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- الأعداد السابقة
- الأعداد السابقة
QScience Connect - الأعداد السابقة
المجلد 2014, العدد 1
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Evaluation of a posterior cruciate ligament deficient human knee joint finite element model
المؤلفون: Achilles Vairis, Markos Petousis, Nectarios Vidakis, Betina Kandyla and Andreas-Marios TsainisThe human knee joint has a three-dimensional geometry with multiple body articulations that produce complex mechanical responses under loads that occur in everyday life and sports activities. Knowledge of the complex mechanical interactions of these load-bearing structures is of use when treatments of relevant diseases are evaluated and assisting devices are designed. Numerical tools, such as the finite element analysis, are suitable for such modeling and can be used with success by students as well as experienced researchers alike. These tools have been used to develop an accurate human knee joint model to study its mechanical behavior.
This model has been used to study the kinematics of a PCL deficient human knee joint. Both linear and non-linear material models were developed for comparison purposes.
The main objective of this study is to verify developed knee joint models. Displacement results for static load cases presented in previous modeling work were used. Results were in agreement with those of the study employed for validation.
Results were compared with work from previous authors' studies, for the intact and the ACL deficient human knee joint. This aimed to understand the behavior of the knee joint and to verify that the model produced results in agreement with real life knee joint behavior with these types of injuries, as described in literature.
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Sustainable development in Qatar: Challenges and opportunities
المؤلفون: Renee A. RicherThis work outlines the issue of sustainable development in a global context as well as examining the potential for success, in terms of development strategy, in Qatar. The aim of the paper is threefold: Define sustainable development and what pursuing a path of “sustainable development” means for Qatar. Outline the challenges facing Qatar in terms of realizing the vision of sustainable development; and explore currently unrealized opportunities for sustainable development.
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Dynamics of innovation in Qatar and its transition to knowledge-based economy: Relative strengths and weaknesses
المؤلفون: Nezameddin Faghih and Leyla SarfarazQatar, as the most competitive economy in the region, seeks the transition to a knowledge-based economy. Innovation plays a crucial role in the economic development transform stage (from a resource-based to a knowledge-based economy) promising a more sustainable future. Hence, this paper presents a descriptive study of the status quo of Qatar in innovation and considers its domestic innovation dynamics through the Global Innovation Measure (Index) data, while also comparing Qatar to Switzerland as the world leading economy with a full Innovation Efficiency Ratio (100%) in the Global Innovation Index. Moreover, in order to enable further progress in Qatar's innovation level, the relative strengths and weaknesses of its innovation elements should be identified and explored. Subsequently, some of Qatar's innovation dynamics are studied over time, in order to provide not only useful feedback, but to propose guidelines for the authorities in the process of decision-making. Extensive future research and analytical studies required for full exploration and identification of Qatar's innovation dynamics are recommended in order to provide comprehensive and detailed guidelines for the decision-making authorities. The results obtained in this research indicate that Qatar has shown a promising start towards economic development in recent years and that Qatar's scores are excellent in some areas: political stability, ease of paying taxes, tertiary inbound mobility, general infrastructure, electricity output, electricity consumption, intensity of domestic competition, research collaborations between university and industry, innovation linkages, cluster development state, joint venture and strategic alliance deals, growth rate of GDP per person engaged, intangible assets, information and communication technologies, and organizational and business model creation. Its scores are also satisfactory in many other areas. Nevertheless, there are indicators that require improvements and amplifications, such as: expenditure on education, assessment in reading, mathematics, science, employment in knowledge-intensive services, knowledge absorption, foreign direct investment, net inflows, scientific and technical publications, total computer software spending, knowledge diffusion, high-tech exports, communications, computer and information services imports and exports, creative goods services and exports.
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Molecular Monitoring of patients with Chronic Myeloid Leukemia (CML) in the state of Qatar: Optimization of Techniques and Response to Imatinib
Most cases of chronic myeloid leukemia (CML) are associated with the presence of BCR-ABL1 fusion gene; a molecular anomaly that introduced targeting therapy to CML. This study was setup primarily to optimize the real-time quantification detection of BCR-ABL1 transcripts, in order to pave the way for using this method as a diagnostic tool to support the clinical management of CML patients in Qatar.
