Exploring the Impact of Visual Heat Conduction Paths on Thermal Conductivity of Polymer Composites and the Practical Applications.

The theory of heat conduction paths has been widely recognized and widely studied in the research about the thermal conductivity of thermal conductive polymer composites at present. Encapsulating polymer pellets with thermally conductive fillers and processing them into thermally conductive polymer composites is a simple and effective method for constructing heat conduction paths. It is meaningful to investigate the related heat conduction mechanism of this method. Otherwise, this approach can significantly preserve the performance of the polymer substrate, making it highly valuable for practical material applications. In this work, polyethylene-octene elastomer (POE) pellets were encapsulated with thermal conductive fillers by physical absorption. Subsequently, the composite films containing heat conduction paths were fabricated using the encapsulated POE pellets through a heating press. Alumina (Al2O3), boron nitride (BN), and alumina/boron nitride hybrid (Al2O3/BN) fillers were used to prepare Al2O3@POE, BN@POE, and BN/Al2O3@POE composite films to investigate the influence of filler shapes on heat conduction path construction. The influence of the constitute and density of heat conduction paths on the thermal conductivity of composite films was analyzed by infrared thermal imaging, finite element analysis, and thermal resistance theory in detail. Owing to the reserved good adhesion and flexibility of the POE substrate, the composite films could be directly used as thermal interface materials for chip cooling, which presented a good heat dissipation effect. Furthermore, a series of integrated composite materials were prepared by the combination of encapsulated pellets with various functional films (copper foil, aluminum foil, and graphite sheet) through a one-pot heating press, exhibiting a good electromagnetic shielding effect. The performance of the composites and the corresponding preparation method demonstrate the strong significance of this research for practical applications.

A qualitative assessment of medical students' readiness for virtual clerkships at a Qatari university during the COVID-19 pandemic.

BACKGROUND: This study aims to qualitatively examine the readiness of medical students to change to virtual clerkship (VC) during the pandemic, from both the faculty and students' perspectives. METHODS: A qualitative study was conducted based on the framework of readiness to change. Focus group discussions with students, and semi-structured interviews with clinical faculty members were done using appropriate online platforms. Transcripts were then analyzed using inductive-deductive approach. RESULTS: Twelve themes emerged which are (1) Perceptions about the university's decision and its communication to students, (2) A Perceived lack of clinical experience, (3) Students' role as members of the medical team facing the pandemic, (4) Student safety, (5) Quality and design of VC and the skills it offered, (6) Belief in own ability to succeed in the VC, (7) Confidence that VC would reach its goals, (8) New enhanced learning approaches, (9) Preparing students for new types of practice in the future (10) Acquired skills, 11) Academic support and communication with faculty and college, and 12) Psychological support. Medical students showed limited readiness to undertake a virtual clerkship and not play their role as healthcare professionals during the pandemic. They perceived a huge gap in gaining clinical skills virtually and asked for a quick return to training sites. CONCLUSION: Medical students were not ready for virtual clerkships. There will be a need to integrate novel learning modalities such as patient simulations and case-based learning in order to meet future demands of the medical profession and enhance the efficiency of virtual clerkships.

Does problem-based learning facilitate enactment of learner agency in undergraduate dental curricula? A Q study.

INTRODUCTION: Addressing a literature gap on leaner agency in health profession education, this study explores students' perceptions on which aspects of a problem-based learning (PBL) environment cradle their leaner agency enactment. METHODS: Thirty-eight students from a newly established undergraduate dental medicine programme in Qatar participated in the study. Q methodology was adopted to collect and analyse data both qualitatively and quantitatively. A 40-statement Q-set was established based on a proposed conceptual framework of learner agency in PBL, including three dimensions-intrapersonal, behavioural and environmental. RESULTS: Q methodological factor analysis identified four significantly different student viewpoints, which underscored participants' enactment of learner agency addressing the intrapersonal, behavioural and environmental dimensions of the conceptual framework. Despite differences in opinion regarding sources of learner agency, the four student viewpoints unanimously underscore the importance of PBL facilitators' expertise to nurture and develop agency amongst undergraduate students. Post-sorting qualitative data further confirmed the quantitative analysis. Time constraints and workload were identified as the main challenges by the participants. CONCLUSIONS: This study explored enactment of learner agency as perceived by undergraduate dental students in a PBL curriculum. The findings of this study provide new insights into participants' subjective understanding of learner agency in a PBL curriculum in dentistry. Structured support is needed for students having no prior PBL experiences to develop their learner agency at both intrapersonal and behavioural (self-regulated learning) dimensions, and to ensure they interact with their learning environment proactively.

