An evaluation of exercises for the development of word recognition and word meaning in grade five

Thesis (Ed.M.)--Boston Universit

An evaluation of exercises for the development of word recognition and word meaning in grade five

Thesis (Ed.M.)--Boston Universit

VOLCANS: an objective, structured and reproducible method for identifying sets of analogue volcanoes

The definition of a suite of analogue volcanoes, or volcanoes that are considered to share enough characteristics as to be considered exchangeable to a certain extent, is becoming a key component of volcanic hazard assessment. This is particularly the case for volcanoes where data are lacking or scarce. Moreover, volcano comparisons have often been based on similarities and differences inferred through expert judgement and not necessarily informed by volcano characteristics from global datasets. These similarities can be based on a range of features, from very simplified (e.g. statrovolcanoes) to very specific (e.g. detailed eruption chronologies), and may be strongly influenced by the personal experience of individuals or teams conducting the analogue analysis. In this work, we present VOLCANS (VOLCano ANalogues Search)—an objective, structured and reproducible method to identify sets of analogue volcanoes from global volcanological databases. Five overarching criteria (tectonic setting, rock geochemistry, volcano morphology, eruption size and eruption style), and a structured combination of them, are used to quantify overall multi-criteria volcano analogy. This innovative method is complementary to expert-derived sets of analogue volcanoes and provides the user with full flexibility to weigh the criteria and identify analogue volcanoes applicable to varied purposes. Some results are illustrated for three volcanoes with diverse features and significant recent and/or ongoing eruptions: Kı̄lauea (USA), Fuego (Guatemala) and Sinabung (Indonesia). The identified analogue volcanoes correspond well with a priori analogue volcanoes derived from expert knowledge. In some cases, single-criterion searches may not be able to isolate a reduced set of analogue volcanoes but any multi-criteria search can provide high degrees of granularity in the sets of analogue volcanoes obtained. Data quality and quantity can be important factors, especially for single-criterion searches and volcanoes with very scarce data (e.g. Sinabung). Nevertheless, the method gives stable results overall across multi-criteria searches of analogue volcanoes. Potential uses of VOLCANS range from quantitative volcanic hazard assessment to promoting fundamental understanding of volcanic processes

A proteomic analysis of chondrogenic, osteogenic and tenogenic constructs from ageing mesenchymal stem cells

Background Mesenchymal stem cells (MSCs) have prospective applications in regenerative medicine and tissue engineering but to what extent phenotype and differentiation capacity alter with ageing is uncertain. Consequently, any loss in functionality with age would have profound consequences for the maintenance of tissue viability and the quality of tissues. Proteomics enables the set of proteins responsible for a particular cell phenotype to be identified, as well as enabling insights into mechanisms responsible for age-related alterations in musculoskeletal tissues. Few proteomic studies have been undertaken regarding age-related effects on tissue engineered into cartilage and bone, and none for tendon. This study provides a proteome inventory for chondrogenic, osteogenic and tenogenic constructs synthesised from human MSCs, and elucidates proteomic alterations as a consequence of donor age. Methods Human bone-marrow derived MSCs from young (n = 4, 21.8 years ± 2.4SD) and old (n = 4, 65.5 years ± 8.3SD) donors were used to make chondrogenic, osteogenic and tenogenic tissue-engineered constructs. We utilised an analytical method relying on extracted peptide intensities as a label-free approach for peptide quantitation by liquid chromatography–mass spectrometry. Results were validated using western blotting. Results We identified proteins that were differentially expressed with ageing; 128 proteins in chondrogenic constructs, 207 in tenogenic constructs and four in osteogenic constructs. Differentially regulated proteins were subjected to bioinformatic analysis to ascertain their molecular functions and the signalling pathways. For all construct types, age-affected proteins were involved in altered cell survival and death, and antioxidant and cytoskeletal changes. Energy and protein metabolism were the principle pathways affected in tenogenic constructs, whereas lipid metabolism was strongly affected in chondrogenic constructs and mitochondrial dysfunction in osteogenic constructs. Conclusions Our results imply that further work on MSC-based therapeutics for the older population needs to focus on oxidative stress protection. The differentially regulated proteome characterised by this study can potentially guide translational research specifically aimed at effective clinical interventions

3D geological models and their hydrogeological applications : supporting urban development : a case study in Glasgow-Clyde, UK

Urban planners and developers in some parts of the United Kingdom can now access geodata in an easy-to-retrieve and understandable format. 3D attributed geological framework models and associated GIS outputs, developed by the British Geological Survey (BGS), provide a predictive tool for planning site investigations for some of the UK's largest regeneration projects in the Thames and Clyde River catchments. Using the 3D models, planners can get a 3D preview of properties of the subsurface using virtual cross-section and borehole tools in visualisation software, allowing critical decisions to be made before any expensive site investigation takes place, and potentially saving time and money. 3D models can integrate artificial and superficial deposits and bedrock geology, and can be used for recognition of major resources (such as water, thermal and sand and gravel), for example in buried valleys, groundwater modelling and assessing impacts of underground mining. A preliminary groundwater recharge and flow model for a pilot area in Glasgow has been developed using the 3D geological models as a framework. This paper focuses on the River Clyde and the Glasgow conurbation, and the BGS's Clyde Urban Super-Project (CUSP) in particular, which supports major regeneration projects in and around the City of Glasgow in the West of Scotland

Microscopic biophysical model of self-organization in tissue due to feedback between cell- and macroscopic-scale forces

We develop a microscopic biophysical model for self-organization and reshaping of artificial tissue, that is codriven by microscopic active forces between cells and an extracellular matrix (ECM), and macroscopic forces that develop within the tissue, finding close agreement with experiment. Microscopic active forces are stimulated by μ m -scale interactions between cells and the ECM within which they exist, and when large numbers of cells act together these forces drive, and are affected by, macroscopic-scale self-organization and reshaping of tissues in a feedback loop. To understand this loop, there is a need to (1) construct microscopic biophysical models that can simulate these processes for the very large number of cells found in tissues, (2) validate and calibrate those models against experimental data, and (3) understand the active feedback between cells and the extracellular matrix, and its relationship to macroscopic self-organization and reshaping of tissue. Our microscopic biophysical model consists of a contractile network representing the ECM, that interacts with a large number of cells via dipole forces, to describe macroscopic self-organization and reshaping of tissue. We solve the model using simulated annealing, finding close agreement with experiments on artificial neural tissue. We discuss the calibration of model parameters. We conclude that feedback between microscopic cell-ECM dipole interactions and tissue-scale forces is a key factor in driving macroscopic self-organization and reshaping of tissue. We discuss the application of the biophysical model to the simulation and rational design of artificial tissues

Adapting tissue-engineered in vitro CNS models for high-throughput study of neurodegeneration

Neurodegenerative conditions remain difficult to treat, with the continuing failure to see therapeutic research successfully advance to clinical trials. One of the obstacles that must be overcome is to develop enhanced models of disease. Tissue engineering techniques enable us to create organised artificial central nervous system tissue that has the potential to improve the drug development process. This study presents a replicable model of neurodegenerative pathology through the use of engineered neural tissue co-cultures that can incorporate cells from various sources and allow degeneration and protection of neurons to be observed easily and measured, following exposure to neurotoxic compounds - okadaic acid and 1-methyl-4-phenylpyridinium. Furthermore, the technology has been miniaturised through development of a mould with 6 mm length that recreates the advantageous features of engineered neural tissue co-cultures at a scale suitable for commercial research and development. Integration of human-derived induced pluripotent stem cells aids more accurate modelling of human diseases, creating new possibilities for engineered neural tissue co-cultures and their use in drug screening