87 research outputs found
Geometric and structural design of foldable structures
p. 2392-2404This paper initially investigates the previous works on foldable structures. Subsequently,
generation and geometric (architectural) design of compatible foldable structures with
scissor-like elements is formulated for various shapes of barrels with no geometric
limitations (free forms) for the purpose of configuration processing. Special cases for
configuration processing based on given formulation are studied to obtain different
geometries. For example, the division of the sum of the internal angles of duplets leads to
different geometries. The method employed for this division could be equal between
duplets, according to arithmetic or geometric progression, or using algebraic equations.
These methods are used to divide the sum of internal angles and radius of curvature;
Corresponding geometries are then created and compared.
The method to generate a geometry imposed by architectural requirements is also proposed in this work. Using such ordering, one can create and model free form foldable structures. To provide changeability for geometry of the structure, a special mid-connection (pivot) is proposed and a prototype model is constructed to demonstrate the efficiency. To construct real scale foldable structures, some connections and a simple method to analyze and design of this type of connections are proposed. A graph of maximum displacement vs. height of the structure is illustrated. A design-construct methodology for foldable structures is proposed.Babaei, M.; Sanaei, E. (2010). Geometric and structural design of foldable structures. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/728
Hypoxia Inducible Factor 1: A Urinary Biomarker of Kidney Disease.
Identifying noninvasive biomarkers of kidney disease is valuable for diagnostic and therapeutic purposes. Hypoxia inducible factor 1 (HIF-1) expression is known to be elevated in the kidneys in several renal disease pathologies. We hypothesized that the urinary HIF-1a mRNA level may be a suitable biomarker for expression of this protein in chronic kidney disease (CKD). We compared HIF-1a mRNA levels from urine pellets of CKD and healthy subjects. To ensure that urinary HIF-1a mRNA is of kidney origin, we examined colocalization of HIF-1a mRNA with two kidney specific markers in urine cells. We found that HIF-1a mRNA is readily quantifiable in urine pellets and its expression was significantly higher in CKD patients compared with healthy adults. We also showed that the urinary HIF-1a mRNA comes primarily from cells of renal origin. Our data suggest that urinary HIF-1a mRNA is a potential biomarker in CKD and can be noninvasively assessed in patients
The requirements and challenges in preventing of road traffic injury in Iran. A qualitative study
<p>Abstract</p> <p>Background</p> <p>Road traffic injuries (RTIs) are a major public health problem, especially in low- and middle-income countries. Among middle-income countries, Iran has one of the highest mortality rates from RTIs. Action is critical to combat this major public health problem. Stakeholders involved in RTI control are of key importance and their perceptions of barriers and facilitators are a vital source of knowledge. The aim of this study was to explore barriers to the prevention of RTIs and provide appropriate suggestions for prevention, based on the perceptions of stakeholders, victims and road-users as regards RTIs.</p> <p>Methods</p> <p>Thirty-eight semi-structured interviews were conducted with informants in the field of RTI prevention including: police officers; public health professionals; experts from the road administrators; representatives from the General Governor, the car industry, firefighters; experts from Emergency Medical Service and the Red Crescent; and some motorcyclists and car drivers as well as victims of RTIs. A qualitative approach using grounded theory method was employed to analyze the material gathered.</p> <p>Results</p> <p>The core variable was identified as "The lack of a system approach to road-user safety". The following barriers in relation to RTI prevention were identified as: human factors; transportation system; and organizational coordination. Suggestions for improvement included education (for the general public and targeted group training), more effective legislation, more rigorous law enforcement, improved engineering in road infrastructure, and an integrated organization to supervise and coordinate preventive activities.</p> <p>Conclusion</p> <p>The major barriers identified in this study were human factors and efforts to change human behaviour were suggested by means of public education campaigns and stricter law enforcement. However, the lack of a system approach to RTI prevention was also an important concern. There is an urgent need for both an integrated system to coordinate RTI activities and prevention and a major change in stakeholders' attitudes towards RTI prevention. The focus of all activities should take place on road users' safety.</p
Potency of ZnFe2O4 Nanoparticles as Corrosion Inhibitor for Stainless Steel; the Pigment Extract Study
Microalgal food supplements from the perspective of Polish consumers: patterns of use, adverse events, and beneficial effects
Tallo: A global tree allometry and crown architecture database.
This is the final version. Available from Wiley via the DOI in this record. Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research-from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non-forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo includes data for 5163 species distributed across 1453 genera and 187 plant families. The database is publicly archived under a CC-BY 4.0 licence and can be access from: https://doi.org/10.5281/zenodo.6637599. To demonstrate its value, here we present three case studies that highlight how the Tallo database can be used to address a range of theoretical and applied questions in ecology-from testing the predictions of metabolic scaling theory, to exploring the limits of tree allometric plasticity along environmental gradients and modelling global variation in maximum attainable tree height. In doing so, we provide a key resource for field ecologists, remote sensing researchers and the modelling community working together to better understand the role that trees play in regulating the terrestrial carbon cycle.Natural Environment Research Council (NERC)Natural Environment Research Council (NERC); Ministry of Education, Youth and Sports of the Czech RepublicFAPEMIGUniversidad Nacional Autónoma de MéxicoUniversidad Nacional Autónoma de MéxicoConsejo Nacional de Ciencia y TecnologíaSwedish Energy AgencyUKRIFederal Ministry of Education and ResearchNational Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaNational Science FoundationNational Science FoundationInternational Foundation for ScienceP3FACDynAfForNanjing Forestry UniversityJiangsu Science and Technology Special ProjectHebei UniversityAgence Nationale de la RechercheAgence Nationale de la RechercheAgua Salud ProjectU.S. Department of EnergyCAPE
Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU
Contains fulltext :
172380.pdf (publisher's version ) (Open Access
An improved constrained differential evolution for optimal design of steel frames with discrete variables
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