"Tonight My Gun Is Loaded": Poetic Dueling In Arabia

Although folk traditions are rapidly disappearing in Arabia as it is suddenly transformed from an illiterate society to a modern state, poetic dueling remains one of the most popular and spectacular folk performances. Oral poets are paid handsomely at weddings, festivals, and similar public occasions to entertain spectators with their verbal jousts. Encouraged by eager audiences and by an accompanying chorus that repeats their improvised verses, the competing poets can stay up singing and playing until the call to the morning prayer.--Introduction

Conversion Of Dimethyl-Ether to Olefins Over HZSM-5: Reactivity and Kinetic Modeling

Light olefins are key intermediates in the petrochemical industry. Nowadays, finding economic alternative routes for light olefin synthesis is among the main goals for many petrochemical companies. The conversion of natural gas to light olefins is one of the promising routes in which DME is an intermediate that can be synthesized directly from syngas. This route requires having DME as a feedstock to produce light olefins (DTO) using an HZSM-5 catalyst. In this catalytic process, the DME converts first to light olefins that may further transformed, forming heavier C4+ hydrocarbons. Thus, selecting a proper catalyst and suitable operating conditions that may lead to minimize olefins further conversion is a key for the implementation of the DTO process. In order to accomplish this, kinetic modeling and catalyst design is very critical. To our knowledge, there is no study cited in the technical literature addressing these topics jointly and this is the case, despite their great significance for DTO reactor scale-up. Given the originality and the economic incentive of the above subject, the aim of the present research is to investigate HZSM-5 as a potential selective and robust catalyst for light olefin production from DME. The detailed objectives of this PhD dissertation include catalyst preparation, characterization, testing under reaction conditions and kinetic modeling. The catalyst characterization addresses the influence of the SiO2/Al2O3 ratio (30, 80, and 280) on HZSM-5 physicochemical properties. The reactivity runs, on the hand, are intended to achieve the maximum catalyst performance and light olefin selectivity by varying the SiO2/Al2O3 ratio in the HZSM-5 catalyst. The kinetic study involves a reaction scheme and the development of a model suitable to describe the reaction network. The proposed kinetic model includes establishing the rates for the individual steps, assembling the individual chemical species balances, and using the experimental data to determine numerically the phenomenologically based kinetic parameters. Regarding the catalyst characterization in the present PhD dissertation, N2 isotherm data show a dual hysteresis loop for HZSM-5 with a SiO2/Al2O3 = 280 ratio compared to a single hysteresis loop produced by HZSM-5 with a lower SiO2/Al2O3 ratio. The NLDFT cylindrical model confirmed the HZSM-5 characteristic 5.5 Ǻ pore size. On the basis of the XRD and N2-isotherm results, the SiO2/Al2O3 ratio appears not to have an effect on HZSM-5 structural properties. NH3-TPD and Pyridine-FTIR confirmed that in HZSM-5, weak acidity encompasses Lewis and hydrogen-bonded sites. The strong acidity mainly involves the Brönsted acid sites with a ratio of weak to strong acid sites and a total acidity being reduced with the SiO2/Al2O3 ratio. Furthermore, NH3 desorption kinetics allows the calculation of activation energies and rate constants for both strong and weak acid sites. This allows one to show that desorption rate constants vary with the changes in weak and strong acid sites as observed with NH3-TPD and Pyridine-FTIR. Concerning catalyst reactivity and more specifically DME conversions and catalyst deactivation, it is proven in the present study, that both augment with the acidity of the HZSM-5 (SiO2/Al2O3 in the 30-80 range) and the reaction temperature. The HZSM-5 catalyst with a SiO2/Al2O3 = 280 ratio, however, provides a stable operation with higher light olefin selectivity (ethylene, propene and butene). As a result, this catalyst was chosen in the present PhD dissertation, for the development of the DTO reaction network. In this respect, for this catalyst, light olefins were found to be the major products at low conversion (2%) with minor heavy olefins and with no paraffins or aromatics produced. With the raising of the DME conversion up to 45%, C5+ olefins, paraffins, and aromatics selectivities were more abundant, increasing consistently at the expense of the light olefins. In addition, at DME conversions higher than 45%, the change of the product selectivities became less pronounced. At the maximum DME conversion of 74%, the attained selectivites for light olefins, heavy olefins, paraffins, and aromatics were 48%, 32%, 9%, and 11%, respectively. The reaction elementary steps were modeled using carbenium ion chemistry. In the DTO reaction network, surface bound methoxy species play a vital role as methylating agents for both olefins and aromatics. Furthermore, the resulting kinetic model for DTO was established using rigorous statistical analysis. This was done estimating DTO hydrocarbon species reaction rate parameters using non-linear regression and experimental data. It was observed that the pre-exponential factors for methylating olefins and aromatics decreased consistently with the increase of the carbon number of the species being methylated. The activation energy for methylating light olefins was found to be slightly higher (169 kJ/mol) when compared to that for the heavy olefins (156 kJ/mol). On the other hand, the aromatic methylation reaction, displayed a higher activation energy as the number of methyl groups in the aromatic ring increased (104 -191 kJ/mol)

Internet Adoption in Gulf Cooperation Council’s Tourism Industry

The purpose of this paper is to explore the use of internet applications and their effects in the tourism industry of the Gulf Cooperation Council (GCC). As a platform for e-commerce, the internet remains a reliable tool for use in the tourism industry, a conception that continues to win increased acceptance among major players in the industry. Despite evidence of slow rates of internet adoption in the tourism sectors of some nations, the future of tourism seems heavily dependent on this technology. This exploration is conducted based on available theoretical models which have been used on the subject in other countries, with the findings forming the basis in asserting the future of the tourism industry in the GCC.  Conservativeness was found to be a major setback to the sustained competitive exploitation of internet value in GCC’s tourism industry. Key Words: e-commerce, internet, GCC, touris

