249 research outputs found

    Reshaping Academic Practice and Relationships within the Department Of Plant Sciences

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    At the University of Cambridge, a research and development project concerned with teaching and learning in small-group tutorials has been initiated in Department of Plant Sciences. Known as the Plant Sciences Pedagogy Project, it is part of the Teaching for Learning Network (TfLN), which includes members of the Centre for Applied Research into Educational Technologies (CARET), the Department of Engineering and the Faculty of Classics. Provision of small-group tutorials plays a key role in teaching support for students at the University of Cambridge. However, variation in student experience of tutorial quality was raised as a point of concern in a recent student survey (Cambridge University Students’ Union, 2004). Our research therefore focussed on analysis of the tutorial environment with the aim of finding out how best to support our teaching staff and to influence changes in teaching and learning practices within the Department. The Plant Sciences Pedagogy Project used a number of qualitative and quantitative educational research methods in order to identify key plant sciences specific teaching and learning issues. These methods included practice-value questionnaires, self-efficacy questionnaires, supervision video analysis, student focus groups and supervisor interviews, which were implemented over the course of two academic years. The research findings were used to inform the development of a number of new learning resources which were provided for students within a virtual learning environment (VLE), or in collaborative workshops. The impact of the implementation of these new resources was assessed in order to inform research and development for the next academic year. In this paper, we describe the development of the research conducted in the Department of Plant Sciences and also chart the involvement of embedded researchers in the formation of the TfLN. The research structure is initially described in association with action research methodology but it is argued that the format has developed throughout the formation of TfLN so that it is best aligned with theories of social network analysis (Granovetter, 1973). This paper uses the theoretical perspective of brokerage between communities of practice (Burt, 2005; Wenger, 1998) to describe the role that plant science researchers have played in conducting research concerned with initiating changes in teaching and learning practices and also the subsequent coconfiguration of the TfLN research community. Burt’s (2005) four levels of brokerage are used to structure the discussion of these research processes, and the boundary crossing objects that have been used to support brokerage activities are described

    The erbia-hafnia system

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    Changing patterns of human resource management in construction

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    Recent years have seen increased emphasis on the need for construction organizations to be more client and market oriented—a tantalizing vision of a new quality world driven by clients with an emphasis on best value. This is likely to have significant implications for the business model and management in the industry. However, while construction constitutes an important component of global economic activity, and the very nature of the work is labour intensive, there has been a lack of attention given to the study of human resource management issues. Yet it has long been recognized that the way employees are managed can have important implications for organizational performance, and can even be a differentiator between successful and unsuccessful organizations (Marchington and Wilkinson, 2012). Context-specific factors are believed to partly explain typical approaches to managing people in the sector. These include the nature of complex project-based environments, ingrained cultural norms, cyclical demand and structural flexibility. Delivery of construction projects often requires the coordination of a multiplicity of actors, within a largely fragmented, transient and heterogeneous workforce. The construction industry therefore offers a rich and distinctive context for the study of employment issues, and an interesting counterpoint to the employment models traditionally associated with many manufacturing or service contexts. Much of the existing research tends to paint a fairly bleak picture of employment practices and industrial relations in the construction sector, often depicted as an informal, casualized and even cavalier approach to the management of people with long working hours (Lingard et al., 2008; Townsend et al., 2011) and high rates of health and safety incidents (Loudoun, 2010). Though management styles clearly vary between firms and across countries, thus making it difficult to generalize, the construction industry has been beset by a poor image in relation to approaches to human resource management and workforce relations (International Labour Office, 2001). In contrast to the model of HRM developed by Storey (1995) which emphasizes an approach to people management concerned with developing and utilizing employees in pursuit of organizational objectives, people management in construction is often characterized as a ‘black hole’ or ‘hard HRM’. Perhaps it is a by-product of the gendered nature of the construction industry, but Ness and Green (2012) report hostility of project managers towards HRM as a concept, citing evidence from managers who described investment in HR as ‘a luxury’, ‘namby-pamby’ and viewed HR practitioners as ‘pen pushers’. Indeed the British government has published various reports exhorting the need for a review of traditional employment practices, for both economic and social reasons. Encouragingly, there is also some evidence of the existence of more ‘enlightened’ approaches to managing people. This special issue aims to take stock and evaluate such changes

    GDNF secreted from adipose-derived stem cells stimulates VEGF-independent angiogenesis

