The illusions of competition in the water sector: a response to the OFWAT/Cave consultations on introducing competition in the water sector in England and Wales

The paper provides a critical review of the role of liberalisation and competition in the water sector, based on empirical evidence from the UK and internationally. The paper is submitted as evidence to the official reviews of competition in water sector in England and Wales

Guided Tissue Regeneration in Heart Valve Replacement: From Preclinical Research to First-in-Human Trials

Heart valve tissue-guided regeneration aims to offer a functional and viable alternative to current prosthetic replacements. Not requiring previous cell seeding and conditioning in bioreactors, such exceptional tissue engineering approach is a very fascinating translational regenerative strategy. After in vivo implantation, decellularized heart valve scaffolds drive their same repopulation by recipient’s cells for a prospective autologous-like tissue reconstruction, remodeling, and adaptation to the somatic growth of the patient. With such a viability, tissue-guided regenerated conduits can be delivered as off-the-shelf biodevices and possess all the potentialities for a long-lasting resolution of the dramatic inconvenience of heart valve diseases, both in children and in the elderly. A review on preclinical and clinical investigations of this therapeutic concept is provided with evaluation of the issues still to be well deliberated for an effective and safe in-human application

Study of waterborne polyurethane materials under aging treatments. Effect of the soft segment length

Coatings made of waterborne polyurethane dispersions are a promising alternative to solvent-borne ones but their mechanical and thermal properties under harsh outdoor conditions such as high temperature and humidity are somewhat limited. In this work saturated polyesters (PBA) with different molecular weights (800–2600 g/mol) were synthesized by reacting adipic acid with 1,4 butanediol. These polyols, an internal emulsifier, and an aliphatic diisocyanate were used as raw materials to synthesize polyurethane (PU) aqueous dispersions with solids contents of 29–38 wt%. The increase of the molecular weight of the polyol decreased the mean particle size of the PU dispersions from 308 to 78 nm. Polyurethane (PU) films were obtained by water evaporation of the PU dispersions and they were annealed at 80 °C for 2 h. Accelerated aging studies were performed by submerging the PU films in the water at 80 °C for 2 h. The PU films synthesized with the polyols with lower molecular weight exhibited enhanced phase miscibility, giving place to storage and loss moduli of similar magnitudes in a wide temperature range and they were less susceptible to hydrolytic degradation. Microphase miscibility was favored when shorter polyols are used. Contact angle measurement and cross-hatch adhesion test on PU coatings placed on stainless steel plate, before and after annealing and water aging were carried out. All PU coatings retained the adhesion to the substrate after aging, the PU coatings synthesized with shorter polyols exhibited enhanced adhesion.The authors thank the University of Antioquia for the “Estudiante Instructor” grant and to CODI for the economic and time support on the project 785 registered in the act 2018-19331

Resilience for large ensemble computations

With the increasing power of supercomputers, ever more detailed models of physical systems can be simulated, and ever larger problem sizes can be considered for any kind of numerical system. During the last twenty years the performance of the fastest clusters went from the teraFLOPS domain (ASCI RED: 2.3 teraFLOPS) to the pre-exaFLOPS domain (Fugaku: 442 petaFLOPS), and we will soon have the first supercomputer with a peak performance cracking the exaFLOPS (El Capitan: 1.5 exaFLOPS). Ensemble techniques experience a renaissance with the availability of those extreme scales. Especially recent techniques, such as particle filters, will benefit from it. Current ensemble methods in climate science, such as ensemble Kalman filters, exhibit a linear dependency between the problem size and the ensemble size, while particle filters show an exponential dependency. Nevertheless, with the prospect of massive computing power come challenges such as power consumption and fault-tolerance. The mean-time-between-failures shrinks with the number of components in the system, and it is expected to have failures every few hours at exascale. In this thesis, we explore and develop techniques to protect large ensemble computations from failures. We present novel approaches in differential checkpointing, elastic recovery, fully asynchronous checkpointing, and checkpoint compression. Furthermore, we design and implement a fault-tolerant particle filter with pre-emptive particle prefetching and caching. And finally, we design and implement a framework for the automatic validation and application of lossy compression in ensemble data assimilation. Altogether, we present five contributions in this thesis, where the first two improve state-of-the-art checkpointing techniques, and the last three address the resilience of ensemble computations. The contributions represent stand-alone fault-tolerance techniques, however, they can also be used to improve the properties of each other. For instance, we utilize elastic recovery (2nd contribution) for mitigating resiliency in an online ensemble data assimilation framework (3rd contribution), and we built our validation framework (5th contribution) on top of our particle filter implementation (4th contribution). We further demonstrate that our contributions improve resilience and performance with experiments on various architectures such as Intel, IBM, and ARM processors.Amb l’increment de les capacitats de còmput dels supercomputadors, es poden simular models de sistemes físics encara més detallats, i es poden resoldre problemes de més grandària en qualsevol tipus de sistema numèric. Durant els últims vint anys, el rendiment dels clústers més ràpids ha passat del domini dels teraFLOPS (ASCI RED: 2.3 teraFLOPS) al domini dels pre-exaFLOPS (Fugaku: 442 petaFLOPS), i aviat tindrem el primer supercomputador amb un rendiment màxim que sobrepassa els exaFLOPS (El Capitan: 1.5 exaFLOPS). Les tècniques d’ensemble experimenten un renaixement amb la disponibilitat d’aquestes escales tan extremes. Especialment les tècniques més noves, com els filtres de partícules, se¿n beneficiaran. Els mètodes d’ensemble actuals en climatologia, com els filtres d’ensemble de Kalman, exhibeixen una dependència lineal entre la mida del problema i la mida de l’ensemble, mentre que els filtres de partícules mostren una dependència exponencial. No obstant, juntament amb les oportunitats de poder computar massivament, apareixen desafiaments com l’alt consum energètic i la necessitat de tolerància a errors. El temps de mitjana entre errors es redueix amb el nombre de components del sistema, i s’espera que els errors s’esdevinguin cada poques hores a exaescala. En aquesta tesis, explorem i desenvolupem tècniques per protegir grans càlculs d’ensemble d’errors. Presentem noves tècniques en punts de control diferencials, recuperació elàstica, punts de control totalment asincrònics i compressió de punts de control. A més, dissenyem i implementem un filtre de partícules tolerant a errors amb captació i emmagatzematge en caché de partícules de manera preventiva. I finalment, dissenyem i implementem un marc per la validació automàtica i l’aplicació de compressió amb pèrdua en l’assimilació de dades d’ensemble. En total, en aquesta tesis presentem cinc contribucions, les dues primeres de les quals milloren les tècniques de punts de control més avançades, mentre que les tres restants aborden la resiliència dels càlculs d’ensemble. Les contribucions representen tècniques independents de tolerància a errors; no obstant, també es poden utilitzar per a millorar les propietats de cadascuna. Per exemple, utilitzem la recuperació elàstica (segona contribució) per a mitigar la resiliència en un marc d’assimilació de dades d’ensemble en línia (tercera contribució), i construïm el nostre marc de validació (cinquena contribució) sobre la nostra implementació del filtre de partícules (quarta contribució). A més, demostrem que les nostres contribucions milloren la resiliència i el rendiment amb experiments en diverses arquitectures, com processadors Intel, IBM i ARM.Postprint (published version

