bluuebunny/crossref_metadata_2025 huggingface dataset:
Testosterone and risk of breast cancer: appraisal of existing evidence
Authors: Traish Abdulmaged M. , Fetten Katharina , Miner Martin , Hansen Michael L. , Guay Andre
Published: May 2010

The objective of this review was to examine data from preclinical, clinical and epidemiological studies to evaluate if testosterone (T) poses increased risk of breast cancer in women. Appraisal of the existing literature produced several lines of evidence arguing against increased breast cancer risk with T. These include: (i) Data from breast tumor cell lines treated with androgens did not corroborate the notion that T increases breast cancer risk. On the contrary, androgens appear to be protective, as they inhibit tumor cell growth. (ii) Many of the epidemiological studies claiming an association between T and breast cancer did not adjust for estrogen levels. Studies adjusted for estrogen levels reported no association between T and breast cancer. (iii) Data from clinical studies with exogenous androgen treatment of women with endocrine and sexual disorders did not show any increase in incidence of breast cancer. (iv) Women afflicted with polycystic ovary disease, who exhibit high levels of androgens do not show increased risk of breast cancer compared to the general population. (v) Female to male transsexuals, who receive supraphysiological doses of T for long time periods prior to surgical procedures, do not report increased risk of breast cancer. (vi) Finally, women with hormone responsive primary breast cancer are treated with aromatase inhibitors, which block conversion of androgens to estrogens, thus elevating androgen levels. These women do not experience increased incidence of contralateral breast cancer nor do they experience increased tumor growth. In conclusion, the evidence available strongly suggests that T does not increase breast cancer risk in women.
Spatial Deformation Measurement Using Transparent Soil
Authors: Iskander Magued , Liu Jinyuan
Published: May 2010

This paper addresses the need for nonintrusively measuring spatial deformation pattern inside soils. In this study, transparent soil surrogates are used in model tests instead of natural soils. Transparent soil with macrogeotechnical properties similar to those of natural soils was made of either transparent amorphous silica gels or powders and a pore fluid with a matching refractive index. An optical system consisting of a laser light, a line-generator lens, a charge-coupled device (CCD) camera, a frame grabber, and a computer was developed to optically slice a transparent soil model. A distinctive speckle pattern is generated by the interaction of the laser light and transparent soil. The laser speckle images before and after deformation were used to nonintrusively measure the relative displacement field using digital image cross-correlation. Spatial displacement fields under a model footing were obtained by combining several cross-sections in MATLAB®. Test results showed that the developed optical system and transparent soil are suitable for studying soil-structural interaction problems.
Identification of Selection Signatures in Cattle Breeds Selected for Dairy Production
Authors: Stella Alessandra , Ajmone-Marsan Paolo , Lazzari Barbara , Boettcher Paul
Published: May 2010

The genomics revolution has spurred the undertaking of HapMap studies of numerous species, allowing for population genomics to increase the understanding of how selection has created genetic differences between subspecies populations. The objectives of this study were to (1) develop an approach to detect signatures of selection in subsets of phenotypically similar breeds of livestock by comparing single nucleotide polymorphism (SNP) diversity between the subset and a larger population, (2) verify this method in breeds selected for simply inherited traits, and (3) apply this method to the dairy breeds in the International Bovine HapMap (IBHM) study. The data consisted of genotypes for 32,689 SNPs of 497 animals from 19 breeds. For a given subset of breeds, the test statistic was the parametric composite log likelihood (CLL) of the differences in allelic frequencies between the subset and the IBHM for a sliding window of SNPs. The null distribution was obtained by calculating CLL for 50,000 random subsets (per chromosome) of individuals. The validity of this approach was confirmed by obtaining extremely large CLLs at the sites of causative variation for polled (BTA1) and black-coat-color (BTA18) phenotypes. Across the 30 bovine chromosomes, 699 putative selection signatures were detected. The largest CLL was on BTA6 and corresponded to KIT, which is responsible for the piebald phenotype present in four of the five dairy breeds. Potassium channel-related genes were at the site of the largest CLL on three chromosomes (BTA14, -16, and -25) whereas integrins (BTA18 and -19) and serine/arginine rich splicing factors (BTA20 and -23) each had the largest CLL on two chromosomes. On the basis of the results of this study, the application of population genomics to farm animals seems quite promising. Comparisons between breed groups have the potential to identify genomic regions influencing complex traits with no need for complex equipment and the collection of extensive phenotypic records and can contribute to the identification of candidate genes and to the understanding of the biological mechanisms controlling complex traits.
Evolution of a Distinct Genomic Domain in Drosophila: Comparative Analysis of the Dot Chromosome in Drosophila melanogaster and Drosophila virilis
Authors: Leung Wilson , Shaffer Christopher D , Cordonnier Taylor , Wong Jeannette , Itano Michelle S , Slawson Tempel Elizabeth E , Kellmann Elmer , Desruisseau David Michael , Cain Carolyn , Carrasquillo Robert , Chusak Tien M , Falkowska Katazyna , Grim Kelli D , Guan Rui , Honeybourne Jacquelyn , Khan Sana , Lo Louis , McGaha Rebecca , Plunkett Jevon , Richner Justin M , Richt Ryan , Sabin Leah , Shah Anita , Sharma Anushree , Singhal Sonal , Song Fine , Swope Christopher , Wilen Craig B , Buhler Jeremy , Mardis Elaine R , Elgin Sarah C R
Published: May 2010

