Stepping accuracy and visuomotor control among older adults : effect of target contrast and refractive blur

Purpose: Older adults have increased visual impairment, including refractive blur from presbyopic multifocal spectacle corrections, and are less able to extract visual information from the environment to plan and execute appropriate stepping actions; these factors may collectively contribute to their higher risk of falls. The aim of this study was to examine the effect of refractive blur and target visibility on the stepping accuracy and visuomotor stepping strategies of older adults during a precision stepping task. Methods: Ten healthy, visually normal older adults (mean age 69.4 ± 5.2 years) walked up and down a 20 m indoor corridor stepping onto selected high and low-contrast targets while viewing under three visual conditions: best-corrected vision, +2.00 DS and +3.00 DS blur; the order of blur conditions was randomised between participants. Stepping accuracy and gaze behaviours were recorded using an eyetracker and a secondary hand-held camera. Results: Older adults made significantly more stepping errors with increasing levels of blur, particularly exhibiting under-stepping (stepping more posteriorly) onto the targets (p<0.05), while visuomotor stepping strategies did not significantly alter. Stepping errors were also significantly greater for the low compared to the high contrast targets and differences in visuomotor stepping strategies were found, including increased duration of gaze and increased interval between gaze onset and initiation of the leg swing when stepping onto the low contrast targets. Conclusions: These findings highlight that stepping accuracy is reduced for low visibility targets, and for high levels of refractive blur at levels typically present in multifocal spectacle corrections, despite significant changes in some of the visuomotor stepping strategies. These findings highlight the importance of maximising the contrast of objects in the environment, and may help explain why older adults wearing multifocal spectacle corrections exhibit an increased risk of falling.

Adverse weather effects on bus ridership

This study focuses on weather effects on daily bus ridership in Brisbane, given bus’ dominance in this city. The weather pattern of Brisbane varies by season according to its sub-tropical climate characteristics. Bus is prone to inclement weather condition as it shares the road system with general traffic. Moreover, bus stops generally offer less or sometimes no protection from adverse weather. Hence, adverse weather conditions such as rain are conjectured to directly impact on daily travel behaviour patterns. There has been limited Australian research on the impact of weather on daily transit ridership. This study investigates the relationship between rainy day and daily bus ridership for the period of 2010 to 2012. Overall, rainfall affects negatively with varying impacts on different transit groups. However, this analysis confirmed a positive relationship between consecutive rainy days (rain continuing for 3 or more days). A possible explanation could be that people may switch their transport mode to bus to avoid high traffic congestion and higher accident potentiality on rainy days. Also, Brisbane’s segregated busway (BRT) corridor works favourably towards this mode choice. Our study findings enhance the fundamental understanding of traveller behaviour, particularly mode choice behaviour under adverse weather conditions.

How to plan and implement an environmental education program for a conservation area : lessons from Australia and Borneo