Technological requirements for solutions in the conservation and protection of historic monuments and archaeological remains

Executive summary: This Study has discovered many achievements associated with European support for scientific and technological research for the protection and conservation of cultural heritage. The achievements to date are: 1. Creation of an active research community 2. A body of research of unparalleled and enviable international quality and character 3. Ongoing effectiveness of research beyond initial funding 4. Substantial rate of publication 5. Imaginative tools of dissemination and publication 6. Clear spin-offs and contribution to European competitiveness often going outside the European cultural heritage area 7. Contribution to emerging European legislation, for example, air quality management. The Study has also uncovered important research gaps associated with this field that have yet to begin to be investigated. It has also discovered the need for continuing fine scale advancement in areas where researchers have been active for a number of years. The overall picture is that European research in the field of cultural heritage protection must be put on a secure footing if it is to maintain its commanding lead over other regions of the world. This Study concludes that: 1. It would be invidious to attempt to separate basic and applied research in this area of research. Like any other scientific endeavour, this field needs to integrate basic and applied research if it is to continue to thrive. 2. Small, flexible, focused interdisciplinary teams responsive to European needs, must be sustained, promoted and celebrated as models of sustainability and that what is proposed under the European Research Area (ERA) for large and complex research projects, could inflict serious damage on this area of research. 3. Resources cannot be delegated to Member States because of the interdisciplinary nature of cultural heritage and the need for a co-ordinated pan-European perspective across this research that helps to define the essential character of European cultural heritage. National programmes only serve local needs, leading to loss of strategic output, lessening of competitiveness and risk of duplication. 4. A mechanism needs to be created to help researchers working in this field to communicate and exchange information with related sectors such as construction, urban regeneration, land reclamation and agriculture. 5. There is overwhelming agreement over the need for sustainable research funding for cultural heritage and for an iterative process of exchange among researchers, decision-makers and end-users in order to maximize benefits from project inception through to dissemination, audit and review. For all the reasons mentioned above, the most significant recommendation in this Report is the identification of the need for a European Panel on the Application of Science for Cultural Heritage (EPASCH)

Fragmentation and Loss: A GIS View of the Mojave Desert Tortoise Habitat

Landscapes are ever changing or being changed by natural forces or by human activities. The changes, over time, frequently result in more complex and fragmented landscape structures. Much of the fragmentation is due to human activities, primarily roads. Landscape indices, tools that identify and quantify landscape structure, provide statistical analysis of how the landscape is fragmented by roads and what, if any, habitat loss resulting from road-avoidance behavior might be present. The interpretation of the landscape indices can give scientists clues to where limited resources can be directed to preserve the habitat. The desert tortoise habitat was chosen as the subject for a baseline assessment of fragmentation and habitat loss in theMojave Desert. The desert tortoise is highly sensitive to changes in its environment. In 1990, the tortoise was listed as Threatened due to dramatic decreases in its population over only a few decades. The reasons for the listing included deterioration and loss of habitat. The desert tortoise continues to be studied for changes in population that might indicate broader problems for all species in theMojave Desert. This project involved the statistical analysis of the desert tortoise habitat, using Patch Analyst 3.1, a landscape analysis program incorporating landscape indices, ArcView 3.3, and ArcGIS 9.1 to model the desert tortoise habitat and provide a baseline assessment of fragmentation due to roads and potential for habitat loss resulting from road-avoidance behavior in the desert tortoise habitat. Preliminary analysis of the landscape-level statistics suggests that the Mojave Desert is highly fragmented, particularly in the western Mojave Desert of California. Roads, particularly highways and secondary roads impose significant barriers to movement, although how this might affect the desert tortoise, with its small home range, remains to be determined. The evidence of greater road-avoidance distances based on the figures from a von Seckendorff Hoff and Marlowe (2002) study, produced evidence of loss of habitat, especially for near highways and secondary roads. Overall, it appears that the Mojave Desert tortoise habitat is extremely fragmented, with large potential for significant habitat loss resulting from the human need for more roads