414 research outputs found
Author response to: Cardiovascular risk factors in offspring exposed to gestational diabetes mellitus in utero: systematic review and meta-analysis
No full textLetter to the EditorThis commentary is an author response to Yu and colleagues regarding the manuscript entitled ‘Cardiovascular risk factors in offspring exposed to gestational diabetes mellitus in utero: Systematic review and meta-analysis’. We address their concern regarding minor errors in our manuscript, our search strategy and assessment of heterogeneity.Maleesa M. Pathirana, Zohra S. Lassi, Claire T. Roberts, and Prabha H. Andraweer
Agrobacterium tumefaciens-mediated transformation of axillary bud callus of Hibiscus rosa-sinensis L. ‘Ruby’ and regeneration of transgenic plants
No full textHibiscus rosa-sinensis L. is a popular ornamental species valued for its large brightly coloured ephemeral flowers and has a range of health-promoting properties. The value of H. rosa-sinensis could be improved even further if there were ways to prolong the display life of its short-lived flowers, and to improve its frost tolerance. Development of an efficient plant transformation and regeneration procedure that allows introduction of genes into the plant will greatly facilitate this. Here we outline a transformation and regeneration procedure that is the first to produce transformed H. rosa-sinensis plants successfully. We first optimised callus induction and shoot regeneration efficiency. The highest shoot regeneration frequency of 66.7 % was achieved in the cultivar ‘Ruby’ when callus induced from axillary buds using a basal medium supplemented with 2.22 μM benzylaminopurine and 2.47 μM β-naphthoxyacetic acid was cultured on shoot regeneration medium. The frequency of shoot regeneration from callus was lower in ‘Ben James’ and absent in ‘Bright Light’, indicating genotypic differences. When axillary bud-derived callus of ‘Ruby’ was co-cultured with Agrobacterium tumefaciens harbouring a β-glucuronidase (GUS) reporter plasmid, 49 % of calli produced shoots on selection media. All tested plantlets were confirmed as transformed based on the presence of the GUS transgene in the genomic DNA and GUS activity measurements. Roots were induced on transgenic plantlets using half-strength basal medium supplemented with 2.85 μM indole-3-acetic acid. This simple protocol can be used to improve the ornamental, agronomic and health-promoting traits of H. rosa-sinensis hitherto recalcitrant to A. tumefaciens-mediated transformation
Mapping the drivers of overdiagnosis to potential solutions
No full textExtract:In our collective enthusiasm to diagnose and treat disease, a growing body of evidence indicates that we may often be doing too much of a good thing. “Overdiagnosis” is now widely recognised to occur when people are labelled with or treated for a disease that would never cause them harm—often as a result of undergoing screening—and it can lead to the overuse of further tests and treatments. One example is thyroid cancer,with estimates that over 500 000 people may have received overdiagnoses across 12 countries in the past two decades, leading to unnecessary surgery and lifelong medication for many. Overdiagnosis is a challenge to the sustainability of human health and health systems. Its causes—including the best of intentions—are as complex and multifaceted as the potential solutions. As part of the preparation for a possible national action plan in Australia, we searched the literature for causes of and responses to overdiagnosis. Here we provide the first comprehensive analysis of the possible drivers of overdiagnosis and related overuse, mapped to potential solutions
Sustainability in post disaster road infrastructure recovery projects and asset management
No full textCivil infrastructure and especially roads are being impacted with increasing frequency by flood, Tsunami,\ud
cyclone related natural and manmade disasters in the world. Responding to such events and in preparing for more\ud
regular and intense climate-change induced events in future, the road governing agencies are reviewing how postdisaster road infrastructure recovery projects are best planned and delivered. In particular, there is awareness that rebuilding such infrastructure require sustainable asset management strategies across economic, environmental and social dimensions.\ud
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A comprehensive asset management framework for pre and post disaster situations can minimize negative impacts on\ud
our communities, economy and environment. This research paper is focused on post disaster management in road\ud
infrastructures and road infrastructure asset management strategies used by road authorities. Analyzing the\ud
implications of disruption to transport network and associated services is an important part of preparing local and regional responses to the impacts of disasters. This research paper will contribute to strategic infrastructure asset planning, management leading to safe, efficient and integrated transport system that supports sustainable economic, social and environmental outcomes.\ud