Development of self-regulation amongst dental students in problem-based learning curricula: A qualitative study.

AIMS: To explore the value of problem-based learning in the development of self-regulation amongst undergraduate dental students. MATERIALS AND METHODS: A qualitative approach using focus groups was used to explore the perceptions and experiences of the participants regarding the role of problem-based learning (PBL) in promoting self-regulation in undergraduate dental education. The study was carried out at a newly established dental institution in Qatar. Purposive sampling technique was used to recruit the participants. Invitations to potential participants were sent by e-mail through appropriate professional channels. All focus groups were transcribed verbatim, and data were imported into NVivo 12 and analysed thematically. RESULTS: A total of five focus groups were conducted with 37 participants which included 27 females and seven males from two different cohorts. Participants expressed their views on a range of issues related to the self-regulation in problem-based learning and also provided recommendations to enhance the learning experiences of students. PBL was perceived to be an appropriate and effective strategy to support student autonomy in construction of knowledge and developing problem-solving and interpersonal skills. However, the workload of the students can impact adversely on their motivation and time management skills. CONCLUSIONS: This study provides useful insights into the concept of self-regulation in problem-based learning environments as perceived by the stakeholders at a newly established dental institution. The findings of this study may offer clarity on how problem-based learning can be best utilised to promote self-regulation in undergraduate dental education.

Health educators' professional agency in negotiating their problem-based learning (PBL) facilitator roles: Q study.

BACKGROUND: University educators are expected to cope with emerging situations and complex issues in teaching and learning, and this requires them to be agentic and proactive. While professional agency of health educators has not been investigated adequately, this study explores health educators' perception of their enactment of professional agency in the PBL facilitation process in a postpandemic context. METHODS: Forty PBL facilitators from medical and dental programs in Qatar University participated in the study during the fall semester of 2021, after resuming in-person PBL sessions. To collect and analyse data both qualitatively and quantitatively, Q methodology was employed. A 33-statement Q-set was established based on a proposed theoretical framework of professional agency in PBL facilitation, which included three dimensions-intrapersonal, action, and environment. RESULTS: Q factor analysis identified five significantly different viewpoints regarding how PBL facilitators perceive their professional agency sources, namely, (1) institutional resources, (2) policy guideline, (3) making efforts to improve support for students, (4) beliefs on PBL effectiveness, and (5) agentic actions. While four of the viewpoints were positive, participants with the second viewpoint reported negative perceptions and described lack of interest in facilitation work. All three dimensions of the framework were addressed and indicated complexity and interrelatedness of agency enactment. Consensus was observed regarding the need for more professional learning activities for faculty involved in PBL facilitation as source of professional agency. DISCUSSION: The results revealed a high variation of participants' perceptions of professional agency enactment throughout the three dimensions, indicating the need for establishing a common understanding of PBL facilitation work in a given context. For practical implications, further institutional efforts are required to support professional learning for PBL facilitation in a postpandemic context. Alternate approaches highlighting enforcement of agentic actions in all dimensions of intrapersonal values, stance and action taking, and active interactions with students, colleagues, and institutional environments are crucial. Q methodology provides new conceptual and empirical insights to explore the subjectivity of actors in health education.

A qualitative enquiry into dental students' perceptions of dentistry as a career choice in the State of Qatar.