The distal arm of the fourth (“dot”) chromosome of Drosophila melanogaster is unusual in that it exhibits an amalgamation of heterochromatic properties (e.g., dense packaging, late replication) and euchromatic properties (e.g., gene density similar to euchromatic domains, replication during polytenization). To examine the evolution of this unusual domain, we undertook a comparative study by generating high-quality sequence data and manually curating gene models for the dot chromosome of D. virilis (Tucson strain 15010–1051.88). Our analysis shows that the dot chromosomes of D. melanogaster and D. virilis have higher repeat density, larger gene size, lower codon bias, and a higher rate of gene rearrangement compared to a reference euchromatic domain. Analysis of eight “wanderer” genes (present in a euchromatic chromosome arm in one species and on the dot chromosome in the other) shows that their characteristics are similar to other genes in the same domain, which suggests that these characteristics are features of the domain and are not required for these genes to function. Comparison of this strain of D. virilis with the strain sequenced by the Drosophila 12 Genomes Consortium (Tucson strain 15010–1051.87) indicates that most genes on the dot are under weak purifying selection. Collectively, despite the heterochromatin-like properties of this domain, genes on the dot evolve to maintain function while being responsive to changes in their local environment.
Paraquat Ingestion: A Challenging Diagnosis
Authors: Chen Jerome G. , Eldridge David L. , Lodeserto Frank J. , Ming David Y. , Turner Kristen M. , Vanderford Joel L. , Sporn Thomas A. , Schulman Scott R.
Published: May 2010

Paraquat is an herbicide that is highly toxic to humans. Pediatric ingestion has become uncommon in the United States because of preventative efforts. We report here an unintentional, fatal paraquat ingestion by an 8-year-old child. Storage in an inappropriate container, confusion between herbicide trade names, nonspecific symptoms, and a delay in follow-up produced challenges in the diagnosis. In the absence of a clear history of ingestion, paraquat poisoning should be suspected in children who develop skin and mucous membrane burns, gastrointestinal symptoms, acute kidney injury, and respiratory failure.
Infant With Probable Catastrophic Antiphospholipid Syndrome Successfully Managed With Rituximab
Authors: Iglesias-Jiménez Estibaliz , Camacho-Lovillo Marisol , Falcón-Neyra Dolores , Lirola-Cruz Jose , Neth Olaf
Published: May 2010

The antiphospholipid syndrome (APS) is an acquired thrombophilic disorder characterized by the presence of autoantibodies to a variety of phospholipids and phospholipid-binding proteins. Clinical manifestations range from being asymptomatic to having imminently life-threatening events. Catastrophic antiphospholipid syndrome (CAPS) occurs in <1% of patients with APS and is defined by multiple small-vessel occlusions that lead to multiple-organ failure and is associated with high morbidity and mortality rates. Here we report the case of a 3-month-old boy with probable CAPS who presented to us with digital necrosis and pulmonary hemorrhage. In addition, a skin biopsy demonstrated multiple small-vessel thromboses without signs of vasculitis. Results of testing for autoantibodies were positive for anti-β2 glycoprotein I (anti-β2-GPI) only. His treatment consisted of high-dose steroids, immunoglobulin therapy, exchange transfusion, cyclophosphamide, and rituximab as well as iloprost and bosentan as vasodilators for his ischemia; he showed an excellent clinical response. To the best of our knowledge, this is the youngest patient with probable CAPS, the first reported patient to test positive for anti-β2-GPI antibodies and negative for anticardiolipin antibodies and lupus anticoagulant, and the second patient reported to be successfully treated with an immunomodulatory regimen including rituximab.
Comparison of Pain During Two Methods of Urine Collection in Preterm Infants
Authors: El-Naggar Walid , Yiu Ashley , Mohamed Adel , Shah Vibhuti , Manley Jennifer , McNamara Patrick , Taddio Anna
Published: May 2010

BACKGROUND:

Suprapubic aspiration (SPA) and urine catheterization (UC) are performed frequently in preterm neonates to rule out urinary tract infection; however, a comparison of the pain caused by both procedures has not been made previously.

OBJECTIVE:

To compare pain responses in preterm infants who are undergoing urine collection by using SPA versus UC.

METHODS:

Prospective, single-blind, randomized clinical trial was conducted in 2 NICUs. Preterm infants who required urine samples for microbiologic analysis were randomly assigned to undergo either SPA or UC. The infants' facial and physiologic responses were videotaped during the procedure and later scored by a research assistant who was blind to the method of urine collection. The primary outcome measure was facial-grimacing during the procedure, which was assessed by measuring the percentage of time the infants displayed brow-bulging. Secondary outcomes included changes in heart rate (beats per minute), oxygen saturation (%), and procedural success rate.

