132 research outputs found
Sun, Moon, Stars, Rain, Vol. 7 No. 11
Official publication of the Sigma Tau Delta English Honor Society, Alpha Zet Chapter, Stephen F. Austin State University.
Published one a year in the Fall Semester, in cooperation with the English Department of Stephen F. Austin State University.https://scholarworks.sfasu.edu/smsr/1000/thumbnail.jp
Sun, Moon, Stars, Rain, Vol. 7 No. 11
Official publication of the Sigma Tau Delta English Honor Society, Alpha Zet Chapter, Stephen F. Austin State University.
Published one a year in the Fall Semester, in cooperation with the English Department of Stephen F. Austin State University
Reelin Secreted by GABAergic Neurons Regulates Glutamate Receptor Homeostasis
BACKGROUND: Reelin is a large secreted protein of the extracellular matrix that has been proposed to participate to the etiology of schizophrenia. During development, reelin is crucial for the correct cytoarchitecture of laminated brain structures and is produced by a subset of neurons named Cajal-Retzius. After birth, most of these cells degenerate and reelin expression persists in postnatal and adult brain. The phenotype of neurons that bind secreted reelin and whether the continuous secretion of reelin is required for physiological functions at postnatal stages remain unknown. METHODOLOGY/PRINCIPAL FINDINGS: Combining immunocytochemical and pharmacological approaches, we first report that two distinct patterns of reelin expression are present in cultured hippocampal neurons. We show that in hippocampal cultures, reelin is secreted by GABAergic neurons displaying an intense reelin immunoreactivity (IR). We demonstrate that secreted reelin binds to receptors of the lipoprotein family on neurons with a punctate reelin IR. Secondly, using calcium imaging techniques, we examined the physiological consequences of reelin secretion blockade. Blocking protein secretion rapidly and reversibly changes the subunit composition of N-methyl-D-aspartate glutamate receptors (NMDARs) to a predominance of NR2B-containing NMDARs. Addition of recombinant or endogenously secreted reelin rescues the effects of protein secretion blockade and reverts the fraction of NR2B-containing NMDARs to control levels. Therefore, the continuous secretion of reelin is necessary to control the subunit composition of NMDARs in hippocampal neurons. CONCLUSIONS/SIGNIFICANCE: Our data show that the heterogeneity of reelin immunoreactivity correlates with distinct functional populations: neurons synthesizing and secreting reelin and/or neurons binding reelin. Furthermore, we show that continuous reelin secretion is a strict requirement to maintain the composition of NMDARs. We propose that reelin is a trans-neuronal messenger secreted by GABAergic neurons that regulates NMDARs homeostasis in postnatal hippocampus. Defects in reelin secretion could play a major role in the development of neuropsychiatric disorders, particularly those associated with deregulation of NMDARs such as schizophrenia
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Early hominins in north-west Europe: a punctuated long chronology?
In light of changing views regarding the identity and evolutionary positions of Europe’s Lower Palaeolithic hominins, a re-consideration of the hominin occupation of North-West Europe from c. 1 million years ago (mya) to c. 400 thousand years ago (kya) is timely. A change in the scale and character of the overall European Palaeolithic record around c. 800-600 kya has been well documented and argued over since the mid-1990s. Hominin expansion into the European north-west, potentially from southern Europe, Africa or south-western Asia, has been linked to the introduction of a new lithic technology in the form of the biface. We evaluate three potential drivers for this northern range expansion: changing palaeo-climatic conditions, the emergence of an essentially modern human life history, and greater hominin behavioural plasticity. Our evaluation suggests no major changes in these three factors during the c. 800-600 kya period other than enhanced behavioural plasticity suggested by the appearance of the biface. We offer here a model of hominin occupation for north-west Europe termed the ‘punctuated long chronology’ and suggest that the major changes in the European Lower Palaeolithic record that occur at a species wide level may post-date, rather than precede, the Anglian Glaciation (marine isotope stage (MIS) 12)
Scenarios and design: Scoping the dialogue space
This paper examines the intersections between two futures-oriented domains of practice and research: scenario planning and design. Both are practice-led, with uneasy but productive relationships with theorizing. Exploring their relations offers ways to address challenges faced by interdisciplinary management research, which struggles to connect research and practice. The authors describe how they brought the two fields together. We outline how we convened, designed and facilitated the fourth Oxford Futures Forum held in May 2014. This event brought together leading practitioners and researchers in a collective inquiry based on self-organizing, generative and reflexive making and dialogue. How participants engaged, from responding to the invitation to take part, as well as their practical and discursive encounters with one another during the event, threw up similarities and differences between the two fields. We present nine themes that capture the links and spaces between design and scenarios, yet suggest that they are not a straightforward overlap or a simple relationship, but rather a range of interactions between the fields, including feeding in, bridging, tension and repulsion. The paper's contribution is to suggest how scenario planning can engage with design, resulting in new opportunities for research and projects. These modes of engagement provide a framing to explore dialogues between other management disciplines
Competitive Tendering In The Netherlands: Central Planning Or Functional Specifications?
Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne
Information and digital literacies; a review of concepts
A detailed literature reviewing, analysing the multiple and confusing concepts around the ideas of information literacy and digital literacy at the start of the millennium. The article was well-received, and is my most highly-cited work, with over 1100 citations
Physical activity for women with breast cancer after adjuvant therapy
© 2018 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. Background: Women with a diagnosis of breast cancer may experience short- and long-term disease and treatment-related adverse physiological and psychosocial outcomes. These outcomes can negatively impact prognosis, health-related quality of life (HRQoL), and psychosocial and physical function. Physical activity may help to improve prognosis and may alleviate the adverse effects of adjuvant therapy. Objectives: To assess effects of physical activity interventions after adjuvant therapy for women with breast cancer. Search methods: We searched the Cochrane Breast Cancer Group (CBCG) Specialised Registry, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Physiotherapy Evidence Database (PEDro), SPORTDiscus, PsycINFO, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform, on 18 September 2015. We also searched OpenGrey and Healthcare Management Information Consortium databases. Selection criteria: We searched for randomised and quasi-randomised trials comparing physical activity interventions versus control (e.g. usual or standard care, no physical activity, no exercise, attention control, placebo) after adjuvant therapy (i.e. after completion of chemotherapy and/or radiation therapy, but not hormone therapy) in women with breast cancer. Data collection and analysis: Two review authors independently selected studies, assessed risk of bias, and extracted data. We contacted trial authors to ask for additional information when needed. We calculated an overall effect size with 95% confidence intervals (CIs) for each outcome and used GRADE to assess the quality of evidence for the most important outcomes. Main results: We included 63 trials that randomised 5761 women to a physical activity intervention (n = 3239) or to a control (n = 2524). The duration of interventions ranged from 4 to 24 months, with most lasting 8 or 12 weeks (37 studies). Twenty-eight studies included aerobic exercise only, 21 involved aerobic exercise and resistance training, and seven used resistance training only. Thirty studies described the comparison group as usual or standard care, no intervention, or control. One-fifth of studies reported at least 20% intervention attrition and the average physical activity adherence was approximately 77%. No data were available on effects of physical activity on breast cancer-related and all-cause mortality, or on breast cancer recurrence. Analysis of immediately postintervention follow-up values and change from baseline to end of intervention scores revealed that physical activity interventions resulted in significant small-to-moderate improvements in HRQoL (standardised mean difference (SMD) 0.39, 95% CI 0.21 to 0.57, 22 studies, 1996 women; SMD 0.78, 95% CI 0.39 to 1.17, 14 studies, 1459 women, respectively; low-quality evidence), emotional function (SMD 0.21, 95% CI 0.10 to 0.32, 26 studies, 2102 women, moderate-quality evidence; SMD 0.31, 95% CI 0.09 to 0.53, 15 studies, 1579 women, respectively; low-quality evidence), perceived physical function (SMD 0.33, 95% CI 0.18 to 0.49, 25 studies, 2129 women; SMD 0.60, 95% CI 0.23 to 0.97, 13 studies, 1433 women, respectively; moderate-quality evidence), anxiety (SMD -0.57, 95% CI -0.95 to -0.19, 7 studies, 326 women; SMD -0.37, 95% CI -0.63 to -0.12, 4 studies, 235 women, respectively; low-quality evidence), and cardiorespiratory fitness (SMD 0.44, 95% CI 0.30 to 0.58, 23 studies, 1265 women, moderate-quality evidence; SMD 0.83, 95% CI 0.40 to 1.27, 9 studies, 863 women, respectively; very low-quality evidence). Investigators reported few minor adverse events. Small improvements in physical activity interventions were sustained for three months or longer postintervention in fatigue (SMD -0.43, 95% CI -0.60 to -0.26; SMD -0.47, 95% CI -0.84 to -0.11, respectively), cardiorespiratory fitness (SMD 0.36, 95% CI 0.03 to 0.69; SMD 0.42, 95% CI 0.05 to 0.79, respectively), and self-reported physical activity (SMD 0.44, 95% CI 0.17 to 0.72; SMD 0.51, 95% CI 0.08 to 0.93, respectively) for both follow-up values and change from baseline scores. However, evidence of heterogeneity across trials was due to variation in intervention components (i.e. mode, frequency, intensity, duration of intervention and sessions) and measures used to assess outcomes. All trials reviewed were at high risk of performance bias, and most were also at high risk of detection, attrition, and selection bias. In light of the aforementioned issues, we determined that the evidence was of very low, low, or moderate quality. Authors' conclusions: No conclusions regarding breast cancer-related and all-cause mortality or breast cancer recurrence were possible. However, physical activity interventions may have small-to-moderate beneficial effects on HRQoL, and on emotional or perceived physical and social function, anxiety, cardiorespiratory fitness, and self-reported and objectively measured physical activity. The positive results reported in the current review must be interpreted cautiously owing to very low-to-moderate quality of evidence, heterogeneity of interventions and outcome measures, imprecision of some estimates, and risk of bias in many trials. Future studies with low risk of bias are required to determine the optimal combination of physical activity modes, frequencies, intensities, and durations needed to improve specific outcomes among women who have undergone adjuvant therapy.Published versio
Thesauri and Facets and Tags, Oh My! A Look at Three Decades in Subject Analysis
The field of subject analysis enjoyed a flurry of interest in the 1970s,
and has recently become a focus of attention again. The scholarly
community doing work in this area has become more diffuse, and
has grown to include new groups, such as information architects.
Changes in information services and information seeking have led
to reexamination of the nature and role of subject analysis tools
and practices. This selective review looks at thesauri, guided navigation,
and folksonomy as three activity areas in which subject analysis
researchers have been attempting to address rapidly changing new
environments.published or submitted for publicatio
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