Influence of geometry on eruptive behaviour of magma reservoirs

2021 ◽  
Author(s):  
Martin Letourneur ◽  
John O'Sullivan ◽  
Darren Gravley ◽  
Guilherme Gualda ◽  
David Dempsey
Keyword(s):  
Aspect Ratio ◽  
Rock Properties ◽  
Magma Source ◽  
Geothermal System ◽  
Limiting Factor ◽  
Perfect Mixing ◽  
The One ◽  
The Right ◽  
External Stimuli ◽  
Eruptive Behaviour

<p>All active polygenetic volcanoes erupt magma sourced from a shallow crustal reservoir.  Those chambers are complex entities that act as a collector of magma originating from deeper crustal sources. The geometry of those active storage systems depends on the rheology of the magma and on the rock properties of the host. Studying how the geometry influences the eruptive behaviour of a magma chamber has implications for our understanding of volcanic hazard.<br>We introduced a simple model where a magma reservoir is cooled by an overlying geothermal system and recharged by a deeper magma source. The geometry of the chamber is defined by its volume and aspect ratio. The model tracked changes in pressure, mixture enthalpy and composition, and implemented parameterisations of eruption, hydrothermal cooling, viscoelastic relaxation, and volatile leakage. The thermodynamic properties of the melt, crystals and water were computed using rhyolite-MELTS.<br>A large number of simulations sweeping our parameter space gave us insight into how the different magmatic processes trade off with respect to the geometry of the inclusion. An example of the complex control of geometry on the eruptive behaviour can be made regarding cooling and the effective compressibility of an ellipsoidal inclusion. On the one hand, a larger aspect ratio will favor eruptibility by offering a larger area for cooling therefore increasing the exsolution of water and pressure build up. On the other hand, a larger aspect ratio will work against eruptibility by decreasing the compressibility making it harder to build overpressures within the chamber. We found that a specific geometry is required in order for a chamber to erupt without any external stimuli (such as a large recharge event).<br>A limiting factor of our model is the assumption of a perfect mixing. Whereas, in reality, we would expect recharge, cooling and leakage to occur within specific regions of the chamber. In a model where mixing is not considered perfect, those processes would be a source of heterogeneity. We could conjecture that under the right conditions, eruptible regions would appear within the chamber. A model focusing more on the flows within the chamber might be able to give additional insights on the eruptive behaviour of magma chambers.</p>

Mechanisms of Resource Curse and Economic Policy

2007 ◽  
pp. 4-27 ◽  
Author(s):  
V. Polterovich ◽  
V. Popov ◽  
A. Tonis
Keyword(s):  
Real Exchange Rates ◽  
Resource Curse ◽  
Budget Deficits ◽  
Resource Abundance ◽  
Fuel Prices ◽  
Use Of Resources ◽  
Resource Wealth ◽  
The One ◽  
The Right ◽  
Rich Countries

This paper compares various mechanisms of resource curse leading to a potentially inefficient use of resources; it is demonstrated that each of these mechanisms is associated with market imperfections and can be "corrected" with appropriate government policies. Empirical evidence seems to suggest that resource abundant countries have on average lower budget deficits and inflation, and higher foreign exchange reserves. Besides, lower domestic fuel prices that are typical for resource rich countries have a positive effect on long-term growth even though they are associated with losses resulting from higher energy consumption. On top of that resource abundance allows to reduce income inequalities. So, on the one hand, resource wealth turns out to be conducive to growth, especially in countries with strong institutions. However, on the other hand, resource abundance leads to corruption of institutions and to overvalued real exchange rates. On balance, there is no solid evidence that resource abundant countries grow more slowly than the others, but there is evidence that they grow more slowly than could have grown with the right policies and institutions.

Challenges of Media Education Standards in Georgia

2017 ◽  
Vol 2 (2) ◽  
Author(s):  
Marine Vekua
Keyword(s):  
Working Conditions ◽  
Teaching Methods ◽  
International Standards ◽  
The Other ◽  
Historical Background ◽  
Journalism Education ◽  
Education Standards ◽  
Modern Media ◽  
The One ◽  
The Right

The main goal of this research is to determine whether the journalism education of the leading media schools inGeorgia is adequate to modern media market’s demands and challenges. The right answer to this main questionwas found after analyzing Georgian media market’s demands, on the one hand, and, on the other hand, differentaspects of journalism education in Georgia: the historical background, development trends, evaluation ofeducational programs and curricula designs, reflection of international standards in teaching methods, studyingand working conditions.