RESULTS:

Forty-eight preterm infants participated. Characteristics did not differ (P > .05) between groups. The mean (SD) percent brow-bulging score was higher in the SPA group than in the UC group (67% [34] vs 42% [38]; P = .02). Heart rate and oxygen saturation did not differ (P = .50 and .74, respectively). The procedure-success rate, although lower in the SPA group, was not statistically different (60% vs 78%; P = .17).

CONCLUSIONS:

SPA was more painful than UC, as assessed by brow-bulging, and had a tendency to be associated with a higher rate of procedure failure. These findings should be taken into consideration when choosing between these 2 procedures for preterm infants who undergo urine sampling.
Reprocessing texts. The fine line between retranslating and revising
Authors: Paloposki Outi , Koskinen Kaisa
Published: May 2010

Retranslations are a frequent object of study in Translation Studies. They can be used as data for a number of research problems, or retranslation can be studied as a phenomenon on its own. There are no large-scale surveys on retranslation, however, let alone surveys that would be coupled with in-depth case studies, no doubt due to the laboriousness and complexity of the task. Our own interest in the issue started from a small-scale project testing the so-called Retranslation Hypothesis, but gradually our research expanded into a wider range of questions. We have addressed three main areas: the extent and proportion of retranslation in Finland; the motives for and reception of retranslations (publishers, critics); and finally, what happens to a text when it is either retranslated or revised (textual analysis). For this purpose, we have compiled three different sets of data from the Finnish context. These sets consist of synchronic data (retranslations and their reviews from the year 2000), diachronic data (charting the retranslation history of classics shortlisted in 1999 and 1887) and case studies (by e.g. Victor Hugo, Nikolai Gogol, Astrid Lindgren and Juan Valera translated into Finnish). This paper presents an overview of the results of our investigation, argues for a need for a comprehensive treatment of retranslation as a phenomenon, and discusses the implications of textual analysis for the understanding of the fuzzy area between retranslation and revision. The cases presented include Hugo’sLes Misérables, Gogol’sDead Soulsand Lagerlöf’sGösta Berling.
Data Submission Standards and Evidence Requirements
Authors: Abrams Jeffrey , Erwin Robert , Fyfe Gwen , Schilsky Richard L.
Published: May 2010

Presented are recommendations of the Data Submission Standards and Evidence Requirements panel from the Conference on Clinical Cancer Research along with the U.S. Food and Drug Administration's response to these recommendations.
Integrative and Behavioral Approaches to the Treatment of Cancer-Related Neuropathic Pain
Authors: Cassileth Barrie R. , Keefe Francis J.
Published: May 2010

Integrative oncology is the synthesis of mainstream cancer care and evidence-based complementary therapies. Complementary strategies include massage therapies, acupuncture, fitness, and mind–body techniques, which take advantage of the reciprocal relationship between the mind and body. Neuropathic pain—and pain more generally—is part of a complex process involving the whole physical and psychosocial being, therefore requiring an integrative management approach. Several studies have demonstrated, for example, that social context plays an important role in the perception of pain and that a patient's coping strategies can influence the persistence of pain. In this article, we briefly describe research illustrating the promise of integrative approaches for the treatment of cancer-related neuropathic pain.
Types and Epidemiology of Cancer-Related Neuropathic Pain: The Intersection of Cancer Pain and Neuropathic Pain
Authors: Lema Mark J. , Foley Kathleen M. , Hausheer Frederick H.
Published: May 2010

Neuropathic pain—pain resulting from a lesion, damage, or dysfunction of the somatosensory nervous system—can arise through several distinct etiologies ranging from toxicity, surgery, radiation, and trauma to congenital disorders. Neuropathic pain is widely recognized as a common consequence of cancer and results from administration of several common oncology drugs. It not only impacts quality of life, but it also impacts patient outcomes because of resulting treatment delays, dose reductions, and discontinuations. We estimate that the cost of the problem in the U.S. alone is approximately $2.3 billion. Despite its widely recognized importance, there is a paucity of reliable information available regarding the incidence, prevalence of patient-and physician-reported severity, and time course of cancer-related neuropathic pain. To address this severe knowledge gap, we need new, high-quality, population-based studies of individual cancer pain syndromes and conditions. However, in order to gather this information, we also need substantial improvements in the specific classification of cancer-related neuropathic syndromes and better validated diagnostic tools that can help to elucidate the incidence, prevalence, severity, and potential economic impact of cancer-associated neuropathies.
Commentary: Tackling the Challenges of Developing Targeted Therapies for Cancer
Authors: Schilsky Richard L. , Allen Jeff , Benner Joshua , Sigal Ellen , McClellan Mark
Published: May 2010

This article comments on the approaches to solving problems in the development of targeted drug therapies for cancer as outlined by expert collaborative panels and described in this issue by Amit et al., Abrams et al., and Clark et al.
Introducing the Infrastructure Planning Commission
Authors: Pitt Michael
Published: May 2010

