19,035 research outputs found

    Evolutionary Physiology: The extent of C4 and CAM photosynthesis in the Genera Anacampseros and Grahamia of the Portulacaceae

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    The Portulacaceae is one of the few terrestrial plant families known to have both C(4) and Crassulacean acid metabolism (CAM) species. There may be multiple origins of the evolution of CAM within the Portulacaceae but the only clear evidence of C(4) photosynthesis is found in members of the genus Portulaca. In the Portulaca, CAM succulent tissue is overlaid with the C(4) tissue in a unique fashion where both pathways are operating simultaneously. Earlier reports have shown that the clade containing the genera Anacampseros and Grahamia may also contain C(4) photosynthetic species similar to the Portulaca, which would indicate multiple origins of C(4) photosynthesis within the family. The aim of the present study was to ascertain the true photosynthetic nature of these genera. An initial survey of the carbon isotope composition of the Anacampseros ranged from -12.6 per thousand to -24.0 per thousand, indicating very little CAM activity in some species, with other values close to the C(4) range. Anacampseros (=Grahamia) australiana which had been previously identified as a C(4) species had a carbon isotope composition value of -24.0 per thousand, which is more indicative of a C(3) species with a slight contribution of CAM activity. Other Anacampseros species with C(4)-like values have been shown to be CAM plants. The initial isotope analysis of the Grahamia species gave values in the range of -27.1 per thousand to -23.6 per thousand, placing the Grahamia species well towards the C(3) photosynthetic range. Further physiological studies indicated increased night-time CO(2) uptake with imposition of water stress, associated with a large diurnal acid fluctuation and a marked increased phosphoenolpyruvate carboxylase activity. This showed that the Grahamia species are actually facultative CAM plants despite their C(3)-like carbon isotope values. The results indicate that the Grahamia and Anacampseros species do not utilize the C(4) photosynthetic pathway. This is the first to identify that the Grahamia species are facultative CAM plants where CAM can be induced by water stress. This work supports earlier physiological work that indicates that this clade containing Anacampseros and Grahamia species comprises predominantly facultative CAM plants. This report suggests there may be only one clade which contains C(4) photosynthetic members with CAM-like characteristics

    Full Recovery From Cocaine-Induced Toxic Leukoencephalopathy: Emphasizing the Role of Neuroinflammation and Brain Edema

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    Toxic leukoencephalopathy (TL) is characterized by white matter disease on magnetic resonance imaging (MRI) and evidence of exposure to a neurotoxic agent. We describe a case of cocaine-induced TL in which extensive white matter disease did not preclude full recovery. A 57-year-old man with substance abuse disorder presented with a 5-day history of strange behavior. On admission, he was alert but had difficulty concentrating, psychomotor retardation, and diffuse hyperreflexia. Brain MRI revealed confluent subcortical white matter hyperintensities with restricted diffusion in some but not in other areas. Electroencephalography (EEG) showed mild diffuse slowing. Blood tests were normal except for mild hyperammonemia. Urine screen was positive for cocaine and benzodiazepine but quantitative analysis was significant only for cocaine. Prednisone 60-mg qd was initiated on day 4, tapered over a 5-day period, and discontinued on day 9. He was discharged after 3 weeks. Cognitive function returned to normal 2 weeks after discharge. Five months later, neurologic exam and EEG were normal and MRI showed near-100% resolution of white matter lesions. TL has been attributed to white matter ischemia/hypoxia resulting in demyelination/axonal injury. The clinical, EEG, and MRI findings and time course of recovery of our patient suggest that cocaine-induced inflammation/edema resulted in TL but not in ischemic/hypoxic injury. While inflammation/edema may have regressed when cocaine was discontinued, we cannot exclude a role for prednisone in protecting the patient from the ischemic/hypoxic sequelae of inflammation/edema. MRI is indispensable for diagnosing TL but EEG may provide additional useful diagnostic and prognostic information

    Factors Affecting Implementation of the California Childhood Obesity Research Demonstration (CA-CORD) Project, 2013.

