1,259 research outputs found

    Intercanthal distance of a Sudanese population sample as a reference for selection of maxillary anterior teeth size

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    Background: The choice of the size of artificial teeth takes an important place in the removable prosthodontic treatment. However, the standards or proportions commonly used as a guide have been developed mainly on Caucasian populations. Objectives: to investigate the relationship between intercanthal distance and the anterior maxillary teeth size in Sudanese population. Methods: This is a descriptive cross sectional study conducted in 114 subjects, (45 males - 69 females), from Khartoum and Juba Universities. The age range was from 18-46 years. The intercanthal distance (I.C.D) was the measurement taken between the median angles of the palpabral fissure. Maxillary intercanine distance was obtained by measuring a line from the tip of the canine on one side, to the canine on the other side. An electronic digital caliper (Narex – Czechoslovakia) was used for all measurements. Data were analyzed using Person chi–square test.Results: a significant correlation is found between intercanthal distance and maxillary intercanine distance in all subjects (P-value 0.015), and in females who had a (P-value of 0.006). Maxillary intercanine distance may be estimated by dividing I.C.D by factor 0.9. Conclusion: These results could be used as a helpful guide for selection of anterior teeth width in the Sudanese population

    IPC2008-64685 A NOVEL TWO-PHASE GAS\LIQUID SLUG FLOW MEASUREMENT SYSTEM USING A T-JUNCTION SEPARATOR AND ULTRASONIC MEASUREMENTS

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    ABSTRACT Over the last decade, the development and deployment of in-line multiphase flow metering systems has been a major focus worldwide. Accurate measurement of multiphase flow in the oil and gas industry is difficult because it occurs in wide range of flow regimes and multiphase meters do not generally perform well under the intermittent slug flow conditions which commonly occur in oil production. A novel ultrasonic multiphase metering concept has been proposed and investigated which measures the flow rates of the liquid and gas phases from ultrasonic measurements made in two different flow regimes -partially separated and homogeneous -in the same measurement system and fuses the data from the different flow regimes to obtain improved overall measurement accuracy. The system employs a partial gas/liquid separation using a T-junction configuration and a combination of Doppler and cross correlation. The partially separated flow regimes uses ultrasonic cross correlation measurement for the liquid flow measurement which has gas entrained within it. The homogeneous regime employs ultrasonic Doppler method. This approach has been tested on water/air flows on a 50mm facility in the Department of Process and Systems Engineering. The liquid and gas flowrate measurements using the proposed techniques were compared with a reference measurement and good agreements between these two measurements were obtained with error ranging from ± 2 % and 10%, respectively. Such a performance offers the potential for an in-line multiphase flowmeter with improved performance

    An investigation of gender and generational differences in attitudes toward the importance of a college degree in the UAE

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    © 2017, Emerald Publishing Limited. Purpose: This study examines attitudes toward higher education for men and women among male and female students and parents in the United Arab Emirates (UAE) and demonstrates gender differences in parent and student expectations about the importance of higher education. Design/methodology/approach: This quantitative study examines attitudes toward higher education among 461 matched students and parents (total sample size 1442 respondents) in six higher education institutions in the United Arab Emirates (UAE) and demonstrates gender differences between parent and student perceptions. Findings: In general, attitudes about the importance of a college degree were high and stable, except that younger, more recent female graduates were more likely to disagree that family traditions were threatened by women completing a college degree. Socio-demographic variables were associated with more favorable attitudes about the value of education for global leadership, the importance of a college education for both men and women and gender equality. Research limitations/implications: Six higher education institutions were represented in the sample so external validity can be improved by studying these variables in other sample groups across the nation, region and globe. In addition, including additional types of universities, e.g. distance learning, technical, research and military, would indicate if the findings are generalizable to a broader range of institutions of higher education. There are opportunities for future comparative studies to examine the relevance of these findings across cultures and government initiatives to build national human resource capital and to consider other aspects of intergenerational relationships, attitudes and behaviors. Originality/value: The authors examine perceived implications of the value of higher education on different arenas of men and women’s lives among the Emirates. Additionally, we focus on whether their attitudes vary by gender and generation