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    Adipose tissue stroma contains a population of mesenchymal stem cells (MSC) promote new blood vessel formation and stabilization. These adipose-derived stem cells (ASC) promote de novo formation of vascular structures in vitro. We investigated the angiogenic factors secreted by ASC and discovered that glial-derived neurotrophic factor (GDNF) is a key mediator for endothelial cell network formation. It was found that both GDNF alone or present in ASC-conditioned medium (ASC-CM) stimulated capillary network formation by using human umbilical vein endothelial cells (HUVECs) and such an effect was totally independent of vascular endothelial growth factor (VEGF) activity. Additionally, we showed stimulation of capillary network formation by GDNF, but not VEGF, could be blocked by the Ret (rearranged during transfection) receptor antagonist RPI-1, a GDNF signaling inhibitor. Furthermore, GDNF were found to be overexpressed in cancer cells that were resistant to the anti-angiogenic treatment using the VEGF antibody. Cancer cells in the liver hepatocellular carcinoma (HCC), a non-nervous related cancer, highly overexpressed GDNF as compared to normal liver cells. Our data strongly suggest that, in addition to VEGF, GDNF secreted by ASC and HCC cells, may be another important factor promoting pathological neovascularization. Thus, GDNF may be a potential therapeutic target for HCC and obesity treatments

    HUMAN ADIPOSE-DERIVED STEM CELLS ATTENUATE CIGARETTE SMOKE INDUCED BONE MARROW HYPOPLASIA VIA SECRETION OF ANTI-INFLAMMATORY CYTOKINE TSG-6

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    poster abstractIntroduction We have previously observed bone marrow (BM) hypo-plasia in a murine model of chronic smoking, which was ameliorated by mu-rine adipose-derived stromal cells (ASC). This study was designed to test the hypothesis that ASC exert their marrow protective effects through key paracrine factors. Methods Mice (NSG or C57BL/6) were exposed to ciga-rette smoke (CS) for 1 day to 6 months. Human ASC or ASC conditioned media were administered through intravenous (i.v.) or intraperitoneal (i.p.) injections. Secretion of TSG-6 from ASC in response to TNF alpha and IL-1 beta were measured by ELISA. Expression of TSG-6 in ASC was knocked down by siRNA. BM hematopoietic progenitors were quantified by colony forming-unit assays. Possible engrafted human ASC in mouse BM were ex-amined by anti-human nuclei staining. Results The myelossupressive effect of cigarette smoking occurred acutely (1 day: 65.6% of nonsmoking control, NSC, p0.05) or ASC conditioned media (105.7% NSC, p>0.05). Inflammatory cytokines (TNF alpha and IL-1 beta) elevated in smokers (Kuschner et al, 1996; de Maat et al, 2002) demonstrated strong cross-species stimulatory effects on secretions of an anti-inflammatory cytokine, TSG-6 from ASC (TNF alpha: 8.7 +/- 1.3 fold, IL-1 beta: 8.2 +/- 1.1 fold). Knocking down TSG-6 (>90%) abolished the marrow-protective effect of ASC. No human cells were detected in recipient mouse bone marrow. Conclusions The pro-tective effects of ASC against smoking-induced myelosuppression are medi-ated by trophic factors rather than cell engraftment or differentiation. TSG-6 appears to play a significant role in the modulatory pathway: smoke--inflammatory cytokine release--TSG6 secretion from ASC--bone marrow protection

    Survey of the needs of patients with spinal cord injury: impact and priority for improvement in hand function in tetraplegics\ud

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    Objective: To investigate the impact of upper extremity deficit in subjects with tetraplegia.\ud \ud Setting: The United Kingdom and The Netherlands.\ud \ud Study design: Survey among the members of the Dutch and UK Spinal Cord Injury (SCI) Associations.\ud \ud Main outcome parameter: Indication of expected improvement in quality of life (QOL) on a 5-point scale in relation to improvement in hand function and seven other SCI-related impairments.\ud \ud Results: In all, 565 subjects with tetraplegia returned the questionnaire (overall response of 42%). Results in the Dutch and the UK group were comparable. A total of 77% of the tetraplegics expected an important or very important improvement in QOL if their hand function improved. This is comparable to their expectations with regard to improvement in bladder and bowel function. All other items were scored lower.\ud \ud Conclusion: This is the first study in which the impact of upper extremity impairment has been assessed in a large sample of tetraplegic subjects and compared to other SCI-related impairments that have a major impact on the life of subjects with SCI. The present study indicates a high impact as well as a high priority for improvement in hand function in tetraplegics.\ud \u

    Intracoronary and retrograde coronary venous myocardial delivery of adipose-derived stem cells in swine infarction lead to transient myocardial trapping with predominant pulmonary redistribution