The new Infrastructure Planning Commission started receiving its first planning applications for nationally significant infrastructure in England and Wales in March 2010. Chairman and ICE fellow Michael Pitt explains.
How to specify lower-carbon, more sustainable concrete
Authors: Higgins Denis
Published: May 2010

Construction clients are increasingly concerned with sustainability and looking to reduce the carbon footprint of their projects. Denis Higgins of the UK Cementitious Slag Makers Association explains how civil engineers can minimise the embodied carbon dioxide content of concrete.
Working together to attract tomorrow's engineers
Authors: Jackson Paul
Published: May 2010

Great efforts are being made to engage school children in engineering from an early age, but coverage in the UK is often inconsistent. Paul Jackson, chief executive of EngineeringUK, reports on a new initiative to fill in the gaps.
Extending London's Docklands Light Railway to Woolwich
Authors: Alder Andy , Dhanda Daljit , Hillyar Wayne , Runacres Alan
Published: May 2010

The £180 million, 2·5 km extension of London's Docklands Light Railway to Woolwich Arsenal has provided the capital with another much-needed cross-river transport link. Completed in January 2009, the project included the construction of twin 5·3 m diameter running tunnels through chalk containing highly abrasive flints under the Thames using an earth-pressure-balance tunnel-boring machine. It also included cut-and-cover approaches, an underground station and an emergency shaft on the river bank. Major challenges included tunnelling under sensitive infrastructure and the Thames, and working adjacent to an existing operational railway at Woolwich Arsenal. This paper describes the design and construction of the project and how the challenges were overcome.
Yangtze River: China's golden waterway
Authors: Peng Wu , Shuai Cao Feng , Xin Xiao
Published: May 2010

The 6380 km long Yangtze River is the longest in China and third longest in the world. With more than 3600 branches it provides a total of 65 000 km of waterways, over half of the country's inland navigation network. This paper describes China's ‘golden waterway’ and its huge national and regional economic benefits. It reports on the recent channel improvement projects on the trunk line, including the Three Gorges dam and major estuary works, which have significantly increased both reliability and capacity – and resulted in a direct stimulus to economic growth. A further £4 billion of improvements are now planned.
Ship design trends and the implications for port design
Authors: Byrne David
Published: May 2010

This paper looks at trends in ship dimensions for all major ship categories, using the underlying economic determinants to describe why the changes have occurred in the past and what might be expected in the future. The implications of the changes in the design and operation of ships on port infrastructure are discussed.
Impacts of climate change on waterborne transport
Authors: Hawkes Peter , Pauli Gernot , Moser Hans , Arntsen Øivind , Gaufres Pierre , Mai Stephan , White Kathleen
Published: May 2010

This paper is based on a recently completed Pianc report on climate change and navigation. It explains how navigation may be affected by climate change and where actions might be taken to develop adaptation strategies, mitigation measures and investments in a proactive way. The paper focuses on the potential impacts, both damaging and beneficial, on infrastructure, vessels, access and transport management – and concludes with a positive outlook.
The economic role of inland water transport
Authors: Lambert Bruce
Published: May 2010

The world's largest users of inland navigation are China, Europe and the USA. Inland water transport exists in other markets, but generally waterways are underutilised compared to other modes. This paper outlines the various groups involved in inland navigation – including barge operators, shippers, infrastructure providers and ports – and their relationships. It then discusses the future of inland waterways and how information, infrastructure and institutions can improve waterway operations.
Appropriate drainage systems for a changing climate
Authors: Faram M. G. , Ashley R. M. , Chatfield P. R. , Andoh R. Y. G.
Published: May 2010

Sustainable drainage systems are increasingly seen as a better way of draining urban areas, being ‘more natural’, less resource intensive and offering water quantity and quality control with amenity benefits. Sustainable drainage systems ‘greening’ can also reduce heat island effects. However, little attention has been given to assessing the real value and sustainability of the approach and uncertainties remain over performance and robustness, as well as ownership and maintenance. Received wisdom suggests that sustainable drainage systems have potential to help cope with climate change, while offering wider sustainability benefits over traditional piped drainage. The inherent adaptability of sustainable drainage systems allows them to be implemented incrementally as climate change knowledge advances. This paper provides evidence from a range of initiatives to show how sustainable drainage systems can contribute to a portfolio approach to tackling the problems of climate change. The need for political intervention and enhanced stakeholder engagement to support this type of approach is highlighted.
Briefing: Carbon critical design
Authors: Clarke B.
Published: May 2010

It was intended that the United Nations conference on climate change in Copenhagen in 2009 would reach a global agreement on carbon emissions, which would have had an impact on the design of civil engineering structures. This did not happen, but the UK, through the Climate Change Act of 2008 produced as a result of the Kyoto protocol of 1997, has made a commitment to reduce carbon emissions. As a result the concept of low/zero carbon design and construction is now being developed, starting with zero carbon homes by 2016 and other zero carbon buildings by 2019. The principles of zero carbon design or carbon critical design based on energy efficiency and low carbon technology are being developed so that new builds will meet the carbon compliance targets of 2020 and 2050. Carbon critical design means a whole life systems approach to design, with carbon as a key design parameter.
Briefing: UK's Engineering Council guidance on sustainability
Authors: Bogle D.
Published: May 2010

