51 research outputs found

    Monitored Indoor Environmental Quality of a Mass Timber Office Building: A Case Study

    Get PDF
    A broad range of building performance monitoring, sampling, and evaluation was conducted periodically after construction and spanning more than a year, for an occupied office building constructed using mass timber elements such as cross-laminated timber (CLT) floor and roof panels, as well as glue-laminated timber (GLT) beams and columns. This case study contributes research on monitoring indoor environmental quality in buildings, describing one of the few studies of an occupied mass timber building, and analyzing data in three areas that impact occupant experience: indoor air quality, bacterial community composition, and floor vibration. As a whole, the building was found to perform well. Volatile organic compounds (VOCs), including formaldehyde, were analyzed using multiple methods. Formaldehyde was found to be present in the building, though levels were below most recommended exposure limits. The source of formaldehyde was not able to be identified in this study. The richness of the bacterial community was affected by the height of sampling with respect to the floor, and richness and composition was aected by the location within the building. Floor vibration was observed to be below recognized human comfort thresholds

    Selecting sites to prove the concept of IAR4D in the Lake Kivu Pilot Learning Site

    Get PDF
    Selecting sites is an essential step in enabling the assessment of the impact of Integrated Agricultural Research for Development (IAR4D) in the Lake Kivu Pilot Learning Site. This paper reports on the process of identifying distinct administrative territories (sites) in which to establish innovation platforms and to monitor similar communities that are experiencing alternative agricultural research for development interventions. We show how the research design for the Sub- Saharan Africa Challenge Programme (SSACP) has been modified to take into account the key conditioning factors of the LKPLS without relinquishing robustness. A key change is the explicit incorporation of accessibility to multiple markets. Candidate sites were stratified according to the national political context, followed by good and poor accessibility to markets and finally according to security considerations and agro-ecology. Randomisation was carried out at all levels, although the need for paired counterfactual sites required the diagnosis of conditioning factors at the site level. Potential sites were characterised in terms of existing or recent agricultural research initiatives, as well as local factors that would have a direct effect on the success of interventions seeking to improve productivity, ameliorate the degradation of natural resources and enhance incomes through better links to markets. Fourteen sites were selected during the initial phase, and a further ten sites were added one year afterwards due to the need for more innovation platforms to test IAR4D. The site selection was successful in pairing action and counterfactual sites in terms of the baseline socioeconomic conditions of farming households. The unavoidable proximity of action and counterfactual sites, however, allows the possibility of spill-over effects and could reduce the measurable impact of IAR4D

    Institutional Innovations for Building Impact-oriented Agricultural Research, Knowledge and Development Institutions

    Get PDF
    The central development question in African agriculture is how to catalyze a more competitive, equitable and sustainable agricultural growth within the context of smallholder production systems, inefficient agricultural marketing, inefficient investments by private sector amidst degradation prone natural resources base (Lynam and Blackie, 1994; IAC, 2004; World bank, 2006 ). Concerted scholarly analyses of Science and Technology (S&T) strategies have given birth to Integrated Agricultural Research for Development (IAR4D) an organizing concept of the Innovation Systems Approach (ISA) as the promise holder. It is hypothesized that the generation, diffusion and application of impactful innovations critically depend on systemic integration of knowledge systems that promote communication, interaction and cooperation between agricultural research, education, extension, farmers, private sector and policy regulatory systems. This paper examines how the different institutional innovations arising from various permutations of linkages and interactions of ARD organizations (national, international advanced agricultural research centres and universities) influenced the different outcomes in addressing identified ARD problems. A multi-institutional, multi-disciplinary phased Participatory Action Research approach was used to pool knowledge to address outstanding and emerging challenges in three countries (DRC, Rwanda and Uganda) with 2, 16 and 24 years out of conflict, respectively) of the Lake Kivu Pilot Learning Site. A landmark institutional innovation was the participatory establishment of twelve (12) Innovation Platforms as tools for pooling knowledge across the agricultural business, education, research and extension systems. The knowledge “pool” was to generate, diffuse and apply innovations to reduce transactions costs and create value chain based “win-win” situations. A number of innovations (e.g. International Public Goods-IPGs, market binding contracts, registered brands and/or certification processes, diversity, density and quality of networks/collective action, bulking centres, ICT application and depth of knowledge pools) were initiated. There were major breakthroughs which included bringing on board non-traditional private sector and policy maker partners, overcoming the predominant “farmer handout syndrome”, building consensus and addressing common interest challenge. Making markets work, bringing various stakeholders including universities to the community and vice-versa, appreciation of indigenous knowledge system, propelling collective soil and water conservation and demand/utilization of technologies hitherto on-shelf were other very significant breakthroughs. Sustainable operations of the Innovation Systems knowledge “pool” nurturing institutional learning were ensured through the availability of a “functional body”. The body undertook the social enterprise of organizing farmers and traders, facilitating/brokering ARD organization linkages by using multi-media to build social capital to overcome emergent knowledge, credit, market, technology and resource degradation challenges under different policy regulatory systems

    Does Diabetes Accelerate the Progression of Aortic Stenosis through Enhanced Inflammatory Response within Aortic valves?

