2,488 research outputs found

    Accessibility instruments for planning practice: A review of European experiences

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    Although a large body of literature has been produced on the theoretical definitions and measurements of accessibility, the extent to which such indicators are used in planning practice is less clear. This research explores the gap between theory and application by seeking to understand what the new wave of accessibility instruments (AIs) prepared for spatial and transport planning practice purports to offer the users of AIs. Starting from the question of how urban and transport planners are designing AIs, the article analyzes and describes the AIs developed over the last decade (mainly in Europe), offering a structured overview and a clear categorization of how accessibility measures can be applied. The paper identifies AI characteristics, and considers their usability, based on AI developer perceptions

    Accessibility Instruments In Planning Practice: Bridging The Implementation Gap

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    Accessibility concepts are increasingly acknowledged as fundamental to understand cities and urban regions. Accordingly, accessibility instruments have been recognised as valuable support tools for land-use and transport planning. However, despite the relatively large number of instruments available in the literature, they are not widely used in planning practice. This paper aims to explore why accessibility instruments are not widely used in planning practice. To this end, we focus our research on perceived user-friendliness and usefulness of accessibility instruments. First, we surveyed some instrument developers, providing an overview of the characteristics of accessibility instruments available and on developers’ perceptions of their user-friendliness in planning practice. Second, we brought together developers and planning practitioners in some local workshops across Europe and Australia, where participants were asked to use insights provided by accessibility instruments for the development of planning strategies. We found that most practitioners are convinced of the usefulness of accessibility instruments in planning practice, as they generate new and relevant insights for planners. Findings suggest that not only user-friendliness problems but mainly organisational barriers and lack of institutionalisation of accessibility instruments, are the main causes of the implementation gap. Thus user-friendliness improvement may provide limited contributions to the successful implementation of accessibility concepts in planning practice. In fact, there seems to be more to gain from the active and continued engagement of instrument developers with planning practitioners and the institutionalisation of accessibility planning

    Search for radiative pumping lines of OH masers: I. The 34.6um absorption line towards 1612 MHz OH maser sources

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    The 1612 MHz hydroxyl maser in circumstellar envelopes has long been thought to be pumped by 34.6um photons. Only recently, the Infrared Space Observatory has made possible spectroscopic observations which enable the direct confirmation of this pumping mechanism in a few cases. To look for the presence of this pumping line, we have searched the Infrared Space Observatory Data Archive and found 178 spectra with data around 34.6um for 87 galactic 1612MHz masers. The analysis performed showed that the noise level and the spectral resolution of the spectra are the most important factors affecting the detection of the 34.6um absorption line. Only 5 objects from the sample (3 red supergiants and 2 galactic center sources) are found to show clear 34.6um absorption (all of them already known) while two additional objects only tentatively show this line. The 3 supergiants show similar pump rates and their masers might be purely radiatively pumped. The pump rates of OH masers in late type stars are found to be about 0.05, only 1/5 of the theoretical value of 0.25 derived by Elitzur (1992). We have also found 16 maser sources which, according to the analysis assuming Elitzur's pump rate, should show the 34.6 μ\mum absorption line but do not. These non-detections can be tentatively explained by far-infrared photon pumping, clumpy nature of the OH masing region or a limb-filling emission effect in the OH shell.Comment: 11 pages, 8 figures, 3 table

    Have a Good Trip! Expanding our Concepts of the Quality of Everyday Travelling with Flow Theory

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    The dominant tradition in transport planning and policy practice considers travel as a derived activity and travel time as an economic disutility. A growing body of literature is challenging this perspective, demonstrating that being ‘on the move’ is a rich experience interlaced with profound shared and individual meanings that can have positive implications on quality of life, well-being and personal development. Yet, mobility in general, and commuting in particular, is often reported as one of the least pleasant daily experiences and as a source of massive environmental impacts. This exploratory article hypothesizes that flow theory, based on Csikszentmihalyi´s seminal work on optimal states of consciousness, has the potential to offer important insights that can contribute to research and policy action on achieving both sustainable and satisfying forms of daily mobility. The article draws on an online exploratory questionnaire in order to reflect on flow theory in relation to the capacity of different mobility modes to either facilitate or constrain the occurrence and duration of optimal states of consciousness. Preliminary conclusions provide a basis for outlining a set of future research directions aimed at better understanding mobility experiences and their relationships with flow theory

    Geo-environmental mapping using physiographic analysis: constraints on the evaluation of land instability and groundwater pollution hazards in the Metropolitan District of Campinas, Brazil