    Effect of intensive melt shearing on the formation of Fe-containing intermetallics in LM24 Al-alloy

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    Fe is one of the inevitable and detrimental impurities in aluminium alloys that degrade the mechanical performance of castings. In the present work, intensive melt shearing has been demonstrated to modify the morphology of Fe-containing intermetallic compounds by promoting the formation of compact α-Al(Fe,Mn)Si at the expense of needle-shaped β-AlFeSi, leading to an improved mechanical properties of LM24 alloy processed by MC-HPDC process. The promotion of the formation of α -Al(Fe, Mn)Si phase is resulted from the enhanced nucleation on the well dispersed MgAl 2O 4 particles in the melt. The Fe tolerance of LM24 alloy can be effectively improved by combining Mn alloying and intensive melt shearing

    Patient radiation exposure from embolo-sclerotherapy of peripheral vascular malformations

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    Objective: Embolo-sclerotherapy (EST) is the mainstay therapy for peripheral vascular malformations which involves the exposure of patients to ionizing radiation. We aimed to analyze the radiation exposure to patients from EST of peripheral vascular malformations over five years in a single specialist center. / Methods: All patients who had EST performed in a single specialist center for peripheral vascular malformations between January 1st 2013 and January 8th 2018 were identified from a prospectively collected database. Data collection included basic demographics, procedure date, anatomical site, type of vascular malformations and procedural details. Radiation exposure, measured in dose-area product (DAP) and fluoroscopy times, of all patients identified to have EST during the period were retrospectively reviewed. Statistical analysis was performed using Mann-Whitney U and Kruskal-Wallis tests for comparison between subgroups. P<0.05 was considered significant. / Results: A total of 237 patients (median age 30 years; range 1 – 73 years) underwent 419 ESTs during the study period. Of these, 61 (25.7%) patients had arteriovenous malformations (AVM) and underwent 140 (33.4%) ESTs. Meanwhile, 176 (74.3%) patients had venous and lymphatic malformations and underwent 279 ESTs (66.6%). Patients with AVMs had a median of 2 procedures (range 1 - 13), compared to a median of 1 (range 1 - 6) for venous and lymphatic malformations within the study period. The median DAP for single and cumulative EST for peripheral vascular malformations were 1.26 Gycm2 (range 0.00 – 698.36 Gycm2) and 1.91 Gycm2 (range 0.00 – 1300.24 Gycm2), respectively. Whereas, the median fluoroscopy time for single and cumulative EST were 19 seconds (range 1 – 3846 seconds) and 30 seconds (range 1 – 5843 seconds), respectively. Significantly higher patient radiation exposure, in DAP and fluoroscopy times, were measured for single and cumulative EST for AVM when compared with venous and lymphatic malformation (both p <0.01; Mann Whitney U). A significant difference in DAP but not fluoroscopy time was found when anatomical areas of vascular malformations were compared. / Conclusions: Patient radiation exposure for EST of peripheral vascular malformations, measured in DAP and fluoroscopy times, appeared to be generally less than those reported for endovascular arterial and deep venous interventions in the literature. However, some patients with peripheral vascular malformations received relatively high radiation doses. Further studies to investigate the risk factors and long-term side-effects of radiation exposure in these patients and strategies to reduce it are required

    Using keystroke logging to understand writers’ processes on a reading-into-writing test

