152 research outputs found

    Assessment of lake sensitivity to acidic deposition in national parks of the Rocky Mountains”. In:

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    Abstract. The sensitivity of high-elevation lakes to acidic deposition was evaluated in five national parks of the Rocky Mountains based on statistical relations between lake acidneutralizing capacity concentrations and basin characteristics. Acid-neutralizing capacity (ANC) of 151 lakes sampled during synoptic surveys and basin-characteristic information derived from geographic information system (GIS) data sets were used to calibrate the statistical models. The explanatory basin variables that were considered included topographic parameters, bedrock type, and vegetation type. A logistic regression model was developed, and modeling results were cross-validated through lake sampling during fall 2004 at 58 lakes. The model was applied to lake basins greater than 1 ha in area in Glacier National Park (n ¼ 244 lakes), Grand Teton National Park (n ¼ 106 lakes), Great Sand Dunes National Park and Preserve (n ¼ 11 lakes), Rocky Mountain National Park (n ¼ 114 lakes), and Yellowstone National Park (n ¼ 294 lakes). Lakes that had a high probability of having an ANC concentration ,100 leq/L, and therefore sensitive to acidic deposition, are located in basins with elevations .3000 m, with ,30% of the catchment having northeast aspect and with .80% of the catchment bedrock having low buffering capacity. The modeling results indicate that the most sensitive lakes are located in Rocky Mountain National Park and Grand Teton National Park. This technique for evaluating the lake sensitivity to acidic deposition is useful for designing long-term monitoring plans and is potentially transferable to other remote mountain areas of the United States and the world

    Assessment of lake sensitivity to acidic deposition in national parks of the Rocky Mountains”. In:

    Get PDF
    Abstract. The sensitivity of high-elevation lakes to acidic deposition was evaluated in five national parks of the Rocky Mountains based on statistical relations between lake acidneutralizing capacity concentrations and basin characteristics. Acid-neutralizing capacity (ANC) of 151 lakes sampled during synoptic surveys and basin-characteristic information derived from geographic information system (GIS) data sets were used to calibrate the statistical models. The explanatory basin variables that were considered included topographic parameters, bedrock type, and vegetation type. A logistic regression model was developed, and modeling results were cross-validated through lake sampling during fall 2004 at 58 lakes. The model was applied to lake basins greater than 1 ha in area in Glacier National Park (n ¼ 244 lakes), Grand Teton National Park (n ¼ 106 lakes), Great Sand Dunes National Park and Preserve (n ¼ 11 lakes), Rocky Mountain National Park (n ¼ 114 lakes), and Yellowstone National Park (n ¼ 294 lakes). Lakes that had a high probability of having an ANC concentration ,100 leq/L, and therefore sensitive to acidic deposition, are located in basins with elevations .3000 m, with ,30% of the catchment having northeast aspect and with .80% of the catchment bedrock having low buffering capacity. The modeling results indicate that the most sensitive lakes are located in Rocky Mountain National Park and Grand Teton National Park. This technique for evaluating the lake sensitivity to acidic deposition is useful for designing long-term monitoring plans and is potentially transferable to other remote mountain areas of the United States and the world

    Differential glucocorticoid metabolism in patients with persistent versus resolving inflammatory arthritis

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    Introduction: Impairment in the ability of the inflamed synovium to generate cortisol has been proposed to be a factor in the persistence and severity of inflammatory arthritis. In the inflamed synovium, cortisol is generated from cortisone by the 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme. The objective of this study was to determine the role of endogenous glucocorticoid metabolism in the development of persistent inflammatory arthritis. Methods: Urine samples were collected from patients with early arthritis (symptoms ≤12 weeks duration) whose final diagnostic outcomes were established after clinical follow-up and from patients with established rheumatoid arthritis (RA). All patients were free of disease-modifying anti-rheumatic drugs at the time of sample collection. Systemic measures of glucocorticoid metabolism were assessed in the urine samples by gas chromatography/mass spectrometry. Clinical data including CRP and ESR were also collected at baseline. Results: Systemic measures of 11β-HSD1 activity were significantly higher in patients with early arthritis whose disease went on to persist, and also in the subgroup of patients with persistent disease who developed RA, when compared with patients whose synovitis resolved over time. We observed a significant positive correlation between systemic 11β-HSD1 activity and ESR/CRP in patients with established RA but not in any of the early arthritis patients group. Conclusions: The present study demonstrates that patients with a new onset of synovitis whose disease subsequently resolved had significantly lower levels of systemic 11β-HSD1 activity when compared with patients whose synovitis developed into RA or other forms of persistent arthritis. Low absolute levels of 11β-HSD1 activity do not therefore appear to be a major contributor to the development of RA and it is possible that a high total body 11β-HSD1 activity during early arthritis may reduce the probability of disease resolution

    All-trans retinoic acid (ATRA)-induced TFEB expression is required for myeloid differentiation in acute promyelocytic leukemia (APL)

