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Objective: To investigate if the alternating current impedance spectroscopy (ACIS) technology could be used to monitor remineralization of post-orthodontic white spot lesions (WSLs) after debonding of fixed orthodontic appliances. Material and methods: The study group consisted of 28 adolescents (aged 12–16 years) with at least two WSLs on their maxillary incisors, canines, or first premolars at debonding. Buccal surfaces (n = 194) were visually examined and scored with modified International Caries Detection and Assessment System (ICDAS) criteria and with the CarieScan Pro device by three examiners according to manufactures manual (test method). In addition, 31 surfaces with ICDAS = 0 were monitored by ACIS, serving as controls. Follow-up examinations were carried out after 8 and 16 weeks. Modified ICDAS scores, captured from digital photographs by three independent examiners, served as reference method. Four patients were lost to follow-up. Data were analysed in a mixed statistical model considering systematic effects of visit, tooth and observer, random effects of patients, and visits within patients. Results: Over 50 per cent of all surfaces had marked WSL at baseline and the corresponding values at 8 and 16 weeks were 33 per cent and 22 per cent. The ACIS readings mirrored the visual scores; the baseline estimate (56.3) was significantly decreased after 8 weeks (P < 0.05).The lateral incisors exhibited the highest values whereas the lowest were recorded for the central incisors. Limitations: ICDAS is not the same as a ‘true’ gold standard. The high prevalence of WSL may jeopardize the external validity. Conclusion: The ACIS technology may to some extent be used to monitor the regression of post-orthodontic WSLs. © The Author(s) 2018. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved.

Weedy plants pose a major threat to food security, biodiversity, ecosystem services and consequently to human health and wellbeing. However, many currently used weed management approaches are increasingly unsustainable. To address this knowledge and practice gap, in June 2014, 35 weed and invasion ecologists, weed scientists, evolutionary biologists and social scientists convened a workshop to explore current and future perspectives and approaches in weed ecology and management. A horizon scanning exercise ranked a list of 124 pre-submitted questions to identify a priority list of 30 questions. These questions are discussed under seven themed headings that represent areas for renewed and emerging focus for the disciplines of weed research and practice. The themed areas considered the need for transdisciplinarity, increased adoption of integrated weed management and agroecological approaches, better understanding of weed evolution, climate change, weed invasiveness and finally, disciplinary challenges for weed science. Almost all the challenges identified rested on the need for continued efforts to diversify and integrate agroecological, socio-economic and technological approaches in weed management. These challenges are not newly conceived, though their continued prominence as research priorities highlights an ongoing intransigence that must be addressed through a more system-oriented and transdisciplinary research agenda that seeks an embedded integration of public and private research approaches. This horizon scanning exercise thus set out the building blocks needed for future weed management research and practice; however, the challenge ahead is to identify effective ways in which sufficient research and implementation efforts can be directed towards these needs. Biotechnology and Biological Sciences Research Council [BB/L001489/1, BBS/OS/CP/000001]; USDA Controlling weedy and Invasive Plants program [2013-67013-21306]; Meat and Livestock Australia; NERC Fellowship [NE/I022027/1]; Sociedad Espanola de Malherbologia (SEMh); Grains Research and Development Corporation of Australia Travel Award The workshop organisers would like to express sincere gratitude to the University of Lleida, Spain, for technical support and facilities. The European Weed Research Society generously contributed a grant to the workshop organisers to support attendance of early career researchers (B.B., D.L., J.N., L.H., M.R., M.S., S.H.). P.N. acknowledges the financial support of the Biotechnology and Biological Sciences Research Council (BB/L001489/1 and BBS/OS/CP/000001). J.N.B. acknowledges the USDA Controlling weedy and Invasive Plants program (2013-67013-21306). S.G. received financial support from Meat and Livestock Australia for attendance at the workshop. D.Z. was supported by an NERC Fellowship (NE/I022027/1). B.B. received support from Sociedad Espanola de Malherbologia (SEMh). M.C. was awarded a Grains Research and Development Corporation of Australia Travel Award.

In the year of 2035, the building mass in Denmark has to be CO2 neutral, which puts demands on energy consumption/loose in buildings - new as old. That calls for an innovation of energy optimizations. Due to the strict requirements in new buildings and energy renovation of buildings, it is very obvious to develop alternative methods to optimize energy consumption. PURPOSE - To minimize the linear thermal transmittance between the building shell and a window or a door. - Removes the possibility by thermal bridges and by that removes the conditions of energy loss, condensation, mold and rot, in the construction (joints) between the window or door and the surrounding construction (material). - To make the workflow easier and thereby reducing the construction costs in renovation and new buildings. - The long term idea is to establish standard dimensions and enable recycling of windows and doors. - Fast interim closing of buildings and by that minimizing the construction time.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 1562-1565, SiSim is a continuum model for simulation of Si casting/crystallization and cooling/reheating based upon volume-averaged conservation principles for mass, solute, energy and momentum. The model has been applied to study impurity transport during directional solidification using a coupled description of heat transfer, melt convection and impurity transport. Segregation is described assuming no undercooling, a melting point invariant with respect to composition and linearised binary phase diagrams. A case study of the impact of the flow pattern on the final dopant and impurity distribution in the ingot is presented.

Metadata only record We develop a new conceptual model we call the Resource Pool Diversity Hypothesis (RPDH) aimed at explaining how soil resource pool diversity may mediate competition for soil resources between weeds and crops. The primary tenets of the RPDH are that (i) in plant communities, the intensity of inter-specific competition can depend upon the degree to which niche differentiation and resource partitioning occur among species, (ii) agricultural systems are unique in that management practices, such as crop rotation, source of fertility and weed management, result in inputs to the soil and (iii) these inputs directly or indirectly become soil resource pools from which crops and weeds may partition resources. The RPDH leads to the novel prediction that along a gradient of increasing cropping system diversity, yield loss due to weed-crop competition (i.e. the impact on yield per unit weed density) for soil resources should decrease. Similarly, the degree to which crops and weeds overlap in soil resource niche breadth (which is determined by species-specific functional traits for resource acquisition), will determine the extent to which weed-crop competition weakens as resource pool diversity increases. While there have been no direct tests of the RPDH, we highlight evidence from the agricultural literature that provides strong support for components of the hypothesis. Validation of the RPDH would have important implications across a broad range of cropping systems for the development of management strategies that aim to reduce yield loss impact per unit weed plant density and the fundamental principles of integrated weed management, such as the concepts of weed thresholds and critical periods. (CabAbstracts)

Metadata only record Experiments comparing conventional and organic systems often report similar yields despite substantially higher weed abundance in the organic systems. A potential explanation for this observation is that weed-crop competition relationships differ between the two types of systems. We analysed weed and crop yield data from the Rodale Institute Farming Systems Trial (FST), which provides a unique 27-year dataset of a conventional (CNV) and two organic [manure (MNR) and legume (LEG)] soyabean (Glycine max (L.) Merr.) and maize (Zea mays L.) cropping systems. Average soyabean yields were similar between the MNR and CNV systems and only slightly reduced in the LEG system, whereas average maize yields did not differ among systems despite the two organic systems having more than four and six times greater weed biomass in soyabean and maize respectively. Plot-level weed biomass-crop yield relationships indicated that weed-crop competition differed between the two organic and CNV systems in maize, and was strongest in the CNV system, intermediate in the LEG system and weakest in the MNR system. These results suggest that organic cropping systems may be able to tolerate a greater abundance of weeds compared to conventional systems and that fertility management within organic systems may influence weed-crop competition. (CabAbstracts)