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    IntroductionEcological approaches to health behavior change require effective engagement from and coordination of activities among diverse community stakeholders. We identified facilitators of and barriers to implementation experienced by project leaders and key stakeholders involved in the Imperial County, California, Childhood Obesity Research Demonstration project, a multilevel, multisector intervention to prevent and control childhood obesity.MethodsA total of 74 semistructured interviews were conducted with project leaders (n = 6) and key stakeholders (n = 68) representing multiple levels of influence in the health care, early care and education, and school sectors. Interviews, informed by the Multilevel Implementation Framework, were conducted in 2013, approximately 12 months after year-one project implementation, and were transcribed, coded, and summarized.ResultsRespondents emphasized the importance of engaging parents and of ensuring support from senior leaders of participating organizations. In schools, obtaining teacher buy-in was described as particularly important, given lower perceived compatibility of the intervention with organizational priorities. From a program planning perspective, key facilitators of implementation in all 3 sectors included taking a participatory approach to the development of program materials, gradually introducing intervention activities, and minimizing staff burden. Barriers to implementation were staff turnover, limited local control over food provided by external vendors or school district policies, and limited availability of supportive resources within the broader community.ConclusionProject leaders and stakeholders in all sectors reported similar facilitators of and barriers to implementation, suggesting the possibility for synergy in intervention planning efforts

    Measuring athlete imagery ability: the Sport Imagery Ability Questionnaire

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    Based on literature identifying movement imagery, observation, and execution to elicit similar areas of neural activity, research has demonstrated movement imagery and observation to successfully prime movement execution. To investigate whether movement and observation could prime ease of imaging from an external visual imagery perspective, an internal visual imagery perspective, and kinaesthetic modality, 36 participants (Mage_{age} = 20.58; SD = 3.11; 18 female, 18 male) completed the Movement Imagery Questionnaire-3 under four modes of delivery (movement prime, external observation prime, internal observation prime, and image-only). Results revealed ease of imaging was significantly greater during the movement and observation prime conditions compared to the image-only condition (p < .05). Specifically when priming external visual imagery and internal visual imagery, observation only facilitated ease of imaging when the perspective was congruent with the imagery perspective. Results support the utilization of movement and observation to facilitate ease of imaging, but highlight the importance of considering visual perspective when using observation

    The Blurred Line between Physical Ageing and Mental Health in Older Adults: Implications for the Measurement of Depression

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    Objectives: Depression in older adults is assessed using measures validated in the general adult population. However, such measures may be inappropriate in the elderly due to the similarities between ageing and the symptoms of depression. This article discusses whether these measures are fit for the purpose and the implications of using inappropriate tools. Methods: A commentary on measuring depression in older adults. Results: Depression symptoms may be mistaken for signs of ageing. Several measures of depression include items that may have a physical cause and thus generate measurement error. Those studies that have assessed the psychometric properties of depression measures in older adults have failed to conduct appropriate assessments of discriminant validity. Discussion: Research is needed to determine whether the conceptual similarity between some symptoms of depression and the effects of ageing translate to factorial similarity. If so, there may be a need for a specific depression measure for older adults that prioritises psychological symptoms

    Managing The Accreditation Goal For A Multi-Campus Business School

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    This qualitative study examines the complex issue of a multi-campus business school charged with the goal of accreditation. A review of the literature is followed with survey insights from 22 business school Deans with multi-campus experience, analyzed using constant comparative analysis to seek solution for three central issues (1) to increase the proportion of full-time faculty; (2) encourage scholarship; and (3) foster multi-campus relations. The key findings suggest the central roles of leadership to motivate all constituents, funding, articulation of expectations, and degree for branch autonomy

    What Can We Learn From the Existing Evidence of the Business Case for Investments in Nursing Care: Importance of Content, Context, and Policy Environment

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    Decisions of health care institutions to invest in nursing care are often guided by mixed and conflicting evidence of effects of the investments on organizational function and sustainability. This paper uses new evidence generated through Interdisciplinary Nursing Quality Research Initiative (INQRI)-funded research and published in peer-reviewed journals, to illustrate where the business case for nursing investments stands and to discuss factors that may limit the existing evidence and its transferability into clinical practice. We conclude that there are 3 limiting factors: (1) the existing business case for nursing investments is likely understated due to the inability of most studies to capture spillover and long-run dynamic effects, thus causing organizations to forfeit potentially viable nursing investments that may improve long-term financial stability; (2) studies rarely devote sufficient attention to describing the content and the organization-specific contextual factors, thus limiting generalizability; and (3) fragmentation of the current health care delivery and payment systems often leads to the financial benefits of investments in nursing care accruing outside of the organization incurring the costs, thus making potentially quality-improving and cost-saving interventions financially unattractive from the organization\u27s perspective. The payment reform, with its emphasis on high-quality affordable patient-centered care, is likely to strengthen the business case for investments in nursing care. Methodologically rigorous approaches that focus on broader societal implications of investments in nursing care, combined with a thorough understanding of potential barriers and facilitators of nursing change, should be an integral part of future research and policy efforts

    Observer- September 20, 1945

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    Publisher William H. McClendon Editor [not available] Address 2017 N. Williams Ave., Portland, OR The Observer, volume 4, number 5.https://pdxscholar.library.pdx.edu/observer/1006/thumbnail.jp
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