The Augo Wetland Forest Park, along with other conservation areas around the world, provides an opportunity for a personal connection with the natural world - an opportunity for creating ways to convince people to reverse the degradation of the planet. In this presentation I use the settings approach, as used by the World Health Organisation in health promotion, as a framework. The WHO’s 1986 Ottawa Charter states that "Health is created and lived by people within the settings of their everyday life; where they learn, work, play, and love." I argue that, similarly, a conservation area provides a setting for people to connect with environmental issues and can be the place where positive behaviours and actions for the environment are created and enacted. In a wired and virtual world, such settings may be the only opportunity some people, especially children, get to connect with the environment. An evidence-based, intentionally designed and implemented environmental education program enhances the opportunities for the personal connection and subsequent action. Planning and implementing an Environmental education program for a conservation area requires an understanding of the principles of three domains: • Environmental Communication • Environmental Education • Environmental Interpretation In this presentation I define these domains and demonstrate how they become interdependent within the context of a particular setting such as a conservation area. I outline the principles of each domain and demonstrate how they can be enacted with reference to environmental education program case studies from settings in Australia and Borneo. The first case study is based around a proposal for a planned residential community at Eden’s Crossing, in Brisbane’s high growth Western corridor. The setting featured a number of important natural and heritage conservation characteristics and the developer wanted to be pro-active in informing the market what this development aims to achieve in terms of innovative community and environmental objectives. By designing an education and interpretation program in line with best practice education and interpretation principles the developers would be assisted in their efforts to build community, preserve heritage, and facilitate environmentally sensitive lifestyles for the future residents of Eden’s Crossing. Above all, the strategy focused on advancing sustainability in a way that made the Eden’s Crossing greenfield development significantly greener. It did this by interacting with prospective purchasers, and building knowledge about sustainability with a view to shaping the future community of Eden’s Crossing in terms of attitudes and behaviours. The second case study is based around the development of the Rainforest Interpretation Centre (RIC), now renamed the Rainforest Discovery Centre, an environmental education facility managed by the Sabah Forestry Department (SFD) and located at the edge of the Kabili-Sepilok Forest Reserve in the East Malaysian state of Sabah (Borneo). This setting is of paramount importance for biodiversity conservation and research and a vital habitat for orang utan. As an Environmental Education Consultant I was tasked with developing an environmental education program for this setting as part of the SFD’s long- term strategy towards sustainable forest management. By employing the principles of Environmental Education and Environmental Interpretation I designed and implemented a program with three major components: • an environmental education component for visiting primary and secondary school groups. • an environmental education component for in-service and pre-service teachers and teacher educators. • a public awareness and environmental interpretation component which caters for the general public and tourists. From these modest beginnings the program has expanded and new facilities have been developed to meet the demands of visitors, teachers and students. The effectiveness of the program can be traced back to the grounding in the principles of best practice environmental education, communication and interpretation.

Empirical modelling of the relationship between bus and car speeds on signalised urban networks

Vehicle speed is an important attribute for analysing the utility of a transport mode. The speed relationship between multiple modes of transport is of interest to traffic planners and operators. This paper quantifies the relationship between bus speed and average car speed by integrating Bluetooth data and Transit Signal Priority data from the urban network in Brisbane, Australia. The method proposed in this paper is the first of its kind to relate bus speed and average car speed by integrating multi-source traffic data in a corridor-based method. Three transferable regression models relating not-in-service bus, in-service bus during peak periods, and in-service bus during off-peak periods with average car speed are proposed. The models are cross-validated and the interrelationships are significant.

Adverse weather effects on bus ridership

This study focuses on the effects of weather on daily bus ridership in Brisbane, given the dominance of buses in that city. The weather pattern of Brisbane varies by season according to its subtropical climate characteristics. Bus operation is affected by inclement weather conditions, as buses share the road system with general traffic. Moreover, bus stops generally offer little, or sometimes no, protection from adverse weather. Hence, adverse weather conditions such as rain are thought to directly impact on daily travel behaviour patterns. There has been limited Australian research on the impact of weather on daily transit ridership. This study investigates the relationship between rainy days and daily bus ridership for the period 2010 to 2012. Overall, rainfall has a negative effect, with varying impacts on different transit groups. However, this analysis confirmed a positive relationship between consecutive rainy days (rain continuing for 3 or more days). A possible explanation could be that people switch their transport mode to bus to avoid high traffic congestion and higher accident potentiality on rainy days. Also, Brisbane’s segregated busway corridor works favourably towards this mode choice. The findings of our study enhance the fundamental understanding of traveller behaviour, particularly mode-choice behaviour, under adverse weather conditions.

Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks in 188 countries, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013

