493 resultados para Louisiana


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The mechanisms of helicopter flight create a unique, high-vibration environment which can play havoc with the accurate operation of on-board sensors. Vibration isolation of electronic sensors from structural borne oscillations is paramount to their reliable and accurate use. Effective isolation is achieved by realising a trade-off between the properties of the suspended instrument package, and the isolation mechanism. This is made more difficult as the weight and size of the sensors and computing hardware decreases with advances in technology. This paper presents a history of the design, challenges, constraints and construction of an integrated isolated vision and sensor platform and landing gear for the CSIRO autonomous X-Cell helicopter. The results of isolation performance and in-flight tests of the platform in autonomous flight are presented.

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In this paper, we outline the sensing system used for the visual pose control of our experimental car-like vehicle, the autonomous tractor. The sensing system consists of a magnetic compass, an omnidirectional camera and a low-resolution odometry system. In this work, information from these sensors is fused using complementary filters. Complementary filters provide a means of fusing information from sensors with different characteristics in order to produce a more reliable estimate of the desired variable. Here, the range and bearing of landmarks observed by the vision system are fused with odometry information and a vehicle model, providing a more reliable estimate of these states. We also present a method of combining a compass sensor with odometry and a vehicle model to improve the heading estimate.

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This paper presentation addresses design-based research that became a catalyst for social change among a disadvantaged school community. The aim of the longitudinal research was to protoype an evidence-based model for whole school digital and print literacy pedagogy renewal among students from low socioeconomic, Indigenous, and migrant backgrounds. Applying Anthony Gidden’s principle of the “duality of structure”, the paper presentation interprets how the collective agency of researchers and the school community began to transform the structural properties of the institution in a two-way dynamism, so that the structural properties of the school were not outside of individual action, but were implicated in its reproduction and transformation.

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This study examines the occurrence of misappropriation-type fraud within Australian listed firms and the relation between the incidence of this type of fraud and a firm's governance strength. We measure governance strength using factors relating to traditional corporate governance, such as board composition, CEO duality, and audit committee composition, as well as factors relating to information technology governance. In our study, we use actual dollar amount of fraud reported by listed companies responding to the 2004 KPMG Fraud Survey as one of three different misappropriation measures and publicly available firm-specific data to measure the other variables in the model. Our study found that where the chief executive officer (CEO) also holds the position of chairperson of the board of directors, the likelihood of fraud increases. We also find that the greater the number of independent directors on the audit committee, the lower the level of fraud. Taken together, these results are particularly encouraging as they provide support for regulatory bodies such as the Australian Stock Exchange (ASX) and the Australian Securities and Investment Commission (ASIC), which place considerable emphasis on the importance of establishing good corporate governance practices. The study provides empirical evidence that employing good corporate governance reduces the risk of the misappropriation of assets.

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Robotics is a valuable tool for engaging students in the hands-on application of science, technology, engineering, and mathematics (STEM) concepts. Robotics competitions such as FIRST LEGO League (FLL) can increase students’ interest in the STEM subjects and can foster their problem solving and teamwork skills. This paper reports on a study investigating students’ perceptions on the influence of participating in a FLL competition on their learning. The students completed questionnaires regarding their perceptions of their learning during the FLL challenge and were also interviewed to gain a deeper understanding of their questionnaire responses. The results show that the students were engaged with the FLL challenge and held positive views regarding their experience. The results also suggest that students involved with the FLL challenge improved their learning about real-world applications, problem solving, engagement, communication, and the application of the technology/engineering cycle.

