and commercial idolatry. Christ and Santa Claus are pitted against each other in the war on Christmas between religion and secularism instead of feasting together on ham and figgy pudding in the traditional fashion. While many would agree that the everyday realities of the Christmas season do not often live up to the ideals imposed upon the holiday, few are able to tell why this is so or even trace the roots of their discontent. In an exploration of the unique anomaly of the hierosecular American Christmas, I propose that the unique systems of Christmas belief extend beyond the usual boundaries of sacred and secular to create a complex web of different beliefs that are performed together to create the unique feeling of Christmas. From a performance theory perspective, I use performance as both traditionally theatrical and as a paradigm for understanding and expressing belief in an effort to explore the essential but elusively defined cultural signifiers of the American Christmas. Through a series of case studies focusing on various traditions of Christmas performance, I apply the performance theories of Diana Taylor, Patrice Pavis, Victor Turner and others to such Christmas staples as Charles Dickens’ A Christmas Carol and Tchaikovsky’s The Nutcracker. In doing so, I propose different points for viewing Christmas and introducing new points of inquiry for questioning the meaning of Christmas, belief, and performance
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Skenet Bedrar : En ekokritisk studie av förvandlingstematiken i Skönheten och Odjuret och Nötknäpparen och Råttkungen / Not What it Seems : An Ecocritical Study of the Transformations in Beauty and the Beast and Nutcracker and the Mouse KingTiger, Louise January 2020 (has links)
The following essay investigates the artificial magic environment in two fairy tales with similar tropes and themes, to find out if the magic is necessary for the growth of the characters. The ecocritical movement constitutes the essay’s theoretical background in order to shine a light on the physical nature that has been slightly neglected when it comes to discerning the inner nature of the heroines in these stories. By employing theoretical concepts from animal studies, the essay also examines the relationship between animals and humans for the purpose of including the portrayal of animals in an expanded view on nature. The major conclusion of the essay is that magic can both help and hinder the protagonist’s journey to maturity. Furthermore, these fairy tales portray different methods of downgrading animals, but they also challenge an anthropocentric view of the world.
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