The Impact of Using Distributed Practice on Some Elements of Physical Fitness and Some Anthropometric Variables among the Students of the Physical Education Courses at Al-Zaytoonah University of Jordan

This study aimed at identifying the impact of the use of distributed practice on some of the elements of physical fitness (transitional speed, muscle ability, maximum strength, flexibility, agility) and some anthropometric variables (body weight, abdominal fat, below the blade bone, behind the hummers). The researcher used the empirical method, and the study sample included 15 students enrolled in the course of physical education at Al-Zaytoonah University. Après-measurement was conducted, and thenthe training program was applied for a period of 8 weeks at a rate of three training units per week.The results of the study showed improvement and development in the physical fitness elements (transitional speed, muscle ability, maximum strength, flexibility, agility) and in the anthropometric variables (body weight, abdominal fat, upper arm fat). According to that, theresearcher recommends the use of distributed practice to improve and develops physical fitness elements and anthropometric variables. The researcher also recommends conducting other studies regarding the rest of physical fitness elements and physical and anthropometric variables

Heat Absorbers based on Recycled Polyethylene and Paraffin Wax for Energy Storage

The building sector is one of the main sectors in Qatar; however, it consumes a huge portion of primary energy sources. Today, there is a worldwide trend to utilize renewable sources of energy to cover buildings’ energetic needs using local climate conditions. The common source of energy, the sun, can be efficiently utilized in covering energetic supplies of buildings. To be able to consume energy of the sun, various components and materials are designed. This thesis is focused on the preparation and complex physical characterization of heat absorbers based on Phase Change Materials Heat Absorbers (PCM-HA). The materials are designed based on recycled high-density polyethylene (W-HDPE) obtained directly from a local industrial company in Qatar, paraffin wax and expanded graphite (EG) which can all be used together as the main components in improving the passive heating or cooling of buildings. Thus, this work is directly related to environmental protection and energy conservation in buildings. A big attention is given to the long term stability of the PCM-HA. The materials were artificially aged at selected conditions (temperature, UV irradiation, humidity) to characterize their long term behavior. This type of characterization was rarely reported in literature. Thus, the obtained results conveyed valuable benefits. This long-term experimentation confirmed the significant reduction in paraffin leakage from the thermal system up to 9.83%. Thus, this also confirms the high ability of the materials to absorb and release reaching 70 J/g of heat energy. Samples mixed with EG did not lose their mechanical integrity and compactness even after 100 days of accelerated artificial aging. Adding to this, various PCMs are applicable not only in building sectors, but also in thermal protection of electronic devices. For this reason, the dielectric behavior of the developed materials are explored and results confirmed an increase in electrical conductivity due to addition of EG to the materials

Autonomous Learning Levels of Students Majoring in EFL and the Role of their Teachers in Developing Autonomous Learning

Learning a foreign language is greatly enhanced when learners are autonomous and enjoy a high level of autonomy in a myriad of activities. The current study investigated the levels of autonomy among senior non-native English students and the role of their university instructors in promoting autonomous learning. More specifically, the study examined the autonomous learning levels of 4th year non-native English majors and the role that the university instructors are playing in developing these non-native English majors’ autonomous levels from students' perspectives. The data was gathered by  semi-structured interviews. The sample of the study consists of 30 out of 100 students. Data collected were analyzed qualitatively using the thematic analysis method. The results of the study showed that generally non-native English majors enjoy a high level of autonomy in some activities ranging from the beginning to intermediate level. Pertaining to their instructors’ roles in developing and improving their level of autonomy, the results showed that some students do not consider it a teacher’s responsibility, whereas  others indicated that it is incumbent upon the instructors to guide and train students on how to be autonomous and improve their level of autonomy. The reasons behind the results of the study, implications and recommendations for non-native English majors and university instructors are discussed

Recycled polyethylene/paraffin wax/expanded graphite based heat absorbers for thermal energy storage: An artificial aging study

An artificial aging study of novel heat absorbers based on phase change materials (PCMs) prepared from recycled high-density polyethylene (HDPE), paraffin wax (PW), and expanded graphite (EG) was investigated. The optimal composition of PCMs contained 40 wt% HDPE, whereas the paraffin wax content ranged from 40 to 60 wt% and the expanded graphite content ranged from 5 to 15 wt%. PCMs were artificially aged through exposure to UV irradiation, enhanced temperature, and humidity. It was clearly demonstrated that the addition of EG to PCMs led to the suppression of PW leakage and improved the photooxidation stability of the PCMs during the aging process. The best performance was achieved by adding 15 wt% of EG to the PCMs. The sample shows a leakage of paraffin wax below 10%, retaining a melting enthalpy of PW within PCMs of 54.8 J/g, a thermal conductivity of 1.64 W/mK and the lowest photooxidation, characterized by an increase in the concentration of carbonyl groups from all investigated materials after artificial aging. Furthermore, PCMs mixed with EG exhibited good mechanical properties, even after 100 days of exposure to artificial aging. Finally, this work demonstrates a justification for the use of recycled plastics in the formation of PCMs.This research was funded by an NPRP grant No: NPRP10-0205-170349 from the Qatar National Research Fund (a member of the Qatar Foundation)