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    Geo-environmental terrain assessments and territorial zoning are useful tools for the formulation and implementation of environmental management instruments (including policy-making, planning, and enforcement of statutory regulations). They usually involve a set of procedures and techniques for delimitation, characterisation and classification of terrain units. However, terrain assessments and zoning exercises are often costly and time-consuming, particularly when encompassing large areas, which in many cases prevent local agencies in developing countries from properly benefiting from such assessments. In the present paper, a low-cost technique based on the analysis of texture of satellite imagery was used for delimitation of terrain units. The delimited units were further analysed in two test areas situated in Southeast Brazil to provide estimates of land instability and the vulnerability of groundwater to pollution hazards. The implementation incorporated procedures for inferring the influences and potential implications of tectonic fractures and other discontinuities on ground behaviour and local groundwater flow. Terrain attributes such as degree of fracturing, bedrock lithology and weathered materials were explored as indicators of ground properties. The paper also discusses constraints on- and limitations of- the approaches taken

    Wide spectrum of NR5A1-related phenotypes in 46,XY and 46,XX individuals

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    Steroidogenic factor 1 (NR5A1, SF-1, Ad4BP) is a transcriptional regulator of genes involved in adrenal and gonadal development and function. Mutations in NR5A1 have been among the most frequently identified genetic causes of gonadal development disorders and are associated with a wide phenotypic spectrum. In 46,XY individuals, NR5A1-related phenotypes may range from disorders of sex development (DSD) to oligo/azoospermia, and in 46,XX individuals, from 46,XX ovotesticular and testicular DSD to primary ovarian insufficiency (POI). The most common 46,XY phenotype is atypical or female external genitalia with clitoromegaly, palpable gonads, and absence of Müllerian derivatives. Notably, an undervirilized external genitalia is frequently seen at birth, while spontaneous virilization may occur later, at puberty. In 46,XX individuals, NR5A1 mutations are a rare genetic cause of POI, manifesting as primary or secondary amenorrhea, infertility, hypoestrogenism, and elevated gonadotropin levels. Mothers and sisters of 46,XY DSD patients carrying heterozygous NR5A1 mutations may develop POI, and therefore require appropriate counseling. Moreover, the recurrent heterozygous p.Arg92Trp NR5A1 mutation is associated with variable degrees of testis development in 46,XX patients. A clear genotype-phenotype correlation is not seen in patients bearing NR5A1 mutations, suggesting that genetic modifiers, such as pathogenic variants in other testis/ovarian-determining genes, may contribute to the phenotypic expression. Here, we review the published literature on NR5A1-related disease, and discuss our findings at a single tertiary center in Brazil, including ten novel NR5A1 mutations identified in 46,XY DSD patients. The ever-expanding phenotypic range associated with NR5A1 variants in XY and XX individuals confirms its pivotal role in reproductive biology, and should alert clinicians to the possibility of NR5A1 defects in a variety of phenotypes presenting with gonadal dysfunction

    Re-enacting the mobility versus accessibility debate: Moving towards collaborative synergies among experts

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    The benefits of the accessibility approach in transport planning are well-known and widely documented in the literature. However, in practice, most transport planning processes are focused on improving mobility and not on improving accessibility. Recent research has made it clear that what is blocking the accessibility approach are not the technological dimensions of transport planning, or the lack of knowledge about how to perform accessibility planning in practice. This approach is being blocked instead by institutional barriers. This article critically identifies some of these barriers. Adopting a cross-disciplinary and international perspective, two rounds of in-depth interviews with accessibility experts were conducted. This allowed gathering insights not only about the institutional barriers to the adoption of the accessibility approach in transport planning practice, but also about possible pathways to make accessibility a more central concept in decision-making

    WDR5, BRCA1, and BARD1 Co-regulate the DNA Damage Response and Modulate the Mesenchymal-to-Epithelial Transition during Early Reprogramming.

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    Differentiated cells are epigenetically stable, but can be reprogrammed to pluripotency by expression of the OSKM transcription factors. Despite significant effort, relatively little is known about the cellular requirements for reprogramming and how they affect the properties of induced pluripotent stem cells. We have performed high-content screening with small interfering RNAs targeting 300 chromatin-associated factors and extracted colony-level quantitative features. This revealed five morphological phenotypes in early reprogramming, including one displaying large round colonies exhibiting an early block of reprogramming. Using RNA sequencing, we identified transcriptional changes associated with these phenotypes. Furthermore, double knockdown epistasis experiments revealed that BRCA1, BARD1, and WDR5 functionally interact and are required for the DNA damage response. In addition, the mesenchymal-to-epithelial transition is affected in Brca1, Bard1, and Wdr5 knockdowns. Our data provide a resource of chromatin-associated factors in early reprogramming and underline colony morphology as an important high-dimensional readout for reprogramming quality
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