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Background: Given the advancement of mobile and sensing technology, the incorporation of augmented reality (AR) in context-aware ubiquitous learning (CAUL) has offered significant benefits to oral communication development in foreign language learning. Although a great number of studies have been dedicated in this field, only a little research was conducted to formulate a facilitation framework aligning with established learning theories or pedagogies. Objectives: This review thereby examined the facilitation tenets conducive to the best practice of AR-based CAUL projects for oral communication enhancement and further established a AR-guided CAUL framework. Methods: The researchers systematically reviewed 17 related empirical AR studies from Web of Science from 2000 to 2021 and synthesized the results with focused second language acquisition theories. Results and Conclusions: Three practical tenets were identified, including facilitating learner-centred pedagogies with personal and contextual learning supports, incorporating constructivist learning design, and encouraging collaborative learning and higher-order cognitive skills. Furthermore, in accordance with the synthesized results, a facilitation framework combining situated learning, learning-by-doing, and social constructivist design was developed to engage students in a learning, applying, and reflecting process in formal and informal learning contexts. Major Takeaways: For the best practice of oral communication through AR, this review study offers practical facilitation tenets and theoretical framework which are in alignment with research-proven theories. It is expected that the framework could provide frontline educational practitioners with guidance to foster students' learning outcomes and interactions.

With the advancement of mobile technology, mobile-assisted language learning (MALL) has significant potential regarding its practical applications and benefits in foreign language learning. Nevertheless, little research was conducted to examine factors regarding the facilitation of oral communication through MALL based on established theories or models. The purpose of this review is to investigate the main constituents conducive to the intended outcomes based on an adapted model from Beatty (2010) and further provide guidelines for enthusiastic stakeholders in the field. Twenty-eight empirical studies were collected and categorized according to four key variables of the design model and analyzed qualitatively, with the key findings identified as follows. Due to the technical affordance of mobile technology, it is found that a student-centered self-regulated learning context is created, where students construct knowledge through self-instruction, self-evaluation, and self-correction. Furthermore, a speaking strategy-driven collaborative-based learning design enhances students' oral proficiency through strong social connections, interactions, and communication. Finally, given the pedagogical design and practices, high-level cognitive thinking is thereby promoted, with promising affective learning outcomes. In light of the findings, guidelines for educational practitioners, learners, and system designers are provided for pedagogical and practical application in the future.

Commercialization of photoelectrochemical (PEC) water-splitting technology is hindered by the slower kinetics of oxygen evolution in the currently available photoanodes. Light absorption, charge-separation, and charge-transfer efficiencies determine the kinetics of the oxygen evolution reaction (OER) at semiconductor photoanode surfaces. All these parameters can be maximized by nanotexturing the photoanode surface through morphological (cones, pyramids, grids, etc.) control and crystallographic (facets) orientation. The primary objective of texturing on conducting substrates is to improve the photoconversion efficiency in PEC devices through an increased surface area and light absorption. Laser-assisted ablation and melt-fusion additive techniques allow for rapid iteration of morphological architecture designs for optimized light absorption properties. This work reviews various ultrafast laser techniques employed for fabricating nanotextured surfaces and their impact on PEC performance. Compared with conventional electrode fabrication techniques, laser-based surface nanotexturing techniques provide a cost-effective, rapid design, and validation method for the research and development of photoelectrochemical water splitting technologies. [ABSTRACT FROM AUTHOR]

Material shaping and joining are the two fundamental processes that lie at the core of many forms of metal manufacturing techniques, including additive manufacturing. Current metal additive manufacturing processes such as laser/e-beam powder bed fusion and Directed Energy Deposition predominantly use heat and subsequent melt–fusion and solidification to achieve shaping and joining. The energy efficiency of these processes is severely limited due to energy conversion losses before energy is delivered at the point of melt–fusion for shaping and joining, and due to losses through heat transfer to the surrounding environment. This manuscript demonstrates that by using the physical phenomenon of lowered yield stress of metals and enhanced diffusion in the presence of low amplitude high frequency oscillatory strain, metal shaping and joining can be performed in an energy-efficient way. The two performed simultaneously enable a metal additive manufacturing process, namely Resonance-Assisted Deposition (RAD), that has several unique capabilities, like the ability to print net-shape components from hard-to-weld alloys like Al6061 and the ability to print components with a very high aspect ratio. In this study, we show this process's capabilities by printing solid components using aluminum-based metal alloys. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have emerged as a promising class of biomarkers for early detection of various cancers, including ovarian cancer. However, quantifying miRNAs in human blood samples is challenging owing to the issues of sensitivity and specificity. In this study, hsa-miR-200a-3p of the miR-200a sub-family, which is a biomarker of ovarian cancer, was used as the analyte to demonstrate the analytical capability of an integrated biosensing platform using an extremely sensitive surface-enhanced Raman scattering (SERS) nanotag−nanoaggregate-embedded beads (NAEBs), magnetic nanoparticles (MNPs), a pair of highly specific locked nucleic acid (LNA) probes, and a semi-automated paper-based electrowetting-on-dielectric (pEWOD) device to provide labor-less and thorough sample cleanup and recovery. A sandwich approach where NAEBs are modified by one LNA-1 probe and MNPs are modified by another LNA-2 probe was applied. Then, the target analyte miRNA-200a-3p was introduced to form a sandwich nanocomplex through hybridization with the pair of LNA probes. The pEWOD device was used to achieve short cleanup time and good recovery of the nanocomplex, bringing the total analysis time to less than 30 min. The detection limit of this approach can reach 0.26 fM through SERS detection. The versatility of this method without the need for RNA extraction from clinical samples is expected to have good potential in detecting other miRNAs. [ABSTRACT FROM AUTHOR]