BACKGROUND: Career choice is a complex, multifaceted process affecting all aspects of life. Motivational factors of aspiring dentists are crucial to inform institutions and aid with the admission process. The aim of this study was to explore undergraduate dental students' perceived motivation for their career choice in the first dental institution in the State of Qatar to bridge the gap in knowledge in this area. METHODS: Homogeneous purposive sampling technique was employed to collect data from all year 2 and year 3 undergraduate dental students to gain a deeper insight into their motivation of career choice. An explorative qualitative method using face-to-face focus group sessions were utilized. All focus groups were conducted in English and contained a moderator and observer. A topic guide was used to ensure data collection standardization. Participants' views were recorded and filed notes obtained. Data was transcribed and analysis performed utilizing an inductive thematic approach. RESULTS: A total of 34 students (89.5%) from year 2 and 3 participated in the focus groups. Data analysis revealed six main themes emerging from this study namely; altruism and patient care, family influence factors, childhood aspirations, hands-on practical skills, professional and social status, and the opportunity to reconsider and transfer. Based on frequency, altruism, opportunities to learn hands-on practical skills and professional status appeared to be the main drivers influencing students' choice of dentistry as a professional career. CONCLUSION: This qualitative study presents the first national study providing insightful information regarding current undergraduate dental students' decision process in relation to their profession selection, and shows that opportunities to provide patient care seems to be the key to motivation. There was also a strong inclination towards performing hands-on practical tasks as a dentist, and developing a professional status. Interestingly, financial reward did not feature as a motivational factor in this study. The study highlights the influence of socio-cultural and economic factors on choosing dentistry as a career. This data could help dental institutions better understand future applicant's motivations to join dentistry and assist with the academic recruitment/admission process and targeting students with a potential to excel in the profession.

A Phase Inversion-Based Microfluidic Fabrication of Helical Microfibers towards Versatile Artificial Abdominal Skin.

Microfluidic spinning technology (MST), incorporating microfluidics with chemical reactions, has gained considerable interest for constructing anisotropic advanced microfibers, especially helical microfibers. However, these efforts suffer from the limited material choices, restricting their applications. Here, a new phase inversion-based microfluidic spinning (PIMS) method is proposed for producing helical microfibers. This method undergoes a physicochemical phase inversion process, which is capable of efficiently manufacturing strong (tensile stress of more than 25 MPa), stretchable, flexible and biocompatible helical microfibers. The helical microfibers can be used to fabricate bi-oriented stretchable artificial abdominal skin, preventing incisional hernia formation and promoting the wound healing without conglutination. This research not only offers a universal approach to design helical microfibers but also provides a new insight into artificial skin.

The Rapid and Large-Scale Production of Carbon Quantum Dots and their Integration with Polymers.

Carbon quantum dots (CDs) have inspired vast interest because of their excellent photoluminescence (PL) performances and their promising applications in optoelectronic, biomedical, and sensing fields. The development of effective approaches for the large-scale production of CDs may greatly promote the further advancement of their practical applications. In this Minireview, the newly emerging methods for the large-scale production of CDs are summarized, such as microwave, ultrasonic, plasma, magnetic hyperthermia, and microfluidic techniques. The use of the available strategies for constructing CD/polymer composites with intriguing solid-state PL is then described. Particularly, the multiple roles of CDs are emphasized, including as fillers, monomers, and initiators. Moreover, typical applications of CD/polymer composites in light-emitting diodes, fluorescent printing, and biomedicine are outlined. Finally, we discuss current problems and speculate on their future development.

Rapid preparation of auto-healing gels with actuating behaviour.

Gels with multiple stimuli-responsive actuating behaviour have shown great potential in many applications. Nevertheless, facile approaches to rapidly preparing gel actuators are still highly needed, and obtaining gels possessing both actuating and auto-healing capabilities remains a challenge. Herein, we report the rapid preparation of gel actuators with a self-healing ability. Dual-component gels, composed of poly(BA-co-VI-co-AM) (G-1) and poly(BA-co-AA-co-AM/ß-CD) (G-2) (BA = butyl acrylate, VI = N-vinyl imidazole, AM = acrylamide, AA = acrylic acid, ß-CD = ß-cyclodextrin), are prepared within 10 minutes (min) via biphase frontal polymerization (FP). Both G-1 and G-2 gels show excellent intrinsic self-healing properties based on hydrogen bonds, with healing efficiencies of 91% and 97%, respectively; self-healing between G-1 and G-2 also occurs due to hydrogen bonding and host-guest interactions. Moreover, dual-component gels, in terms of G-1 and G-2 bilayer gel flowers and strips, heterogeneous healed bilayer gel strips, and microfluidic-directed bilayer gel microsphere ensembles, all show actuating behaviour in acidic, alkaline and organic solutions, with actuation degrees up to 96% in 5 min. The actuation mechanism is also proposed. This work might provide new insights into fast synthesis of self-healing dual-component gels towards application in the actuator field.