Background The Global Burden of Disease, Injuries, and Risk Factor study 2013 (GBD 2013) is the first of a series of annual updates of the GBD. Risk factor quantification, particularly of modifiable risk factors, can help to identify emerging threats to population health and opportunities for prevention. The GBD 2013 provides a timely opportunity to update the comparative risk assessment with new data for exposure, relative risks, and evidence on the appropriate counterfactual risk distribution. Methods Attributable deaths, years of life lost, years lived with disability, and disability-adjusted life-years (DALYs) have been estimated for 79 risks or clusters of risks using the GBD 2010 methods. Risk–outcome pairs meeting explicit evidence criteria were assessed for 188 countries for the period 1990–2013 by age and sex using three inputs: risk exposure, relative risks, and the theoretical minimum risk exposure level (TMREL). Risks are organised into a hierarchy with blocks of behavioural, environmental and occupational, and metabolic risks at the first level of the hierarchy. The next level in the hierarchy includes nine clusters of related risks and two individual risks, with more detail provided at levels 3 and 4 of the hierarchy. Compared with GBD 2010, six new risk factors have been added: handwashing practices, occupational exposure to trichloroethylene, childhood wasting, childhood stunting, unsafe sex, and low glomerular filtration rate. For most risks, data for exposure were synthesised with a Bayesian meta-regression method, DisMod-MR 2.0, or spatial-temporal Gaussian process regression. Relative risks were based on meta-regressions of published cohort and intervention studies. Attributable burden for clusters of risks and all risks combined took into account evidence on the mediation of some risks such as high body-mass index (BMI) through other risks such as high systolic blood pressure and high cholesterol. Findings All risks combined account for 57·2% (95% uncertainty interval [UI] 55·8–58·5) of deaths and 41·6% (40·1–43·0) of DALYs. Risks quantified account for 87·9% (86·5–89·3) of cardiovascular disease DALYs, ranging to a low of 0% for neonatal disorders and neglected tropical diseases and malaria. In terms of global DALYs in 2013, six risks or clusters of risks each caused more than 5% of DALYs: dietary risks accounting for 11·3 million deaths and 241·4 million DALYs, high systolic blood pressure for 10·4 million deaths and 208·1 million DALYs, child and maternal malnutrition for 1·7 million deaths and 176·9 million DALYs, tobacco smoke for 6·1 million deaths and 143·5 million DALYs, air pollution for 5·5 million deaths and 141·5 million DALYs, and high BMI for 4·4 million deaths and 134·0 million DALYs. Risk factor patterns vary across regions and countries and with time. In sub-Saharan Africa, the leading risk factors are child and maternal malnutrition, unsafe sex, and unsafe water, sanitation, and handwashing. In women, in nearly all countries in the Americas, north Africa, and the Middle East, and in many other high-income countries, high BMI is the leading risk factor, with high systolic blood pressure as the leading risk in most of Central and Eastern Europe and south and east Asia. For men, high systolic blood pressure or tobacco use are the leading risks in nearly all high-income countries, in north Africa and the Middle East, Europe, and Asia. For men and women, unsafe sex is the leading risk in a corridor from Kenya to South Africa. Interpretation Behavioural, environmental and occupational, and metabolic risks can explain half of global mortality and more than one-third of global DALYs providing many opportunities for prevention. Of the larger risks, the attributable burden of high BMI has increased in the past 23 years. In view of the prominence of behavioural risk factors, behavioural and social science research on interventions for these risks should be strengthened. Many prevention and primary care policy options are available now to act on key risks.

A Nonlinear Approach for Re-entry Guidance of Reusable Launch Vehicles Using Model Predictive Static Programming

A nonlinear suboptimal guidance scheme is developed for the reentry phase of the reusable launch vehicles. A recently developed methodology, named as model predictive static programming (MPSP), is implemented which combines the philosophies of nonlinear model predictive control theory and approximate dynamic programming. This technique provides a finite time nonlinear suboptimal guidance law which leads to a rapid solution of the guidance history update. It does not have to suffer from computational difficulties and can be implemented online. The system dynamics is propagated through the flight corridor to the end of the reentry phase considering energy as independent variable and angle of attack as the active control variable. All the terminal constraints are satisfied. Among the path constraints, the normal load is found to be very constrictive. Hence, an extra effort has been made to keep the normal load within a specified limit and monitoring its sensitivity to the perturbation.

Suboptimal reentry guidance of a reusable launch vehicle using pitch plane maneuver

Using the recently developed model predictive static programming (MPSP) technique, a nonlinear suboptimal reentry guidance scheme is presented in this paper for a reusable launch vehicle (RLV). Unlike traditional RLV guidance, the problem considered over here is restricted only to pitch plane maneuver of the vehicle, which allows simpler mission planning and vehicle load management. The computationally efficient MPSP technique brings in the philosophy of trajectory optimization into the framework of guidance design, which in turn results in very effective guidance schemes in general. In the problem addressed in this paper, it successfully guides the RLV through the critical reentry phase both by constraining it to the allowable narrow flight corridor as well as by meeting the terminal constraints at the end of the reentry segment. The guidance design is validated by considering possible aerodynamic uncertainties as well as dispersions in the initial conditions. (C) 2010 Elsevier Masson SAS. All rights reserved.

