88 research outputs found
Urban streets: impact assessment and appraisal, in Better Streets for Better Cities: A Handbook for Active Street Planning, Design and Management - Chapter 9
This chapter expands on Step 6 of the street design process
(see Chapter 6), by describing the modelling and appraisal tools used in MORE and presenting some of the results from the five cities
The application of bone graft substitutes for alveolar ridge preservation after orthodontic extractions and for augmentation of residual cleft defects
The use of bone substitute materials in orthodontics is to be considered prior to
orthodontic space closure after tooth extraction during the treatment of marked
crowding as well as for treatment of residual defects in cleft-lip-and-palate children.
In both cases the common objective is structure preservation or augmentation
of the alveolar ridge. The demands to be made on the synthetic bone
graft substitute comprise not just complication-free and safe use but also the
chance of early tooth movement into the treated defect area with sufficient
stability of the new tooth position
Built Environment Determinants of Pedestrian Activities and Their Consideration in Urban Street Design
Pedestrian facilities have been regarded in urban street design as âleftover spacesâ for years, but, currently, there is a growing interest in walking and improving the quality of street environments. Designing pedestrian facilities presents the challenge of simultaneously accommodating (1) pedestrians who want to move safely and comfortably from point A to B (movement function); as well as (2) users who wish to rest, communicate, shop, eat, and enjoy life in a pleasant environment (place function). The aims of this study are to provide an overview of how the task of designing pedestrian facilities is addressed in international guidance material for urban street design, to compare this with scientific evidence on determinants of pedestrian activities, and to finally develop recommendations for advancing provisions for pedestrians. The results show that urban street design guidance is well advanced in measuring space requirements for known volumes of moving pedestrians, but less in planning pleasant street environments that encourage pedestrian movement and place activities. A stronger linkage to scientific evidence could improve guidance materials and better support urban street designers in their ambition to provide safe, comfortable and attractive street spaces that invite people to walk and to stay
Cross-site assessment of road design packages
This report develop a concept for evaluating alternative design solutions for urban streets: the Street Performance Assessment Scheme. It should be generally valid and applicable to any redesign task, to compare the performance of a road/street section: (1) with the goals formulated for each case study, (2) in situations before and after the implementation of a redesign solution, and (3) between different case studies in cross-site assessments. In this report, the Street Performance Assessment Scheme is applied to streets in five European cities. These streets have major movement and 'place' functions and have limited space availabilities, and are thus typical examples for the most challenging design tasks that urban street designers face
The manufacture of synthetic non-sintered and degradable bone grafting substitutes
A new synthetic bone grafting substitute (NanoBone®, ARTOSS GmbH, Germany)
is presented. This is produced by a new technique, the sol-gel-method. This
bone grafting substitute consists of nanocrystalline hydroxyapatite (HA) and
nanostructured silica (SiO2). By achieving a highly porous structure good osteoconductivity
can be seen. In addition, the material will be completely biodegraded
and new own bone is formed. It has been demonstrated that NanoBone® is
biodegraded by osteoclasts in a manner comparable to the natural bone remodelling
process
Bone functions and the requirements for bone grafts and substitutes in the orofacial region
Bone is the largest calcium storage, has distinctive plasticity and adaptability and
is part of the supporting tissue. An adequate composition is thus necessary. The
bone matrix consists of organic and anorganic structures. Osteoblasts, osteoclasts
and osteocytes are responsible for bone formation, resorption and metabolism.
The periosteum, endosteum and bone tissue are a functional unit and provide
protection, nutrition and growth. Bone is subject to continuous remodelling
Wound management after the application of bone grafting substitutes in the orofacial region
Surgical dressing after the application of bone grafting material depends on the
type and size of the defect. A complete and tension-free wound closure has
proved to be successful. In this context the infection problem needs special
attention. Bone graft substitutes with an adequate surface structure, porosity
and chemical properties, in combination with sufficient blood circulation, hold
osteoconductive potential. They serve as a guide rail for the osteoblast-induced
formation of new bone tissue, which at best may lead to complete replacement
of the grafting material
Critical considerations on the diagnostic appraisal, adaptation and remodelling of bone graft substitutes
The diagnostic assessment of skeletal defects has a long-standing tradition. As
a result of the development of new bone grafting materials, the demands on
diagnostic assessment have also increased. The mode and quality of diagnostic
appraisal are crucial to further clinical use and outcome prediction. Alongside
traditional clinical and biological techniques, molecular biological methods have
gained a broad scope of application and will be used even more frequently in
the future
Mathematical modeling of cell population dynamics in the colonic crypt and in colorectal cancer
Colorectal cancer is initiated in colonic crypts. A succession of genetic mutations or epigenetic changes can lead to homeostasis in the crypt being overcome, and subsequent unbounded growth. We consider the dynamics of a single colorectal crypt by using a compartmental approach [Tomlinson IPM, Bodmer WF (1995) Proc Natl Acad Sci USA 92: 11130-11134], which accounts for populations of stem cells, differential cells, and transit cells. That original model made the simplifying assumptions that each cell popuation divides synchronously, but we relax these assumptions by adopting an age-structured approach that models asynchronous cell division, and by using a continuum model. We discuss two mechanims that could regulate the growth of cell numbers and maintain the equilibrium that is normally observed in the crypt. The first will always maintain an equilibrium for all parameter values, whereas the second can allow unbounded proliferation if the net per capita growth rates are large enough. Results show that an increase in cell renewal, which is equivalent to a failure of programmed cell death or of differentiation, can lead to the growth of cancers. The second model can be used to explain the long lag phases in tumor growth, during which news, higher equilibria are reached, before unlimited growth in cell number ensues
Urban mobility: preparing for the future, learning from the past - CREATE project summary and recommendations
Transport decisions, and their resulting impacts on land use patterns, fundamentally shape and define a city, both physically and through the daily living patterns of its citizens and visitors. As policy priorities change, so do the types of measures that are introduced, with resulting shifts in travel behaviour and lifestyles. What at one point in a cityâs history is often seen as the âinevitableâ need to adapt the urban fabric to accommodate the growing use of the motor car, may later be replaced by a focus on people movement and sustainable mobility, and a growing interest in urban quality and vitality â a city of places for people. CREATE (Congestion Reduction in Europe: Advancing Transport Efficiency) charts these changes in policy priorities and travel behaviour through the experiences of five Western European capital cities over the last 50 years, noting the policy tensions and competing city visions, the triggers leading to change and the evolving governance arrangements that have facilitated, or sometimes retarded, such developments. As policy priorities change, so do measures of success; in a car-focused city congestion is the dominant concern, but this becomes less important as more people travel by rail or on foot or by cycle, and when cities put a greater value on high quality places. Alongside this there have been technical changes, in the types of methods used to model behaviour and appraise schemes, and in the ways in which these tools are used. This document provides an introduction to the CREATE project, focusing on findings and lessons of value to practitioners, and those developing or updating their Sustainable Urban Mobility Plans. It is underpinned by extensive qualitative and quantitative research, which is fully documented in several deliverables, and summarised in a series of Technical Notes. A more comprehensive set of Guidelines is also available
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