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This exploratory study compares how young people (ages 15-16) learn circuitry concepts and layout design principles important to electrical engineering using one of two educational circuitry toolkits: paper circuits and traditional solderless breadboards. Paper-based prototyping kits are representative of a trend that incorporates new materials and approaches to integrating arts into traditional STEM disciplines. Extending prior research on how non-traditional toolkits enhance learning of electrical engineering outcomes, including basic circuitry concepts (i.e., current flow, polarity, and connections), this study examines the material affordances and design choices of the kits that contribute to youth's understanding of more advanced circuitry layout design principles, including space allocation, placement of electronic components, and routing. Results indicate that paper circuits better afford the learning of layout design principles for printed circuit boards (PCBs) with large effect sizes. This study illuminates how the materials of educational toolkits uniquely solicit body- and material-syntonic patterns of activity, and thus differentially engage learners' powerful ideas around circuitry and design principles. This investigation encourages careful consideration of the material affordances of some toolkits over others for learning purposes.

Industrial process heat decarbonization through electrification could contribute significantly to climate change mitigation efforts. In the US industry, thermal processes accounted for more than two-thirds of the total final energy demand in 2021. Cross-cutting electrification technologies like industrial heat pumps are suitable for the process heat supply to several industrial unit operations in a sustainable way while also improving overall energy efficiency. This study employs a bottom-up approach to investigate the techno-enviro-economic potentials of deploying high-temperature and steam-generating heat pumps in US textile, pulp and paper, and automotive sectors in different timeframes. The results show that the annual technical potential energy and CO2 savings by electrifying heat supply are 310 PJ (or 36% of the projected energy demand) and 28 MtCO2 (or 71% of the projected CO2 emissions) in 2050 respectively, however, these incur additional costs in each sector (ranging between 5 and 18 $/GJ). The required heating capacity of industrial heat pumps is estimated at 15 GW, which translates roughly into a market of over 6000 heat pump units and an investment volume of $7 billion in the studied processes. Although there may be individual cost-effective opportunities for electrifying heat supply in specific industrial sites, the overall costs are estimated to be high in the three industrial sectors due to the large disparity between electricity and natural gas prices and low heat source temperatures. To overcome the identified techno-economic barriers, comprehensive action plans for different stakeholders are also given. This study provides novel insights that should inform policymakers’ and executives’ decisions about the electrification of the current and future US industrial heat supply in relevant industrial sectors.

The development of highly specific biomimetic recognition material is a challenge for rapid detection of harmful residues in foodstuff. In this study, a paper-based boronate affinity metal-organic framework/molecularly imprinted polymer microfluidic chip (FZS-BA@MIP) was constructed based on the in situ construction strategy, which was also designed as a highly specific biomimetic recognition module. Here, the homogeneous zeolitic imidazole framework-8 (ZIF-8) membrane served as a great scaffold and enrichment layer. Besides, the recognition layer of MIP was prepared based on a highly oriented boronate affinity surface imprinting strategy. With the aid of the liquid flow channel, the highly specific enrichment and visual detection for antibiotic residues like kanamycin in actual products were achieved on the paper chip module of an integrated lateral flow platform. The whole analysis process could be accomplished within 30 min. In brief, this study offered a new integrated biomimetic recognition platform for visually detecting harmful veterinary residues containing cis-diols, which demonstrated promising commercial value in point-of-care testing of foodborne hazardous compounds.