Biochemical and Histopathological Evaluation of the Radioprotective Effects of Melatonin Against Gamma Ray-Induced Skin Damage

2019 ◽  
Vol 12 (1) ◽  
pp. 72-81 ◽  
Author(s):  
Dheyauldeen Shabeeb ◽  
Masoud Najafi ◽  
Ahmed Eleojo Musa ◽  
Mansoor Keshavarz ◽  
Alireza Shirazi ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Histopathological Examination ◽  
Radical Scavenging ◽  
Limiting Factor ◽  
Skin Damage ◽  
Exposed Skin ◽  
Male Wistar Rats ◽  
Time Periods ◽  
Skin Damages ◽  
The Right

Background:Radiotherapy is one of the treatment methods for cancers using ionizing radiations. About 70% of cancer patients undergo radiotherapy. Radiation effect on the skin is one of the main complications of radiotherapy and dose limiting factor. To ameliorate this complication, we used melatonin as a radioprotective agent due to its antioxidant and anti-inflammatory effects, free radical scavenging, improving overall survival after irradiation as well as minimizing the degree of DNA damage and frequency of chromosomal abrasions.Methods:Sixty male Wistar rats were randomly assigned to 4 groups: control (C), melatonin (M), radiation (R) and melatonin + radiation (MR). A single dose of 30 Gy gamma radiation was exposed to the right hind legs of the rats while 40 mg/ml of melatonin was administered 30 minutes before irradiation and 2 mg/ml once daily in the afternoon for one month till the date of rat’s sacrifice. Five rats from each group were sacrificed 4, 12 and 20 weeks after irradiation. Afterwards, their exposed skin tissues were examined histologically and biochemically.Results:In biochemical analysis, we found that malondialdehyde (MDA) levels significantly increased in R group and decreased significantly in M and MR groups after 4, 12, and 20 weeks, whereas catalase (CAT) and superoxide dismutase (SOD) activities decreased in the R group and increased in M and MR groups during the same time periods compared with the C group (p<0.05). Histopathological examination found there were statistically significant differences between R group compared with the C and M groups for the three different time periods (p<0.005, p<0.004 and p<0.004) respectively, while R group differed significantly with MR group (p<0.013). No significant differences were observed between C and M compared with MR group (p>0.05) at 4 and 20 weeks except for inflammation and hair follicle atrophy, while there were significant effects at 12 weeks (p<0.05).Conclusion:Melatonin can be successfully used for the prevention and treatment of radiation-induced skin injury. We recommend the use of melatonin in optimal and safe doses. These doses should be administered over a long period of time for effective radioprotection and amelioration of skin damages as well as improving the therapeutic ratio of radiotherapy.

The Taubman/Golandsky Approach to the Violin

Public Voices ◽  
2016 ◽  
Vol 12 (2) ◽  
pp. 7
Author(s):  
Sophie Till
Keyword(s):  
The Other ◽  
Technical Approach ◽  
Piano Technique ◽  
Pedagogical Approach ◽  
New Developments ◽  
Body Of Knowledge ◽  
Music Making ◽  
Helping Others ◽  
The One ◽  
The Right

Three years ago Sophie Till started working with pianist Edna Golandsky, the leading exponent of the Taubman Piano Technique, an internationally acclaimed approach that is well known to pianists, on the one hand, for allowing pianists to attain a phenomenal level of virtuosity and on the other, for solving very serious piano-related injuries. Till, a violinist, quickly realized that here was a unique technical approach that could not only identify and itemize the minute movements that underlie a virtuoso technique but could show how these movements interact and go into music making at the highest level. Furthermore, through the work of the Golandsky Institute, she saw a pedagogical approach that had been developed to a remarkable depth and level of clarity. It was an approach that had the power to communicate in a way she had never seen before, despite her own first class violin training from the earliest age. While the geography and “look” on the violin are different from the piano, the laws governing coordinate motion specifically in playing the instrument are the same for pianists and violinists. As a result of Till’s work translating the technique for violin, a new pedagogical approach for violinists of all ages is emerging; the Taubman/Golandsky Approach to the Violin. In reflecting on these new developments, Edna Golandsky wrote, “I have been working with the Taubman Approach for more than 30 years and have worked regularly with other instrumentalists. However, Sophie Till was the first violinist who asked me to teach her with the same depth that I do with pianists. With her conceptual and intellectual agility as well as complete dedication to helping others, she has been the perfect partner to translate this body of knowledge for violinists. Through this collaboration, Sophie is helping develop a new ‘language’ for violinist that will prevent future problems, solve present ones and start beginners on the right road to becoming the best they can be. The implications of this new work for violinists are enormous.”