    Get PDF
    Diabetes predisposes to aortic stenosis (AS). We aimed to investigate if diabetes affects the expression of selected coagulation proteins and inflammatory markers in AS valves. Twenty patients with severe AS and concomitant type 2 diabetes mellitus (DM) and 40 well-matched patients without DM scheduled for valve replacement were recruited. Valvular tissue factor (TF), TF pathway inhibitor (TFPI), prothrombin, C-reactive protein (CRP) expression were evaluated by immunostaining and TF, prothrombin, and CRP transcripts were analyzed by real-time PCR. DM patients had elevated plasma CRP (9.2 [0.74–51.9] mg/l vs. 4.7 [0.59–23.14] mg/l, p = 0.009) and TF (293.06 [192.32–386.12] pg/ml vs. 140 [104.17–177.76] pg/ml, p = 0.003) compared to non-DM patients. In DM group, TF−, TFPI−, and prothrombin expression within valves was not related to demographics, body mass index, and concomitant diseases, whereas increased expression related to DM was found for CRP on both protein (2.87 [0.5–9]% vs. 0.94 [0–4]%, p = 0.01) and transcript levels (1.3 ± 0.61 vs. 0.22 ± 0.43, p = 0.009). CRP-positive areas were positively correlated with mRNA TF (r = 0.84, p = 0.036). Diabetes mellitus is associated with enhanced inflammation within AS valves, measured by CRP expression, which may contribute to faster AS progression

    The contributions of muscarinic receptors and changes in plasma aldosterone levels to the anti-hypertensive effect of Tulbaghia violacea

    Get PDF
    Background: Tulbaghia violacea Harv. (Alliaceae) is used to treat various ailments, including hypertension (HTN) in South Africa. This study aims to evaluate the contributions of muscarinic receptors and changes in plasma aldosterone levels to its anti-hypertensive effect. Methods: In the acute experiments, methanol leaf extracts (MLE) of T. violacea (30–120 mg/kg), muscarine (0.16 -10 μg/kg), and atropine (0.02 - 20.48 mg/kg), and/or the vehicle (dimethylsulfoxide (DMSO) and normal saline (NS)) were respectively and randomly administered intravenously in a group of spontaneously hypertensive (SHR) weighing 300 to 350 g and aged less than 5 months. Subsequently, T. violacea (60 mg/kg) or muscarine (2.5 μg/kg) was infused into eight SHRs, 20 min after atropine (5.12 mg/kg) pre-treatment. In the chronic (21 days) experiments, the SHRs were randomly divided into three groups, and given the vehicle (0.2 ml/day of DMSO and NS), T. violacea (60 mg/kg/day) and captopril (10 mg/kg/day) respectively into the peritoneum, to investigate their effects on blood pressure (BP), heart rate (HR), and plasma aldosterone levels. Systolic BP and HR were measured using tail-cuff plethysmography during the intervention. BP and HR were measured via a pressure transducer connecting the femoral artery and the Powerlab at the end of each intervention in the acute experiment; and on day 22 in the chronic experiment. Results: In the acute experiments, T. violacea, muscarine, and atropine significantly (p < 0.05) reduced BP dose-dependently. T. violacea and muscarine produced dose-dependent decreases in HR, while the effect of atropine on HR varied. After atropine pre-treatment, dose-dependent increases in BP and HR were observed with T. violacea; while the BP and HR effects of muscarine were nullified. In the chronic experiments, the T. violaceatreated and captropril-treated groups had signicantly lower levels of aldosterone in plasma when compared to vehicle-treated group. Compared to the vehicle-treated group, significant reduction in BP was only seen in the captopril-treated group; while no difference in HR was observed among the groups. Conclusion: The results obtained in this study suggest that stimulation of the muscarinic receptors and a reduction in plasma aldosterone levels contribute to the anti-hypertesive effect of T. violacea.IS

    Principles, design and processes of integrated agricultural research for development: experiences and lessons from LKPLS under the SSACP

    Get PDF
    With increasing recognition holding the promise of overcoming the outstanding problems faced byAfrican agriculture, IAR4D faces the danger of being ‘blurred’ by past approaches and falling short of its potential to deliver the desired impacts in diverse multi-stakeholder, biophysical, socio- economic, cultural, technological and market contexts unless its actualisation and working is clearly understood. In this paper, we present the conceptualisation and principles of and knowledge-based experiences and lessons from the implementation of the sub-Saharan Africa Challenge Programme (SSACP) in the Lake Kivu Pilot Learning Site (LKPLS). The presentation covers the formation and facilitation of IPs for the actualisation of IAR4D to evolve mechanisms for the early recognition of interlinked issues in natural resource management, productivity and value addition technologies, markets, gender and policy arrangements. These have autonomously triggered flexible, locally directed interactions to innovate options from within or outside their environment for resolving the challenges, and have moved along a new institutional and technological change trajectory. Emerging lessons point to the endowment of IP members with selfhelp knowledge interactions, training in IAR4D, quality of facilitation and research to be key determinants of the power behind of self-regulating mechanisms