Measuring medical students' professional competencies in a problem-based curriculum: a reliability study.

BACKGROUND: Identification and assessment of professional competencies for medical students is challenging. We have recently developed an instrument for assessing the essential professional competencies for medical students in Problem-Based Learning (PBL) programs by PBL tutors. This study aims to evaluate the reliability and validity of professional competency scores of medical students using this instrument in PBL tutorials. METHODS: Each group of seven to eight students in PBL tutorials (Year 2, n = 46) were assessed independently by two faculty members. Each tutor assessed students in his/her group every five weeks on four occasions. The instrument consists of ten items, which measure three main competency domains: interpersonal, cognitive and professional behavior. Each item is scored using a five-point Likert scale (1 = poor, 5 = exceptional). Reliability of professional competencies scores was calculated using G-theory with raters nested in occasions. Furthermore, criterion-related validity was measured by testing the correlations with students' scores in written examination. RESULTS: The overall generalizability coefficient (G) of the professional competency scores was 0.80. Students' professional competencies scores (universe scores) accounted for 27% of the total variance across all score comparisons. The variance due to occasions accounted for 10%, while the student-occasion interaction was zero. The variance due to raters to occasions represented 8% of the total variance, and the remaining 55% of the variance was due to unexplained sources of error. The highest reliability measured was the interpersonal domain (G = 0.84) and the lowest reliability was the professional behavior domain (G = 0.76). Results from the decision (D) study suggested that an adequate dependability (G = 0.71) can be achieved by using one rater for five occasions. Furthermore, there was a positive correlation between the written examination scores and cognitive competencies scores (r = 0.46, P < 0.01), but not with the other two competency domains (interpersonal and professionalism). CONCLUSIONS: This study demonstrates that professional competency assessment scores of medical students in PBL tutorials have an acceptable reliability. Further studies for validating the instrument are required before using it for summative evaluation of students by PBL tutors.

Supervised practice program guided by the Accreditation Council for Education in Nutrition and Dietetics standards improves potential employability of nutrition/dietetics graduates: perspective of employers and preceptors.

BACKGROUND: This study investigated employers' perspectives on the impact of a supervised practice program (SPP), guided by international accreditation standards on the skill development and potential employability of dietetics students. MAIN BODY: This study was based on qualitative research. Fifteen potential employers, who also served as SPP preceptors, participated in this study. Participants were interviewed using semi-structured questionnaire. All interviews were conducted face-to-face by a trained interviewer. Participates were invited to discuss their own experiences in the current SPP, their perceptions of the impact of SPP on skills and attributes of graduates, and their overall ideas of how SPP may contribute to the employability of graduates. This study found that the SPP program guided by international accreditation standards shaped the duties and responsibilities of preceptors/supervisors and promoted a beneficial relationship between preceptors and SPP students. The benefits to graduates include bridging the gap between classroom didactic knowledge and practice; improving workplace self-confidence; developing competencies such as critical-thinking, communication, interviewing, and counselling skills in various multidisciplinary and multicultural settings. In addition, the preceptors suggested that accreditation-guided SPP contributes to the employability of graduates. Also, they opined that it reduced the need for orientation and shortened the probation time because students were familiar with the work environment and work flow. This lead to the improved preparedness for work. CONCLUSION: SPP based on set of competencies guided by international accreditation standards provides an up-to-date curriculum, improves the quality of the nutrition and dietetics services, and increases the potential employability of the graduates.

Development of professional identity among dental students - A qualitative study.