Freedom of Expression versus Privacy and the Right to Reputation

2017 ◽  
Author(s):  
Dirk Voorhoof
Keyword(s):  
Public Interest ◽  
Freedom Of Expression ◽  
Media Freedom ◽  
Investigative Journalism ◽  
The Public ◽  
The Right Of Privacy ◽  
The One ◽  
Grand Chamber ◽  
The Right ◽  
The Impact

The normative perspective of this chapter is how to guarantee respect for the fundamental values of freedom of expression and journalistic reporting on matters of public interest in cases where a (public) person claims protection of his or her right to reputation. First it explains why there is an increasing number and expanding potential of conflicts between the right to freedom of expression and media freedom (Article 10 ECHR), on the one hand, and the right of privacy and the right to protection of reputation (Article 8 ECHR), on the other. In addressing and analysing the European Court’s balancing approach in this domain, the characteristics and the impact of the seminal 2012 Grand Chamber judgment in Axel Springer AG v. Germany (no. 1) are identified and explained. On the basis of the analysis of the Court’s subsequent jurisprudence in defamation cases it evaluates whether this case law preserves the public watchdog-function of media, investigative journalism and NGOs reporting on matters of public interest, but tarnishing the reputation of public figures.

scholarly journals MAPPING AND ENHANCING DESIGN STUDIES WITH PSI META-THEORETIC DESIGN FRAMEWORK

2021 ◽  
Vol 1 ◽  
pp. 2007-2016
Author(s):  
Yoram Reich ◽  
Eswaran Subrahmanian
Keyword(s):  
Design Research ◽  
The Other ◽  
Design Studies ◽  
Abstraction Level ◽  
Follow Up Studies ◽  
The One ◽  
The Right ◽  
Abstract Framework ◽  
Tools And Methods

AbstractDesign research as a field has been studied from diverse perspectives starting from product inception to their disposal. The product of these studies includes knowledge, tools, methods, processes, frameworks, approaches, and theories. The contexts of these studies are innumerable. The unit of these studies varies from individuals to organizations, using a variety of theoretical tools and methods that have fragmented the field, making it difficult to understand the map of this corpus of knowledge across this diversity.In this paper, we propose a model-based approach that on the one hand, does not delve into the details of the design object itself, but on the other hand, unifies the description of design problem at another abstraction level. The use of this abstract framework allows for describing and comparing underlying models of published design studies using the same language to place them in the right context in which design takes place and to enable to inter-relate them, to understand the wholes and the parts of design studies.Patterns of successful studies could be generated and used by researchers to improve the design of new studies, understand the outcome of existing studies, and plan follow-up studies.

Filippov solutions of vector Dirichlet problems

2020 ◽  
Vol 70 (2) ◽  
pp. 401-416
Author(s):  
Hana Machů
Keyword(s):  
Differential Equations ◽  
The State ◽  
State Variables ◽  
Dirichlet Problems ◽  
Filippov Solutions ◽  
Natural Notion ◽  
Growth Restrictions ◽  
The One ◽  
The Right ◽  
Effective Growth

Abstract If in the right-hand sides of given differential equations occur discontinuities in the state variables, then the natural notion of a solution is the one in the sense of Filippov. In our paper, we will consider this type of solutions for vector Dirichlet problems. The obtained theorems deal with the existence and localization of Filippov solutions, under effective growth restrictions. Two illustrative examples are supplied.

The State Policy towards the Homeless in Moldova between the ‘Left Hand’ and the ‘Right Hand’. The Case of Chișinău Shelter

Südosteuropa ◽  
2019 ◽  
Vol 67 (2) ◽  
pp. 175-195
Author(s):  
Petru Negură
Keyword(s):  
Homeless People ◽  
Severe Disabilities ◽  
The State ◽  
Small Scale ◽  
Left Hand ◽  
Right Hand ◽  
Binary Approach ◽  
The One ◽  
The Right ◽  
Depth Interviews

