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Abstract Background Computational thinking (CT) is crucial to fostering critical thinking and problem-solving skills. Many elementary schools have been cultivating students’ CT through block-based programming languages such as Scratch using traditional teacher-centered teaching methods. However, the approach excessively relies on teacher lectures, so the teacher’s teaching load is hefty, and most students cannot receive timely assistance from teachers, thus reducing students’ programming learning performance, interest, and confidence. Therefore, this study designs a Jigsaw collaborative learning method implemented in a metaverse virtual space (JCLM-MVS) for peer-to-peer Scratch programming learning to promote learners’ programming learning performance, CT, and learning attitudes. This study used a quasi-experimental research method, with 48 fifth-grade students from two classes in Taiwan’s elementary school as the research participants. One class of 24 students was randomly assigned to the experimental group using JCLM-MVS to conduct Scratch programming learning, whereas the other class of 24 students was assigned to the control group using the traditional teacher-centered teaching method. Main findings The study found that the experimental group of learners showed significantly better Scratch programming learning performance and attitude than the control group, and there was no statistically significant difference in CT between both groups, but both learning approaches effectively promoted CT. Additionally, the interview results showed that most interviewees stated that using JCLM-MVS for Scratch programming learning could receive timely assistance from peers, make collaborative learning more efficient and learning more enjoyable, and more intend to use JCLM-MVS for Scratch programming learning than using traditional teacher-centered teaching method due to the effective collaborative interaction mechanisms and realistic learning space provided in the metaverse virtual space. Conclusions/potential implications This study presents a novel and engaging learning approach by integrating a metaverse virtual space with the Jigsaw collaborative learning method, referred to as JCLM-MVS, which enhances the effectiveness of the Jigsaw collaborative learning method in promoting Scratch programming learning performance, CT, and attitudes.

The microstructure and uniformity of Cu metallization in the through glass via (TGV) structure were investigated through electron backscatter diffraction (EBSD) analysis system and finite element analysis (FEA) method. Two different direct current (DC) electroplating methods were employed for the TGV metallization, including single- and multiple-step electroplating methods. We found that the multiple-step electroplating process with appropriate current density (j)/plating time (t) can efficiently enhance the throwing power (TP) value (uniformity) of electroplated Cu in the TGV metallization. Moreover, the Cu electrodeposition via the multiple-step electroplating process possessed larger grain sizes and high fraction of high angle grain boundaries (HAGBs), including twin boundaries (TBs), which are very beneficial to the mechanical and electrical properties of Cu interconnects. Detailed analyses of the uniformity (i.e., TP), crystallographic microstructure (e.g., grain size), and mechanical characteristics (e.g., ductility) of electroplated Cu derived from single- and multiple-step electroplating process were discussed in this paper.

Leishmania is a parasitic protozoan belonging to the family Trypanosomatidae. Leishmaniasis, caused by infection with Leishmania parasites, can manifest in three primary forms: cutaneous, mucocutaneous, and visceral. Approximately 2 million individuals worldwide are affected by leishmaniasis, with an estimated 0.7–1 million new cases occurring annually and around 20,000–65,000 deaths reported annually. Current chemotherapy for leishmaniasis faces several challenges, including high costs, adverse effects, drug resistance, and disease relapse. Consequently, there is an urgent need for alternative treatments. Drug repurposing presents a promising strategy for discovering and developing new antileishmanial therapeutics. This review aims to explore and summarize recent advances in the identification of antileishmanial drugs, highlighting the successful repurposing of existing drugs for leishmaniasis and their transition from academic research to industrial application. These advancements are primarily based on integrated computational and experimental approaches, including in silico, in vitro, and in vivo screening, as well as biological and biochemical analyses to identify effective antileishmanial agents. Further studies are needed to elucidate the mechanisms of action of these new leads and to conduct preclinical and clinical evaluations of the identified drugs for potential antileishmanial therapy.