A secondary objective was to evaluate the response of CML patients to Imatinib (IM) and exploit adaption of this technique as an indicator of emerging drug resistance reported in Qatar.
Peripheral blood (PB) samples from 26 CML patients receiving Imatinib, were analysed via serial Real-time quantitative polymerase chain reaction (RT-qPCR) to monitor the ratio of BCR-ABL1 to normal ABL1 transcripts. EuropeanLeukemia Net (ELN) 2006 and 2009 guidelines were employed to assess the molecular response to Imatinib.
For patients to be classified as optimal responders, major molecular response (MMR) had to be achieved by 18 months of treatment.1 Patients responding to Imatinib achieved major molecular response (MMR) during the 1st year of treatment; while patients who resisted Imatinib treatment did not achieve any molecular response within this time frame.
This was the first molecular study to evaluate the molecular response of CML patients (citizens and residents) to IM in Qatar.
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Determinantal and permanental representation of q-Fibonacci polynomials
المؤلفون: İnci Gültekin and Yasemin TaşyurduIn this study, we show determinants and permanents of some Hessenberg matrices that give terms of polynomials .
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Assessment of infrastructural determinants for quality improvement programs for healthcare organizations in Qatar
المؤلفون: Khawla A. AthamnehThe purpose of this descriptive, comparative study was to re-examine certain organizational and structural elements that correlate with the effectiveness of quality improvement program implementation in hospitals. These elements are: (a) leadership commitment and support for quality improvement, (b) process understanding and integration with quality improvement, (c) human resource and training, (d) planning short and long-term quality plans, (e) information and data management, (f) customer focus, (g) innovation-oriented culture, and (h) a supplier partnership, built on trust and the exchange of information.
The study was conducted in five hospitals in Hamad Medical Corporation (HMC) in the State of Qatar. A validated questionnaire was used and purposely surveyed 221 employees. To ensure the generality of data, the results were compared to results of a similar study conducted in the same setting in 2009.
The findings identified a significant relationship between the specified infrastructural elements and the implementation of quality programs at the organizational level. The study conclusion determines factors facilitating the implementation of effective quality program in healthcare organizations.
Building on the study conclusions; an operational model for effective implementation of quality improvement programs in healthcare organizations was constructed. The model provides an evidence-based framework for hospitals' leaders; they will be able to take into consideration the factors that contribute to the success of the implementation of quality improvement programs, from as early as the planning stages.
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Sports Entrepreneurship: A dynamic model of the fundamental economic factors in the English Premier League
المؤلفون: Nezameddin Faghih and Ehsan JavanmardiEconomic factors undoubtedly play an important role in sports entrepreneurship, especially football, and fans' support helps clubs to increase their revenue and improve their financial status. The aim of this study is to systematically investigate spectator demand in the English Premier League, its interaction with the media and the effects of these variables on club revenue. Questions raised in this study deal with, as far as the variable of spectator demand is concerned, whether or not the system is in a steady state after going through a transition period. This paper studies the relationship between media attention, spectator demand and club revenue, as far as system dynamics is concerned. How the system behaves in the long run and the behavior of each system variable in the future, are other key issues of interest in this paper.
Methodology is based on system dynamics modeling. The model developed is based on data collected from the English Premier League from 1995 to 2010. The state of the system and its stability are investigated through analysis of variance and Chow test.
This study shows during a transition period, the system goes through normal stages and reaches a stable, steady state, and the system's future behavior will remain consistent; the variables of media attention, spectator demand and club revenue follow an exponential long-term trend. The application of a system dynamics approach is useful not only in exploring, revealing and understanding such significant features, but also in paving the way for subsequent studies to consider more variables introduced into model, simulating the system in a larger scope. This would allow systemic investigation of more parameters, including those affecting demand (e.g., social factors or appeal), and consequently studying system behaviors in a larger dimension. Based on the system dynamics approach presented in this paper, a multi input – multi output state space modeling of the system can be approached, in order to enable transfer function derivations, finding unstable poles in the stability analysis, stabilizing the instabilities, and system optimization. Nonetheless, nonlinear modes and behaviors of the system can also be explored for thorough system identification.
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