'South-South' Remittance - Poverty reduction nexus. The Case of 'Hadiya' immigrants in South Africa, as Agents of 'Constituence development' in Ethiopia, and the policy implications of their 'remittance instrument'

This thesis explores the link between South-South remittance and development. It attempts to establish improved understanding about the role of immigrants as agents of constituency growth and development. By doing so, it illuminates the dark corners of the policy implications that the unconventional development agency of immigrants might have for countries in the Organization ft Economic Cooperation and Development (OECD). The thesis problematises the existence of state-centric international cooperation as providing the recipe for failed Aid in the face of global poverty menace. In the last half a century, the relative shi' of focus to non-state actors brought about the proliferation of NGOs. That, intrun, helped improve international access to crisis situations; however, their long-term remedial impacts on poverty and development have been contested. Major misgivings for non-governmental organizations (NGOs) are, on one hand, low level goal-bound expenditures and lack of independence from influence of the state, on the other. Therefore, the thesis enterprises to empirically verify its fundamental question whether remitting immigrants constitute an alternative development agency to the traditional players: the State and NGOs. Its main arguments are: due to state's failures in bringing sustainable development in many countries of the South, the future of poverty reduction and development also rests in immigrants' remittances. Nonetheless, in the last decade, remittance security-nexus dominated its discourse. Because of that remittance was viewed as something requiring global regime and restrictions. These temptations to tightly regulate remittance flows carry the danger of overlooking its trans-boundary nature and its strong link with livelihood of the poor. Therefore, to avoid unintended consequences of interventions, there need to be clear policy that bases itself on a discursive knowledge on the issues of North-South and South-South remittances The study involved both literature based and empirical research. It employed Discourse Analysis (C as main method for the former and snow-balling as its approach for the latter. For the first part the thesis constructed three conceptual models, these are: metrological model, police model and ecological model on remittance development-nexus. Through this modeling, the thesis achieved better deconstruction on the concepts remittance, immigrants and development agency. The protagonists of each model, the values and interests they represent, and their main arguments along various lines of dichotomies have been discussed. For instance, the main treats of meteorological model include: it sees remittance as transitional economic variable which require constant speculations and global management; it acts as meteorological station for following up or predicting the level, direction, flow and movement of global remittance. It focuses on official lines and considers the state as legitimate recipient of advic and positive consequence of remittance. On the other hand, police model views remittance as beir at best, development neutral or as an illicit activity requiring global regulations and tight control. Both immigrants and remittance viewed as subversive to establishments. It gives primacy to state stable agent of development and a partner for international cooperation. The anti-thesis to the police model is supplied by ecological model, which this thesis is a part. Ecological model on remittance and immigrants argues that, tight global regulations alone cannot be a panacea for possible abuse of informal remittance system. Ecological model, not only links remittance to poverty reduction, the main trust of development, but also considers the development agency of immigrants as critical factor for 21st century north-south development intervention. It sees immigrants as development conscious and their remittance instrument as most stable flow of finance to the developing countries. Besides, it sees remittance as effective poverty solutions than Foreign Direct Investment and international AID. This thesis focuses on the significance of South-South remittance and investigates the South Africa - Ethiopia remittance corridor, as case study; and empirically verifies the role of Ethiopian (Kembata and Hadiya) immigrants in South Africa as agents of local development back home. The study involved techniques of interview, group discussions, observations and investigative study. It also looked into the determinants of their migration to South Africa, and their remittance to Ethiopia. The theoretical models in the first part of the thesis have been operationalised throughout the empirical part to verify if the Kembata and Hadiya immigrants played the crucial role in their household poverty and local development in comparison with the Ethiopian state and the NGOs involved in the system. As evidenced by the research the thesis has made three distinct contributions to the discourse of remittance development-nexus. Fist, it systematized the debate about linkages between remittance, immigrants, development agency and policy of international cooperation by creating three conceptual models (school of thoughts); second, it singled out remitting immigrants as new agents of development in the South; third, it deconstructed concept of remittance and established South¬South remittance as additional sphere of academic investigation. In addition to the above contributions, the thesis finds that Kembata and Hadiya immigrants have engaged in various developmental activities in their locality than usually anticipated. Hence, it concludes that Ethiopian immigrants constitute an alternative development agency to the state and other non-state actors in their country, and the lesson can be applied to poverty reduction strategies in most developing countries.