Abstract The Centre for the Homeless in Chișinău embodies on a small scale the recent evolution of state policies towards the homeless in Moldova (a post-Soviet state). This institution applies the binary approach of the state, namely the ‘left hand’ and the ‘right hand’, towards marginalised people. On the one hand, the institution provides accommodation, food, and primary social, legal assistance and medical care. On the other hand, the Shelter personnel impose a series of disciplinary constraints over the users. The Shelter also operates a differentiation of the users according to two categories: the ‘recoverable’ and those deemed ‘irrecoverable’ (persons with severe disabilities, people with addictions). The personnel representing the ‘left hand’ (or ‘soft-line’) regularly negotiate with the employees representing the ‘right hand’ (‘hard-line’) of the institution to promote a milder and a more humanistic approach towards the users. This article relies on multi-method research including descriptive statistical analysis with biographical records of 810 subjects, a thematic analysis of in-depth interviews with homeless people (N = 65), people at risk of homelessness (N = 5), professionals (N = 20) and one ethnography of the Shelter.

The Villa Item and a Bride's Ordeal

1929 ◽  
Vol 19 (1) ◽  
pp. 67-87 ◽  
Author(s):  
Jocelyn Toynbee
Keyword(s):  
The South ◽  
Important Paper ◽  
The North ◽  
Dwelling House ◽  
South Wall ◽  
The Subject ◽  
The One ◽  
The Individual ◽  
North Wall ◽  
The Right

The paintings in the triclinium of the Villa Item, a dwelling-house excavated in 1909 outside the Porta Ercolanese at Pompeii, have not only often been published and discussed by foreign scholars, but they have also formed the subject of an important paper in this Journal. The artistic qualities of the paintings have been ably set forth: it has been established beyond all doubt that the subject they depict is some form of Dionysiac initiation: and, of the detailed interpretations of the first seven of the individual scenes, those originally put forward by de Petra and accepted, modified or developed by Mrs. Tillyard appear, so far as they go, to be unquestionably on the right lines. A fresh study of the Villa Item frescoes would seem, however, to be justified by the fact that the majority of previous writers have confined their attention almost entirely to the first seven scenes—the three to the east of the entrance on the north wall (fig. 3), the three on the east wall and the one to the east of the window on the south wall, to which the last figure on the east wall, the winged figure with the whip, undoubtedly belongs.

Anesthesia-induced Suppression of Human Dorsal Anterior Insula Responsivity at Loss of Volitional Behavioral Response

2016 ◽  
Vol 124 (4) ◽  
pp. 766-778 ◽  
Author(s):  
Catherine Elizabeth Warnaby ◽  
Marta Seretny ◽  
Roísín Ní Mhuircheartaigh ◽  
Richard Rogers ◽  
Saad Jbabdi ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Anterior Insula ◽  
Cortical Region ◽  
Dorsolateral Prefrontal ◽  
Behavioral Responsiveness ◽  
Insula Cortex ◽  
Evoked Activity ◽  
The Right ◽  
Conjunction Analysis ◽  
External Stimuli

Abstract Background It has been postulated that a small cortical region could be responsible for the loss of behavioral responsiveness (LOBR) during general anesthesia. The authors hypothesize that any brain region demonstrating reduced activation to multisensory external stimuli around LOBR represents a key cortical gate underlying this transition. Furthermore, the authors hypothesize that this localized suppression is associated with breakdown in frontoparietal communication. Methods During both simultaneous electroencephalography and functional magnetic resonance imaging (FMRI) and electroencephalography data acquisition, 15 healthy volunteers experienced an ultraslow induction with propofol anesthesia while a paradigm of multisensory stimulation (i.e., auditory tones, words, and noxious pain stimuli) was presented. The authors performed separate analyses to identify changes in (1) stimulus-evoked activity, (2) functional connectivity, and (3) frontoparietal synchrony associated with LOBR. Results By using an FMRI conjunction analysis, the authors demonstrated that stimulus-evoked activity was suppressed in the right dorsal anterior insula cortex (dAIC) to all sensory modalities around LOBR. Furthermore, the authors found that the dAIC had reduced functional connectivity with the frontoparietal regions, specifically the dorsolateral prefrontal cortex and inferior parietal lobule, after LOBR. Finally, reductions in the electroencephalography power synchrony between electrodes located in these frontoparietal regions were observed in the same subjects after LOBR. Conclusions The authors conclude that the dAIC is a potential cortical gate responsible for LOBR. Suppression of dAIC activity around LOBR was associated with disruption in the frontoparietal networks that was measurable using both electroencephalography synchrony and FMRI connectivity analyses.

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