    The role of APOBEC3B in lung tumor evolution and targeted cancer therapy resistance

    Get PDF
    In this study, the impact of the apolipoprotein B mRNA-editing catalytic subunit-like (APOBEC) enzyme APOBEC3B (A3B) on epidermal growth factor receptor (EGFR)-driven lung cancer was assessed. A3B expression in EGFR mutant (EGFRmut) non-small-cell lung cancer (NSCLC) mouse models constrained tumorigenesis, while A3B expression in tumors treated with EGFR-targeted cancer therapy was associated with treatment resistance. Analyses of human NSCLC models treated with EGFR-targeted therapy showed upregulation of A3B and revealed therapy-induced activation of nuclear factor kappa B (NF-κB) as an inducer of A3B expression. Significantly reduced viability was observed with A3B deficiency, and A3B was required for the enrichment of APOBEC mutation signatures, in targeted therapy-treated human NSCLC preclinical models. Upregulation of A3B was confirmed in patients with NSCLC treated with EGFR-targeted therapy. This study uncovers the multifaceted roles of A3B in NSCLC and identifies A3B as a potential target for more durable responses to targeted cancer therapy.</p

    Uncovering the mechanisms of research capacity development in health and social care: a realist synthesis

    Get PDF
    BACKGROUND: Research capacity development (RCD) is considered fundamental to closing the evidence-practice gap, thereby contributing to health, wealth and knowledge for practice. Numerous frameworks and models have been proposed for RCD, but there is little evidence of what works for whom and under what circumstances. There is a need to identify mechanisms by which candidate interventions or clusters of interventions might achieve RCD and contribute to societal impact, thereby proving meaningful to stakeholders. METHODS: A realist synthesis was used to develop programme theories for RCD. Structured database searches were conducted across seven databases to identify papers examining RCD in a health or social care context (1998-2013). In addition, citation searches for 10 key articles (citation pearls) were conducted across Google Scholar and Web of Science. Of 214 included articles, 116 reported on specific interventions or initiatives or their evaluation. The remaining 98 articles were discussion papers or explicitly sought to make a theoretical contribution. A core set of 36 RCD theoretical and conceptual papers were selected and analysed to generate mechanisms that map across macro contexts (individual, team, organisational, network). Data were extracted by means of 'If-Then' statements into an Excel spreadsheet. Models and frameworks were deconstructed into their original elements. RESULTS: Eight overarching programme theories were identified featuring mechanisms that were triggered across multiple contexts. Three of these fulfilled a symbolic role in signalling the importance of RCD (e.g. positive role models, signal importance, make a difference), whilst the remainder were more functional (e.g. liberate talents, release resource, exceed sum of parts, learning by doing and co-production of knowledge). Outcomes from one mechanism produced changes in context to stimulate mechanisms in other activities. The eight programme theories were validated with findings from 10 systematic reviews (2014-2017). CONCLUSIONS: This realist synthesis is the starting point for constructing an RCD framework shaped by these programme theories. Future work is required to further test and refine these findings against empirical data from intervention studies

    The oxidizing role of CO2 at mild temperature on ceria-based catalysts

    No full text
    For thermodynamic reasons, CO2 has always been considered as inert at mild reaction temperatures (similar to 300 degrees C). In this study, we show that CO2 may be used as a valuable compound for the catalytic combustion of methane (CCM), if ceria-based materials are used as support for the palladium active phase. Adding CO2 in the feed significantly improves performances of ceria-zirconia supported catalysts. On the contrary, catalytic performances are inhibited on Pd/gamma-Al2O3. Inhibition can be avoided by mixing the Pd/gamma-Al2O3 catalyst with some CeO2 evidencing cooperation phenomena between both catalysts. In situ DRIFTS experiments show that the inhibition of the alumina-supported catalyst is not due to formation of carbonates species. After an in situ reducing pre-treatment, pure CO2 is able to rapidly oxidize reduced Pd/Ce0.21Zr0.79O2 catalyst at 300 degrees C. Dissociation of CO2 on Ce0.21Zr0.79O2 would be responsible for the oxidation process. Thus, CO2 helps in replenishing the O reservoir (OSC) of the Ce-Zr-O support which is normally consumed by reductants such as CH4, H-2 or other HC's. XPS experiments show enrichment in oxygen species bound to Ce (Low BE O1s) on the surface of ceria-zirconia when working in the presence of CO2. Implications of these results on the behavior of ceria-containing catalysts can be important for practical applications, e.g., in automotive exhaust catalysis. (c) 2006 Published by Elsevier B.V
    corecore