Drones and Digital Photogrammetry: From Classifications to Continuums for Monitoring River Habitat and Hydromorphology

Recently, we have gained the opportunity to obtain very high-resolution imagery and topographic data of rivers using drones and novel digital photogrammetric processing techniques. The high-resolution outputs from this method are unprecedented, and provide the opportunity to move beyond river habitat classification systems, and work directly with spatially explicit continuums of data. Traditionally, classification systems have formed the backbone of physical river habitat monitoring for their ease of use, rapidity, cost efficiency, and direct comparability. Yet such classifications fail to characterize the detailed heterogeneity of habitat, especially those features which are small or marginal. Drones and digital photogrammetry now provide an alternative approach for monitoring river habitat and hydromorphology, which we review here using two case studies. First, we demonstrate the classification of river habitat using drone imagery acquired in 2012 of a 120 m section of the San Pedro River in Chile, which was at the technological limits of what could be achieved at that time. Second, we review how continuums of data can be acquired, using drone imagery acquired in 2016 from the River Teme in Herefordshire, England. We investigate the precision and accuracy of these data continuums, highlight key current challenges, and review current best practices of data collection, processing, and management. We encourage further quantitative testing and field applications. If current difficulties can be overcome, these continuums of geomorphic and hydraulic information hold great potential for providing new opportunities for understanding river systems to the benefit of both river science and management

Evaluation of corrective measures implemented for the preventive conservation of fresco paintings in Ariadne s house (Pompeii, Italy)

BACKGROUND: A microclimate monitoring study was conducted in 2008 aimed at assessing the conservation risks affecting the valuable wall paintings decorating Ariadne s House (Pompeii, Italy). It was found that thermohygrometric conditions were very unfavorable for the conservation of frescoes. As a result, it was decided to implement corrective measures, and the transparent polycarbonate sheets covering three rooms (one of them delimited by four walls and the others composed of three walls) were replaced by opaque roofs. In order to examine the effectiveness of this measure, the same monitoring system comprised by 26 thermohygrometric probes was installed again in summer 2010. Data recorded in 2008 and 2010 were compared. RESULTS: Microclimate conditions were also monitored in a control room with the same roof in both years. The average temperature in this room was lower in 2010, and it was decided to consider a time frame of 18 summer days with the same mean temperature in both years. In the rooms with three walls, the statistical analysis revealed that the diurnal maximum temperature decreased about 3.5 ºC due to the roof change, and the minimum temperature increased 0.5 ºC. As a result, the daily thermohygrometric variations resulted less pronounced in 2010, with a reduction of approximately 4 ºC, which is favorable for the preservation of mural paintings. In the room with four walls, the daily fluctuations also decreased about 4 ºC. Based on the results, other alternative actions are discussed aimed at improving the conservation conditions of wall paintings. CONCLUSIONS: The roof change has reduced the most unfavorable thermohygrometric conditions affecting the mural paintings, but additional actions should be adopted for a long term preservation of Pompeian frescoes.This work was partially supported by the Spanish Government (Ministerio de Ciencia e Innovacion) under projects HAR2010-21944-C02-01 and HAR2010-21944-C02-02.Merello Giménez, P.; García Diego, FJ.; Zarzo Castelló, M. (2013). Evaluation of corrective measures implemented for the preventive conservation of fresco paintings in Ariadne s house (Pompeii, Italy). Chemistry Central Journal. 7(1):87-87. doi:10.1186/1752-153X-7-87S878771DELOSRIOS, A., CAMARA, B., GARCIADELCURA, M., RICO, V., GALVAN, V., & ASCASO, C. (2009). Deteriorating effects of lichen and microbial colonization of carbonate building rocks in the Romanesque churches of Segovia (Spain). Science of The Total Environment, 407(3), 1123-1134. doi:10.1016/j.scitotenv.2008.09.042Nava, S., Becherini, F., Bernardi, A., Bonazza, A., Chiari, M., García-Orellana, I., … Vecchi, R. (2010). An integrated approach to assess air pollution threats to cultural heritage in a semi-confined environment: The case study of Michelozzo’s Courtyard in Florence (Italy). Science of The Total Environment, 408(6), 1403-1413. doi:10.1016/j.scitotenv.2009.07.03

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

Physical Weathering

Living reference work entry First Online: 13 February 2017 Synonyms: Disintegration; Fragmentation; Mechanical weathering; Slaking Definition: Physical weathering of rocks consists of their physical disintegration, without chemical weathering, by several physical actions such as (a) significant diurnal and/or seasonal thermal variations, (b) expansion and fracturing of rock due either to stress relief or increase of pressure in rock pores and fissures by expansion volume associated with water freezing, and (c) mechanical actions of several weathering agents such as water flow, glaciers, wind, living organisms (e.g., roots of trees, cavities made by rodents), and the growth of poorly soluble salts, in rock pores, either by crystallization pressure, such as hydration pressure or by differential thermal expansion. These are of fundamental importance in the breakdown and fragmentation of rocks. Introduction:The weathering of rocks is an important geological phenomenon because it leads to the formation of soils (whether residual or sedimentary),... This is a preview of subscription content, log in to check access Copyright information © Springer International Publishing AG 201