A pregnancy booster dose significantly reduces the risk and severity of COVID-19, and it is widely recommended. A prospective cohort study was conducted to compare the transplacental passage of maternal antibodies from vaccination or infection during three trimesters against both the vaccine-targeted Wuhan strain and the Omicron strain of SARS-CoV-2. Maternal–infant dyads from vaccinated mothers were collected between 6 June 2022 and 20 September 2022. We analyzed 38 maternal–infant dyads from mothers who had been infected with COVID-19 and 37 from mothers without any previous infection. Pregnant women who received their last COVID-19 vaccine dose in the third trimester exhibited the highest anti-spike protein antibody levels and neutralizing potency against both the Wuhan strain and Omicron BA.2 variant in their maternal and cord plasma. Both second- and third-trimester vaccination could lead to a higher level of neutralization against the Wuhan and Omicron strains. COVID-19 infection had a negative effect on the transplacental transfer ratio of SARS-CoV-2 antibodies. A booster dose during the second or third trimester is encouraged for the maximum transplacental transfer of humoral protection against COVID-19 for infants. [ABSTRACT FROM AUTHOR]

Preeclampsia (PE) remains one of the leading causes of maternal and perinatal morbidity and mortality. However, the exact pathophysiology of PE is still unclear. The recent widely accepted notion that successful pregnancy relies on maternal immunological adaptation is of utmost importance. Moreover, salt-inducible kinase 3 (SIK3) is an AMP-activated protein kinase-related kinase, and it has reported a novel regulator of energy and inflammation, and its expression related with some diseases. To explore whether SIK3 expression correlated with PE, we analyzed SIK3 gene expression and its association with PE through GEO datasets. We identified that SIK3 was significantly downregulated in PE across four datasets (p < 0.05), suggesting that SIK3 participated in the pathogenesis of PE. We initially demonstrated the significant downregulation of SIK3 in trophoblast cells of PE. SIK3 downregulation was positively correlated with the increased number of CD204(+) cells in in vivo and in vitro experiments. The increased number of CD204(+) cells could inhibit the migration and invasion of trophoblast cells. We then clarified the potential mechanism of PE with SIK3 downregulation: M2 skewing was triggered by trophoblast cells derived via the CCL24/CCR3 axis, leading to an increase in CD204(+) cells, a decrease in phagocytosis, and the production of IL-10 at the maternal–fetal interface of the placenta with PE. IL-10 further contributed to a reduction in the migration and invasion of trophoblast cells. It also established a feedback loop wherein trophoblast cells increased CCL24 production to maintain M2 dominance in the placental environments of PE. [ABSTRACT FROM AUTHOR]

Extrusion-based polymer 3D printing induces shear strains within the material, influencing its rheological and mechanical properties. In materials like polyvinylidene difluoride (PVDF), these strains stretch polymer chains, leading to increased crystallinity and improved piezoelectric properties. This study demonstrates a 400% enhancement in the piezoelectric property of extrusion-printed PVDF by introducing additional shear strains during the printing process. The continuous torsional shear strains, imposed via a rotating extrusion nozzle, results in additional crystalline β-phases, directly impacting the piezoelectric behavior of the printed parts. The effect of the nozzle's rotational speed on the amount of β-phase formation is characterized using FTIR. This research introduces a new direction in the development of polymer and composite 3D printing, where in-process shear strains are used to control the alignment of polymer chains and/or in-fill phases and the overall properties of printed parts. [ABSTRACT FROM AUTHOR]

With the advancement of mobile technology, mobile-assisted language learning (MALL) has significant potential regarding its practical applications and benefits in foreign language learning. Nevertheless, little research was conducted to examine factors regarding the facilitation of oral communication through MALL based on established theories or models. The purpose of this review is to investigate the main constituents conducive to the intended outcomes based on an adapted model from Beatty (2010) and further provide guidelines for enthusiastic stakeholders in the field. Twenty-eight empirical studies were collected and categorized according to four key variables of the design model and analyzed qualitatively, with the key findings identified as follows. Due to the technical affordance of mobile technology, it is found that a student-centered self-regulated learning context is created, where students construct knowledge through self-instruction, self-evaluation, and self-correction. Furthermore, a speaking strategy-driven collaborative-based learning design enhances students' oral proficiency through strong social connections, interactions, and communication. Finally, given the pedagogical design and practices, high-level cognitive thinking is thereby promoted, with promising affective learning outcomes. In light of the findings, guidelines for educational practitioners, learners, and system designers are provided for pedagogical and practical application in the future. [ABSTRACT FROM AUTHOR]