Choice and constraint in flood hazard mitigation: the environmental attitudes of floodplain residents and engineers

This research examines the importance of environmental factors in the choice, promotion and implementation of flood defence schemes in England and Wales. It focuses on the attitudes of National Rivers Authority (NRA) engineers and floodplain residents to low-frequency flood events and investigates the role of NRA engineers in influencing, the choices of floodplain residents. The theoretical focus includes an examination of the appropriateness of the dominant (North American) hazards research paradigm as an explanatory model in the British context and the development of a conceptual model applicable to this socio-political and cultural milieu. The research extends existing, primarily quantitative, research designs to include more qualitative approaches which provide descriptive richness and context beyond that afforded by quantitative data alone. The quantitative and qualitative studies of floodplain residents show environmental factors to be an important influence on their attitudes to proposals for flood hazard mitigation and to existing flood defence schemes. This is conceptualised as a 'risk-environment trade-off. The case studies of floodplain residents further identify an unmet information need concerning both flood risk and flood defence. The qualitative study of NRA engineers highlights the differences in perception and attitude between engineers and residents to flood risk, flood defence, public consultation and environmental factors. It underlines the complexity of the interactions which occur between individual, institutional and societal levels. The research concludes that the dominant paradigm model is inappropriately focused at the individual level and does not take sufficient account of institutional and structural influences. Furthermore, the concentration on choice rather than constraint ignores the social conflict and self-interest of actors in the decision-making environment. The research suggests that a systems approach is inadequate for dealing with the complexities of flood hazard mitigation

Observation of O+ 4P-4D0 lines in proton aurora over Svalbard

Spectra of a proton aurora event show lines of O+ 4P-4D0 multiplet (4639–4696 Å) enhanced relative to the N2 +1N(0,2) compared to normal electron aurora. Conjugate satellite particle measurements are used as input to electron and proton transport models, to show that p/H precipitation is the dominant source of both the O+ and N2 +1N emissions. The emission cross-section of the multiplet in p collisions with O and O2 estimated from published work does not explain the observed O+ brightness, suggesting a higher emission cross-section for low energy p impact on O

Razlike u kemijskom sastavu i antioksidacijskoj sposobnosti različitih genotipova himalajske maslinice (Elaeagnus umbellate Thunb.)