This article describes the recent development and publication by the UK's Engineering Council of a set of sustainability principles and related guidance primarily for engineers, but with a potentially wider audience. This was developed by bringing together expert thinking from across the engineering profession and distilling it into a clear and concise set of principles that are relevant to all areas of engineering. It has been welcomed as a milestone in the development of the profession.
Briefing: New geogrid technology for ground stabilisation
Authors: Dixon J. , Hall C.
Published: May 2010

This paper discusses the development and sustainability benefits of using geogrids in ground and reinforced soil projects. It also describes how the latest advances in geogrid technology have delivered significant savings (up to 50%) in carbon dioxide emissions, as well as cost and time savings, when compared with more conventional stabilisation techniques.
Briefing: Green information technology (IT) infrastructure
Authors: Sudworth T.
Published: May 2010

Two per cent of global carbon dioxide emissions are caused by the current information technology (IT) hardware in use at present. This includes equipment such as PC servers, cooling, power supplies, networks, printers and disk storage. Global IT spending is projected to reach approximately US$2 trillion in 2010, with a compound growth rate in spending of over 6% (IDC, 2009). If left unchecked, then with the continued expansion in IT spending, which is being used to drive commerce and industry, carbon dioxide emissions will continue to increase or even accelerate. This, coupled with large increases in the cost of the power to run all this hardware, has now created two major problems for all IT infrastructure users: how to convince customers (who increasingly demand green credentials from their engineering partners) that they are running a green IT operation, and more directly, particularly in the current economic climate, how to reduce the size of power bills.
Delivering sustainable bridges to help tackle climate change
Authors: Zhang C.
Published: May 2010

To tackle climate change, the UK government has set a national goal of reducing carbon dioxide emissions by 34% by 2020 based on the 1990 level. The construction industry is a major contributor to such emissions and has great potential to play a significant role. Much attention to date, however, has focused on reducing carbon dioxide emissions of buildings while the environmental impact of civil infrastructure has been far less well documented. This paper intends to contribute to bridging this knowledge shortfall by considering the environmental impact of bridges. The major sources of carbon dioxide emissions throughout the life cycle of a bridge are first identified and discussed in detail. Based on these discussions, major areas for improvement are identified to enable bridge designers to move towards sustainable bridge delivery. The slow adoption of sustainable principles is highlighted within the bridge engineering sector and measures to mobilise practical actions are proposed. Finally, the paper presents some conclusions and makes recommendations for further research.
Delayed collapse of cut slopes in stiff clay
Authors: Potts D. M. , Kovacevic N. , Vaughan P. R.
Published: May 2010

Delayed failure of railway cutting slopes in stiff clays excavated in the nineteenth and early twentieth centuries has been studied for some forty years. Known failures have generally been deep-seated. More recently failures have been a problem in the slopes of motorway cuttings and embankments, although generally these have been shallow. The average operational strength at failure in these slides has been significantly less than the peak strength, and progressive failure has been postulated as the probable cause of this. Progressive failure can now be analysed using advanced numerical techniques. A series of coupled finite element analyses have been conducted assuming strain-softening soil with properties based on the Brown London Clay, and the results are reported. They show that progressive failure is considerable, and fully explain the observed field behaviour. The delays experienced in the field are also recovered by the analyses. Progressive failure is generated primarily by the high lateral stresses in the soil prior to excavation. The rupture surface generated spreads horizontally from the toe as the soil swells, and differs significantly from the critical surface predicted by limit equilibrium analysis. The average strength on it at collapse is significantly lower than that obtained by back analysis by limit equilibrium methods. It becomes lower as lateral stress increases, but the effect is compensated by the increasing depth of rupture. The roll of the hydraulic surface boundary condition, which is controlled by climate, is important in controlling collapse. The implications of the findings for monitoring and for remedial works in existing slopes is discussed.
Experimental analysis of the effects of fluid—solid coupling on the velocity of elastic waves in saturated porous media
Authors: Gajo A. , Fedel A. , Mongiovì L.
Published: May 2010

This paper briefly reviews the characteristics of fluid—solid coupling in the dynamic behaviour of saturated porous media and describes the installation and use of piezoceramic transducers for the simultaneous measurement of longitudinal and rotational waves in triaxial samples. The comparison between longitudinal and rotational wave velocities measured in dry and watersaturated samples is described and analysed in detail. Two soils with different permeability features are investigated. The comparison shows that a reliable interpretation of rotational wave velocities of both permeable and impermeable saturated soils can be obtained if the effects of

viscous and inertial couplings are taken into account using Biot's theory. The same conclusions apply to the longitudinal wave velocities of impermeable saturated soils. In contrast, the interpretation of longitudinal wave velocities of permeable saturated soils gives an elastic stiffness value which is underestimated with respect to the value obtained from dry soils. Finally, the accuracy with which the small-strain stiffness of saturated soils can be evaluated from dynamic tests is discussed.
DEM simulations of thermally activated creep in soils
Authors: KWOK C.-Y. , BOLTON M.D.
Published: May 2010

