Examining rhyolite lava flow dynamics through photo-based 3D reconstructions of the 2011–2012 lava flowfield at Cordón-Caulle, Chile

During the 2011–2012 eruption at Cordón-Caulle, Chile, an extensive rhyolitic flowfield was created (in excess of 0.5 km3 in volume), affording a unique opportunity to characterise rhyolitic lava advance. In 2012 and 2013, we acquired approximately 2500 digital photographs of active flowfronts on the north and east of the flowfield. These images were processed into three-dimensional point clouds using structure-from-motion and multi-view stereo (SfM–MVS) freeware, from which digital elevation models were derived. Sequential elevation models—separated by intervals of three hours, six days, and one year—were used to reconstruct spatial distributions of lava velocity and depth, and estimate rheological parameters. Three-dimensional reconstructions of flowfronts indicate that lateral extension of the rubbly, 'a'ā-like flowfield was accompanied by vertical inflation, which differed both spatially and temporally as a function of the underlying topography and localised supply of lava beneath the cooled upper carapace. Compressive processes also drove the formation of extensive surface ridges across the flowfield. Continued evolution of the flowfield resulted in the development of a compound flowfield morphology fed by iterative emplacement of breakout lobes. The thermal evolution of flow units was modelled using a one-dimensional finite difference method, which indicated prolonged residence of magma above its glass transition across the flowfield. We compare the estimated apparent viscosity (1.21–4.03 × 1010 Pa s) of a breakout lobe, based on its advance rate over a known slope, with plausible lava viscosities from published non-Arrhenian temperature–viscosity models and accounting for crystallinity (~ 50 vol.%). There is an excellent correspondence between viscosity estimates when the lava temperature is taken to be magmatic, despite the breakout being located > 3 km from the vent, and advancing approximately nine months after vent effusion ceased. This indicates the remarkably effective insulation of the lava flow interior, providing scope for significant evolution of rhyolitic flow fields long after effusive activity has ceased

Examining rhyolite lava flow dynamics through photo-based 3D reconstructions of the 2011–2012 lava flowfield at Cordón-Caulle, Chile

During the 2011–2012 eruption at Cordón-Caulle, Chile, an extensive rhyolitic flowfield was created (in excess of 0.5 km3 in volume), affording a unique opportunity to characterise rhyolitic lava advance. In 2012 and 2013, we acquired approximately 2500 digital photographs of active flowfronts on the north and east of the flowfield. These images were processed into three-dimensional point clouds using structure-from-motion and multi-view stereo (SfM–MVS) freeware, from which digital elevation models were derived. Sequential elevation models—separated by intervals of three hours, six days, and one year—were used to reconstruct spatial distributions of lava velocity and depth, and estimate rheological parameters. Three-dimensional reconstructions of flowfronts indicate that lateral extension of the rubbly, 'a'ā-like flowfield was accompanied by vertical inflation, which differed both spatially and temporally as a function of the underlying topography and localised supply of lava beneath the cooled upper carapace. Compressive processes also drove the formation of extensive surface ridges across the flowfield. Continued evolution of the flowfield resulted in the development of a compound flowfield morphology fed by iterative emplacement of breakout lobes. The thermal evolution of flow units was modelled using a one-dimensional finite difference method, which indicated prolonged residence of magma above its glass transition across the flowfield. We compare the estimated apparent viscosity (1.21–4.03 × 1010 Pa s) of a breakout lobe, based on its advance rate over a known slope, with plausible lava viscosities from published non-Arrhenian temperature–viscosity models and accounting for crystallinity (~ 50 vol.%). There is an excellent correspondence between viscosity estimates when the lava temperature is taken to be magmatic, despite the breakout being located > 3 km from the vent, and advancing approximately nine months after vent effusion ceased. This indicates the remarkably effective insulation of the lava flow interior, providing scope for significant evolution of rhyolitic flow fields long after effusive activity has ceased