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Legacies of the Global Financial Crisis and major domestic corporate collapses – such as HIH Insurance Pty Ltd and One.Tel Ltd (telecommunications) – have significantly changed Australia‟s financial regulatory landscape. Legal requirements for auditors have attracted particular attention as have practice standards more broadly around disclosure and conflict of interest. Conversely, although successful detection and prosecution of breaches may rest in significant part on forensic accounting activities, Australia‟s practitioners in this field have no minimum training or qualifications standards other than the baseline requirements mandated by the country‟s three professional accounting bodies. For those unaffiliated with these organizations, no professional oversight exists. In Australia, growth in the forensic accounting industry has been in direct response to public demand for expertise in a broad range of fraud, forensic and business analytics areas in order to improve the corporate governance practices of Australian organizations. During the 1990s, Australian forensic accounting firms expanded and diversified into a number of different areas going well beyond just the examination of financial documents and involvement in financial litigation disputes. “Big 4” accounting firms such as PriceWaterhouseCoopers, KPMG, Deloitte and Ernst and Young formed independent forensic accounting or forensic services units; a number of mid-tier and „boutique‟ forensic accounting firms similarly expanded into forensic investigative, analytical and advisory services. By 2008, 800 forensic accountants were registered with the country‟s largest specialist forensic accounting group, the Forensic Accounting Special Interest Group (FASIG) of the ICAA1. Currently, obtaining more precise figures on numbers of forensic accounting practitioners is problematic: professional accounting bodies either do not keep a register or have ceased registering their forensic accounting members; lack of formal recognition, admission or certification processes complicate identification of candidates; and diversity of the skills sets the industry requires has meant the influx of non-accounting based specialists.

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Coastal subsidence causes sea-level rise, shoreline erosion and wetland loss, which poses a threat to coastal populations. This is especially evident in the Mississippi Delta in the southern United States, which was devastated by Hurricane Katrina in 2005. The loss of protective wetlands is considered a critical factor in the extensive flood damage. The causes of subsidence in coastal Louisiana, attributed to factors as diverse as shallow compaction and deep crustal processes, remain controversial. Current estimates of subsidence rates vary by several orders of magnitude. Here, we use a series of radiocarbon-dated sediment cores from the Mississippi Delta to analyse late Holocene deposits and assess compaction rates. We find that millennial-scale compaction rates primarily associated with peat can reach 5mm per year, values that exceed recent model predictions. Locally and on timescales of decades to centuries, rates are likely to be 10 mm or more per year. We conclude that compaction of Holocene strata contributes significantly to the exceptionally high rates of relative sea-level rise and coastal wetland loss in the Mississippi Delta, and is likely to cause subsidence in other organic-rich and often densely populated coastal plains.

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The lateral amygdala (LA) receives information from auditory and visual sensory modalities, and uses this information to encode lasting memories that predict threat. One unresolved question about the amygdala is how multiple memories, derived from different sensory modalities, are organized at the level of neuronal ensembles. We previously showed that fear conditioning using an auditory conditioned stimulus (CS) was spatially allocated to a stable topography of neurons within the dorsolateral amygdala (LAd) (Bergstrom et al, 2011). Here, we asked how fear conditioning using a visual CS is topographically organized within the amygdala. To induce a lasting fear memory trace we paired either an auditory (2 khz, 55 dB, 20 s) or visual (1 Hz, 0.5 s on/0.5 s off, 35 lux, 20 s) CS with a mild foot shock unconditioned stimulus (0.6 mA, 0.5 s). To detect learning-induced plasticity in amygdala neurons, we used immunohistochemistry with an antibody for phosphorylated mitogen-activated protein kinase (pMAPK). Using a principal components analysis-based approach to extract and visualize spatial patterns, we uncovered two unique spatial patterns of activated neurons in the LA that were associated with auditory and visual fear conditioning. The first spatial pattern was specific to auditory cued fear conditioning and consisted of activated neurons topographically organized throughout the LAd and ventrolateral nuclei (LAvl) of the LA. The second spatial pattern overlapped for auditory and visual fear conditioning and was comprised of activated neurons located mainly within the LAvl. Overall, the density of pMAPK labeled cells throughout the LA was greatest in the auditory CS group, even though freezing in response to the visual and auditory CS was equivalent. There were no differences detected in the number of pMAPK activated neurons within the basal amygdala nuclei. Together, these results provide the first basic knowledge about the organizational structure of two different fear engrams within the amygdala and suggest they are dissociable at the level of neuronal ensembles within the LA