It is generally perceived that a substantial number of engineering faculty are still unaware of alternative educational methods, and many who are aware of them choose not to incorporate them into their approach to teaching. There are several likely reasons for this inertia, aside from the inevitable human resistance to change. The primary focus of imparting information is restricted to fulfilling the course requirements and, the upcoming term end examination. It is imperative to adopt a change from teaching to learning paradigm engaging the students in Higher Order Thinking Skills. Knowledge and technological advancements are changing the role of engineering and engineering faculty in the society. Engineering Education reforms need to focus on inductive teaching and stimulated learning. Students should be taught critical thinking skills and creative thinking skills to keep pace with the rapidly changing engineering profession. This paper reports the study done to test and explore the faculty awareness of Bloom's Taxonomy of Educational Objectives in the cognitive domain and Higher Order Thinking Skills (HOTS) and to evaluate question papers set by engineering faculty with respect to HOTS as proposed by Bloom's Taxonomy. Various active learning strategies to enhance critical thinking skills and creative thinking skills of the students are recommended for use by the faculty in their interactions with the students.

Loop-mediated isothermal amplification (LAMP) has been widely used to detect many infectious diseases. However, minor inconveniences during the steps of adding reaction ingredients and lack of simple color results hinder point-of-care detection. We therefore invented a fluorometric paper-based LAMP by incorporating LAMP reagents, including a biotinylated primer, onto a cellulose membrane paper, with a simple DNA fluorescent dye incubation that demonstrated rapid and accurate results parallel to quantitative polymerase chain reaction (qPCR) methods. This technology allows for instant paper strip detection of methicillin-resistant Staphylococcus aureus (MRSA) in the laboratory and clinical samples. MRSA represents a major public health problem as it can cause infections in different parts of the human body and yet is resistant to commonly used antibiotics. In this study, we optimized LAMP reaction ingredients and incubation conditions following a central composite design (CCD) that yielded the shortest reaction time with high sensitivity. These CCD components and conditions were used to construct the paper-based LAMP reaction by immobilizing the biotinylated primer and the rest of the LAMP reagents to produce the ready-to-use MRSA diagnostic device. Our paper-based LAMP device could detect as low as 10 ag (equivalent to 1 copy) of the MRSA gene mecA within 36-43 min, was evaluated using both laboratory (individual cultures of MRSA and non-MRSA bacteria) and clinical blood samples to be 100% specific and sensitive compared to qPCR results, and had 35 day stability under 25 °C storage. Furthermore, the color readout allows for quantitation of MRSA copies. Hence, this device is applicable for point-of-care MRSA detection.

Academic writing, particularly writing research articles, is an indispensable part of every major in higher education. Hyland (2004) argued that a valuable means of exploring academic writing, and comparing the rhetorical features and preferences of different discourse communities, is through the metadiscourse analysis of the text. The present study examines the differences in the use, type, and frequency of interactional metadiscourse markers in the introduction and conclusion sections of research papers across the two disciplines of Mechanical and Electrical Engineering. To this end, 42 research articles (21 Mechanical and 21 Electrical Engineering) written by English native speakers were randomly selected from two major international journals. The current study made use of Hyland's (2005) model for analyzing the interactional metadiscourse markers used in the selected corpus, consisting of 41484 words. To analyze the data, the frequency, patterns of use, and type of interactional metadiscourse markers were elicited both through a manual corpus analysis and concordance package. Furthermore, to examine whether there is any significant difference in the use of metadiscourse markers in the introduction and conclusion sections of these papers, a Chi-square analysis was run. The results of the quantitative analysis revealed that although there were some minor differences in the frequency and type of these metadiscourse markers, there was no statistically significant difference across the disciplines, which can be attributed to the close nature of these fields. The findings of this study may render some pedagogical implications for ESP courses and especially writing research papers.

In the present article we report a new hybrid microfluidic device (hyFlow) comprising a disposable paper electrode and a three-dimensional (3D) printed plastic chip for the electrochemical detection of a magnetic bead-silver nanoparticle (MB-AgNP) bioconjugate. This hybrid device evolved due to the difficulty of incorporating micron-scale MBs into paper-only fluidic devices. Specifically, paper fluidic devices can entrap MB-containing conjugates within their cellulose or nitrocellulose fiber matrix. The hyFlow system was designed to minimize such issues and transport MB conjugates more efficiently to the electrochemical detection zone of the device. The hyFlow system retains the benefit of fluid transport by pressure-driven flow, however, no pump is required for its operation. The hyFlow device is capable of detecting either pre-formed MB-AgNP conjugates or conjugates formed in situ. The detection limit of AgNPs using this device is 12 pM, which represents just 22 AgNPs per MB.

