2,976 research outputs found
C.A. Parker's Store
No full textPhotograph - A dog team and a loaded sled on Strathcona Street in front of C.A. Parker's store, Athabasca, Albert
Eigen schuld van de architect
No full textRede, uitgesproken bij het afscheid als buitengewoon hoogleraar in het bouw- en woning recht aan de Technische Hogeschool Delft op vrijdag 21 februari 1986 door prof.mr C.A. Adriaansens.Architectur
C.A. McGill, March 23, 1918
No full textPortrait of C.A. McGill. Written on verso: With love from C.A. McGill Monrovia, Liberia, March 23rd, 1918.The Atlanta University Center Robert W. Woodruff Library acknowledges the generous support of the National Endowment for Humanities - Humanities Collections and Reference Resources Implementation Project Grant in supporting the processing and digitization of a number of its major archival collections as part of the project: Spreading the Word: Expanding Access to African American Religious Archival Collections at the Atlanta University Center Robert W. Woodruff Library.</em
Erratum: Future temperature extremes will be more harmful: A new critical factor for improved forecasts (Int. J. Environ. Res. Public Health 2019, 16 (20), 4015)
No full textThe authors would like to correct the names and surnames of both authors of their previous paper [1] as follows: Costas A. Varotsos1,2,* and Yuri A. Mazei2 Therefore, to cite this paper please use the correct reference as follows: Varotsos, C.A.; Mazei,Y.A. Future Temperature Extremes Will Be More Harmful: A New Critical Factor for Improved Forecasts. Int. J. Environ. Res. Public Health 2019, 16 (20), 4015. © 2020 by the author. Licensee MDPI, Basel, Switzerland
Synthesis and characterization of phthalonitrile resins from ortho-linked aromatic and heterocyclic monomers
No full textThis article describes the synthesis and properties of phthalonitrile polymers prepared from three different ortho-linked monomers, namely 2,2′-bis(3,4-dicyanophenoxy)biphenyl, 1,2-bis(3,4-dicyanophenoxy)benzene and 2,2′-bis(3,4-dicyanophenoxy)-1,3,4-oxadiazole. The resins exhibited a low complex viscosity, with a varying range of processing temperatures for all three systems. Thermogravimetric analysis showed that the synthesized polymers exhibited high thermal and thermo-oxidative stability. The high char yields, which ranged from 64 to 69% at 900 °C under nitrogen atmosphere, and the high glass transition temperatures of the polymers indicated a high crosslinking density in the network structure. Dynamic mechanical measurements demonstrated that the fully cured monomer 2,2′-bis(3,4-dicyanophenoxy)-1,3,4-oxadiazole exhibited no change in glass transition temperature or in storage modulus up to 500 °C.A. Badshah, M. R. Kessler, Z. Heng, A. Hasan: Synthesis and Characterization of Phthalonitrile Resins from Ortho-Linked Aromatic and Heterocyclic Monomers, Polymer International, 2014, 63, 465-469. DOI: 10.1002/pi.4527
Skeleton-based design and simulation flow for Computation-in-Memory architectures
No full textMemristor-based Computation-in-Memory is one of the emerging architectures proposed to deal with Big Data problems. The design of such architectures requires a radically new automatic design flow because the memristor is a passive device that uses resistance to encode its logic value. This paper proposes a design flow for mapping parallel algorithms on the CIM architecture. Algorithms with similar data flow graphs can be mapped on the crossbar using the same template containing scheduling, placement, and routing information; this template is named skeleton. By configuring such a skeleton with different pre-designed circuits, we can build CIM implementations of the corresponding algorithms in that class. This approach does not only map an algorithm on a memristor crossbar, but also gives an estimation of its performance, area, and energy consumption. It also supports user-defined constraints and parallel SystemC simulation. Experimental results demonstrate the feasibility and the potential of the approach.Accepted Author ManuscriptComputer EngineeringQuantum & Computer EngineeringFTQC/Bertels La
Thoughts about cancer stem cells in solid tumors
No full textCancer chemotherapy efficacy is frequently impaired by either intrinsic or acquired tumor resistance. A fundamental problem in cancer research is identifying the cell type that is capable of sustaining neoplastic growth and its origin from normal tissue cells. In recent years, the cancer stem cell (CSC) theory has changed the classical view of tumor growth and therefore the therapeutic perspective. Overcoming intrinsic and acquired resistance of cancer stem/progenitor cells to current clinical treatments represents a major challenge in treating and curing the most aggressive and metastatic cancers. On the other hand, the identification of CSCs in vivo and in vitro relies on specific surface markers that should allow the sorting cancer cells into phenotypically distinct subpopulations. In the present review, recent papers published on CSCs in solid tumors (breast, prostate, brain and melanoma) are discussed, highlighting critical points such as the choice of markers to sort CSCs and mouse models to demonstrate that CSCs are able to replicate the original tumor. A discussion of the possible role of aldehyde dehydrogenase and CXCR6 biomarkers as signaling molecules in CSCs and normal stem cells is also discussed. The author believes that efforts have to be made to investigate the functional and biological properties of putative CSCs in cancer. Developing diagnostic/prognostic tools to follow cancer development is also a challenge. In this connection it would be useful to develop a multidisciplinary approach combining mathematics, physics and biology which merges experimental approaches and theory. Biological models alone are probably unable to resolve the problem completely