Discrete element modelling (DEM) has been used to simulate creep in assemblies of spherical grains possessing an interfacial coefficient of friction that varies with sliding velocity according to rate process theory. Soil stiffness is represented by a pair of values of linear spring stiffness normal and tangential to each inter-granular contact, and the limiting coefficient of contact friction is described as varying linearly with the logarithm of sliding velocity. DEM simulations of an assembly of 3451 spheres reproduce a number of significant phenomena including: creep rate as a function of the mobilisation of deviatoric stress; initially linear decay of creep strain rate with time plotted on log-log axes and with a slope m in the range −0·8 to −1; and ultimate creep failure in triaxial simulations at high deviatoric stress ratios. Creep-induced failure is shown to occur at a unique axial strain for a given state of initial packing, and to be linked with dilatancy. The numerical results are compared quantitatively with the test data of soils from the literature. The effects of activation energy are considered in relation to the different magnitudes of creep encountered in sands and clays.
Discrete element modelling of railway ballast under monotonic and cyclic triaxial loading
Authors: LU M. , McDOWELL G.R.
Published: May 2010

Triaxial samples of railway ballast have been modelled using clumps of spheres. The bulk of the clump is formed from ten balls in a tetrahedral shape. The interlocking and breaking of very small asperities which find their way into the voids is modelled using weak parallel bonds between clumps. The interlocking and fracture of larger asperities has been modelled by bonding eight small balls to the clump. Monotonic tests have been performed on triaxial samples under a range of confining pressures from 15 kPa to 240 kPa and the results compared with existing experimental data. Tests were also simulated using uncrushable clumps to highlight the important role of asperity abrasion. Cyclic triaxial tests were then simulated on the same aggregates using the same microparameters as the monotonic tests under a range of stress conditions and the results were compared to existing experimental data for the same simulated ballast. The results show that the clumps are able to capture the behaviour of ballast under both monotonic and cyclic conditions and asperity abrasion is shown to play an important role in governing strength and volumetric strain under monotonic loading, and on permanent strains under cyclic loading. The new contribution is therefore to show that it is possible to model a real granular material under static and cyclic conditions, thus providing much micromechanical insight.
The security consultant in the design process: a risk-led approach
Authors: Tomlinson Chris , Nelson Bill
Published: May 2010

Any visitor to the Middle East will be familiar with the none-too-unattractive ad hoc security measures, usually imposed after a serious security incident; invariably these are incongruous mitigation and worryingly of doubtful efficacy. The current authors believe that in the Middle East there is a lack of knowledge of security risk management and what it offers the built environment. This is illustrated by the fact that security consultants are often appointed almost as an afterthought in many projects. Unfortunately security risk management planning and its associated design and engineering activities have never enjoyed the same obligatory status as those that surround the design of fire prevention and safety. This ignores the potential to develop a risk-led approach offering savings to clients in terms of proportionality, procurement phasing, operational efficacies and, importantly for many clients and their clients, pleasing aesthetics. This article (written’by two experienced Arup security consultants) seeks to show what is on offer in the Middle East in terms’of focused security risk consultancy and to champion the cause of security risk management in the region's built space.
Increasing ‘local content’ in infrastructure procurement. Part 1
Authors: Wells Jill , Hawkins John
Published: May 2010

The funding invested in infrastructure construction in low-income countries (particularly the countries of sub-Saharan Africa) does not benefit contractors, suppliers and workers from those countries as much as it might. Increasing the input of local labour, goods and services could make a major contribution to economic growth and the achievement of the millennium development goals. This paper aims to show policymakers that expanding the local content of infrastructure construction is an achievable objective and to provide practical guidance on how to do it. Based on an extensive literature search, this paper (Part 1 of a double paper) shows that the procurement process can serve as a powerful tool to promote local content in infrastructure construction. However, a number of challenges are identified, notably the preference of clients, donors, engineers and the business community for expensive, high-tech and large-scale projects that are not within the capability of the local industry, as well as the failure of international agencies to balance objectives. In Part 2 of this work, some suggestions are put forward for overcoming the challenges and promoting specific policy objectives through minor changes to the procurement process.
Increasing ‘local content’ in infrastructure procurement. Part 2
Authors: Wells Jill , Hawkins John
Published: May 2010

Part 1 of this paper argued that more could be done to ensure that funding invested in infrastructure in low-income countries benefits contractors, suppliers and workers in those countries. Increasing local content in the construction and maintenance of infrastructure would generate income and employment locally and contribute to economic growth and poverty reduction. The use of procurement to achieve this objective is supported by international agencies and has been practised by a number of countries over many years. While recognising that there are very real capacity constraints, this paper shows that there is room – within existing procurement guidelines and without contravening international procurement rules – to do more to promote local content in infrastructure projects. This can be done without necessarily sacrificing on cost or quality. Suggestions include actions at earlier stages of the procurement cycle (during project planning and design processes) and some minor modifications to the tender process.
Aerodynamic, hydro-aerodynamic and destructive testing
Authors: Gan Chowdhury A. , Bitsuamlak G. , Simu E.
Published: May 2010