Self-assembled monolayers (SAMs) with short organic chains terminated with specific functional groups are attractive for modifying surface properties for a variety of applications, including being a copper diffusion barrier layer on Si wafer. However, SAM formation is process-sensitive and ideal SAM is difficult to obtain, both of which need to carefully deal with before practical use. Herein we developed a system to achieve seamless electroless deposited copper (ELD Cu) film on an amino-terminated silane SAM modified Si wafer with the help of a bifunctional polyvinyl alcohol-capped Pd nanocluster (PVA-Pd) catalyst. The PVA-Pd acts as a catalyst for ELD Cu as well as a healing agent to fix defects of the amino silane SAM. The sheet resistance, cross-sectional morphology analysis and adhesion of ELD Cu on the Si wafer are extensively studied. By controlling the abundancy of PVA in PVA-Pd, the diffusion barrier property of a flawed amino-terminated silane SAM remains reliably effective even after a 500 °C rapid thermal annealing (RTA), evidencing the superior healing function of PVA. The whole thickness of the PVA-Pd/amino-terminated silane SAM before and after RTA is 〜6 nm and 〜2 nm, respectively, which is applicable for advanced microelectronic manufacturing.

Sn-3Ag-0.5Cu (SAC305)- and Sn-9Zn-based alloys (Sn-Zn-X, X = Al, In) are lead-free solders used in the fabrication of solder joints with Cu metallization. Electroplating is a facile technology used to fabricate Cu metallization. However, the addition of functional additive molecules in the plating solution may result in impurity residues in the Cu electroplated layer, causing damage to the solder joints. This study investigates the impurity effect on solder joints constructed by joining various solder alloys to the Cu electroplated layers. Functional additives are formulated to fabricate high-impurity and low-impurity Cu electroplated samples. The as-joined solder joint samples are thermally aged at 120 °C and 170 °C to explore the interfacial reactions between solder alloys and Cu. The results show that the impurity effect on the interfacial reactions between SAC305 and Cu is significant. Voids are massively formed at the SAC305/Cu interface incorporated with a high impurity content, and the Cu6Sn5 intermetallic compound (IMC) grows at a faster rate. In contrast, the growth of the Cu5Zn8 IMC formed in the SnZn-based solder joints is not significantly influenced by the impurity content in the Cu electroplated layers. Voids are not observed in the SnZn-based solder joints regardless of the impurity content, indicative of an insignificant impurity effect. The discrepancy of the impurity effect is rationalized by the differences in the IMC formation and associated atomic interdiffusion in the SAC305- and SnZn-based solder joints.

This work investigates a two-way communication retrial queue with synchronous working vacation and a constant retrial policy. During the idle time, a server makes an outgoing call after a random length. The service time of the incoming call and outgoing call obeys exponential distribution with different rates. If the incoming call finds all servers to be unavailable, it may or may not enter orbit. All servers immediately go on vacation simultaneously as soon as they find an empty system after the service finishes. During vacation, the servers can provide a service to those incoming calls, but this is at a lower-speed rate. The stationary probability distribution and the ergodic condition are obtained utilizing the matrix geometric technique. Some system characteristics are developed. Using MATLAB software, the variation in average orbit length, idle ratio, and the average number of servers in different server states is plotted for different values of the incoming/outgoing call rate and retrial rate. We further propose a multi-objective optimization model from which the optimal rate of outgoing calls and optimal vacation rate are explicitly obtained.

It is difficult for students to learn the concepts of chemical laboratory safety education from actual experiences because the traditional teaching model prohibits students from performing dangerous operations. Therefore, this study develops a novel mixed reality-based chemistry experiment learning system (MRCELS) to allow learners to conduct inquiry-based experimental operations in an environment integrating virtual and physical space by using a free and safe way so that chemical laboratory safety problems that usually occur in actual chemical laboratories that may hurt learners can be avoided. A total of 36 Grade 11 students from a girl's high school in Taipei City, Taiwan, were recruited to participate in the experiment. A total of 17 students were randomly assigned to the experimental group using the MRCELS to conduct chemical laboratory safety education, while the remaining 19 students were randomly assigned to the control group taught by a teacher in a physical-chemical laboratory. The research results show that the learning effectiveness of experimental group learners in chemical laboratory safety education is significantly superior to that of the control group. Besides, experimental and control groups significantly improved their attitudes toward laboratory safety after the instruction experiment, but no significant differences existed between them. Both groups of learners showed high satisfaction with the learning model they used, but no significant differences existed between them. Encouragingly, according to the interview results, learners preferred to adopt the MRCELS to support learning. They stated that the immersion experience in operating the chemical experiments through the MRCELS could enhance their awareness of hazardous operations and the development of laboratory safety concepts. The developed MRCELS contributes an effective and innovative learning model to chemical laboratory safety education.