Fruit from six genotypes of autumn olive (Elaeagnus umbellate Thunb.); Brilliant Rose, Delightful, Jewel, Natural 1, Natural 2 and Sweet N Tart; were evaluated for fruit quality, phenolic content, carotenoids, antioxidants, antioxidant capacity, and antioxidant enzyme activity. The fruit soluble solids content (SSC), titratable acids (TA), total carotenoids, and total phenolic content varied with genotypes. Soluble solids content (SSC) in six genotypes of autumn olive ranged from 10.6 to 18.4 %, while titratable acids ranged from 0.79 to 1.29 %. Jewel had the highest SSC and Sweet N Tart had the highest TA. Fructose and glucose were the two predominant sugars, and malic acid was the predominant organic acid found in autumn olive fruit. Jewel and Sweet N Tart cultivars had the highest sugar and organic acid content among the six genotypes. Autumn olive had potent free radical scavenging activities for 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH·), 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS+·), peroxyl radical (ROO·), superoxide radicals (O2–·), hydroxyl radicals (·OH), and singlet oxygen (1O2). Autumn olive also had high activities of antioxidant enzymes including glutathione peroxidase (GHS-POD), glutathione reductase (GR), superoxide dismutase (SOD), ascorbate peroxidase (AsA-POD), dehydroascorbate reductase (DHAR), and monodehydroascorbate reductase (MDAR). Among the six genotypes, Brilliant Rose and Jewel had the highest levels of antioxidants and antioxidant enzyme activity.Ocijenjena je kakvoća plodova, udio fenola, karotenoida, antioksidansa, te antioksidativna sposobnost i aktivnost enzima u plodovima šest genotipova himalajske maslinice (Elaeagnus umbellate Thunb.); Brilliant Rose, Delightful, Jewel, Natural 1, Natural 2 i Sweet N Tart. Udio topljivih tvari, titracijska kiselost, te udio ukupnih karotenoida i fenola ovisio je o genotipu ploda. Udio topljivih tvari iznosio je od 10,6 do 18,4 %, dok je titracijska kiselost bila od 0,79 do 1,29 %. Najviše topljivih tvari sadržavao je genotip Jewel, a najveću titracijsku kiselost imao je genotip Sweet N Tart. U plodu himalajske maslinice najveći je udio fruktoze i glukoze, dok je jabučna kiselina dominantna organska kiselina. Kultivari Jewel i Sweet N Tart imaju najviše šećera i organskih kiselina. Himalajska maslinica sadrži spojeve koji imaju izrazitu sposobnost uklanjanja slobodnih radikala poput 2,2-di(4-tert-oktilfenil)-1-pikrilhidrazil (DPPH˙), diamonijeve soli 2,2\u27-azinobis(3-etilbenzotiazolin-6-sulfonske kiseline) (ABTS˙+), peroksilnog radikala (ROO˙), superoksidnog radikala (O2˙-) i hidroksilnog radikala (˙OH) te singletnog kisika (¹O2). U plodovima himalajske maslinice aktivni su i antioksidativni enzimi, kao što su glutation-peroksidaza, glutation-reduktaza, superoksid-dismutaza, askorbat-peroksidaza, dehidroaskorbat-reduktaza i monodehidroaskorbat-reduktaza. Od šest ispitanih genotipova Brilliant Rose i Jewel imali su najveći udio antioksidansa i najjaču antioksidativnu enzimsku aktivnost

The Effects of Varying Composition and Build Direction on Direct Metal Deposition Fabricated Inconel 718

Inconel 718 (IN718) is a popular wrought superalloy, and is currently being investigated for additive manufacturing (AM) applications in the aerospace industry. However, overaging and the presence of microcracks have caused a significant reduction in properties. The purpose of this study is to meet or exceed the mechanical properties of wrought IN718 by varying the composition and build direction of the AM alloy. Alternative compositions were selected with Oerlilon Metco’s Rapid Alloy Development (RAD) software, and differ in niobium content, which increases the fraction of the primary strengthening phase (γʺ). Direct metal deposition (DMD) was used to fabricate the samples, which then underwent a heat treatment to precipitate γʺ. Tensile testing, metallography, and scanning electron microscopy (SEM) were performed on the samples. Tensile testing found that the AM samples could exceed wrought strength with the appropriate composition and build direction. The horizontal build containing the highest niobium percentage achieved an average yield strength of 1400 MPa, higher than the 1218 MPa for the wrought. Samples in the horizontal build direction were consistently stronger than vertical alternatives due to their anisotropic grain morphology. Despite comparable strength, AM samples of all compositions had significantly reduced ductility with an average range of 1-3% elongation compared to an average of 21% for the wrought samples. Microstructural analysis revealed dendritic structures and cracks between print layers in the AM samples, which contributed to this reduction in ductility

20 years of Radical Disaster Interpretations: reflections and aspirations (RADIX @ 20!). Conversation on disasters: deconstructed on 13 October 2021

Purpose: This conversation presents the reflections from five prominent disaster scholars and practitioners on the purpose of Radix – the Radical Disaster Interpretations network – as the authors celebrate its 20th anniversary. / Design/methodology/approach: This paper is based on the conversations that took place on Disasters: Deconstructed Podcast livestream on the 13th October 2021. / Findings: The conversation reflects on personal and professional journeys in disaster studies over the past 20 years and on what needs changing in order to make disaster interpretations more radical. / Originality/value: The conversation contributes to the ongoing discussions around explorations of radical pathways for understanding and preventing disasters