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    © 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd Objective: In acute promyelocytic leukemia (APL), normal retinoid signaling is disrupted by an abnormal PML-RARα fusion oncoprotein, leading to a block in cell differentiation. Therapeutic concentrations of all-trans-retinoic acid (ATRA) can restore retinoid-induced transcription and promote degradation of the PML-RARα protein. Autophagy is a catabolic pathway that utilizes lysosomal machinery to degrade intracellular material and facilitate cellular re-modeling. Recent studies have identified autophagy as an integral component of ATRA-induced myeloid differentiation. Methods: As the molecular communication between retinoid signaling and the autophagy pathway is not defined, we performed RNA sequencing of NB4 APL cells treated with ATRA and examined autophagy-related transcripts. Results: ATRA altered the expression of >80 known autophagy-related transcripts, including the key transcriptional regulator of autophagy and lysosomal biogenesis, TFEB (11.5-fold increase). Induction of TFEB and its transcriptional target, sequestosome 1 (SQSTM1, p62), is reduced in ATRA-resistant NB4R cells compared to NB4 cells. TFEB knockdown in NB4 cells alters the expression of transcriptional targets of TFEB and reduces CD11b transcript levels in response to ATRA. Conclusions: We show for the first time that TFEB plays an important role in ATRA-induced autophagy during myeloid differentiation and that autophagy induction potentiates leukemic cell differentiation (Note: this study includes data obtained from NCT00195156, https://clinicaltrials.gov/show/NCT00195156)

    Realising the Olympic dream: vision, support and challenge

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    The sporting arena is replete with examples and anecdotes of great inspirational coaches that have led teams to success, often in the face of adversity and against seemingly better opponents. The role of the coach in developing and motivating athletes has also been the focus of much research in sport psychology (e.g., Challaduria 1990; Smith & Smoll, 2007). Despite the ease with which one readily accepts that coaches can be inspirational, the sport coaching literature is somewhat devoid of research on inspirational coaches and the effects of such coaches on athletic success. The purpose of the current paper is to theoretically delineate the inspirational effects of coaches in sport. Given the relative paucity of inspiration-related research in sport we draw upon contemporary theories of leadership from organisational and military psychology (e.g., transformational and charismatic leadership theories). We propose a sport-specific model of leadership that centres around the vision, support, and challenge meta-cognitive model developed by Arthur and Hardy in military contexts. The model posits that �great� coaches inspire their athletes by: (a) creating an inspirational vision of the future; (b) providing the necessary support to achieve the vision; and (c) providing the challenge to achieve the vision. The underlying proposition is that the vision provides meaning and direction for followers� effort. That is, the vision serves as the beacon around which all the sweat, pain and sacrifice involved in achieving success at the highest level in sport is directed. At the heart of this model is the notion that athletes can achieve their dreams provided they are inspired to do so; this is because all other things being equal the person who is motivated to practice longer and train harder will ultimately be the best. The current paper will delineate the coach�s role in inspiring the athlete to train harder and longer

    Integrating Values, Purposes, and Visions for Responsible Development

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    This chapter highlights a study showing that knowledge sharing and envisioning processes can have positive effects on human and social capital growth within a network. The chapter begins by arguing that a responsible development perspective can be more proactive approach than a sustainability perspective. Some actors (non-profit, public, and private) have achieved responsible development goals by integrating values, purposes and visions. More specifically, we conducted a study testing a methodology that can guide a process of building a strategic vision within a network with the goal of improving their responsible development orientation. The chosen methodology is “Participatory Action Research”. The implementation of the envisioning process was studied via quantitative/qualitative research tools. The methodology was tested in an official cross-country project funded by the European Commission. The project was selected as a best practice by the same European Union Commission. The study highlights the importance of envisioning processes in building social and human capital at the inter-organizational level and, in particular, in highly complex sectors such as those oriented towards improving social responsibility. In fact, work on the envisioning process itself represents an essential instrument for developing strategic objectives to be shared among actors within networks that intend to promote responsible development and improve their human and social capital. This bottom-up process of envisioning can also facilitate cultural interaction among community members, even in a cross-country context. This relevant “learning-by-interacting” experience, can create a growth process for the human and social capital of entire communities. The creation of social capital also promotes the development of shared knowledge and advances leading to the general understanding of common core objectives and appropriate ways of acting within the social system. The chapter ends with recommendations for future research

    Development of cognitive enhancers based on inhibition of insulin-regulated aminopeptidase

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    The peptides angiotensin IV and LVV-hemorphin 7 were found to enhance memory in a number of memory tasks and reverse the performance deficits in animals with experimentally induced memory loss. These peptides bound specifically to the enzyme insulin-regulated aminopeptidase (IRAP), which is proposed to be the site in the brain that mediates the memory effects of these peptides. However, the mechanism of action is still unknown but may involve inhibition of the aminopeptidase activity of IRAP, since both angiotensin IV and LVV-hemorphin 7 are competitive inhibitors of the enzyme. IRAP also has another functional domain that is thought to regulate the trafficking of the insulin-responsive glucose transporter GLUT4, thereby influencing glucose uptake into cells. Although the exact mechanism by which the peptides enhance memory is yet to be elucidated, IRAP still represents a promising target for the development of a new class of cognitive enhancing agents
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