Search

This research identifies the critical factors of student engagement and distance learning that will improve academic performance during a pandemic. The fuzzy Delphi method and fuzzy analytical hierarchy process method are applied to this research, which is a multicriteria decision-making technique. A survey is conducted and evaluated based on experts' opinions. The social constructivism theory was selected to be applied here; it supports student engagement and distance-learning factors' relationships with academic performance. After the analysis, the six most significant factors are evaluated. It is observed that Social isolation (C1), Technology effectiveness (C2), Social status enhancement (C3), Student Competency (C4), Motivation (C5), and Satisfaction (C6) are the highest-ranking factors that increase academic performance. On the basis of the results, it is suggested that management's primary responsibility is to provide training and guidance to instructors/teachers to enhance, motivate the students, and create opportunities for every student to improve their academic performance in a pandemic situation through distance learning.

Single-crystalline transition metal dichalcogenides (TMD) films are of potential application in future electronics and optoelectronics. In this work, a halide vapor phase epitaxy (HVPE) strategy was proposed and demonstrated for the epitaxy of molybdenum diselenide (MoSe2) single crystals, in which metal halide vapors were in-situ produced by the chlorination of molybdenum as sources for the TMD growth. Combined with the epitaxial sapphire substrate, unidirectional domain alignment was successfully achieved and monolayer single-crystal MoSe2 films have been demonstrated on a 2-inch wafer for the first time. A series of characterizations ranging from centimeter to nanometer scales have been implemented to demonstrate the high quality and uniformity of the MoSe2. This work provides a universal strategy for the growth of TMD single-crystal films.

Objectives: This study evaluated the expression and significance of SNHG3 in rheumatoid arthritis (RA), aiming to explore a biomarker and regulator for RA. Methods: The expression of SNHG3 in serum and synovial tissue was compared between RA patients and healthy individuals using polymerase chain reaction (PCR). The RA animal models were induced by the Porcine Type II collagen in Wistar rats and validated by the foot volume and arthritis index score. The human fibroblast-like synoviocytes were treated with lipopolysaccharide (LPS) to mimic the injury during RA onset, and the cell growth was assessed by cell counting kit-8 (CCK8) assay. Results: SNHG3 was significantly downregulated in the serum and synovial tissue of RA patients compared with healthy individuals. Downregulated SNHG3 could discriminate RA patients from healthy individuals with high sensitivity (0.875) and specificity (0.844). Porcine Type II collagen induced increasing foot volume and arthritis index scores of rats, and SNHG3 was downregulated in RA rats. In LPS-induced human fibroblast-like synoviocytes, SNHG3 negatively regulated miR-128-3p, and the alleviated effect of SNHG3 overexpression on cellular inflammation and oxidative stress was reversed by miR-128-3p upregulation. Conclusions: Serum SNHG3 was considered a potential diagnostic biomarker for RA from healthy individuals. SNHG3 regulated inflammatory response and oxidative stress by negatively modulating miR-128-3p. [ABSTRACT FROM AUTHOR]

Nanomaterial phonon transport is crucial for miniaturized devices and superior thermophysical properties in condensed matter physics. Diamond nanosheets, applicable in nanoelectronics/optoelectronics, offer availability to explore dimensionality's impact on phonon transport. Raman spectroscopy is used to study the thermal conductivity (κ) of diamond nanosheets with a thickness below 100 nm. Results show a κ∼T−1$\kappa \sim {{T}^{ - 1}}$ law above 140 K, highlighting Umklapp phonon scattering. Despite the reduced thickness, κ (1100‐2000 W/mK) remains higher than metals and most semiconductors, showcasing diamonds' remarkable in‐plane heat transfer. Intriguingly, the research uncovers unique length‐dependent behavior κ∼log(L)$\kappa \sim {\mathrm{log}}(L)$, consistent with graphene, the two‐dimensional (2D) allotrope. This research offers insights into thermal transport in quasi‐2D nanosheets, with significant implications for nanoscale heat management and highly efficient thermal devices. [ABSTRACT FROM AUTHOR]

This study presents a rapid synthesis method using carbon fibers, converting ammonium tetrathiomolybdate to molybdenum disulfide films with controllable thickness (1–5 nm) and smooth surface (200 pm on average) in tens of seconds. Electronic devices based on these multilayers exhibit promising performance: memristors operate at an average of 1.5 V; field-effect transistors display electron mobility ranging from 0.1 to 0.4 cm2/V·s with a 103 on/off ratio. The electrical performance can be enhanced by optimizing annealing recipes. This scalable, time-efficient method holds the potential for large-scale production of multilayer two-dimensional semiconductors for electronics. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2) is an emerging class of new materials with a wide range of potential practical applications. However, the uncontrollability of monolayer MoS2 synthesized by traditional chemical vapor deposition method and the low responsivity of MoS2 photodetectors limit its further development in the field of photoelectric detection. To achieve controlled growth of monolayer MoS2 and construct MoS2 photodetectors with a high responsivity, we propose a novel single crystal growth strategy of high-quality MoS2 by controlling the Mo to S vapor ratio near the substrate, and deposit a layer of hafnium oxide (HfO2) on the surface of MoS2 to enhance the performance of the pristine metal-semiconductor-metal structure photodetector. At a reverse bias of 8 V, the HfO2 passivated MoS2 photodetector features an extremely high responsivity of 1201 AW − 1 , a response time of around 0.5 s, and a detectivity of 7.7 × 10 11 Jones. Meanwhile, we deeply investigate the effect of the HfO2 layer on the performance of the fabricated MoS2 photodetector and propose a physical mechanism to interpret the obtained experiment results. These results might facilitate a better understanding on the performance modulation of the MoS2 photodetectors and accelerate the development of MoS2-based optoelectronic devices. [ABSTRACT FROM AUTHOR]