Water sharing for the environment and agriculture in the Broken catchment

The Commonwealth of Australia Water Act 2007 changed the priority for water use in the Murray-Darling Basin (MDB) to first ensure environmentally sustainable levels of extraction and then to maximise net economic returns to the community from water use. The Murray- Darling Basin Authority (MDBA) is expected to deliver a draft Basin Plan in 2011 providing a framework for future water planning. The Plan will include Sustainable Diversion Limits (SDLs) which define water diversions for consumption while maintaining environmental assets and ecosystem functions. The 2009 MDBA Concept Statement acknowledged that in some areas less information is available to determine the SDLs. The 2010 MDBA Guide to the Basin Plan proposed SDLs reducing the current long-term average surface water diversions to between 25 and 34% for the Goulburn-Broken region. Representative farm-level models of irrigated dairy, horticulture and viticulture, and dryland broadacre, industries were developed to determine the likely impacts on farm income and farm enterprise mix if the price and quantity of irrigation water changes. Water for ecological benefits and ecosystem functioning was determined for a range of river health levels using a bottom-up approach identifying flow requirements for fish, riparian vegetation, invertebrates, and geomorphic and nutrient processes. A novel part of the analysis is the conjunctive use of water for both purposes, e.g. wetland filling and then pumping for irrigation. The linkages between changed land use and surface/ground water outcomes are assessed using a Catchment Analysis Tool. An experimental design of different proportions of water going to the environment and consumptive uses showed potential trade-offs between agricultural, environmental and surface/ground water outcomes. These trade-offs were examined to assess the impact of alternative water management on catchment welfare, and provide information about setting SDLs.Water sharing, environment, agriculture, Murray-Darling Basin, Broken catchment, Resource /Energy Economics and Policy, Q18, Q25, Q28,

Supporting work-based mentors; finding solutions to the current issues that surround mentorship in Foundation Degrees

The aim of this study was to identify the challenges of mentoring within the Foundation Degree arena, by exploring collected data and using the identified gaps found in literature. Whilst there was no newly defined evidence, there was a new approach and a clearer understanding of the issues that surround mentoring within Foundation Degrees and therein the opportunity to affect structural and valuable change to the support process for both mentor and vicariously the mentee. A mixed method approach was employed to collect and analyse data. All participants were involved in mentorship within a Foundation Degree programme. Initially a qualitative approach was used in the form of focus groups; they defined perceptions of mentorship locally. There were three focus groups, university staff, Foundation Degree students and nursing mentors. The initial comparisons helped fuel the debate and provided a deeper comprehension, into the identified issues that surrounded Foundation Degree mentorship. Through the focus groups key themes were identified ‘Participants’ definition of mentorship’, ‘Mentorship expectation ‘Responsibilities and support’. Detecting these themes focused the study and helped to identify the role of Foundation Degree mentors in areas such as specific mentorship characteristics and components of the role. The themes were then used to formulate a questionnaire. One hundred participants contributed to the findings, demonstrating key elements, such as assessments, knowledge, relationships and skills. The study was able to identify key areas to improve mentorship support mechanisms within Foundation Degrees. The findings do allow the opportunity to develop identifiable structure which gives the Foundation Degree mentorship process direction and therefore a more credible chance of effectiveness. The links and involvement of Higher Educational institutions, employers and students creates a more cohesive approach and adds to the success of the improved understanding and outcomes highlighted in the role of mentorship