This study utilised the instant semantic analysis and feedback system (ISAFS) to assist learners in the online discussion learning activities of socio-scientific issues (SSIs) and to document their learning process behaviours for behavioural analyses. The aim was to understand the learners' discussion behaviours during the ISAFS assisted learning process and to guide them in exhibiting more effective discussion behaviours in order to facilitate the learning effectiveness of online asynchronous discussions. The research participants were 55 eleventh-grade students from a senior high school in northeastern Taiwan. A single pre-experimental group design was adopted to collect the learning process data. Eventually, 34 effective samples were considered following the online discussions. The results showed that learners with distinct computer-mediated communication competences and personality traits have different behaviour patterns. Overall, the behavioural analyses reveal that different learning behaviours would result in distinct learning effectiveness, and that learners with different computer-mediated communication competences and personality traits would present various learning behaviours. Based on the research results, suggestions for the application of ISAFS in teaching and implications for future developments are proposed. The findings could be instrumental in the improvement of the teaching process through online discussions.

The manufacturing process for corrugated paper products is usually mass production and batch-by-batch production. Therefore, a high-speed mass production is required. Because the conveyer speed of the production line in a corrugated paper plant is very fast, unwanted material loss or even process interruption may occur during the cutting or clipping process if the corrugated paper on the conveyer is slanted. Hence, the paper alignment on a conveyer is important and necessary. In this study, we install photo-couples at both edges directly over the conveyer path to detect whether or not the corrugated paper is slanted from the number difference between non-activated photo-couples of the two edges. The deviated angle is calculated through a computer program using the detected information, and a servomotor-driven wheel aligns the paper in accordance with the calculated angle. This work reduces the material waste and promotes the production reliability and utility rate of the material for a corrugated paper plant. [ABSTRACT FROM AUTHOR]

Bearings are common components used in the transmission system of tool machinery and linear drive equipment. With increasing demand for higher efficiency and faster production under the required accuracy, the control of bearing temperature rise under high operational speed becomes a critical issue. The improper control of temperature rise can lead to the thermal deformation and life reduction of the machinery. Conventionally, a circulating oil lubrication system is utilized with journal bearings. In this study, a similar lubrication system was adopted for the ball bearing with a retrofit design. Three control factors, i.e., rotational speed, bearing preload, and the viscosity of the lubricant used, were chosen to study their effects on the temperature performance of the proposed lubrication system. Experimental measurements showed that the lubrication system was able to lower the temperature rise of the bearing considerably compared with its unlubricated counterpart, especially at high rotational speeds. Even with the enhanced cooling from the oil circulation system, temperature rise still increased with rotational speed. However, with increased preload, the temperature rise first dropped and then increased owing to the different contact characteristics of the balls and rings of the bearing. A fitted function for the temperature rise of the bearing under different operational conditions was demonstrated to have a prediction accuracy within 3%. Therefore, the retrofitted bearing oil cooling system should be applicable in the design of high-speed machinery for industry. [ABSTRACT FROM AUTHOR]