PURPOSE: The study explored dental students' perception of their professional identity (PI) development at a newly established dental college with a problem-based learning (PBL) curriculum. METHODS: Qualitative methods based on focus groups were used for data collection. The conceptual framework of the study was informed by a subject-centered sociocultural approach to PI development. Purposive sampling was used to collect data from five focus groups of undergraduate dental students to gain a deeper understanding of their PI development in a PBL environment. RESULTS: Out of a total of 38 dental students in years 2 and 3, 34 students (89.47%) participated in the focus groups. A theory-driven thematic analysis was used to dissect the views and experiences of the participants to explore factors contributing to PI development in the early years of the program. At an individual level, PBL was seen to be appropriate for PI development. However, some participants placed more emphasis on practical training in operative dental skills. Relational sources especially role modeling by the PBL facilitators and faculty staff were identified as a key factor to nurture PI development. Mixed views were observed on the value of PBL to enhance team-working skills. The participants also identified challenges of PBL and provided recommendations on further improvements to enhance the learning experiences of the students. CONCLUSIONS: This study provided useful insights into a PBL curriculum at a newly established dental institution. The findings underscore the value of PBL in developing PI and also highlight the challenges of implementing PBL in a socio-cultural context and pedagogical implications for further program improvement.

Exploring the challenges of virtual internships during the COVID-19 pandemic and their potential influence on the professional identity of health professions students: A view from Qatar University.

Introduction: COVID-19 has imposed many shared limitations on medical and health education. Just like other health professions programs at most institutions, the Qatar University health cluster (QU Health) applied a containment approach and shifted all learning online, and onsite training was replaced by virtual internships (VIs) during the first wave of the pandemic. Our study aims to explore the challenges of virtual internships during the COVID-19 pandemic and their influence on the professional identity (PI) of the health cluster students from the College of Medicine, the College of Health Sciences, and the College of Pharmacy at Qatar University. Methods: A qualitative approach was employed. In total, eight focus groups with students (N = 43) and 14 semi-structured interviews with clinical instructors from all the health cluster colleges were conducted. Transcripts were analyzed following the inductive approach. Results: The major challenges reported by students were mainly related to the lack of the required skills for navigating the VI, professional and social stressors, the nature of VIs and the quality of learning, technical and environmental issues, and the development of students' professional identity in an alternative internship environment. The challenges relating to the development of professional identity included: limited clinical (practical) experience, a lack of experience in fighting a pandemic, a lack of communication and feedback, and a lack of confidence in meeting the internship's goals. A model was constructed to represent these findings. Discussion: The findings are important in identifying the inevitable barriers to virtual learning for health professions students and provide a better understanding of how such challenges and different experiences would be affecting the development of their PI. Hence, students, instructors, and policymakers alike should strive to minimize these barriers. Since physical interactions and patient contact are indispensable components of clinical teaching, these extraordinary times demand innovations involving technology and simulation-based teaching. There is a need for more studies that are focused on determining and measuring the short- and long-term effects of the VI on students' PI development.

Health sciences students' and instructors' perceptions of the emergency switch to virtual internship amid the COVID-19 pandemic: A case from Qatar.

In efforts to contain the COVID-19 pandemic, health colleges at Qatar University shifted their clinical training to virtual internships (VI) and project-based learning (PBL). The shift was new to students and faculty alike, and a major change that posed many challenges. This study aimed to explore the experience of changing to VIs during the pandemic from both the clinical instructors' and health sciences students' perspectives. A qualitative study was conducted based on the framework of readiness to change. It involved focus group discussions with students from the departments of Public Health and Human Nutrition and in-depth interviews with clinical instructors using appropriate online platforms. A total of 4 focus groups with 20 students and 4 interviews with instructors were conducted. Transcripts were analyzed following the inductive-deductive approach. The major themes that emerged from the analysis described students' and clinical instructors' perceptions of the necessity and efficiency of the switch to VI; the design of the VI and the extent of the clinical/field experience and skills that it offered; confidence in the ability to succeed in this type of internship and confidence about reaching expected goals; academic and moral support from clinical faculty and coordinators and the communication process with faculty and preceptors; and finally, the benefits gained and how employers would view this type of internship. Health sciences students' readiness for VI was generally low. Several student and faculty needs have to be addressed, specifically regarding the design of the program and the level of preceptors' communication with students. The findings would direct health programs, clinical instructors, and preceptors to better understand students' needs and efficiently plan for virtual internships during not only emergencies but also whenever there is a need to deliver online experiential learning courses.

Microfluidic spinning-induced heterotypic bead-on-string fibers for dual-cargo release and wound healing.