Paper-based microfluidic devices are an attractive platform for developing low-cost, point-of-care diagnostic tools. As paper-based devices' detection chemistries become more complex, more complicated devices are required, often entailing the sequential delivery of different liquids or reagents to reaction zones. Most research into flow control has been focused on introducing delays. However, delaying the flow can be problematic due to increased evaporation leading to sample loss. We report the use of a CO2 laser to uniformly etch the surface of the paper to modify wicking speeds in paper-based microfluidic devices. This technique can produce both wicking speed increases of up to 1.1× faster and decreases of up to 0.9× slower. Wicking speeds can be further enhanced by etching both sides of the paper, resulting in wicking 1.3× faster than unetched channels. Channels with lengthwise laser-etched grooves were also compared to uniformly etched channels, with the most heavily grooved channels wicking 1.9× faster than the fastest double-sided etched channels. Furthermore, sealing both sides of the channel in packing tape results in the most heavily etched channels, single-sided, double-sided, and grooved, wicking over 13× faster than unetched channels. By selectively etching individual channels, different combinations of sequential fluid delivery can be obtained without altering any channel geometry. Laser etching is a simple process that can be integrated into the patterning of the device and requires no additional materials or chemicals, enabling greater flow control for paper-based microfluidic devices.

In cigarette production, the cellulosic paper essentially derived from flax fibers or other fiber materials is used as the wrapping material. During smoking of cigarettes, the highly toxic carbon monoxide is produced. To decrease the amount of carbon monoxide emission in the mainstream smoke, the engineering of all cigarette components including cellulosic cigarette paper and tobacco column is critical. This review summarizes the concepts related to engineering of cigarette paper. These mainly include permeability control, increased use of burn additives, optimization of fiber basis weight, engineering of calcium carbonate fillers, and incorporation of catalysts/oxidants. In particular, catalytic and/or oxidative conversion of carbon monoxide to carbon dioxide has been very widely reported. The control of permeability/diffusivity of cigarette paper is also of critical importance for enhanced diffusion of carbon monoxide out of the cigarette. The development of new concepts and combination of various concepts may lead to breakthroughs in this area., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Mentzer and Becker (2011) and Becker and Mentzer (2012) demonstrated that high school students engaged in engineering design problems spent more time accessing information and spent more time designing when provided with Internet access. They studied high school students engaged in an engineering design challenge. The two studies attempted to apply the same research methodology as was used in previous work by Atman to facilitate comparison between high school students and experts. The 2011 study included Internet access, but the 2012 study did not. Their work showed that with Internet access, students spent an average of 137 minutes engaged in designing a playground and students allocated 47 minutes (35%) to information access. Without Internet access, similar students from the same schools on the same design problem spent an average of 92 minutes of which, 10 minutes (10%) was dedicated to information access. With limited computer access or limited time to enable students to access a computer in some classrooms, the research questions guiding this study are: (1) What information do high school students spend time accessing during an engineering design challenge? How much information comes from paper-based resources as compared to the Internet?; and (2) How much time do they spend accessing information? What is the balance of time spent accessing information from paper-based sources as compared to the Internet? Findings and implications of this research on student learning are discussed. Recommendations for future research are also offered. (Contains 5 tables and 1 figure.)

