861 research outputs found

    Benefits of Nitric Oxide Cues to Matrix Synthesis by Healthy and Aneurysmal Human Smooth Muscle Cells Within 3D Cocultures

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    Vascular diseases such as atherosclerosis and aneurysms are characterized by the over-proliferation and migration of aortic smooth muscle cells (SMCs), and degradation of extracellular matrix (ECM) within the vessel wall, leading to compromise in cell-cell and cell-matrix signaling pathways. Recent tissue engineering approaches to regulate SMC over-proliferation and enhance healthy ECM synthesis showed promise, but resulted in low crosslinking efficiency and matrix deposition yields. In this study, the benefits of exogenous nitric oxide cues, delivered from S-Nitrosoglutathione (GSNO), to cell proliferation and matrix deposition by adult human aortic SMCs (HA-SMCs) within 3D biomimetic cultures have been explored. The first experiment utilized a microfluidic platform with two adjacent, permeable 3D culture chambers, to enable paracrine signaling between vascular cell cocultures. Healthy HA-SMCs were cultured in these devices within 3D collagen hydrogels, either alone or in the presence of human aortic endothelial cell (HA-ECs) cocultures, and exogenously supplemented with varying GSNO dosages (0-100 nM) for 21 days. Results showed that EC cocultures stimulated SMC proliferation within GSNO-free cultures. However, with increasing GSNO concentration, HA-SMC proliferation decreased in the presence or absence of EC cocultures, while HA-EC proliferation increased. GSNO (100 nM) significantly enhanced the total protein amount synthesized by HA-SMCs, in the presence or absence of EC cocultures, while lower dosages (1-10 nM) offered marginal benefits. On a per cell basis, multi-fold increases in the synthesis and deposition of elastin, glycosaminoglycans, hyaluronic acid and lysyl oxidase crosslinking enzyme (LOX) were noted at higher GSNO dosages, and coculturing with ECs significantly furthered these trends. The matrix yields of these proteins reached almost 40 - 51 within selective cocultures receiving GSNO. Similar increases in TIMP-1 and MMP-9 levels were noted within cocultures with increasing GSNO do

    Military fictions: Stories about soldiers, 1914-1930

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    Much criticism of the fiction of the Great War has relied on certain assumptions: that Britain's involvement in the War was futile, and that good writing about it must necessarily be ironic; that only fighting soldiers knew War's truth, while civilians were kept ignorant by censorship and propaganda; and that the disillusioned fiction of the late twenties belatedly revealed the 'truth about the War. This thesis asks what the literature looks like if these propositions are not taken for granted. It finds in wartime Britain a 'culture of consent' regulated more by public opinion than by official interference, and argues that reticence need not imply ignorance. The dominant representation of the soldier, as controlled and responsible, did not necessarily lead to endorsement of unthinking patriotism, but is found in texts whose aim is to regulate war enthusiasm. Some unorthodox accounts of soldiers were written and published during wartime; some of the institutions of the literary world hampered writers' expression more than official censorship. During the twenties, representations of War and soldiers were often determined by the time's anxieties, and by a need to understand the War's place in history; the conflict was rarely shown as futile, even in fiction tackling the difficult subject of military executions. Stories about ex-soldiers sometimes presented them as victims, sometimes as a disturbing presence in post-war society. Other ex-soldiers were seen as the answer to society's problems in the years before the General Strike. The war books published at the end of the twenties are more varied than has often been suggested, though many contemporary readers wanted them all to preach a message of wars futility. These and later fictions tell us as much about the times in which they are written as about the War itself. There is more to Great War fiction than, for example, the narrow selection found on current educational syllabuses

    Bridging the gap between current special education practices and models of best practice in addressing the needs of students with emotional disabilities

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    This study serves as an investigation of the current practices of special education teachers when working with children labeled as Emotionally Disabled. This paper explores research that highlights a critical “gap” that has existed between the research and special education fields in the provision of support and intervention services for students with emotional disabilities. Although a significant amount of research exists pertaining to best practices and evidence-based interventions when working with children with emotional disabilities; specific research regarding current practices of special education teachers and to what degree best practices recommendations are being implemented with these students is sparse. The current study is proposed as a means of gaining insight into current practices of special education teachers in order to evaluate if this proposed “gap” continues to exist, and if so, to identify possible reasons for its continued existence. In this study, special education teachers in the state of Virginia were asked to complete a survey specific to their current practices when working with students with emotional disabilities and regarding their personal opinions related to the feasibility, practicality, and applicability of scientifically supported evidence-based recommendations when working with students with emotional disabilities within the academic setting

    Concurrent investigation of global motion and form processing in amblyopia: an equivalent noise approach