Vinylidene Homologation of Boronic Esters and its Application to the Synthesis of the Proposed Structure of Machillene

Alkenyl boronic esters are important reagents in organic synthesis. Herein, we report that these valuable products can be accessed by the homologation of boronic esters with lithiated epoxysilanes. Aliphatic and electron-rich aromatic boronic esters provided vinylidene boronic esters in moderate to high yields, while electron-deficient aromatic and vinyl boronic esters were found to give the corresponding vinyl silane products. Through DFT calculations, this divergence in mechanistic pathway has been rationalized by considering the stabilization of negative charge in the C-Si and C-B bond breaking transition states. This vinylidene homologation was used in a short six-step stereoselective synthesis of the proposed structure of machillene, however, synthetic and reported data were found to be inconsistent.</p

Glacier Peak and the Chocolate Factory: Recurring debris flows from the eastern flank of Glacier Peak stratovolcano, North Cascades, Washington State, USA

Alpine mass wasting events can have wide ranging impacts that extend past their headwater origins reaching down to lowland population centers. The Suiattle River, which drains the eastern flank of Glacier Peak in the North Cascades of Washington State, is a dominant contributor of suspended sediment in the region. Normalized for drainage area, the Suiattle River supplies more suspended sediment than nearly any other river in the region and more than twice as much as the White Chuck River, which drains the western flank of the volcano. Despite its known importance to the regional sediment budget, the specific geomorphic drivers of the anomalous sediment load on the Suiattle have received relatively little attention in the literature. In this study, I build on previous work to explore the magnitude, timing, triggering mechanisms, and the spatial distribution of sediment loading events in the Suiattle River Basin. My historical analysis shows that major debris flow activity initiated in the late-1930s, with a total of nine historic debris flows since then (RI = 9.3 years). One previously unreported circa late-1940s debris flow was identified from reanalysis of dendrochronology (Slaughter, 2004) and historical aerial imagery. From topographic differencing, I placed a minimum bound of ~4.9 M m3 (±0.6 M m3) on the material incised from the most recent valley filling debris flow deposits. Historical accounts suggest that major debris flows happen at the hottest times of the year in the absence of precipitation, with two eyewitness accounts of debris flows triggered by glacial outburst floods. Historical photos, remote sensing, and field measurements of terrace heights suggest that incision into historic debris flow deposits occurs soon after deposition and tapers after the first few years. To examine smaller more recent debris flows, I created a framework to automatically extract debris flow timing, duration, and magnitude from USGS turbidity and discharge data over the period 2011 to 2020. I identified 28 individual debris flow events that occurred in every year in the record. To evaluate triggering mechanisms, I calculated prior day maximum temperature anomalies for all non-debris flow days and for days when a debris flow started. Debris flow start days were shown to be statistically warmer than non-debris flow days (mean of -0.21 °C and 2.48 °C, respectively; ks test, dm = 0.314, p = 0.007). This suggests that minor debris flows are triggered by high temperatures and, like the historical major debris flows, points to glacier outburst floods as the primary initiation process. I estimate suspended sediment loads attributable to minor debris flows, anomalous sediment flushing events following debris flows, and suspended sediment loads outside of these categories. Together debris flows and flushing account for ~21% of the mean annual load on the Suiattle. At Glacier Peak, Chocolate Glacier is unique. Its high propensity for glacier outburst floods makes it the dominant source of debris flows and suspended sediment, vastly outweighing contributions from other glaciers on the mountain. The frequency and magnitude of debris flows from Chocolate Glacier bare similarities to South Tahoma Glacier at Mount Rainier. Combined, my findings show that debris flows deliver large quantities of sediment to the mainstem river at both annual and decadal timescales. This work is a step toward understanding how sediment supplied from alpine mass wasting events shapes downstream geomorphic processes. My findings have implications for how ongoing climate change may alter cascading hazards in these systems