Characterisation of bone tissue using coherently scattered X-ray photons

An energy dispersive x-ray diffractometer was designed and built to measure bone mineral density in the trabecular region of the bone and to assess the suitability of the technique as a clinical in-vivo method. Trabecular bone has a higher turnover rate than that of cortical bone, and to detect excessive bone mass loss, with the prevention of osteoporosis in mind, it would be advantageous to be able to measure trabecular bone mineral density in isolation from cortical bone density. At present the only method capable of achieving this in-vivo is quantitative computerised tomography. Initially measurements were made of trabecular bone mineral density on dry excised bone samples consisting of femurs, vertebrae and radii. These measurements were compared to measurements made using dual energy x-ray absorptiometry (DEXA) and photodensitometry techniques. The energy dispersive x-ray diffraction (EDXRD) measurements were the most accurate when correlated to the actual trabecular densities of the femur and vertebrae with correlation coefficients of r=0.84 and r=0.92 respectively. This compares with r=0.64 and r=0.74 for the DEXA measurements and r=0.77 and r=0.85 for the photodensitometry measurements. For the radii samples the correlation coefficients for all the methods were approximately the same at r=0.75. In-vivo measurements were simulated using a specially designed phantom. The results were analysed using multivariate calibration techniques and the radiation dose to the patient estimated using thermoluminescent dosimetry (TLD). Two main clinical sites were targeted, the calcaneus (heel) and the radius (forearm). It was found that the technique was capable of producing results with the required accuracy and precision (approximately 1[percent] of peak bone mass) but the radiation dose to the patient was high compared to other diagnostic radiographic procedures. The calcaneus measurements produced an effective dose of 270 [mu]Sv. for an accuracy of between 1[percent] and 2[percent] fractional bone mass loss, and the radius measurement resulted in an effective dose of 3.3 mSv. for an accuracy of approximately 2[percent] fractional bone mass loss. Measurements were made on recently excised femoral heads from total hip replacements, with 5 cm of tissue equivalent material. Predictions of bone mineral density were made from a calibration model created using phantom measurements. The predictions were compared to CT numbers obtained from QCT measurements and the correlation coefficient was calculated to be 0.94 significant to the 0.1 [percent] level. It is concluded that EDXRD is a technique that, with suggested refinements, has the potential to be able to make clinical measurements giving good accuracy and precision at an acceptable radiation dose to the patient

To the Nadir and Back: The Executive Branch of the Royal Navy 1918-1939

The Royal Navy, and especially its leadership, is perceived to have performed poorly in the First World War and its officers have been described as being automatons who only came alive when directed by superiors. By contrast in the Second World War the Royal Navy and its officers are seen as having ‘done well,’ displaying flair and initiative. There does not appear to have been any attempt to look in any detail at what, if anything, changed in the twenty years between the wars to explain the perceived improvement. This thesis critically examines the executive branch of the Royal Navy, and contends that the navy adapted and modified the training of its officers to meet whatever was required of them; when they were required to passively obey orders as in the Grand Fleet of the First World War, they had been trained for that eventuality, when to show initiative likewise. During the 1920s the officer corps was mismanaged and morale and motivation suffered badly. The influence of the Admiralty civil service, the repository of institutional memory, which managed junior officers’ careers, was conservative and resistant to change. Changes in training both before and after the mutiny at Invergordon (September 1931) brought the officer corps up to date and set it on track for its outstanding performance in the next war, in particular recognising that leadership was not an innate class based ability, but had to be taught and developed. However, the navy had since the latter part of the nineteenth century changed the emphasis of officer’s career paths; specialist training was seen as the ‘route to the top’ and command was downgraded as a necessary part of an officer’s career development. It was only during the latter part of Second World War that having exercised command at sea was recognised as being an important part of an officer’s experience. The thesis also addresses the ‘RNVR myth’ that the Royal Navy was only able to prosecute the Second World War successfully because of an influx of well educated temporary officers and that they were the major driving force. This thesis has been largely based on primary sources, including personnel records which have not been studied before and have been examined in such a way as to allow statistical analysis

Willingness to Communicate

この論文は,ピーター・マッキンタイヤ博士が2005年春に東京で行ったセミナーでの発表に対する返答である。マッキンタイヤ博士は,コミュニケートする意思を持つ学生を育てることに失敗した言語プログラムはすべて失敗に終わったと述べている。「コミュニケートする意思」の定義は,学習している言語でコミュニケーションを取る意思のある学生のことである。私はこの論文でマッキンタイヤ博士の発表について述べ,ここ日本で我々の多くが直面する教育状況についても述べたい。目標は素晴らしいが,ヨーロッパや北米以外の文化を扱うときは不可能かも知れない。マッキンタイヤ博士はフランス語イマージョンプログラムが正しいフランス語話者を育てていないことで批判を受けているカナダの状況に取り組んだ。マッキンタイヤ博士は学生にコミュニケートする意思があり失敗ではないと主張し,プログラムを弁護する立場にある。これは40年以上激しく繰り広げられてきた正確さと流暢さとの争いの続きかも知れない。This paper is a response to a statement made by Dr. Peter Maclntyre at his seminar in Tokyo in the spring of 2005. Dr. Maclntyre said that any language program that failed to produce students who were willing to communicate was a failed program. "Willingness to communicate" is defined as students who are willing to initiate communication in the language that they are studying. I address the statement and try to put into context as far as the teaching context in which many of us face here in Japan. Though a wonderful goal it might not be possible when dealing with cultures outside Europe or North America. Dr. Maclntyre was of addressing the Canadian situation where the French Immersion program has been under attack for not producing more accurate speakers of French. Dr. Maclntyre\u27s position defends the program by claiming that the students are willing to communicate and therefore it is not a failed program. This might just be a continuation of the battle of accuracy over fluency which has been raging in the field for more than 40 years

