1,301 research outputs found
A Muslim Perspective of Leadership – Insights from Oman
This paper presents a Muslim perspective of leadership as viewed from observing leaders in Muscat, Oman – the capital city of the Middle East country that has grown at the rate of just under 4% per year since 2000 and is awash with residents from places throughout the world. With this rate of growth and rich diversity, leadership designed to make an equitable impact is required to govern
Onset of Floquet Thermalisation
In presence of interactions, a closed, homogeneous (disorder-free) many-body
system is believed to generically heat up to an `infinite temperature' ensemble
when subjected to a periodic drive: in the spirit of the ergodicity hypothesis
underpinning statistical mechanics, this happens as no energy or other
conservation law prevents this. Here we present an interacting Ising chain
driven by a field of time-dependent strength, where such heating onsets only
below a threshold value of the drive amplitude, above which the system exhibits
non-ergodic behaviour. The onset appears at {\it strong, but not fast} driving.
This in particular puts it beyond the scope of high-frequency expansions. The
onset location shifts, but it is robustly present, across wide variations of
the model Hamiltonian such as driving frequency and protocol, as well as the
initial state. The portion of nonergodic states in the Floquet spectrum, while
thermodynamically subdominant, has a finite entropy. We find that the
magnetisation as an {\it emergent} conserved quantity underpinning the
freezing; indeed the freezing effect is readily observed, as initially
magnetised states remain partially frozen {\it up to infinite time}. This
result, which bears a family resemblance to the Kolmogorov-Arnold-Moser theorem
for classical dynamical systems, could be a valuable ingredient for extending
Floquet engineering to the interacting realm.Comment: 10 pages, including Supplemental Materia
Investigating and extending the methods in automated opinion analysis through improvements in phrase based analysis
Opinion analysis is an area of research which deals with the computational treatment of opinion statement and subjectivity in textual data. Opinion analysis has emerged over the past couple of decades as an active area of research, as it provides solutions to the issues raised by information overload. The problem of information overload has emerged with the advancements in communication technologies which gave rise to an exponential growth in user generated subjective data available online. Opinion analysis has a rich set of applications which are used to enable opportunities for organisations such as tracking user opinions about products, social issues in communities through to engagement in political participation etc.The opinion analysis area shows hyperactivity in recent years and research at different levels of granularity has, and is being undertaken. However it is observed that there are limitations in the state-of-the-art, especially as dealing with the level of granularities on their own does not solve current research issues. Therefore a novel sentence level opinion analysis approach utilising clause and phrase level analysis is proposed. This approach uses linguistic and syntactic analysis of sentences to understand the interdependence of words within sentences, and further uses rule based analysis for phrase level analysis to calculate the opinion at each hierarchical structure of a sentence. The proposed opinion analysis approach requires lexical and contextual resources for implementation. In the context of this Thesis the approach is further presented as part of an extended unifying framework for opinion analysis resulting in the design and construction of a novel corpus. The above contributions to the field (approach, framework and corpus) are evaluated within the Thesis and are found to make improvements on existing limitations in the field, particularly with regards to opinion analysis automation. Further work is required in integrating a mechanism for greater word sense disambiguation and in lexical resource development
DNA Sequence Representation by Use of Statistical Finite Automata
This project defines and intends to solve the problem of representing information carried by DNA sequences in terms of amino acids, through application of the theory of finite automata. Sequences can be compared against each other to find existing patterns, if any, which may include important genetic information. Comparison can state whether the DNA sequences belong to the same, related or entirely different species in the ‘Tree of Life’ (phylogeny). This is achieved by using extended and statistical finite automata. In order to solve this problem, the concepts of automata and their extension, i.e. Alergia algorithm have been used. In this specific case, we have used the chemical property - polarity of amino acids to analyze the DNA sequences
INFILTRATION KINETICS STUDY AND PROCESSING OF LAYERED GRADED Al2O3-ZrO2 COMPOSITE
INFILTRATION KINETICS STUDY AND PROCESSING OF LAYERED GRADED Al2O3-ZrO2 COMPOSITE. Layered graded Al2O3-ZrO2 composite was successfully synthesised through infiltration of porous Al2O3 preform with a solution containing ZrOCl2.8H2O. The infiltration rate of liquid into porous Al2O3 preformhad also been investigated. It was found that the infiltration rate equation proposed by Washburn is most suitable for describing the effects of preform sintering temperature, viscosity and multiple infiltrations on the infiltration behaviour, whereas the influence of applied pressure is consistent with the model proposed by Darcy, where the applied pressure enhances the infiltration rate behaviour. Depth profilling of layered graded Al2O3-ZrO2 composite was characterised by x-ray diffraction, the result shows that the concentration of ZrO2 decreased with depth, while that of Al2O3 increased with depth
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Response of the Indonesian Seas and its potential feedback to the Madden Julian Oscillation
The impact of the Madden Julian Oscillation (MJO), a major source of intraseasonal variability in the tropical atmosphere, on the Indonesia Seas is investigated using satellite-derived, reanalysis and mooring data. The MJO footprint on the Indonesian Seas is evident from the surface layer into the pycnocline. In the surface, MJO air-sea heat fluxes govern the intraseasonal sea surface temperature (SST) variations. Within the pycnocline, the MJO reduces the transfer of the Pacific water to the Indian Ocean, the Indonesian Throughflow (ITF). In addition to the ocean’s response, the oceanic feedback to the MJO is also examined. Warmer SST in the Indonesian Seas during the suppressed phase of the MJO promotes the MJO convective phase to propagate eastward over the maritime continent (MC).