Revisiting the earthquake sources in the Himalaya: Perspectives on past seismicity

The similar to 2500 km-long Himalaya plate boundary experienced three great earthquakes during the past century, but none of them generated any surface rupture. The segments between the 1905-1934 and the 1897-1950 sources, known as the central and Assam seismic gaps respectively, have long been considered holding potential for future great earthquakes. This paper addresses two issues concerning earthquakes along the Himalaya plate boundary. One, the absence of surface rupture associated with the great earthquakes, vis-a-vis the purported large slip observed from paleoseismological investigations and two, the current understanding of the status of the seismic gaps in the Central Himalaya and Assam, in view of the paleoseismological and historical data being gathered. We suggest that the ruptures of earthquakes nucleating on the basal detachment are likely to be restricted by the crustal ramps and thus generate no surface ruptures, whereas those originating on the faults within the wedges promote upward propagation of rupture and displacement, as observed during the 2005 Kashmir earthquake, that showed a peak offset of 7 m. The occasional reactivation of these thrust systems within the duplex zone may also be responsible for the observed temporal and spatial clustering of earthquakes in the Himalaya. Observations presented in this paper suggest that the last major earthquake in the Central Himalaya occurred during AD 1119-1292, rather than in 1505, as suggested in some previous studies and thus the gap in the plate boundary events is real. As for the Northwestern Himalaya, seismically generated sedimentary features identified in the 1950 source region are generally younger than AD 1400 and evidence for older events is sketchy. The 1897 Shillong earthquake is not a decollement event and its predecessor is probably similar to 1000 years old. Compared to the Central Himalaya, the Assam Gap is a corridor of low seismicity between two tectonically independent seismogenic source zones that cannot be considered as a seismic gap in the conventional sense. (C) 2011 Elsevier B.V. All rights reserved.

Reinforcement learning with average cost for adaptive control of traffic lights at intersections

We propose for the first time two reinforcement learning algorithms with function approximation for average cost adaptive control of traffic lights. One of these algorithms is a version of Q-learning with function approximation while the other is a policy gradient actor-critic algorithm that incorporates multi-timescale stochastic approximation. We show performance comparisons on various network settings of these algorithms with a range of fixed timing algorithms, as well as a Q-learning algorithm with full state representation that we also implement. We observe that whereas (as expected) on a two-junction corridor, the full state representation algorithm shows the best results, this algorithm is not implementable on larger road networks. The algorithm PG-AC-TLC that we propose is seen to show the best overall performance.

Identificación de habitats potenciales, efectivos y conectividad para la fauna silvestre, Nandaime, Nicaragua

El presente estudio surge a partir de monitoreos previos en la zona en los cuales se determinaron muy pocas especies principalmente de Mamíferos, así que se propuso conocer si los hábitats en el parche tiene la capacidad para albergar suficientes especies y si el parche se encontraba aislado de otros para que se diera un flujo de animales desde otras partes del paisaje hasta el sitio de interés. Se identificaron los hábitats efectivos y potenciales y la existencia de conexión de ésta área con otra área natural (estudio de paisaje) que sirva de corredor a la fauna silvestre en la comunidad La Chipopa, Nandaime. Los tipos de hábitats se seleccionaron según criterios florísticos: formas de vida predominantes, composición y densidad de especies. Para el estudio de conectividad y fragmentación se realizó un análisis con imágenes de satélite para determinar las clases de cobertura de la zona y se utilizaron como firmas espectrales las clases de cobertura vegetal 2011 del Ministerio de Agropecuario y Forestal (MAGFOR), la herramienta V_LATE 1.1 y la herramienta Corridor Designer . Se determinaron siete tipos de hábitat. El hábitat de mayor tamaño fue el Área de árboles con poca lianas (AAPL) (3.25 ha) la cual representa el 76 % del área total. En registro bibliográfico se determinaron 270 especies en el paisaje, de éstas el 22 % no encontrarían hábitat dentro del área. El hábitat efectivo el cual alberga más especies (12 ) fue AAPL. Dentro de los hábitats potenciales se encuentran: AAP L (25 ) y Área de árboles con mucha infección por lianas (AAML) (12 ), sin embargo, se determinaron que 67 especies (32 %) prefieren cualquier hábitat como potencial dentro del mosaico. El análisis de estructura del paisaje indica que el área se divide en 17 clases de cobertura, de éstas, las áreas de tacotal cubren el 48% del total mientras que las áreas de cultivos y pastos cubren en 34%. Dentro de la matriz del paisaje el uso que se encuentra más fragmentado es el área de bosque cerrado ya que la distancia mínima que una especie debería de recorrer para encontrar esa clase es de 4,184 m, las clases de cobertura menos fragmentadas fueron las áreas agrícolas y pastos. Existe una relación entre los índices de diversidad de formas , dimensión fractal y proximidad en relación a los usos cultivos, pasto y bosque latifoliado cerrado. Dentro del paisaje se crean dos tipos de corredores uno se localiza al noroeste y otro al sureste, a pesar de formarse corredores el paisaje se encuentra muy fragmentado para permitir la conectividad de Nandarola con otros parches cercanos.