Abstract Aims Research evidence has established an association of obsessive-compulsive disorder (OCD) with suicidal thoughts and suicide attempts. However, further investigation is required to determine whether individuals with OCD have higher risk of death by suicide compared with those without OCD. Methods Of the entire Taiwanese population, between 2003 and 2017, 56,977 individuals with OCD were identified; they were then matched at a 1:4 ratio with 227,908 non-OCD individuals on the basis of their birth year and sex. Suicide mortality was assessed between 2003 and 2017 for both groups. Time-dependent Cox regression models were used to investigate the difference in suicide risk between individuals with versus without OCD. Results After adjustment for major psychiatric comorbidities (i.e., schizophrenia, bipolar disorder and major depressive disorder), the OCD group had higher risk of suicide (hazard ratio: 1.97, 95% confidence interval: 1.57–2.48) during the follow-up compared with the comparison group. Furthermore, OCD severity, as indicated by psychiatric hospitalizations due to OCD, was positively correlated with suicide risk. Conclusions Regardless of the existence of major psychiatric comorbidities, OCD was found to be an independent risk factor for death by suicide. A suicide prevention program specific to individuals with OCD may be developed in clinical practice in the future.

Probiotics and prebiotics have gained attention for their potential health benefits. However, their efficacy hinges on probiotic survival through the harsh gastrointestinal environment. Microencapsulation techniques provide a solution, with resistant starch (RS)-based techniques showing promise in maintaining probiotic viability. Specifically, RS-encapsulated probiotics significantly improved probiotic survival in gastric acid, bile salts, and simulated intestinal conditions. This study investigated the effects of a resistant-starch-encapsulated probiotic cocktail (RS-Pro) in the context of 5-fluorouracil (5-FU) chemotherapy, which frequently induces microbiota dysbiosis and intestinal mucositis. Female BALB/c mice were divided into three groups: a 5-FU group, a 5-FU+Pro group receiving free probiotics, and a 5-FU+RS-Pro group receiving RS-encapsulated probiotics. After 28 days of treatment, analyses were conducted on fecal microbiota, intestinal histology, peripheral blood cell counts, and body and organ weights. It was revealed by 16S rRNA MiSeq sequencing that 5-FU treatment disrupted gut microbiota composition, reduced microbial diversity, and caused dysbiosis. RS-Pro treatment restored microbial diversity and increased the population of beneficial bacteria, such as Muribaculaceae, which play roles in carbohydrate and polyphenol metabolism. Furthermore, 5-FU administration induced moderate intestinal mucositis, characterized by reduced cellularity and shortened villi. However, RS-Pro treatment attenuated 5-FU-induced intestinal damage, preserving villus length. Mild leukopenia observed in the 5-FU-treated mice was partially alleviated in 5-FU+Pro and 5-FU+RS-Pro groups. These findings suggest that RS-Pro may serve as an adjunct to chemotherapy, potentially reducing adverse effects and improving therapeutic outcomes in future clinical applications.

5-Fluorouracil (5-FU) is commonly used as the primary chemotherapy for colorectal cancer (CRC). However, it can lead to unwanted chemoresistance. Resistant starch (RS), which functions similarly to fermentable dietary fiber, has the potential to reduce the risk of CRC. The effects of RS on improving CRC-associated cachectic symptoms and 5-FU chemotherapy-induced microbial dysbiosis remain unknown. Female BALB/cByJNarl mice were randomly divided into four groups: one tumor group (with CT26 colonic carcinoma but no treatment) and three CT26 colonic carcinoma-bearing groups that were administered 20 mg/kg 5-FU (T+5-FU group), a probiotic cocktail (4 × 108 CFUs) plus chemotherapy (T+5-FU+Pro), or resistant-starch-encapsulated probiotics plus chemotherapy (T+5-FU+RS-Pro). T+5-FU and T+5-FU+RS-Pro administration significantly suppressed tumor growth and activated apoptotic cell death in CT26-bearing mice. 5-FU-induced increases in inflammatory cytokines and NF-κB signaling were mitigated by the Pro or RS-Pro supplementation. A gut microbial composition comparison indicated that the abundance of intestinal bacteria in the T and T+5-FU groups decreased significantly, while the groups receiving Pro or RS-Pro maintained a greater abundance and healthy gut microbiota composition, suggesting that RS can reduce the microbial dysbiosis that occurs during 5-FU chemotherapy. The use of RS-Pro before chemotherapy should be considered for the regulation of chemotherapy-associated cachectic symptoms, inflammation, and chemotherapy-induced microbial dysbiosis.