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    Background Integrated reading-into-writing tasks are increasingly used in large-scale language proficiency tests. Such tasks are said to possess higher authenticity as they reflect real-life writing conditions better than independent, writing-only tasks. However, to effectively define the reading-into-writing construct, more empirical evidence regarding how writers compose from sources both in real-life and under test conditions is urgently needed. Most previous process studies used think aloud or questionnaire to collect evidence. These methods rely on participants’ perceptions of their processes, as well as their ability to report them. Findings This paper reports on a small-scale experimental study to explore writers’ processes on a reading-into-writing test by employing keystroke logging. Two L2 postgraduates completed an argumentative essay on computer. Their text production processes were captured by a keystroke logging programme. Students were also interviewed to provide additional information. Keystroke logging like most computing tools provides a range of measures. The study examined the students’ reading-into-writing processes by analysing a selection of the keystroke logging measures in conjunction with students’ final texts and interview protocols. Conclusions The results suggest that the nature of the writers’ reading-into-writing processes might have a major influence on the writer’s final performance. Recommendations for future process studies are provided

    Evaluation of the Relative Tectonic Activity of the Adıyaman fault within the Arabian-Anatolian plate boundary (eastern Turkey)

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    The left-lateral strike-slip Adıyaman fault is located in eastern Turkey within the plate boundary deformation zone between Arabia and Anatolia. The Adıyaman fault is a major splay from the East Anatolian Fault (EAF), one of the most important tectonic structures in the Eastern Mediterranean region. These faults are consequence of the collision between the Arabian and Anatolian plates and the resulting westward tectonic escape of Anatolia. Although the EAF has been intensively studied since its discovery in the late 1960s, little is known about the Adıyaman fault and its tectonic activity. In this study, we extract geomorphic indices including mountain-front sinuosity (Smf), valley floor width-to-height ratio (Vf), stream length-gradient (SL), catchment Asymmetry Factor (AF) and hypsometric integrals and curves (HI and HC) to evaluate the relative tectonic activity of the Adıyaman fault. These three geomorphic indices (AF, HI, and HC) are averaged to define an index for Relative Tectonic Activity (RTA) that allows the Adıyaman fault to be divided into categories of low, moderate and high RTA. The results confirm that the Adıyaman fault is an active fault with high to moderate Quaternary tectonic activity. However, this fault is of minor importance on accommodating plate boundary deformation, as evidenced by the recent crustal motions determined by GPS studies. Nevertheless, it is worthwhile to note that the Adıyaman fault still poses a significant seismic hazard for the region despite its relatively moderate tectonic activity

    Linking tests of English for academic purposes to the CEFR: the score user’s perspective

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    The Common European Framework of Reference for Languages (CEFR) is widely used in setting language proficiency requirements, including for international students seeking access to university courses taught in English. When different language examinations have been related to the CEFR, the process is claimed to help score users, such as university admissions staff, to compare and evaluate these examinations as tools for selecting qualified applicants. This study analyses the linking claims made for four internationally recognised tests of English widely used in university admissions. It uses the Council of Europe’s (2009) suggested stages of specification, standard setting, and empirical validation to frame an evaluation of the extent to which, in this context, the CEFR has fulfilled its potential to “facilitate comparisons between different systems of qualifications.” Findings show that testing agencies make little use of CEFR categories to explain test content; represent the relationships between their tests and the framework in different terms; and arrive at conflicting conclusions about the correspondences between test scores and CEFR levels. This raises questions about the capacity of the CEFR to communicate competing views of a test construct within a coherent overarching structure

    The Uniformity Principle vs. the Disuniformity Principle

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    The pessimistic induction is built upon the uniformity principle that the future resembles the past. In daily scientific activities, however, scientists sometimes rely on what I call the disuniformity principle that the future differs from the past. They do not give up their research projects despite the repeated failures. They believe that they will succeed although they failed repeatedly, and as a result they achieve what they intended to achieve. Given that the disuniformity principle is useful in certain cases in science, we might reasonably use it to infer that present theories are true unlike past theories. Hence, pessimists have the burden to show that our prediction about the fate of present theories is more likely to be true if we use the uniformity principle than if we use the disuniformity principle
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