111 research outputs found
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The dynamics and determinants of Kuwait's long-run economic growth
This paper develops a quarterly macro-econometric model for the Kuwaiti economy estimated over the period 1979Q2-2013Q1, allowing us to investigate the long-run role of oil income in the development of Kuwait as well as the direct effects of oil revenue, foreign output, and equity price shocks on real output. More specifically, we examine to what extent Kuwaiti real output in the long run is shaped by oil revenue through their impact on capital accumulation, and technological transfers through foreign output. Using the same modelling strategy we also explore the role of oil income in terms of long-run private and public sector output growth (separately). The estimates suggest that real domestic output in the long run is influenced by oil revenues and foreign output (a proxy for technological progress), and technological growth in Kuwait is on a par with the rest of the world. Furthermore, while we show that both oil revenues and foreign output drive growth in the public sector, it seems that technological progress is the main (and only) driver for private sector real growth. Finally, our results show that oil revenue and global equity market shocks have a large and significant long-run impact on Kuwait's real output and public sector GDP. In comparison, the effects of the foreign output shock is muted
Isotopic-mass dependence of the A, B, and C excitonic band gaps in ZnO at low temperatures
Low temperature wavelength-modulated reflectivity measurements of isotopically engineered ZnO samples have yielded the dependence of their A, B, and C excitonic band gaps on the isotopic masses of Zn and O. The observed dependence is analyzed in terms of the band gap renormalization by zero-point vibrations via electron-phonon interaction and the volume dependence on isotopic mass. A simplified, two-oscillator model, employed in the analysis, yields zero-point renormalizations of the band gaps, -154 +/- 14 meV (A), -145 +/- 12 meV (B), and -169 +/- 14 meV (C), for ZnO with natural isotopic composition
Electron-phonon renormalization of electronic band gaps of semiconductors: Isotopically enriched silicon
Photoluminescence and wavelength-modulated transmission spectra displaying phonon-assisted indirect excitonic transitions in isotopically enriched Si-28, Si-29, Si-30, as well as in natural Si, have yielded the isotopic mass (M) dependence of the indirect excitonic gap (E-gx) and the relevant phonon frequencies. Interpreting these measurements on the basis of a phenomenological theory for (partial derivativeE(gx)/partial derivativeM), we deduce E-gx(M=infinity)=(1213.8+/-1.2) meV, the purely electronic value in the absence of electron-phonon interaction and volume changes associated with anharmonicity
Laparoscopic anterior gastropexy for chronic recurrent gastric volvulus: a case report
<p>Abstract</p> <p>Introduction</p> <p>Gastric volvulus is an uncommon clinical entity, first described by Berti in 1866. It is a rotation of all or part of the stomach through more than 180°. This rotation can occur on the longitudinal (organo-axial) or transverse (mesentero-axial) axis. This condition can lead to a closed-loop obstruction or strangulation. Traditional surgical therapy for gastric volvulus is based on an open approach. Here we report the case of a patient with chronic intermittent gastric volvulus who underwent a successful laparoscopic treatment.</p> <p>Case presentation</p> <p>A 34-year-old woman presented with multiple episodes of recurrent upper abdominal pain associated with retching and vomiting, treated unsuccessfully with intramuscular metoclopramide. Endoscopic examination of the upper digestive tract showed a suspected rotation of the stomach, and a chronic recurrent gastric volvulus was revealed by barium meal. The patient was operated on successfully, with an anterior laparoscopic gastropexy performed as the first surgical approach.</p> <p>Conclusion</p> <p>Experience with laparoscopic anterior gastropexy is limited only to a few described cases. Our patient was clinically and radiologically followed-up for 2 years with no evidence of recurrence, either radiological or symptomatic. Based on this result, laparoscopic gastropexy can be seen and considered as an initial 'gold standard' for the treatment of gastric volvulus.</p
HCI policy and the smart city
While the idea of the âSmart Cityâ has attracted increasing attention from academia, industry, and government this interest has largely had a technical and technological focus. This paper identifies some of the important political and policy challenges facing the idea, the discourse, of a âsmart cityâ as a means to optimise HCI input into the âsmart cityâ debate. It then addresses that gap by detailing a research project that explored how experts in smart city research and development in the UK context responded to this policy challenge. Experts were asked questions regarding their prior experience with the âsmart cityâ, their understandings of what it means for a city to be smart, and what policy potentials they've recognised in the smart city. The paper analyses and offers a synthesis of the responses collected throughout the research with the current policies concerning various smart city proximity, thereby providing a critical assessment of the values underlying the smart city. The paper aims to explore and present some of the policy possibilities for UK smart cities that are potentially useful for politicians, policy makers, planners, academics, and technology companies. I believe that these perspectives for policy development can be used to inform responsible development, spatially and socially inclusive technologies, and ultimately more resilient and liveable cities
Evaluating hospital websites in Kuwait to improve consumer engagement and access to health information:a cross-sectional analytical study