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    PURPOSE: Directly comparing the motion and form processing in neurologic disorders has remained difficult due to the limitations in the experimental stimulus. In the current study, motion and form processing in amblyopia was characterized using random dot stimuli in different noise levels to parse out the effect of local and global processing on motion and form perception. METHODS: A total of 17 amblyopes (8 anisometropic and 9 strabismic), and 12 visually normal subjects monocularly estimated the global direction of motion and global orientation in random dot kinematograms (RDK) and Glass patterns (Glass), whose directions/orientations were drawn from normal distributions with a range of means and variances that served as external noise. Direction/orientation discrimination thresholds were measured without noise first then variance threshold was measured at the multiples of the direction/orientation threshold. The direction/orientation and variance thresholds were modelled to estimate internal noise and sampling efficiency parameters. RESULTS: Overall, the thresholds for Glass were higher than RDK for all subjects. The thresholds for both Glass and RDK were higher in the strabismic eyes compared with the fellow and normal eyes. On the other hand, the thresholds for anisometropic amblyopic eyes were similar to the normal eyes. The worse performance of strabismic amblyopes was best explained by relatively low sampling efficiency compared with other groups (P < 0.05). CONCLUSIONS: A deficit in global motion and form perception was only evident in strabismic amblyopia. Contrary to the dorsal stream deficiency hypothesis assumed in other developmental disorders, deficits were present in both motion (dorsal) and form (ventral) processing

    Identifying Knowledge, Skill, and Ability Requirements for 33Sx Officers in Deployed Environments

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    Military operations in the past, present, and future are highly dependent on the timely distribution of accurate information; the only thing really changing is the speed and means of which it is dispersed. As we proceed forward in the information age, technology and the men and women responsible for it will play an ever increasing role in getting the right information in the right place at the right time. As the United States Air Force continues to transform into an ever increasing expeditionary service the knowledge, skills, and abilities of Air Force officers must transform as well to meet the evolving needs of combatant commanders. 33S officers perform garrison duties in many different capacities; current duty position or past experience thus does not guarantee we have acquired the knowledge, skills and abilities necessary to succeed when and where it matters most. Hence, the purpose of this research is to identify core skill sets in the form of knowledge, skills, and abilities, which are most important to Communication and Information (AFSC 33S) Officers to successfully carry out assigned duties in forward operating locations

    The impact of masking of persuasive intent on persuasive message effectiveness

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    The decreased dependency of marketing managers on traditional message forms (i.e., commercials) has increased the use of nontraditional message forms (i.e., product placement) in marketing communication. These newer message forms are unique because their persuasive intent is concealed by the presentation method and, therefore, may be processed differently than the traditional message forms. Consequently, this paper examines three major issues that arise out of the integration of nontraditional message forms into marketing communication, including (1) incorporating nontraditional message forms into the traditional persuasion literature, (2) introducing a new persuasion element (termed masking of persuasive intent) and its role in the persuasion process, and (3) the inclusion of resistance to persuasion as a related outcome when including nontraditional approaches in a persuasion model. Message form (masking of persuasive intent) is proposed to serve as both an antecedent to processing and as a moderator of the persuasion model. Two models are generated based on the extant persuasion literature to test the model. The generalized model tests masking of persuasive intent as an antecedent and the message form-specific models test the moderating effect of message form. Findings confirm that the operation of the traditional persuasion model does not change with the addition of masking of persuasive intent and resistance to persuasion. However, masking of persuasive intent was found to act as an antecedent in the model, influencing processing style. Higher levels of masking of persuasive intent (product placement) involve more affective processing relative to cognitive processing. Product placement is an effective persuasion technique, but it is losing its uniqueness because of its widespread use. Although product placement is not as impactful as predicted, this research demonstrates that masking of persuasive intent does affect processing style, which ultimately impacts attitude change. In conclusion, both the traditional and nontraditional message forms can be used effectively to deliver a persuasive message. Product placement has the same benefits as the commercial, but may capture a larger number of people watching the program than commercials, which people may choose not to watch

    Tenderness of Beef Round Roasted at Two Oven Temperatures in Relation to Cooking Losses, Cooking Time, Power Consumption, and Other Sensory Properties

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    From the Introduction): Abbreviated The present study was designed to compare the tenderness and quality of adjacent top-round roasts cooked at 300oF. and 200oF. oven temperatures

    Classification and Geolocation of Cotton and Palmer Amaranth Using Spectral and Geometric Data

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    The discrimination between cotton and the invasive Palmer amaranth is economically important, as these weeds take resources away from cotton, resulting in diminished crop yield. There has been research into the discrimination between species of plants, including cotton and Palmer amaranth, that focused on the use of aerial imagery and the derived Red, Green, and near-infrared (RGN) spectral data fed into a machine-learning algorithm to classify these plants based on the measurable differences in their spectral characteristics. We believe that this research can be expanded upon by using geometric data derived from aerial imagery to classify cotton and non-cotton plants based on their physical characteristics. This would also allow for accurate geolocation of the classified weeds for later removal. An autonomous drone with a GPS and a RGN camera attached will take a predetermined path to scan a crop field, and the resulting videos will be divided into individual frames. From these frames, both the RGN spectral data and a 3D point cloud can be derived. The RGN data and the geometric data will be fed into a machine learning algorithm for classification between the cotton and non-cotton plants, and then additional processing will be done to geolocate the weeds. With this additional information for classification, it is hoped that the discrimination between cotton and weeds can be more accurate, and the location of the weeds can be more exact
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