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This paper also focuses on proper asset management, governance and engineering principles which should be\ud
followed and adopted in post disaster recovery projects to maximize sustainability in environmental, social and\ud
economic dimensions
Damage detection in cable structures using vibration characteristics
No full textCable structures find many applications such as in power transmission, in anchors and especially in bridges. They serve as major load bearing elements in suspension bridges, which are capable of spanning long distances. All bridges, including suspension bridges, are designed to have long service lives. However, during this long life, they become vulnerable to damage due to changes in loadings, deterioration with age and random action such as impacts. The main cables are more vulnerable to corrosion and fatigue, compared to the other bridge components, and consequently reduces the serviceability and ultimate capacity of the bridge. Detecting and locating such damage at the earliest stage is challenging in the current structural health monitoring (SHM) systems of long span suspension bridges. Damage or deterioration of a structure alters its stiffness, mass and damping properties which in turn modify its vibration characteristics. This phenomenon can therefore be used to detect damage in a structure. The modal flexibility, which depends on the vibration characteristics of a structure, has been identified as a successful damage indicator in beam and plate elements, trusses and simple structures in reinforced concrete and steel. Successful application of the modal flexibility phenomenon to detect and locate the damage in suspension bridge main cables has received limited attention in recent research work. This paper, therefore examines the potential of the modal flexibility based Damage Index (DI) for detecting and locating damage in the main cable of a suspension bridge under four different damage scenarios. Towards this end, a numerical model of a suspension bridge cable was developed to extract the modal parameters at both damaged and undamaged states. Damage scenarios considered in this study with varied location and severity were simulated by changing stiffness at particular locations of the cable model. Results confirm that the DI has the potential to successfully detect and locate damage in suspension bridge main cables. This simple method can therefore enable bridge engineers and managers to detect and locate damage in suspension bridges at an early stage, minimize expensive retrofitting and prevent bridge collapse
Flexibility in adaptation planning: When, where and how to include flexibility for increasing urban flood resilience
No full textThe magnitude and urgency of the need to adapt to climate change is such that addressing it has been taken up by the United Nations as one of the sustainable development goals - Goal 13 (SDG13) in 2015. SDG13 emphasises the need to strengthen resilience and adaptive capacity to climate related hazards and natural disasters. Coping with urban floods is one of the major needs of climate adaptation, where integration of climate change responses into flood risk management policies, strategies and planning at international, national, regional and local levels is now the norm. However, much of this integration lacks effectiveness or real commitment from stakeholders involved in adaptation planning and implementation. Hence this research has focused on integrating flexibility based adaptation responses into an urban flood risk management context. The research has synthesised flexible adaptation practices from several disciplines including information technology, automobile and aerospace manufacturing. The outcomes of the research are brought together in a framework for structuring local adaptation responses and an adaptation planning process based on flexibility concepts. The outcomes provide a way to assist with the identification of the appropriate nature and type of flexibility required; where flexibility can best be incorporated; and when is the most appropriate time to implement the flexible adaptation responses in the context of urban flooding.Dissertation submitted in fulfilment of the requirements of the Board for Doctorates of Delft University of Technology and of the Academic Board of the UNESCO-IHE Institute for Water Education.Hydraulic Structures and Flood Ris
Development of an Efficient Modelling Approach to Support Economically and Socially Acceptable Flood Risk Reduction in Coastal Cities: Can Tho City, Mekong Delta, Vietnam