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    OBJECTIVES: To examine the comparative fate of adipose-derived stem cells (ASCs) as well as their impact on coronary microcirculation following either retrograde coronary venous (RCV) or arterial delivery. BACKGROUND: Local delivery of ASCs to the heart has been proposed as a practical approach to limiting the extent of myocardial infarction. Mouse models of mesenchymal stem cell effects on the heart have also demonstrated significant benefits from systemic (intravenous) delivery, prompting a question about the advantage of local delivery. There has been no study addressing the extent of myocardial vs. systemic disposition of ASCs in large animal models following local delivery to the myocardium. METHODS: In an initial experiment, dose-dependent effects of ASC delivery on coronary circulation in normal swine were evaluated to establish a tolerable ASC dosing range for intracoronary (IC) delivery. In a set of subsequent experiments, an anterior acute myocardial infarction (AMI) was created by balloon occlusion of the proximal left anterior descending (LAD) artery, followed by either IC or RCV infusion of 10(7) (111)Indium-labeled autologous ASCs 6 days following AMI. Indices of microcirculatory resistance (IMR) and coronary flow reserve (CFR) were measured before sacrifices to collect tissues for analysis at 1 or 24 hr after cell delivery. RESULTS: IC delivery of porcine ASCs to normal myocardium was well tolerated up to a cumulative dose of 14 × 10(6) cells (approximately 0.5 × 10(6) cells/kg). There was evidence suggesting microcirculatory trapping of ASC: at unit doses of 50 × 10(6) ASCs, IMR and CFR were found to be persistently altered in the target LAD distribution at 7 days following delivery, whereas at 10 × 10(6) ASCs, only CFR was altered. In the context of recent MI, a significantly higher percentage of ASCs was retained at 1 hr with IC delivery compared with RCV delivery (57.2 ± 12.7% vs. 17.9 ± 1.6%, P = 0.037) but this initial difference was not apparent at 24 hr (22.6 ± 5.5% vs. 18.7 ± 8.6%; P = 0.722). In both approaches, most ASC redistributed to the pulmonary circulation by 24 hr postdelivery. There were no significant differences in CFR or IMR following ASC delivery to infarcted tissue by either route. CONCLUSIONS: Selective intravascular delivery of ASC by coronary arterial and venous routes leads to similarly limited myocardial cell retention with predominant redistribution of cells to the lungs. IC arterial delivery of ASC leads to only transiently greater myocardial retention, which is accompanied by obstruction of normal regions of coronary microcirculation at higher doses. The predominant intrapulmonary localization of cells following local delivery via both methods prompts the notion that systemic delivery of ASC might provide similarly beneficial outcomes while avoiding risks of inadvertent microcirculatory compromise

    Adipose-derived Stem Cell Conditioned Media Extends Survival time of a mouse model of Amyotrophic Lateral Sclerosis

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    Adipose stromal cells (ASC) secrete various trophic factors that assist in the protection of neurons in a variety of neuronal death models. In this study, we tested the effects of human ASC conditional medium (ASC-CM) in human amyotrophic lateral sclerosis (ALS) transgenic mouse model expressing mutant superoxide dismutase (SOD1(G93A)). Treating symptomatic SOD1(G93A) mice with ASC-CM significantly increased post-onset survival time and lifespan. Moreover, SOD1(G93A) mice given ASC-CM treatment showed high motor neuron counts, less activation of microglia and astrocytes at an early symptomatic stage in the spinal cords under immunohistochemical analysis. SOD1(G93A) mice treated with ASC-CM for 7 days showed reduced levels of phosphorylated p38 (pp38) in the spinal cord, a mitogen-activated protein kinase that is involved in both inflammation and neuronal death. Additionally, the levels of α-II spectrin in spinal cords were also inhibited in SOD1(G93A) mice treated with ASC-CM for 3 days. Interestingly, nerve growth factor (NGF), a neurotrophic factor found in ASC-CM, played a significant role in the protection of neurodegeneration inSOD1(G93A) mouse. These results indicate that ASC-CM has the potential to develop into a novel and effective therapeutic treatment for ALS

    Threshold Concepts as Focal Points for Supporting Student Learning

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    The Plant Sciences Pedagogy Project conducted research into undergraduate teaching and learning in the Department of Plant Sciences at the University of Cambridge and has translated the research findings into interventions to improve support for student learning. A key research objective for the project was to investigate how teachers within the Department support student learning in small group tutorials. This was undertaken using questionnaires, focus groups and interviews. During focus groups students reported that they valued tutors who were able to anticipate topics that they found difficult to master. The threshold concepts framework provided a medium for discussion about these troublesome areas in this discipline area and a number of threshold concepts were identified by interviewing teaching staff. The topics that emerged from this were used as focal points for development of new online resources for students. As threshold concepts are typically difficult to teach, they are challenging to one’s own practice as a teacher. Threshold concepts may provide a good focus for continuing professional development of teaching staff
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