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Post traumatic stress disorder (PTSD) is a serious medical condition effecting both military and civilian populations. While its etiology remains poorly understood it is characterized by high and prolonged levels of fear responding. One biological unknown is whether individuals expressing high or low conditioned fear memory encode the memory differently and if that difference underlies fear response. In this study we examined cellular mechanisms that underlie high and low conditioned fear behavior by using an advanced intercrossed mouse line (B6D2F1) selected for high and low Pavlovian fear response. A known requirement for consolidation of fear memory, phosphorylated mitogen activated protein kinase (p44/42 (ERK) MAPK (pMAPK)) in the lateral amygdala (LA) is a reliable marker of fear learning-related plasticity. In this study, we asked whether high and low conditioned fear behavior is associated with differential pMAPK expression in the LA and if so, is it due to an increase in neurons expressing pMAPK or increased pMAPK per neuron. To examine this, we quantified pMAPK-expressing neurons in the LA at baseline and following Pavlovian fear conditioning. Results indicate that high fear phenotype mice have more pMAPK-expressing neurons in the LA. This finding suggests that increased endogenous plasticity in the LA may be a component of higher conditioned fear responses and begins to explain at the cellular level how different fear responders encode fear memories. Understanding how high and low fear responders encode fear memory will help identify novel ways in which fear-related illness risk can be better predicted and treated.

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Biological factors underlying individual variability in fearfulness and anxiety have important implications for stress-related psychiatric illness including PTSD and major depression. Using an advanced intercross line (AIL) derived from C57BL/6 and DBA/2J mouse strains and behavioral selection over 3 generations, we established two lines exhibiting High or Low fear behavior after fear conditioning. Across the selection generations, the two lines showed clear differences in training and tests for contextual and conditioned fear. Before fear conditioning training, there were no differences between lines in baseline freezing to a novel context. However, after fear conditioning High line mice demonstrated pronounced freezing in a new context suggestive of poor context discrimination. Fear generalization was not restricted to contextual fear. High fear mice froze to a novel acoustic stimulus while freezing in the Low line did not increase over baseline. Enhanced fear learning and generalization are consistent with transgenic and pharmacological disruption of the hypothalamic-pituitary-adrenal axis (HPA-axis) (Brinks, 2009, Thompson, 2004, Kaouane, 2012). To determine whether there were differences in HPA-axis regulation between the lines, morning urine samples were collected to measure basal corticosterone. Levels of secreted corticosterone in the circadian trough were analyzed by corticosterone ELISA. High fear mice were found to have higher basal corticosterone levels than low line animals. Examination of hormonal stress response components by qPCR revealed increased expression of CRH mRNA and decreased mRNA for MR and CRHR1 in hypothalamus of high fear mice. These alterations may contribute to both the behavioral phenotype and higher basal corticosterone in High fear mice. To determine basal brain activity in vivo in High and Low fear mice we used manganese-enhanced magnetic resonance imaging (MEMRI). Analysis revealed a pattern of basal brain activity made up of amygdala, cortical and hippocampal circuits that was elevated in the High line. Ongoing studies also seek to determine the relative balance of excitatory and inhibitory tone in the amygdala and hippocampus and the neuronal structure of its neurons. While these heterogeneous lines are selected on fear memory expression, HPA-axis alterations and differences in hippocampal activity segregate with the behavioral phenotypes. These differences are detectable in a basal state strongly suggesting these are biological traits underlying the behavioral phenotype (Johnson et al, 2011).

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Chronic difficulties arising from mild brain injury (TBI) are difficult to predict because the processes underlying changes after TBI are poorly understood. In mild brain injury the extent of neuropsychiatric and cognitive symptoms correspond poorly to overt tissue loss (Barth 1983; Liu 2010). Cellular, immune and hormonal cascades occurring after injury and continuing during the healing process may impact uninjured brain regions sensitive to the effects of physiological and emotional stress, which receive projections from the injury site. Changes in these most basic properties due to injury or disease have profound implications for virtually every aspect of brain function through disruption of neurotransmitter, neuroendocrine and metabolic systems. In order to screen for changes in transmitter and metabolic activity, in this study we developed Single voxel proton Magnetic Resonance Spectroscopy (1H-MRS) for use in both injured and control animals. We first evaluated if 1H-MRS could be used to evaluate in vivo, alterations in brain metabolism and catabolism of the prefrontal cortex, amygdala and ventral hippocampus in both control and injured animals after controlled cortical impact injury to the rat prefrontal cortex. We found that metabolite measurements for Myo-Inositol, Choline, creatine, Glutamate+Glutamine, and N-acetyl-acetate are attainable in deep brain structures in vivo in injured and controls rats. We next seek to evaluate longitudinally, in vivo, alterations in brain metabolism and catabolism of the prefrontal cortex, amygdala and ventral hippocampus during the first month after controlled cortical impact injury to the rat prefrontal cortex. These ongoing studies will provide data on the changes in transmitters and metabolites over time in injured and non-injured subjects. These studies address some of the fundamental questions about how mild brain injury has such diverse effects on overall brain health and function.