The effect of therapy on arousal from sleep in patients with respiratory sleep disorders

Vibrotactile positional therapy (PT) is a relatively new treatment for positional obstructive sleep apnoea (POSA). It uses vibrotactile stimulus to encourage the sleeper to change position when supine. The overall aim of this thesis was to investigate the efficacy of vibrotactile PT as a clinical treatment for patients with POSA. To achieve this, different experimental approaches were used, including a systematic review and meta-analysis, a clinical trial, and a physiological study. The systematic review was carried out to evaluate the effect of vibrotactile PT on apnoea hypopnoea index (AHI), percentage of time spent in supine (%Tsupine), and patient-centred outcomes in patients with POSA compared to baseline. The results showed that vibrotactile PT was effective in reducing both AHI and %Tsupine. Although the Epworth Sleepiness Scale and the Functional Outcomes of Sleep Questionnaire minimally improved, these changes did not reach clinically important differences; however, limited data were found on quality of life (SF-36) vitality score. A prospective, three-month, multicentre, randomised, parallel, double-blind trial (The POSA Trial, ISRCTN51740863) was developed to investigate the effect of vibrotactile PT on AHI, quality of life and daytime functioning at follow-up, adjusted for the baseline, in patients with POSA compared to sham-vibrotactile PT. Baseline data (AHI, quality of life and daytime functioning) obtained from the participants recruited at the Royal Brompton Hospital are presented in the thesis. The mean baseline AHI for RBH participants was in the mild OSA category compared to the patients in the systematic review; however, a higher baseline %Tsupine was found. The baseline patient-centred outcomes were also comparable to those found in the systematic review. A physiological study in healthy participants (n=27) was carried out to investigate the effect of vibrotactile stimulus on arousability from sleep. A novel analysis method was developed to measure arousability. This included the duration from the vibrotactile stimulus to the position change using polysomnography. The results of this study showed heterogenous arousability responses to the vibrotactile stimulus with different phenotypes. Compared to males, healthy females took longer to respond to the vibrotactile stimulus and, therefore, were more resilient to arousability. In summary, the findings of this thesis have shown that vibrotactile PT devices are effective in treating patients with POSA. However, limited data on sensitive patient-centred outcomes exist. The POSA trial will provide data to address this evidence gap. Furthermore, the physiological findings in people without OSA showed that males are more arousable than females. This information may be of value when considering personalisation of clinical treatment. Future research of POSA will need to consider the arousability phenotype when planning treatment options.Open Acces

Investigating Multimedia Strategies to Aid L2 Listening Comprehension in EFL Environment

Arab learners may experience a great difficulty in attending to listening comprehension activities due to different chunks of the target language they are engaged in. As such, learners should be informed as to what is the best technique that helped them overcome this difficulty. This paper attempts to investigate the efficacy of using visual multimedia technique (i.e., video mode + test) in multimedia language settings to aid L2 listening comprehension. Sixty adult students watched video conversations provided with texts plus animation for 10 modules, while the control group listened to the same material delivered by audio tracks for the same period of time. The students were post-tested immediately after treatment and retested after delayed point of time. The students’ perceptions towards the use of multimedia modes were gathered using a survey. The quantitative results showed a significant effect of visual stimulus over the auditory mode in gaining L2 listening comprehension. Limitations and directions for future research are summarized in this study

Incorporating knowledge sharing behaviour in a knowledge management system for academic institutions / Alsaleh Saad Abdullah R

This thesis proposed a knowledge management system framework for academic institutions based on academicians’ knowledge sharing behaviour. The current knowledge management systems in higher learning institutions do not capture and represent most of the knowledge types in the academic institutions and little attention has been given to human aspects. A qualitative research approaches were employed in this research. This research was carried out in four stages which are: knowledge acquisition; data collection; data analysis and findings; and development of a knowledge management system framework. The research site was at Malaysia’s largest academic institution in terms of size and population. The study discovered two types of knowledge shared among academicians; namely: corporate knowledge and social knowledge. The knowledge sharing networks among the academicians include Community of Practice network, Personal network, and Business Club network

Study on mitigation factors for controlling cost overrun in construction project

The construction industry plays an influential role in the socio-economy of a country. In Malaysia also, the construction industry is one of essential industry participating significantly in the growth of socio-economic development. The construction industry in Malaysia are still facing a significant issue of cost overrun, where only 46.8% of public sector and 37.2% of private sector projects were completed within the specified budget. The issue of cost overrun has become a serious concern to investors, which needs stern attention and in-depth research to put forward solutions to this issue. The objectives of this research are to investigate current mitigation practices for controlling cost overrun in construction projects, to identify mitigation problems for controlling cost overrun in construction projects and to recommend key mitigation factors for controlling cost overrun in construction projects. The research was take place in Johor Bahru the capital of Johor State. The research based on quantitative research by using questionnaire to carry out the research. The questionnaire was designed based on the objectives each objective has ten statements with one option, in order to get accuracy results. A total of 80 questionnaires were gathered from a total of 220 contractors of G7 distributed at Johor Bahru. Data collected was analysed using the Statistical Package for the Social Science 22.0 software. The method of analysis that had being used in this research is percentage, frequency and means score value. There is dissatisfaction about the current mitigation practices for controlling cost overrun. Moreover, the study proves that there are mitigation problems faced by contractors. Furthermore, majority of the respondents agreed to the recommendation provided by the study to control cost overrun. Respondents have been recommended that may will be effectiveness to keep construction project within budget. In conclusion, the research has been introduced and recommended major mitigation factors for controlling cost overrun may will help construction industry achieve project within budget