Hurricane-induced losses in the USA increased from US$1·3 billion per year pre 1990 to US$ 36 billion per year post 2000. In 2005, the losses exceeded US$100 billion. Hurricanes caused over 1400 fatalities in 2004–2005. Research focusing on the complex interaction between hurricanes and the built environment is therefore necessary to develop a cohesive and systemic approach to building hurricane-resilient communities. Full- and large-scale experimental research at Florida International University is focusing on the development of a hurricane wind and wind-driven-rain testing facility (generically named the ‘wall of wind') capable of subjecting single-storey building models to hurricane effects. Three different types of tests are envisioned: aerodynamic (pressure tests for low-rise buildings, rooftop equipment and mitigation); hydro-aerodynamic (wind-driven-rain intrusion through roof secondary water barriers, soffits and window/door/wall interfaces); and destructive (roof tile and shingle tests, roof fascia tests). This paper describes the new facility, provides details on hurricane wind and rain simulation, discusses the three different types of testing capabilities and states the goals of the research aimed at developing hurricane-resilient communities.
New developments in rain–wind-induced vibrations of cables
Authors: Taylor I. J. , Robertson A. C. , Wilson S. K. , Duffy B. R. , Sullivan J. M.
Published: May 2010

On wet and windy days, the inclined cables of cable-stayed bridges can experience large amplitude, potentially damaging oscillations known as rain–wind-induced vibration (RWIV). RWIV is believed to be the result of a complicated non-linear interaction between rivulets of rain water that run down the cables and the wind loading on the cables from the unsteady aerodynamics; however, despite a considerable international research effort, the underlying physical mechanism that governs this oscillation is still not satisfactorily understood. An international workshop on RWIV was held in April 2008, hosted at the University of Strathclyde. The main outcomes of this workshop are summarised in the paper. A numerical method to investigate aspects of the RWIV phenomenon has recently been developed by the authors, which couples an unsteady aerodynamic solver to a thin-film model based on lubrication theory for the flow of the rain water to ascertain the motion of the rivulets owing to the unsteady aerodynamic field. This novel numerical technique, which is still in the relatively early stages of development, has already provided useful information on the coupling between the external aerodynamic flow and the rivulet, and a summary of some of the key results to date is presented.
Technologies to measure indicators for road user charging
Authors: Ochieng W. Y. , Quddus M. A. , North R. J. , Noland R. B.
Published: May 2010

A technically and economically feasible road user charging scheme should be based on quantities that are readily and accurately measurable, as well as being directly variable with the amount of road use and its impact on the environment and society. A key requirement for a pricing scheme is that the charging regime used should be easy for motorists to understand, but at the same time flexible enough for the operator to implement a wide range of policies to meet different aims. A set of variable road user charging indicators is identified herein by considering both the associated costs of a trip and the operational requirements for a feasible road pricing scheme. The study then focused on identifying a set of currently feasible technologies to measure these variables in real-time with high accuracy. Particular attention was paid to the need accurately to track vehicle movements and link these movements to geographical areas and road types, and the key pollutants and particulate matter, all of which have different potential effects that are in some cases dependent on location and time of emissions. Other issues, such as congestion measurement, are also discussed.
Reliability of congestion measures: Stockholm's case
Authors: Morán C. , Bang K.-L.
Published: May 2010

The Stockholm congestion charging trial was implemented with the aim of satisfying a number of transport policy objectives related to reducing car use in the central area of Stockholm. However, the multifaceted nature of congestion that the charges aimed to alleviate was not technically defined. The traffic impact evaluation efforts were based on survey results for chosen links without any scientific review of the dynamic character of congestion or any investigation of the statistical characteristics of the chosen congestion indicator. Neither was there any analysis of area networks nor any calculation of an overall indicator. Based on a literature review, approaches for defining congestion and a number of alternative congestion performance measures were selected. Data from the trial ‘before' and ‘after' surveys were used to estimate congestion levels and the accuracy of the performance measures. Specific issues and lessons regarding the quality of the data collection are discussed. Accuracy rankings are presented for different cases, concluding that some performance measures showed better reliability in all situations whereas others proved to always be less reliable. These findings are used as a basis for recommendations regarding the implementations of the congestion indicators studied.
Geomorphic dam-break flows. Part I: conceptual model
Authors: Leal J. G. A. B. , Ferreira R. M. L. , Cardoso A. H.
Published: May 2010