The sparse literature on the use of imperatives in research papers suggests that they are relatively common in a small number of disciplines, but rare, if used at all, in others. The present study addresses the use of imperatives in a corpus of upper-level A-graded student papers from 16 disciplines. A total of 822 papers collected within the past 5 years were analyzed for imperative use, with particular emphasis placed on the main text of papers from the five disciplines with the highest proportion of imperatives. In each of these disciplines, text-based interviews were conducted with faculty members to establish disciplinary contexts. Results show that imperatives are used frequently in physics, philosophy, economics, mechanical engineering, and linguistics, though in quite varying ways. The interview data suggest that successful and experienced student writers adopt the potentially "high risk strategy" (Hyland 2012) of initiating a sentence with an imperative for various strategic purposes that are discipline-specific. Such insights have implications for writing instructors and materials designers in both L1 and L2 contexts.

Background: To accurately measure students' science, technology, engineering and mathematics (STEM) career interest, researchers must get inside the 'black box' to understand students' conceptualizations of STEM careers., Aims: The aim of Study 1 was to explore whether students' conceptualizations of STEM included medical careers. The aim of Study 2 was to explore whether predictors of STEM career interest (e.g., gender and motivation) varied by STEM definition (inclusion/exclusion of medical careers)., Samples: In Study 1, the sample was US college students (N = 125) who were mostly White (80%). In Study 2, the sample was US 10th-grade high school students (N = 455) who were mostly Black (79%)., Methods: In Study 1, students completed an online questionnaire. In Study 2, students completed various measures of math achievement, motivation (science and math expectancies of success, interest and importance value) and career interest with an importance., Results: In Study 1, medical careers were less often classified as STEM careers than traditional STEM careers, but more often classified as STEM than non-STEM careers. In Study 2, science importance value was the only motivational predictor of students' STEM+Medicine career interest, and no motivation constructs predicted traditional STEM career interest. Boys expressed greater interest in traditional STEM careers, while girls expressed greater interest in STEM+Medicine careers., Conclusions: Students' conceptualizations of STEM are not binary. Thus, we recommend researchers are explicit about their definition of STEM with study participants, in their coding and in their publications., (© 2023 British Psychological Society.)

This paper introduces a novel software framework to support automated development of paper-based microuidic devices. Compared to existing lab-on-a-chip technologies, paper-based microuidics difiers in terms of substrate technologies and point-of-care usage across a wide variety environmental conditions. This paper addresses the contexts in which the software can address these challenges and presents several initial case studies that demonstrate the capabilities of the framework to produce workable and usable paper microuidic devices.

Paper microfluidic devices (including lateral flow assays) offer an excellent combination of utility and low cost. Many paper microfluidic devices are fabricated using the Xerox ColorQube line of commercial wax-based color printers; the wax ink serves as a hydrophobic barrier to fluid flow. These printers are capable of depositing four different colors of ink, cyan (C), magenta (M), yellow (Y), and black (K), plus 11 combinations of these colors (CM, CY, CK, MY, MK, YK, CMY, CMK, CYK, MYK, and CMYK), although most researchers use only black ink to print paper microfluidic devices. Recently, as part of a project to develop a computer-aided design framework for use with paper microfluidics devices, we unexpectedly observed that different colors of wax ink behave differently in paper microfluidics. We found that among the single colors of ink, black ink actually had the most barrier failures, and magenta ink had the fewest barrier failures. In addition, some combinations of colors performed even better than magenta: the combinations CY, MK, YK, CMY, CYK and MYK had no barrier failures in our study. We also found that the printer delivers significantly different amounts of ink to the paper for the different color combinations, and in general, the color combinations that formed the strongest barriers to fluid flow were the ones that had the most ink delivered to the paper. This suggests that by simply weighing paper samples printed with all 15 combinations of colors, one can easily find the color combinations most likely to form a strong barrier for a given printer. Finally, to show that deliberate choices of ink colors can actually be used to create new functions in paper microfluidics, we designed and tested a new color-based "antifuse" structure that protects paper microfluidic devices from a typical operator error (addition of too much fluid to the device). Our results provide a set of color choice guidelines that designers can use to control the behavior of their paper microfluidics.