Intraseasonal SST variation accounts for 55 - 60% of the total non-seasonal SST variance across the Indonesian Seas. It is most energetic in Banda and Timor Seas, with its standard deviation varying between 0.4 – 0.5°C. Coupled to the MJO surface fluxes, the intraseasonal SST exhibits stronger variation in boreal winter than in summer. A slab ocean model indicates that MJO surface heat fluxes account for 69-78% of the intraseasonal SST variability. The SST increases by 1.1° - 2°C, on average, in response to intense surface heating and weak winds over the suppressed (dry) MJO phase, and then decreases by 1.8° - 2.1°C over the course of the ensuing MJO active phase that is characterized by enhanced convective cooling and westerly wind bursts. Intraseasonal variability is also significant in the Sulawesi Sea SST, but it is mostly derived from eddies and local winds.
Over the period 1980 - 2012, we observe 86 significant MJO (Real-time Multi variate MJO index > 1) events occurring in the Indian Ocean, of which 51 events achieve eastward propagation (EP) over the MC, while 35 events attentuate in the eastern Indian Ocean, or show no propagation (NP) over the MC. Eastward propagation (EP) MJO events occur more frequently during La Niña years than during El Niño years. Analyses of SST across the Indonesian Seas during the suppressed phase of the MJO events indicate that the SST in Java, Banda, and Timor Seas attributed to the EP MJO events is warmer by 0.5oC that associated with the NP MJO events. The warmer SST corresponds with enhanced surface latent heat flux, sensible heat flux, and low-level moisture in the atmospheric boundary layer, driven by diurnal activity. The EP MJO events are more frequent during La Niña, as the SST response to MJO events is influenced by the thermocline depth: shallower thermocline during El Niño enables cooler subsurface water under the MJO forcing to reduce SST that then attenuates MJO activity, with deeper thermocline of La Niña having the opposite outcome.
Moored velocity data in Makassar Strait between 2004 – August 2011 and August 2013 – August 2015 document substantial direct impacts of the MJO on the ITF, particularly with the surface layer (< 80 m ). A composite of the along-strait velocity within the surface layer for 10 MJO events observed during the observational period exhibits strong northward velocity within days, following the peak of MJO wind stress. The MJO forces both northward along-strait pressure gradient and the resultant of northward wind stress and turbulent stress at the base of the surface layer that, together with the seasonal forcing, maintain the reduction or even reversal of the ITF southward transport on timescales of 1-3 months during boreal winter
Current Trends in the Management of Endodontic Emergencies
Introduction: The management of endodontic emergencies has changed over the last few decades and varies from practice to practice. This is due to the development of new materials, new irrigation techniques, and new evidence-based research which supports clinical success. An updated questionnaire is necessary to further advance the clinical knowledge in endodontic emergencies based on current practices. Therefore, the purpose of this research is to determine the difference practice modalities between members who are board certified, who are not board certified, and endodontic graduate residents.
Materials and Methods: In 2021, every member of the American Association of Endodontics (n = 3157) were asked to complete a short survey about clinical practices and 394 (12.5%) completed the survey. The survey included questions regarding length of time between emergency treatment and definitive treatment, routinely prescribed antibiotics and analgesics, cone beam computed tomography use, level of pulp removal and instrumentation, and treatment modalities for teeth that exhibit swelling and drainage. The collected data were then statistically analyzed.
Results: The overall preference in recommended analgesia was ibuprofen with 99.2% of all participants indicating that choice. The second most recommended analgesia was acetaminophen. It was recommended by 66.4% of all participants. The most recommended antibiotic was amoxicillin followed by clindamycin. Participants at all levels of education had similar choices in supplemental anesthesia. Board certified endodontists were more likely than non-board certified endodontists or residents to use a CBCT during endodontic emergencies (p \u3c 0.05). Considering microscope use, board certified endodontists were more likely than non-board certified endodontists or residents to always use a microscope (p \u3c 0.05). Most participants choice to wait 1-2 weeks from initiating treatment to completing treatment, an evidence-based recommendation. Majority of participants instrument to apex using the electronic apex locator, and completed the instrumentation in all 7 diagnoses. Among adjunct treatment, incision and drainage on average was selected over leave tooth open, insert drain, and artifistulation.
Conclusion: Overall, residents and non-board certified endodontists treat patients similarly. The major differences are in CBCT use and microscope. Majority of participants instrument to the electronic apex locator reading and complete instrumentation. One major concern is the use of clindamycin which is no evidence based any longer and requires greater continued education on its prescription use in patients
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