Development of a sediment yield model for South East Ghana in the regions around Lake Volta

Soil erosion is one of the most pressing issues facing developing countries. The need for soil erosion assessment is paramount as a successful and productive agricultural base is necessary for economic growth and stability. In Ghana, a country with an expanding population and high potential for economic growth, agriculture is an important resource; however, most of the crop production is restricted to low technology shifting cultivation agriculture. The high intensity seasonal rainfall coincides with the early growing period of many of the crops meaning that plots are very susceptible to erosion, especially on steep sided valleys in the region south of Lake Volta. This research investigated the processes of soil erosion by rainfall with the aim of producing a sediment yield model for a small semi-agricultural catchment in rural Ghana. Various types of modelling techniques were considered to discover those most applicable to the sub-tropical environment of Southern Ghana. Once an appropriate model had been developed and calibrated, the aim was to look at how to enable the scaling up of the model using sub-catchments to calculate sedimentation rates of Lake Volta. An experimental catchment was located in Ghana, south west of Lake Volta, where data on rainstorms and the associated streamflow, sediment loads and soil data (moisture content, classification and particle size distribution) was collected to calibrate the model. Additional data was obtained from the Soil Research Institute in Ghana to explore calibration of the Universal Soil Loss Equation (USLE, Wischmeier and Smith, 1978) for Ghanaian soils and environment. It was shown that the USLE could be successfully converted to provide meaningful soil loss estimates in the Ghanaian environment. However, due to experimental difficulties, the proposed theory and methodology of the sediment yield model could only be tested in principle. Future work may include validation of the model and subsequent scaling up to estimate sedimentation rates in Lake Volta.

Attentional shifting and the role of the dorsal pathway in visual word recognition

A substantial amount of evidence has been collected to propose an exclusive role for the dorsal visual pathway in the control of guided visual search mechanisms, specifically in the preattentive direction of spatial selection [Vidyasagar, T. R. (1999). A neuronal model of attentional spotlight: Parietal guiding the temporal. Brain Research and Reviews, 30, 66-76; Vidyasagar, T. R. (2001). From attentional gating in macaque primary visual cortex to dyslexia in humans. Progress in Brain Research, 134, 297-312]. Moreover, it has been suggested recently that the dorsal visual pathway is specifically involved in the spatial selection and sequencing required for orthographic processing in visual word recognition. In this experiment we manipulate the demands for spatial processing in a word recognition, lexical decision task by presenting target words in a normal spatial configuration, or where the constituent letters of each word are spatially shifted relative to each other. Accurate word recognition in the Shifted-words condition should demand higher spatial encoding requirements, thereby making greater demands on the dorsal visual stream. Magnetoencephalographic (MEG) neuroimaging revealed a high frequency (35-40 Hz) right posterior parietal activation consistent with dorsal stream involvement occurring between 100 and 300 ms post-stimulus onset, and then again at 200-400 ms. Moreover, this signal was stronger in the shifted word condition, compared to the normal word condition. This result provides neurophysiological evidence that the dorsal visual stream may play an important role in visual word recognition and reading. These results further provide a plausible link between early stage theories of reading, and the magnocellular-deficit theory of dyslexia, which characterises many types of reading difficulty. © 2006 Elsevier Ltd. All rights reserved.

Shifting accountability:a longitudinal qualitative study of diabetes causation accounts

We undertook a longitudinal qualitative study involving of 20 patients from Scotland who had type 2 diabetes. We looked at their perceptions and understandings of why they had developed diabetes and how, and why, their causation accounts had changed or remained stable over time. Respondents, all of whom were white, were interviewed four times over a 4-year period (at baseline, 6, 12 and 48 months). Their causation accounts often shifted, sometimes subtly, sometimes radically, over the 4 years. The experiential dimensions of living with, observing, and managing their disease over time were central to understanding the continuities and changes we observed. We also highlight how, through a process of removing, adding and/or de-emphasising explanatory factors, causation accounts could be used as “resources” to justify or enable present treatment choices. We use our work to support critiques of social cognition theories, with their emphasis upon beliefs being antecedent to behaviours. We also provide reflections upon the implications of our findings for qualitative research designs and sampling strategies.