Identificación de habitats potenciales, efectivos y conectividad para la fauna silvestre, Nandaime, Nicaragua

El presente estudio se propone determinar los hábitats efectivos y potenciales dentro de un parche de bosque seco secundario de 4.26 ha y la existencia de conexión de ésta área con otra área natural (estudio de paisaje) que sirva de corredor a la fauna silvestre en la comunidad La Chipopa, Nandaime. Los tipos de hábitats se seleccionaron según criterios florísticos. Para el estudio de conectividad y fragmentación se realizó un análisis con imágenes de satélite para determinar las clases de cobertura de la zona y se utilizaron como firmas espectrales las clases de cobertura vegetal 2011 del Ministerio de Agropecuario y Forestal (MAGFOR), la herramienta V_LATE 1.1 y la herramienta corridor desinger. Se determinaron siete tipos de hábitat. El hábitat de mayor tamaño fue el Área de árboles con poca infección con lianas (AAPL) (3.05 ha) la cual representa el 72 % del área total. En registro bibliográfico se determinaron 271 especies en el paisaje, de éstas, 102 (38 %) no encontrarían hábitat dentro del área. Los hábitats efectivos se determinaron por medio de muestreos anteriores, la mayor cantidad de especies (11 o el 33%) se asocia con AAPL. Dentro de los hábitats potenciales se encuentran: AAPL (23 o el 17 %) y Área de árboles con mucha infección por lianas (AAML) (12 o el 9%), sin embargo se determinaron que 26 especies (19%) prefieren toda el área como hábitat potencial. El análisis de estructura del paisaje indica que el área se divide en 17 clases de cobertura, de éstas, las áreas de tacotal cubren el 48% del total mientras que las áreas de cultivos y pastos cubren en 34%. Dentro de la matriz del paisaje el uso que se encuentra más fragmentado es el área de bosque cerrado ya que la distancia mínima que una especie de fauna silvestre debería de recorrer para encontrar esa clase es de 4,184 m, las clases de cobertura menos fragmentadas fueron las áreas agrícolas y pastos. Existe una relación entre las variables forma, dimensión fractal y proximidad en relación a los usos cultivos, pasto y bosque latifoliado cerrado. El paisaje se encuentra muy fragmentado para permitir la existencia de corredores por donde fluya la fauna silvestre.

[A_Villabuena_Montecillo] Documentación geométrica del dolmen de El Montecillo (Villabuena de Álava)

[ES] Tumba megalítica compuesta por 8 losas (6 en la cámara, una de ellas caída originalmente y 2 en el corredor). El tamaño de la cámara es de unos 2 x 2,5 metros que se encuentra en un morcuero de unos 10 metros de diámetro.

[R_Logroño_Muralla] Documentación geométrica del Cubo del Revellín (Logroño, La Rioja)

[ES] Documentación del exterior y del interior del cubo de la muralla de Logroño. Esta torre tiene una forma aproximadamente cilíndrica de 10 metros de radio. Al interior se compone de dos niveles, el superior (antiguo teatro) que forma una estancia circular con un pilar en el centro y el inferior que consiste en una estancia abovedada. Además se ha documentado una galería de acceso.