Letter from unknown writer to Jesse L. Boyce
No full textLetter to Jesse L. Boyce from unknown author (possibly Jack) about the investigation into the powder magazine located in the Grand Canyon. Some personal news is included in the letter such as the writer's marriage to the daughter of C.A. Taylor, former Supervisor of Cochise County
A set of nine principles for distributed-design information storing
No full textThe issues of distributed working are many, with problems relating to information access and information acquisition the most common (Crabtree et al., 1997). Keeping track of project and team information is becoming more complex as design is increasingly being carried out collaboratively by geographically dispersed design teams across different time zones. The literature notes that little prescription or guidance exists on information management for designers (Culley et al., 1999) and Hicks (2007) highlights a relative lack of overall principles for improving information management. Additionally, evidence from earlier studies by the author into ‘How information is stored in distributed design project work’ reinforces the need for guidance, particularly in a distributed context (Grierson, 2008). Distributed information collections were found to be unorganised, contained unclear information and lacked context. Storing and sharing of distributed information was often time consuming and the tools awkward to use. This can lead to poor project progress and can impact directly on the quality and success of project outcomes (Grierson et al., 2004, 2006). This paper seeks to address these issues by presenting the development, implementation and evaluation of a set of Principles and a Framework to support distributed design information storing in the context of a Global Design class. Through both quantitative and qualitative evaluation methods the Principles were found to help in a number of ways – with the easy access of information; the structuring and organising of information; the creation of an information strategy; the making of information clear and concise; the supporting of documentation during project work; and the strengthening of team work; all helping teams to work towards project outcomes
Exploring the scaling-up of sustainable land management in the Central highlands of Ethiopia
No full textIn Ethiopia’s struggle to enhance agricultural production and attain food security, combating land degradation remains a huge challenge; particularly in the highlands of the country where the large majority of the population is dependent on subsistence agriculture for their living. Sustainable Land Management (SLM) is therefore crucial, and over the past decades, massive investments have been made in Ethiopia to promote and scale-up SLM practices. However, large-scale adoption of these practices by smallholder farmers has so far been limited. Nevertheless, there are examples of farmers who have spontaneously adopted SLM practices. These farmers – using their own knowledge and capacity – often adapt practices to make them fit to their particular farming system, and integrate them with other land management measures. The overall aim of this study was to analyze this process of spontaneous spreading (i.e. the adoption and implementation of measures by farmers on their own initiative) and learn lessons that could contribute to developing the way forward in scaling-up SLM in the Central Highlands of Ethiopia. Chapter 2 deals with the comparison between stone bunds that were spread spontaneously versus stone bunds implemented by mass mobilization campaigns. The results show that farmers who spontaneously implement stone bunds prefer to construct them on farmlands located nearby the homestead, often with a poor to medium soil fertility status, where erosion is perceived as moderate to severe, and which have moderate to steep slope gradients. This means that stone bunds spontaneously spread mainly where they were most needed. Farmers with spontaneously implemented stone bunds perceive a reduction in soil erosion, increase in soil moisture, better soil productivity and higher crop yields on these farmlands. These positive effects are the result of the fact that stone bunds of the spontaneous adopting farmers are well-maintained and integrated with the use of fertilizer, compost and manure. The lesson learned from this chapter is that SLM activities undertaken by mass mobilization should become more integrated and participatory, as learning and testing innovations by farmers enhances adoption of SLM practices. Following up on the previous chapter, Chapter 3 focuses on the characteristics of farmers that spontaneously implement stone bunds and farmers who do not. Using Principal Component Analysis, the study identified five key-factors that explain the