Conceptual Understanding for Systems of Linear Equations: Difficulties and Challenges

The conceptual understanding of algebraic concepts is challenging to students, adds to the challenge of teaching them. This study aimed to reveal the level of conceptual understanding about Systems of Linear Equations (SLEs) and its difficulties that faced students while they solving problems. The study sample consisted of (68) male and female students of linear algebra course. The conceptual understanding test was prepared with two qualitative and quantitative rubrics to classify students’ levels. The study results showed a decrease in the conceptual understanding of SLEs in general, and in the area of realizing the relationships between concepts related to SLEs in particular. In contrast, the level of conceptual understanding of students was medium in the context of multiple representations. The results also showed many difficulties that students face while solving SLEs. The study recommended the need to focus on the conceptual understanding of concepts related to SLEs and to use multiple representations and connect them together when teaching mathematical concepts

The Effectiveness of Using the Model Eliciting Activities (MEAs) in Improving the Ability to Solve Mathematical Problems and Self-Efficacy among Female Students in Eighth Grade in the Sultanate of Oman

ملخص: هدفت الدراسة إلى تقصّي فاعلية استخدام النموذج القائم على استنباط الأنشطة (MEAs) في تحسين القدرة على حلّ المسائل الرياضية والكفاءة الذاتية لدى طالبات الصف الثامن الأساسي بسلطنة عمان، واستُخدم التصميم شبه التجريبي، وقد بلغ عدد أفراد الدراسة 52 طالبة وُزِّعوا بالتساوي على مجموعتي الدراسة: التجريبية والضابطة. ولتحقيق أهداف الدراسة؛ أُعّدت أدواته المتمثلة في: اختبار القدرة على حل المسائل الرياضية، المكوّن من 6 أسئلة مقالية، ومقياس الكفاءة الذاتية في حل المسائل الرياضية، المكوّن من 27 فقرة، أظهرت النتائج وجود فروق ذات دلالة إحصائية عند مستوى (05. = α) في كلّ من اختبار القدرة على حل المسائل الرياضية، ومقياس الكفاءة الذاتية في حل المسائل الرياضية، لصالح المجموعة التجريبية، وفي ضوء هذه النتائج، أوصت الدراسة بعدة توصيات، منها: الاستفادة من النموذج التعليمي القائم على استنباط الأنشطة (MEAs)، في تدريس الرياضيات.Abstract: The study aims to investigate the effectiveness of using the Model Eliciting Activities (MEAs) on the ability to solve mathematical problems and self-efficacy among female students in eighth grade in the Sultanate of Oman. A quasi-experimental research design was used. The sample of the study consisted of 52 female students. It was divided equally into two groups: an experimental group and a control group. To achieve the objectives of the study, an instrument was developed to measure the students’ ability to solve mathematical problems with test consisting of 6 essay questions. In addition, a questionnaire of self-efficacy in solving mathematical problems was used consisting of 27 items. The results showed statistically significant differences at (α=.05) in both abilities to solve mathematical problems, self-efficacy in solving mathematical problems scale due to the teaching method, in favor of the experimental group. Considering these results, the study suggested several recommendations such as benefiting from the educational model based on (MEAs), in mathematics teaching

Preparation and characterization of microencapsulated phase change materials for use in building applications

A method for preparing and characterizing microencapsulated phase change materials (MPCM) was developed. A comparison with a commercial MPCM is also presented. Both MPCM contained paraffin wax as PCM with acrylic shell. The melting temperature of the PCM was around 21 C, suitable for building applications. The M-2 (our laboratory made sample) and Micronalr DS 5008 X (BASF) samples were characterized using SEM, DSC, nano-indentation technique, and Gas Chromatography/Mass spectrometry (GC-MS). Both samples presented a 6 m average size and a spherical shape. Thermal energy storage (TES) capacities were 111.73 J g 1 and 99.3 J g 1 for M-2 and Micronalr DS 5008 X, respectively. Mechanical characterization of the samples was performed by nano-indentation technique in order to determine the elastic modulus (E), load at maximum displacement (Pm), and displacement at maximum load (hm), concluding that M-2 presented slightly better mechanical properties. Finally, an important parameter for considering use in buildings is the release of volatile organic compounds (VOC's). This characteristic was studied at 65 C by CG-MS. Both samples showed VOC's emission after 10 min of heating, however peaks intensity of VOC's generated from M-2 microcapsules showed a lower concentration than Micronalr DS 5008 X

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

The Degree of TIME Management Skills Among School Principals in Irbid Qasabah From the Teachers' Viewpoint

This study sought to identify the extent to which school principals in Irbid Qasabah Directorate of Education possessed time management skills from teachers' viewpoint. And to identify the nature of the association between the principals' rate of time used and the task's significance according to their estimation. To achieve the study goals, the descriptive approach was utilized, and a questionnaire was designed with (40) items. It was administered to the study sample (n = 208) of male and female teachers from Irbid Qasabah. The findings of the study indicated that the principals of both public and private schools in Irbid Qasabah had a high level of time management skills. The findings also showed that there were no statistically significant differences between the means of the participants' estimates attributed to the difference in the variables of academic qualification and experience. Except for the gender variable, where there were statistically significant differences showing that females outperformed males

Methods for the Synthesis of Phase Change Material Microcapsules with Enhanced Thermophysical Properties—A State-of-the-Art Review

Thermal energy storage (TES) has been identified by many researchers as one of the cost-effective solutions for not only storing excess or/wasted energy, but also improving systems’ reliability and thermal efficiency. Among TES, phase change materials (PCMs) are gaining more attention due to their ability to store a reasonably large quantity of heat within small temperature differences. Encapsulation is the cornerstone in expanding the applicability of the PCMs. Microencapsulation is a proven, viable method for containment and retention of PCMs in tiny shells. Currently, there are numerous methods available for synthesis of mPCMs, each of which has its own advantages and limitations. This review aims to discuss, up to date, the different manufacturing approaches to preparing PCM microcapsules (mPCMs). The review also highlights the different potential approaches used for the enhancement of their thermophysical properties, including heat transfer enhancement, supercooling suppression, and shell mechanical strength. This article will help researchers and end users to better understand the current microencapsulation technologies and provide critical guidance for selecting the proper synthesis method and materials based on the required final product specifications.</jats:p

Methods for the Synthesis of Phase Change Material Microcapsules with Enhanced Thermophysical Properties&mdash;A State-of-the-Art Review

Thermal energy storage (TES) has been identified by many researchers as one of the cost-effective solutions for not only storing excess or/wasted energy, but also improving systems&rsquo; reliability and thermal efficiency. Among TES, phase change materials (PCMs) are gaining more attention due to their ability to store a reasonably large quantity of heat within small temperature differences. Encapsulation is the cornerstone in expanding the applicability of the PCMs. Microencapsulation is a proven, viable method for containment and retention of PCMs in tiny shells. Currently, there are numerous methods available for synthesis of mPCMs, each of which has its own advantages and limitations. This review aims to discuss, up to date, the different manufacturing approaches to preparing PCM microcapsules (mPCMs). The review also highlights the different potential approaches used for the enhancement of their thermophysical properties, including heat transfer enhancement, supercooling suppression, and shell mechanical strength. This article will help researchers and end users to better understand the current microencapsulation technologies and provide critical guidance for selecting the proper synthesis method and materials based on the required final product specifications