Dmp1 Promoter-Driven Diphtheria Toxin Receptor Transgene Expression Directs Unforeseen Effects in Multiple Tissues

Mice harbouring a dentin matrix protein 1 (Dmp1) promoter-driven human diphtheria toxin (DT) receptor (HDTR) transgene (Tg) have recently been used to attain targeted ablation of osteocytes by diphtheria toxin (DT) treatment in order to define osteocyte function. Use of these Tg mice has asserted mechano- and novel paracrine regulatory osteocyte functions. To explore osteocyte roles fully, we sought to confirm the selectivity of DT effects in these transgenic mice. However, our findings revealed incomplete DT-induced osteocyte ablation, prevalent HDTR misexpression, as well as more prominent histopathological DT-induced changes in multiple organs in Tg than in wild-type (WT) littermate mice. Mechanistic evidence for DT action, via prominent regulation of phosphorylation status of elongation factor-2 (EF-2), was also found in many non-skeletal tissues in Tg mice; indicative of direct “off-target” DT action. Finally, very rapid deterioration in health and welfare status in response to DT treatment was observed in these Tg when compared to WT control mice. Together, these data lead us to conclude that alternative models for osteocyte ablation should be sought and caution be exercised when drawing conclusions from experiments using these Tg mice alone

Impact of facial conformation on canine health: Brachycephalic Obstructive Airway Syndrome

The domestic dog may be the most morphologically diverse terrestrial mammalian species known to man; pedigree dogs are artificially selected for extreme aesthetics dictated by formal Breed Standards, and breed-related disorders linked to conformation are ubiquitous and diverse. Brachycephaly–foreshortening of the facial skeleton–is a discrete mutation that has been selected for in many popular dog breeds e.g. the Bulldog, Pug, and French Bulldog. A chronic, debilitating respiratory syndrome, whereby soft tissue blocks the airways, predominantly affects dogs with this conformation, and thus is labelled Brachycephalic Obstructive Airway Syndrome (BOAS). Despite the name of the syndrome, scientific evidence quantitatively linking brachycephaly with BOAS is lacking, but it could aid efforts to select for healthier conformations. Here we show, in (1) an exploratory study of 700 dogs of diverse breeds and conformations, and (2) a confirmatory study of 154 brachycephalic dogs, that BOAS risk increases sharply in a non-linear manner as relative muzzle length shortens. BOAS only occurred in dogs whose muzzles comprised less than half their cranial lengths. Thicker neck girths also increased BOAS risk in both populations: a risk factor for human sleep apnoea and not previously realised in dogs; and obesity was found to further increase BOAS risk. This study provides evidence that breeding for brachycephaly leads to an increased risk of BOAS in dogs, with risk increasing as the morphology becomes more exaggerated. As such, dog breeders and buyers should be aware of this risk when selecting dogs, and breeding organisations should actively discourage exaggeration of this high-risk conformation in breed standards and the show ring

Feedback in surgical education

Introduction: The positive effect of feedback has long been recognized in surgical education. Surgical educators convey feedback to improve the performance of the surgical trainees. We aimed to review the scientific classification and application of feedback in surgical education, and to propose possible future directions for research.Methods: A literature search was performed using Pubmed, OVID, CINAHL, Web of science, EMBASE, ERIC database and Google Scholar. The following search terms were used: 'feedback', 'feedback in medical education', 'feedback in medical training' and 'feedback in surgery'. The search was limited to articles in English.Results: From 1157 citations, 12 books and 43 articles met the inclusion criteria and were selected for this review.Conclusion: Feedback comes in a variety of types and is an essential tool for learning and developing performance in surgical education. Different methods of feedback application are evolving and future work needs to concentrate on the value of each method as well as the role of new technologies in surgical education.</p