Alzheimer's disease, a shifting paradigm in Spanish film:¿Y tú quién eres? And Amanecer de un sueño

In the last fifteen years Alzheimer's disease (AD) has changed the way in which developed countries have tended to perceive and deal with ageing. It has also become the main health problem needing to be resolved in both financial and social terms. If cancer was considered and labelled as the epidemic of the twentieth century, AD has soon been designated as the epidemic of the twenty-first century. This article analyses how AD is perceived and represented in two films, Amanecer de un sueño, directed in 2008 by Freddy Mas Franqueza, and ¿Y tú quién eres?, directed in 2007 by Antonio Mercero. As for ageing, questions of stigmatization and stereotyping around AD are discussed, and special consideration is given to the manner in which medical, social and political institutions in Spain have created a monolithic view of AD with the purpose of shaping a homogeneous social response to the disease. Current debates between those who perceive the disease as a social burden for the State and the family, and those who defend centring the discussion on the persons diagnosed with Alzheimer's disease and their personhoods frame the analysis of these two films. © W. S. Maney & Son Ltd 2013.

Reduced attentional capacity, but normal processing speed and shifting of attention in developmental dyslexia: evidence from a serial task

We report the performance of a group of adult dyslexics and matched controls in an array-matching task where two strings of either consonants or symbols are presented side by side and have to be judged to be the same or different. The arrays may differ either in the order or identity of two adjacent characters. This task does not require naming – which has been argued to be the cause of dyslexics’ difficulty in processing visual arrays – but, instead, has a strong serial component as demonstrated by the fact that, in both groups, Reaction times (RTs) increase monotonically with position of a mismatch. The dyslexics are clearly impaired in all conditions and performance in the identity conditions predicts performance across orthographic tasks even after age, performance IQ and phonology are partialled out. Moreover, the shapes of serial position curves are revealing of the underlying impairment. In the dyslexics, RTs increase with position at the same rate as in the controls (lines are parallel) ruling out reduced processing speed or difficulties in shifting attention. Instead, error rates show a catastrophic increase for positions which are either searched later or more subject to interference. These results are consistent with a reduction in the attentional capacity needed in a serial task to bind together identity and positional information. This capacity is best seen as a reduction in the number of spotlights into which attention can be split to process information at different locations rather than as a more generic reduction of resources which would also affect processing the details of single objects.

Entrepreneurship in the neighborhood:shifting patterns of economic activities in residential neighborhoods in five dutch cities

Cities are oftentimes seen as undergoing a process of "emergence" in the "new economy." However, this process has largely remained empirically underdetermined. This article examines the intra-city geography of emerging businesses in newly dominant sectors of the urban economy. The change in dominant sectors coincides with a shift towards small- and medium-sized businesses, creating new economic opportunities for urban residential areas. The residential neighborhood is introduced as a place where supply and demand side drivers operate to attract or limit such new economic activity. Allen Scott's perspective of the cognitive-cultural economy is used to analyze which neighborhoods are flourishing sites of the cognitive-cultural sectors. His perspective on industries that are on the rise in urban environments and their growth potential proves very valuable. Social demographic characteristics on the level of the neighborhood are used as predictors of the composition of the local economy. The analyses show that in particular wealthy, gentrified neighborhoods are more prone than others to becoming "hubs" of the cognitive-cultural economy. However, disadvantaged neighborhoods may under certain conditions serve as incubators for business start-ups as they offer low-rent office spaces. This has important consequences for their future economic growth potential as well as the distribution of successful businesses in the city. © 2013 Urban Affairs Association.

Shifting borders of European Union internal security:technology, externalisation and accountability

This edited volume analyzes recent key developments in EU border management. In light of the refugee crises in the Mediterranean and the responses on the part of EU member states, this volume presents an in-depth reflection on European border practices and their political, social and economic consequences. Approaching borders as concepts in flux, the authors identify three main trends: the rise of security technologies such as the EUROSUR system, the continued externalization of EU security governance such as border mission training in third states, and the unfolding dynamics of accountability. The contributions show that internal security cooperation in Europe is far from consolidated, since both political oversight mechanisms and the definition of borders remain in flux. This edited volume makes a timely and interdisciplinary contribution to the ongoing academic and political debate on the future of open borders and legitimate security governance in Europe. It offers a valuable resource for scholars in the fields of international security and migration studies, as well as for practitioners dealing with border management mechanisms.