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Abstract: High speed surveys have become a key source of information to support condition assessment and management of pavement assets. These surveys can be applied network wide to obtain data on the surface condition and structural robustness of the pavement. The success of high speed surveys is demonstrated by the growth in the survey industry and the wide range of measurement equipment that has become available. However, these advances bring challenges to road administrations in determining the most appropriate survey to specify for their networks, in selecting the equipment, and in ensuring that the condition parameters delivered will be suitable to support asset management decisions. Although standards have been developed for some of the measurements provided by high speed systems, the focus tends to be highly technical, often not considering the wide ranging needs of routine network level implementation. The HiSPEQ project has the objective of developing guidance and advice to help road administrations to understand high speed road survey equipment, and to help them in specifying the survey requirements, quality regimes and processing procedures. The project has considered high speed survey data that can be used to assess pavement structural robustness. It has investigated the measurement of pavement shape, visual condition, deflection and structure. Via review of current specifications both within and outside the EU, and direct consultation with practitioners and administrations, the project has proposed a set of core requirements for high-speed surveys of pavement surface and structural condition. These requirements have been used to propose survey specification templates that road administrations could use when developing survey requirements for their own networks. Guidance has been developed to accompany the specifications, to assist road administrations understand the requirements and the implications of different levels of resolution and accuracy on the use of the data. The project has also proposed a set of quality assurance processes to consider when specifying condition surveys.
Keywords: high-speed surveys, profile, shape, deflection, quality assurance, accreditation
Published in DiRROS: 03.03.2025; Views: 0; Downloads: 0
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Abstract: Instrumentation is often used to monitor the performance of engineered infrastructure slopes. This paper looks at the current role of instrumentation and monitoring, including the reasons for monitoring infrastructure slopes, the instrumentation typically installed and parameters measured. The paper then investigates recent developments in technology and considers how these may change the way that monitoring is used in the future, and tries to summarize the barriers and challenges to greater use of instrumentation in slope engineering. The challenges relate to economics of instrumentation within a wider risk management system, a better understanding of the way in which slopes perform and/or lose performance, and the complexities of managing and making decisions from greater quantities of data.
Keywords: geotechnical monitoring, climate change, pore pressures, displacements
Published in DiRROS: 03.03.2025; Views: 0; Downloads: 2
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Abstract: Chitosan is a water-soluble polysaccharide with good adherence to negatively charged surfaces and reported antimicrobial and anti-inflammatory properties. Coating the surfaces of medical devices with chitosan is a promising strategy for harnessing these benefits. However, the surface properties of commercial polymers need to be altered to enable the bonding of thin chitosan films. In this study, the adhesion of chitosan onto plasma-treated polyvinyl chloride (PVC) and the metabolic activity of urothelial cells on chitosan-coated medical-grade PVC used for the synthesis of urinary catheters were evaluated. To improve the adhesion of chitosan onto the PVC catheters, PVC samples were made “super-hydrophilic”. PVC substrates were briefly treated with a powerful hydrogen plasma and weakly ionised oxygen plasma afterglow to obtain a chlorine-free surface film, which was rich in oxygen functional groups, followed by incubation of the plasma-treated substrates in an aqueous solution of chitosan. Then, urothelial RT4 cells were seeded on the treated and untreated PVC substrates, and their metabolic activity, confluency, and cell morphology were examined. X-ray photoelectron spectroscopy was used to measure the nitrogen concentration, which corresponded to the chitosan concentration on the substrate. The results showed that the substrates were uniformly covered by a thin layer of chitosan only on plasma-treated surfaces and not on untreated surfaces. Moreover, the chitosan coating provided a stimulated environment for cell adhesion and growth. In conclusion, the chitosan-coated super-hydrophilic PVC substrate shows potential to improve the overall performance and safety of medical devices such as urinary catheters.
Keywords: medical-grade PVC, chitosan coating, urinary catheter, urothelial cells, cytotoxicity, adhesion, biocompatibility
Published in DiRROS: 28.02.2025; Views: 46; Downloads: 20
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Published in DiRROS: 28.02.2025; Views: 73; Downloads: 0
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Abstract: Gymnosperms are a very old and small group of plants compared to angiosperms. Contemporary science recognizes about 650 extant conifers worldwide. This review focuses on species of the Pinaceae family found in Europe. There are 23 species from the genera Abies, Larix, Picea, and Pinus. Some of them are widespread in Europe, but others have fragmented and limited distribution and are classified as relic, endemic, or endangered. The aim of this review is providing cumulative information about the variability of needle morpho-anatomy, terpenes, and n-alkanes, as well as the genetics of the Pinaceae species, native to Europe. The first morpho-anatomical examinations of needles were conducted in the 19th century. A lot of species have been investigated up to now, but the population variability of many conifer species is still not known. The composition and abundance of terpenes differ between genera and families but also within the same genus, pointing to their taxonomic importance. n-Alkanes on the needle wax surfaces of conifers are sometimes very useful markers of species and population variability. The most abundant n-alkanes in Abies species are nonacosane (C29), hentriacontane (C31), or heptacosane (C27), whereas in Larix decidua and the majority of Picea species, C31 is predominant. C31 and C29 are the dominant n-alkanes in the genus Pinus. The most extensive population-genetic studies of European representatives of the Pinaceae family have focused on Abies alba, Picea abies, Pinus nigra, and Pinus sylvestris, but also examined endemic species such as Abies borisii-regis, A. cephalonica, A. nebrodensis, and Picea omorika. These studies hold significant practical value in assessing species’ evolutionary potential, devising strategies for long-term species conservation, identifying centers of diversity, detecting relict and ancestral populations, unveiling cryptic species and hybrids, and elucidating the taxonomic significance of species. These investigations are of great value not only on the biodiversity level, but also on the levels of ecology, physiology, taxonomy, and evolution.
Keywords: Europe, Pinaceae, conifers, needle morphology, needle anatomy, terpenes, n-alkanes, genetic markers
Published in DiRROS: 27.02.2025; Views: 77; Downloads: 52
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