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The collection consists of 25 letters written by Benjamin between 1838 and 1881 on a variety of subjects, four Confederate notes and two bonds bearing his picture, miscellaneous items about Benjamin (1893-1942), nine issues of the Congressional globe with speeches by Benjamin, as well as separate copies of his printed speeches, and a photostatic copy of the "Diary of Events" (400 pp.) kept by Benjamin, the original of which is in the Library of Congress (1862-1864).

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The papers consist of correspondence and reports of Cecelia Razovsky (married name: Davidson), noted social worker specializing in immigration and resettlement of refugees. The collection includes information about her work with the National Council of Jewish Women in the 1920's, and with the National Refugee Service (and predecessor organizations) in the 1930's. Information is included about her work as a Resettlement Supervisor in the post-World War II DP camps in Europe, and as a field worker in the southwestern U.S. for the United Service for New Americans in 1950. The collection contains reports and correspondence from her trips to South America, primarily Brazil: to explore possibilities of refugee settlement in 1937 and 1946; as a representative for United HIAS Service to aid in settling Egyptian and Hungarian refugees in 1957-58; and as a pleasure trip and evaluation of the changes in the Jewish community of the country in 1963. Also included in the collection are many of Razovsky's articles, plays, and pamphlets.

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Glaucoma is the second leading cause of blindness worldwide. Often, the optic nerve head (ONH) glaucomatous damage and ONH changes occur prior to visual field loss and are observable in vivo. Thus, digital image analysis is a promising choice for detecting the onset and/or progression of glaucoma. In this paper, we present a new framework for detecting glaucomatous changes in the ONH of an eye using the method of proper orthogonal decomposition (POD). A baseline topograph subspace was constructed for each eye to describe the structure of the ONH of the eye at a reference/baseline condition using POD. Any glaucomatous changes in the ONH of the eye present during a follow-up exam were estimated by comparing the follow-up ONH topography with its baseline topograph subspace representation. Image correspondence measures of L-1-norm and L-2-norm, correlation, and image Euclidean distance (IMED) were used to quantify the ONH changes. An ONH topographic library built from the Louisiana State University Experimental Glaucoma study was used to evaluate the performance of the proposed method. The area under the receiver operating characteristic curves (AUCs) was used to compare the diagnostic performance of the POD-induced parameters with the parameters of the topographic change analysis (TCA) method. The IMED and L-2-norm parameters in the POD framework provided the highest AUC of 0.94 at 10 degrees. field of imaging and 0.91 at 15 degrees. field of imaging compared to the TCA parameters with an AUC of 0.86 and 0.88, respectively. The proposed POD framework captures the instrument measurement variability and inherent structure variability and shows promise for improving our ability to detect glaucomatous change over time in glaucoma management.

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Contains Deed of Trust, By-Laws, Annual Reports, Corporation Minutes (1909, 1913-1919, 1923-1924, 1926-1933), Minutes of the Board of Trustees (1893, 1899, 1907, 1910, 1915-1916, 1918, 1923, 1926-1927, 1930-1933), and the minutes, correspondence, and reports of the various national and local committees. Financial materials include income and expenditure records (1891-1933), audits (1919-1923, 1926-1928), the records of agricultural loans and mortgages, bond and real estate holdings, and bequests. Includes also correspondence and other materials regarding the establishment of the Fund, correspondence of and other papers concerning the Baron and Baroness de Hirsch, and several histories of the Fund. Included in the wide range of activities are material on the work of the Agriculture Bureau and the Jewish Agriculture Society, Housing, English Classes, Immigration (including monthly reports for several ports of entry 1885-1916) and Immigrant Aid, German Refugee Aid in the early years of the Holocaust, Kings Park, N.Y. Test Farm, the Laundry Project, Peekskill Farm, Public Baths, Student Loans, the Baron de Hirsch Trade School, and the Woodbine Colony and Baron De Hirsch Agricultural & Industrial School. Contains also materials on the Colonization attempts made in Colorado, Connecticut, Florida, Louisiana, Michigan, Minnesota, North Dakota, New Jersey, New York, Pennsylvania, South Dakota, Galveston, Texas, The Southwest, Washington, Canada, and Mexico.