The preparation of dual-release pharmaceutical microfibers provides an ideal material for new biomedical applications. We describe a microfluidic spinning method for engineering heterotypic bead-on-string fibers with the ability to carry dual cargos and to deliver on demand. The core of our technology is to combine microfluidic spinning with biomaterial preparation, in which hydrophobic and hydrophilic cargos can be integrated into a bead-on-string microfiber structure. We demonstrate the loading of bovine serum albumin (BSA) in the sodium alginate phase and ibuprofen in the polylactic acid (PLA) phase, respectively. The heterotypic bead-on-string fibers are biocompatible and show hemostatic ability in vivo. These heterotypic bead-on-string fibers are then woven as a skin scaffold and shown to promote wound healing by loading antibacterial and anti-inflammatory cargos.

Macroscopic Self-Assembly of Gel-Based Microfibers toward Functional Nonwoven Fabrics.

Macroscopic self-assembly has increasingly attracted numerous concerns because of the facile fabrication of complex structures and diversified morphologies. Key challenges still remain to design high-performance building blocks to increase the efficiency and diversity of macroscopic self-assembly. Here, we designed triple noncovalent interactions (carboxyl-Zn2+ coordination, host-guest interactions, and hydrogen bonding interactions) to enhance the interactions between self-healing fibers, constructing multidimensional nonwoven fiber-based fabrics through macroscopic self-assembly without further postprocessing. Profiled from the strong interactions generated from triple noncovalent interactions, ordered two-dimensional plane and three-dimensional spiral gel fabrics were fabricated using polyvinyl pyrrolidone/gel-based fibers as building blocks toward a human motion sensor. Moreover, we demonstrated that the macroscopic self-assembly strategy is universal to construct three-dimensional film-based fabrics toward wound dressing based on the triple noncovalent interactions between two-dimensional films. This macroscopic self-assembly approach provides an alternative strategy to fabricate gel fabrics for various applications.

Multifunctional Micro/Nanoscale Fibers Based on Microfluidic Spinning Technology.

Superfine multifunctional micro/nanoscale fibrous materials with high surface area and ordered structure have attracted intensive attention for widespread applications in recent years. Microfluidic spinning technology (MST) has emerged as a powerful and versatile platform because of its various advantages such as high surface-area-to-volume ratio, effective heat transfer, and enhanced reaction rate. The resultant well-defined micro/nanoscale fibers exhibit controllable compositions, advanced structures, and new physical/chemical properties. The latest developments and achievements in microfluidic spun fiber materials are summarized in terms of the underlying preparation principles, geometric configurations, and functionalization. Variously architected structures and shapes by MST, including cylindrical, grooved, flat, anisotropic, hollow, core-shell, Janus, heterogeneous, helical, and knotted fibers, are emphasized. In particular, fiber-spinning chemistry in MST for achieving functionalization of fiber materials by in situ chemical reactions inside fibers is introduced. Additionally, the applications of the fabricated functional fibers are highlighted in sensors, microactuators, photoelectric devices, flexible electronics, tissue engineering, drug delivery, and water collection. Finally, recent progress, challenges, and future perspectives are discussed.

Host-guest supramolecular assembly directing beta-cyclodextrin based nanocrystals towards their robust performances.

Fluorescent CdTe nanocrystals (NCs) capped with beta-cyclodextrin (ß-CD) are successfully synthesized by host-guest supramolecular assembly of the hydrophobic alkyl chains of N-acetyl-l-cysteine (NAC) on the surface of CdTe NCs and eco-friendly ß-CD via the promising simple hydrothermal method in our experiments. The as-prepared NCs display better stability and lower toxicity compared with traditional those only capped with NAC. Specially, cytotoxicity experiments to human umbilical vein endothelial cells in vitro and zebrafish embryo toxicological tests in vivo are performed to determine the toxicity of CdTe NCs. For their practical applications, the promising red-luminescent NCs are employed as stable and low poison red phosphors to fabricate white light-emitting diodes (WLEDs) with remarkable color-rendering index (CRI) being 91.6. This research offers significance for solving the difficulty in toxicity and instability of heavy metal based NCs, which has potential applications in future optoelectronic devices and biomarkers.