Sustainable innovation in membrane technologies for produced water treatment: Challenges and limitations

Discharged water from the oil and gas fields is a common type of wastewater called produced water (PW). It consists of different combinations of salinities, oils, and mineral deposits. Growing industrial demand, accelerated urbanization, and rapid population growth are putting enormous strain on the world?s water supply. Based on sustainable freshwater supplies, North Africa, the Middle East, and South Asia confront the ultimate water shortages threat. Proper implementation of innovative membrane technologies in wastewater treatment is considered a solution towards tackling water insecurity and sustainability. Different types of innovative membrane technologies used for produced water treatment were considered in this work. A framework of innovative membrane technology was studied for industrial wastewater with direct contribution to the environmental and economical sustainability factors, taking into consideration grand challenges and limitations in energy costs and environmental constraints. Treated produced water can be utilized in irrigation providing many benefits only if the desalination sector is mature and fully developed.Scopu

Outcomes in patients undergoing urgent colorectal surgery

Background - Urgent surgery for acute intestinal presentations is generally associated with worse outcomes than elective procedures. This study assessed the outcomes of patients undergoing urgent colorectal surgery. Methods - Patients were identified from a prospective database. Surgery was classified as urgent when performed as soon as possible after resuscitation and usually within 24 h. Outcome measures included 30 days mortality, return to theatre, anastomotic leak and overall survival. Results - Two hundred forty-nine patients were included in the analysis. Median age was 65 years (interquartile range 48–74). The most common presentations were obstruction (52.2%) and perforation (23.6%). Cancer was the disease process responsible for presentation in 47.8% of patients. Thirty-day mortality was 6.8%. Age (odds ratio 1.08 95% confidence interval (CI) 1.02–1.15; P = 0.01), American Society of Anesthesiologists 4 (odds ratio 7.14 95% CI 1.67–30.4; P = 0.008) and cancer (odds ratio 6.61 95% CI 1.53–28.45; P = 0.011) were independent predictors of 30 days mortality. Relaparotomy was required in six (2.4%) cases. A primary anastomosis was performed in 156 (62.6%) patients. Anastomotic leak occurred in four (2.5%) patients. In patients with cancer, overall 5-year survival was 28% (95% CI 19–37), corresponding to 54% (95% CI 35–70) for stages I and II, 50% (95% CI 24–71) for stage III and 6% (95% CI 1–17) for stage IV disease. Urgent surgery was independently associated with worse overall survival (hazard ratio 2.65; 95% CI 1.76–3.99; P < 0.001). Conclusion - In patients undergoing an urgent resection within a colorectal unit, performing a primary anastomosis is feasible and safe in the majority, relaparotomies are required in a minority and urgent surgery is an important predictor of worse prognosis in those with colorectal cancer

Experimental Investigations of Gas Kick for Single and Two-Phase Gas-liquid Flow in near Horizontal Wells

Multiphase flow in pipelines is of great importance and broadly used in several industries for various applications. A multiphase flow is a complex physical phenomenon where more than one phase occurs. In oil and gas exploration process, more attention has been given to the well drilling operation to fulfill the extreme high demand of natural gas. Well drilling operation and technology has transformed to ultra-high pressure and high temperature reservoirs. This transformation has negatively impacted the drilling conditions and the safety of the drilling rig, as a gas kick would become more likely to occur at these extreme conditions. The resulting uncontrolled gas kicks may ignite and explode causing dramatic blowouts associated with very serious consequences, including financial losses, damaging the environment, and loss of personnel's lives. The early detection of a gas kick is therefore essentially needed for timely response with appropriately well control measures

Natural aging of shape stabilized phase change materials based on paraffin wax

Natural aging of shape-stabilized phase change materials containing linear low density polyethylene (LLDPE), paraffin wax and expanded graphite (EG) in Qatari climate has been studied. It was found that expanded graphite significantly improved the performance of prepared SSPCMs in multiple ways. Firstly, EG suppressed leakage of paraffin wax from the compact shape of SSPCMs. The addition of 15 wt% of EG to shape stabilized phase change materials (SSPCMs) containing 50 wt% of wax caused a decreasing in the leakage of wax by 50% over 210 days of natural aging. Secondly, ?expanded graphite enhanced the photochemical stability of the blends; this was confirmed by FTIR analysis, where carbonyl index decreased with EG content. 1 2017 Elsevier LtdThis work was allowed by NPRP grant No.: 4 - 465 - 2-173 from the Qatar National Research Fund (A Member of The Qatar Foundation). The statements made herein are solely the responsibility of the authorsScopu