differences between farmers who spontaneously implement stone bunds and those who do not. These include readiness to change, available resources, social capital, type of family and commitment. The results show that farmers who spontaneously implemented stone bunds are: 1) young farmers committed to soil conservation, 2) intrinsically motivated dynamic farmers ready to change their future and improve productivity and food security, and 3) farmers with relatively limited productive resources such as farmland, labor and livestock, but with more willingness to improve their agricultural production, relying on available resources and social capital. This implies that government extension programs aiming to sustainably increase agricultural production and achieve food security of smallholder farmers in Ethiopia should be more focused on triggering farmers’ “readiness to change”, and foster their intrinsic motivation to implement SLM. Likewise, the results show that implementation of SLM relies more on farmers having a positive attitude and commitment, rather than having the resources available like labor forces and money. Hence, changing farmers’ mind-set through training and learning is crucial to foster SLM in Ethiopia. Chapter 4 explores the effect of an adapted (more participatory and more integrated) mass mobilization training approach on farmers’ motivation to practice integrated farming. This study was based on the results of a one-year field experiment carried out in the Central Highlands of Ethiopia. The results show that the adapted training approach enhanced awareness of farmers, created intrinsic motivation for integrated farm management and fostered implementation of SLM practices in the field. It also reveals that farmers who followed the training are better able to plan for future drought mitigation and are more aware of the possible effects of drought on their farming activities. The results imply that agricultural extension programs that aim at scaling-up of resilient farming to watershed and landscape levels should start with capacity building by means of participatory training methods, and by empowering and motivating farmers for integrated SLM. Chapter 5 focuses on the policy and institutional environment of Ethiopia required to speed-up the scaling-up of SLM. It identifies perceived limitations at the national, regional and local level hindering the scaling-up of SLM practices, and finds that these relate to the process of policy formulation and implementation, the available institutional capacity, and collaboration between institutions. Particularly limiting are the top-down approaches used for planning, implementing and monitoring; these neglect farmers’ knowledge and their priority needs. However, lack of capacity within institutions to scale-up SLM practices is another crucial issue: decision-makers have very limited knowledge about SLM practices and measures, while extension workers and officials do not transfer their knowledge and have to deal with high staff turnover. Furthermore, there is often poor coordination, collaboration and communication between different institutional levels, which also hinders a more effective and structured scaling-up of SLM practices. Changing the policy and institutional environment of Ethiopia is therefore urgently required, by means of creating supportive policies, building the institutional capacity, and strengthening institutional collaboration and networking. Chapter 6 presents a synthesis of the previous chapters. It provides answers to the research questions, and discusses the major findings of the study. It also presents the extension and policy implications, scientific contributions of the thesis, and suggestions for future research. The main insight from this thesis is that a shift towards a more participatory and integrated approach for SLM is urgently required to genuinely tackle land degradation in the highlands of Ethiopia. Participatory approaches empower farmers to make decisions themselves and enable them to invest in diverse SLM practices that they think can solve their priority problems such as low soil fertility. Likewise, promoting SLM technologies in a more integrated manner contributes to increased food production, and diversified production and higher incomes. Furthermore, Chapter 6 presents the general conclusions drawn from the findings of the study. The chapter concludes that: In order to sustainably enhance the productive capacity of smallholder farmers and increase their food security, more focus on training and enhancing farmers’ intrinsic motivation to improve their livelihood is necessary. More focus on participatory planning and learning in the mass mobilization strategy is crucial, as this improves farmers’ sense of ownership of SLM practices and increases their motivation to participate in conservation activities. The strategies for scaling-up SLM practices in the central highlands of Ethiopia should shift towards more integrated soil fertility management, rather than focusing mainly on physical conservation practices. Government investments in creating an adequate enabling environment for scaling-up SLM are urgently required, as many limitations at institutional level currently hinder the spreading and effectiveness of SLM efforts. </ul
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