Abstract Background Current advances in information and communication technology have made accessing and obtaining health-related information easier than ever before. Today, many hospital websites use a patient-centric approach to promote engagement and encourage learning for better health-related decision making. However, little is known about the current state of hospital websites in the State of Kuwait. This study aims to evaluate hospital websites in Kuwait and offer recommendations to improve patient engagement and access to health information. Methods This study employs a cross-sectional analytical approach to evaluate hospital websites in Kuwait in 2017. The websites of hospitals that provide in-patient services were identified through a structured search. Only active websites that were available in either English or Arabic were considered. The evaluation of the websites involved a combination of automated and expert- based evaluation methods and was performed across four dimensions: Accessibility, Usability, Presence, and Content. Results Nine hospitals met the inclusion criteria. Most of the websites fell short in all four dimensions. None of the websites passed the accessibility guidelines. The usability of websites varied between hospitals. Overall, the majority of hospitals in Kuwait have rudimentary online presence and their websites require careful reassessment with respect to design, content, and user experience. The websites focus primarily on promoting services provided by the hospital rather than engaging and communicating with patients or providing evidence-based information. Conclusions Healthcare organization and website developers should follow best-practices to improve their websites taking into consideration the quality, readability, objectivity, coverage and currency of the information as well as the design of their websites. Hospitals should leverage social media to gain outreach and better engagement with consumers. The websites should be offered in additional languages commonly spoken by people living in Kuwait. Efforts should be made to ensure that health information on hospital websites are evidence-based and checked by healthcare professionals
The Weyl double copy from twistor space
The Weyl double copy is a procedure for relating exact solutions in biadjoint scalar, gauge and gravity theories, and relates fields in spacetime directly. Where this procedure comes from, and how general it is, have until recently remained mysterious. In this paper, we show how the current form and scope of the Weyl double copy can be derived from a certain procedure in twistor space. The new formalism shows that the Weyl double copy is more general than previously thought, applying in particular to gravity solutions with arbitrary Petrov types. We comment on how to obtain anti-self-dual as well as self-dual fields, and clarify some conceptual issues in the twistor approach
Empirical investigation to explore potential gains from the amalgamation of Phase Changing Materials (PCMs) and wood shavings
The reduction of gained heat, heat peak shifting and the mitigation of air temperature fluctuations are some desirable properties that are sought after in any thermal insulation system. It cannot be overstated that these factors, in addition to others, govern the performance of such systems thus their effect on indoor ambient conditions. The effect of such systems extends also to Heating, Ventilation and Air-conditioning (HVAC) systems that are set up to operate optimally in certain conditions. Where literature shows that PCMs and natural materials such as wood-shavings can provide efficient passive insulation for buildings, it is evident that such approaches utilise methods that are of a degree of intricacy which requires specialist knowledge and complex techniques, such as micro-encapsulation for instance. With technical and economic aspects in mind, an amalgam of PCM and wood-shavings has been created for the purpose of being utilised as a feasible thermal insulation. The amalgamation was performed in the simplest of methods, through submerging the wood shavings in PCM. An experimental procedure was devised to test the thermal performance of the amalgam and compare this to the performance of the same un-amalgamated materials. Comparative analysis revealed that no significant thermal gains would be expected from such amalgamation. However, significant reduction in the total weight of the insulation system would be achieved that, in this case, shown to be up to 20.94%. Thus, further reducing possible strains on structural elements due to the application of insulation on buildings. This can be especially beneficial in vernacular architectural approaches where considerably large amounts and thicknesses of insulations are used. In addition, cost reduction could be attained as wood shavings are significantly cheaper compared to the cost of PCMs
Topology and Wilson lines: global aspects of the double copy
The Kerr-Schild double copy relates exact solutions of gauge and gravity
theories. In all previous examples, the gravity solution is associated with an
abelian-like gauge theory object, which linearises the Yang-Mills equations.
This appears to be at odds with the double copy for scattering amplitudes, in
which the non-abelian nature of the gauge theory plays a crucial role.
Furthermore, it is not yet clear whether or not global properties of classical
fields - such as non-trivial topology - can be matched between gauge and
gravity theories. In this paper, we clarify these issues by explicitly
demonstrating how magnetic monopoles associated with arbitrary gauge groups can
be double copied to the same solution (the pure NUT metric) in gravity. We
further describe how to match up topological information on both sides of the
double copy correspondence, independently of the nature of the gauge group.
This information is neatly expressed in terms of Wilson line operators, and we
argue through specific examples that they provide a useful bridge between the
classical double copy and the BCJ double copy for scattering amplitudes.Comment: 31 pages, 4 figures. Some minor corrections have been implemente
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