No full textFlooding is one of the most frequently occurring and damaging natural disasters worldwide. Quantitative flood risk management (FRM) in the modern context demands statistically robust approaches (e.g. probabilistic) due to the need to deal with complex uncertainties. However, probabilistic estimates often involve ensemble 2D hydraulic model runs resulting in large computational costs.Additionally, modern FRM necessitates the involvement of a broad range of stakeholders via co-design sessions. This makes it necessary for the flood models, at least at a simplified level, to be understood by and accessible to non-specialists.This study was undertaken to develop a flood modelling system that can provide rapid and sufficiently accurate estimates of flood risk within a methodology that is accessible to a wider range of stakeholders for a coastal city – Can Tho city, Mekong Delta, Vietnam.A web-based hydraulic tool, Inform, was developed based on a simplified 1D model for the entire Mekong Delta, flood hazard and damage maps, and estimated flood damages for the urban centre of Can Tho city (Ninh Kieu district), containing the must-have features of a co-design tool (e.g. inbuilt input library, flexible options, easy to use, quick results, user-friendly interface). Inform provides rapid flood risk assessments with quantitative information (e.g. flood levels, flood hazard and damage maps, estimated damages) required for co-designing efforts aimed at flood risk reduction for Ninh Kieu district in the future.Hydraulic Structures and Flood Ris
Wet Climate Drives Melanistic Giant Squirrel Ratufa macroura melanochora in Wet Zone of Sri Lanka
No full textThe species; Ratufa macroura exists in three different coat colorations. R. m. melanochora in Sri Lankan wet forests has morphologically diverged from the R. m. macroura in the intermediate zone and R. m. dandolena shared between Sri Lankan Dry zone and Mainland India. This study investigated the correlation of geo-climatic parameters with the morphometry and colorimetry of R.m. melanochora; the level of divergence of R. m. melanochora in morphological and vocal aspects from the other two subspecies; and the exact phylogenetic position of the Wet zone melanistic R. macroura. We studied 18 live and fresh specimens of R. macroura and 56 preserved museum skins housed at the National Museum, Colombo. We collected blood or fur samples, morphometric and anatomical data, and hair samples. Colorimetric data were obtained using an Ocean Optics portablespectrometer. Both morphometric and pelage-associated characters showed clinal variation with the rainfall and biogeographic distance. Squirrels in wetter areas have dark and long fur while fur length increased with the increasing biogeographic distance from the mainland. Hence the wet zone Giant Squirrels are larger and darker than the other two forms. The conducted multivariate analysis (PCA) to determine differences among three populations showed no clear clustering in both skin and skull morphometric values. The dorsal and ventral coat color gets darker as the cline moves from dry zone to wet zone, which makes the extreme wet zone individuals black in dorsal coloration. The spectral data of R. m. melanochora displayed the highest absorbance. The microscopic structure of hair changes distinctly with densely packed melanin granules and fizzy hair with an oval-shaped cross-section, which may be an adaptation to the humid environment that, in-turn may assist in thermoregulation. Other than above mentioned phenotypic characters, R. m. melanochora is vocally distinct with chatter calls with higher repertoire, lower pulse frequency, lower pulse duration, and lower amplitudes. The genetic divergence of R. m. melanochora, however, is not clear from the rest of the R. macroura in Sri Lanka. In minimum spanning networks inferred for cytochrome-b and 12s regions of the genus, the R. macroura population in Sri Lanka share the same haplotype cluster. According to the concatenated and coalescent analyses of cytochrome-b and 12s genes, R. m. melanochora shares the subspecies status with R. m. macroura and R. m. dandolena. This shows that R. m. melanochora is not genetically distinct as claimed by studied gene regions. This proves that the melanistic form of Sri Lankan Grizzled Giant Squirrel is a unique evolutionary entity shaped by a wet climate in its isolated island habitat.
Keywords: Melanism, Climate, Ratufa, Wet forest, Sri Lank
Figure 8 in Comparative osteology of the Danio (Cyprinidae: Ostariophysi) axial skeleton with comments on Danio relationships based on molecules and morphology
No full textFigure 8. Variation in the caudal skeleton of Danio. A, D. aequipinnatus (AMNH 15761); B, D. albolineatus (CU 77841); C, D. devario (CU 82548); D, D. kerri (CU 82554) note absence of the sixth hypural; E, D. malabaricus (MCZ 52399) note doubling of neural spines (arrow 1) and presence of the sixth hypural; F, D. pathirana (CU 85509); G, D. pulcher (CU 77840); H, D. quangbinhensis (AMNH 227913); I, D. regina (CU 82550); J, D. rerio (CU 82546); K, D. browni (CU 82553). Scale bars = 1 mm.Published as part of Sanger, Thomas J. & McCUNE, Amy R., 2002, Comparative osteology of the Danio (Cyprinidae: Ostariophysi) axial skeleton with comments on Danio relationships based on molecules and morphology, pp. 529-546 in Zoological Journal of the Linnean Society 135 (4) on page 538, DOI: 10.1046/j.1096-3642.2002.00014.x, http://zenodo.org/record/543433
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