This paper presents a one-dimensional conceptual model for simulating geomorphic dam-break flows. The model is based on conservation laws drawn from continuum mixture theory that are integrated over the flow depth, assuming that the flow is composed of two transport layers. Closure equations were derived from the review and reanalysis of previous studies on granular flow, debris flow and sheet flow. The sediment transport is modelled assuming capacity regime. The closure equation coefficients are estimated based on a large set of experiments available in the literature. The validity of the model is discussed by computing the most relevant dimensionless parameters. The model is expected to simulate adequately the friction at the wave front and the sheet flow throughout the wave profile. Ultimately, although the problem incorporates complex phenomena, the model can be easily implemented by practising engineers for simulating one-dimensional geomorphic dam-break flows. The implementation and the verification of the adequacy of the model for simulating these flows are presented in a companion paper.
Geomorphic dam-break flows. Part II: numerical simulation
Authors: Leal J. G. A. B. , Ferreira R. M. L. , Cardoso A. H.
Published: May 2010

This paper presents the comparison between numerical results obtained with a conceptual model proposed in a companion paper and experimental results collected from previous studies. The numerical model is based on a finite difference approximation using the MacCormack scheme with a total variation diminishing high-resolution correction term for the mixture mass and momentum conservation equations and an artificial viscosity term for the sediment mass conservation equation. From the comparison between numerical and experimental results, it can be verified that the model generally gives results in good agreement with the experimental data and the wave structure is in accordance with what has been reported in previous studies. The estimation of model parameters based on existing sheet-flow data seems a promising way of developing models without arbitrary choice of values for tuning parameters. Some limitations can be identified, namely the equilibrium sediment transport approach implies that the model cannot simulate the hydraulic jump formed in the higher mobility bed for dry bed conditions. The use of a constant friction factor does not allow simulating the exact wave-front location for all instants in time.
Colloid‐Facilitated Metal Transport in Peat Filters
Authors: Kalmykova Yuliya , Rauch Sebastien , Strömvall Ann‐Margret , Morrison Greg , Stolpe Björn , Hassellöv Martin
Published: May 2010

The effect of colloids on metal retention in peat columns was studied, with the focus on colloids from two sources—organic matter leached from peat, and introduced organic and hydrous ferric oxide (HFO) colloids. A significant fraction of metals was found to be associated with peat‐produced organic colloids; however the concentrations of organic colloids leached are low (trace concentrations) and temporal and have a limited effect on the efficiency of peat filters. In contrast, the presence of organic and HFO colloids in the input water causes a significant decrease in the performance of peat filters. Organic colloids were identified as the main vector of cadmium, copper, nickel, and zinc, while lead is transported by both organic and HFO colloids. The colloidal distribution of metals obtained in this study has important implications for the mobility of trace metals in porous media. The occurrence of colloids in the input waters and their characteristics must be considered when designing water treatment facilities.
1000 Fieldwork Hours: Analysis of Multi-Site Evidence
Authors: Holmes Jeffrey D. , Bossers Ann M. , Polatajko Helene J. , Drynan Donna P. , Gallagher MaryBeth , O'Sullivan Clare M. , Slade Anita L. , Stier Jill J. , Storr Caroline A. , Denney Julie L.
Published: May 2010

Background. Internationally, the World Federation of Occupational Therapists has established a minimum of 1,000 hours as the fieldwork standard.Purpose. To examine student development in fieldwork across placements to determine if students achieve entry-level competence after completion of 1,000 hours of fieldwork.Methods. Archival data (N=400) from six occupational therapy programs were analyzed to examine the acquisition of fieldwork competency over time as measured by the Competency Based Fieldwork Evaluation Scale.Findings. Competency scores increased with each fieldwork placement, the majority of students achieved entry-level scores upon completion of their final fieldwork placement. While, on average, some competency scores exceeded entry level by 1,000 hours, Practice Knowledge, Clinical Reasoning, and Facilitating Change fell just short.Implications. The identification of a plan for addressing the lower ratings in these three competencies should be considered.
Validation française de questionnaires de participation sociale auprès d'aînés en situation d'incapacités
Authors: Poulin Valérie , Desrosiers Johanne
Published: May 2010

Contexte. Pour dresser le portrait complet du fonctionnement des aînés en situation d'incapacités, il est utile d'inclure une évaluation de leur participation sociale. Toutefois, très peu de questionnaires mesurant ce concept sont disponibles en langue française.But. L'étude visait à traduire les questionnaires Participation Measure for Post-Acute Care (PM-PAC) et Impact on Participation and Autonomy Questionnaire (IPAQ), puis à évaluer leur fidélité test-retest et leur validité convergente en les comparant au questionnaire Mesure des habitudes de vie (MHAVIE).Méthodologie. Trente aînés ayant des incapacités physiques ont répondu à deux moments aux trois questionnaires.Résultats. La fidélité test-retest du score total des versions francophones de I'IPAQ (coefficient de corrélation intraclasse (CCI): 0,86) etdu PM-PAC (CCI: 0,90) est élevée. Les scores totaux de participation des trois questionnaires sont modérément associés (rs: 0,53 à 0,64).Conséquences pour la pratique. L'étudepermet d'offrir aux ergothérapeutes cliniciens et aux chercheurs francophones deux nouveaux outils valides pour l'évaluation de la participation sociale.