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Summary Mechanoreceptors are essential components of the somatosensory system that convert received mechanical signals into electrical signals that can be sent to the brain. These receptors provide the ability to sense a variety of stimuli from the external environment, including touch, vibration, and heat. Mechanoreceptors do not convert signals monotonically; in addition, several fundamental characteristics are embedded in mechanoreceptors, including thresholds and adaptation properties. In this study, we proposed and experimentally demonstrated a van der Waals stacking field-effect transistor (VS-FET), which was inspired by an FET with a floating gate structure, to realize the important characteristics of mechanoreceptors. The VS-FET can not only demonstrate the fundamental biological functions but also produce other unique properties such as fatigue and accommodation. We also integrated an artificial touch receptor with an array of the proposed VS-FET to demonstrate the feasibility of these devices experimentally in artificial humanoid systems.

Over the last decade, various rating systems and indicators have been proposed for evaluating or certifying roadway sustainability. However, there is no systematic method for the roadway projects to adopt the indicators of the rating systems to enhance sustainability for certification. This study developed a strategy for adopting indicators in a roadway rating system for sustainability certification. First, the framework and rules for prioritizing the indicators were established from literature review. Then, carbon emissions, costs, and the difficulties of employing the indicators were analyzed in a roadway case study. Finally, the priorities for adopting the indicators were determined. The results revealed that the indicators with higher score–unit ratios should have higher priorities in the project. By using the developed framework, the simultaneous analysis of multiple dimensions enables appropriate investigation into roadway sustainability problems. The score–unit ratio is a simple but effective metric to evaluate whether a project has incorporated appropriate indicators to enhance sustainability.

Warm-mix asphalt (WMA) is one technology that has been found to have potential in minimizing the environmental harm caused by road construction activities. Its low mixing and compacting temperatures have opened great opportunities for more sustainable development. However, because WMA is mixed at low temperatures, the drying process of the aggregate may fail to dry the WMA completely. The binder-aggregate adhesion property can be damaged by moisture remaining from incomplete drying. The present study investigated the effects of aggregate moisture on the binder-aggregate interfacial characteristics of WMA by evaluating its surface free energy and adhesive bond strength. The results showed that for the Pen 60-70 binder type, the aggregate AG in general showed the higher bond energy and aggregate SD showed the lowest bond energy among three aggregate types. Also, the bond energy diminishes with increasing aggregate moisture contents but the percent drops in bond energy is less when WMA additives was included. For the PM binder, SL aggregate group showed the highest bond energy and SD aggregate group showed the lowest bond energy. For the work of adhesion, the results showed that with aggregate with 10% moisture contents has destructive effects on the work of adhesion which may decrease to 50% compare to dry aggregate condition. Finally, the four quadrant diagrams can be used to combine two distinct property of the bond energy and the work of adhesion as the hybrid performance indicator to rank the effect of moist aggregate to the adhesion properties at binder-aggregate interface.

Currently, road and airport pavement construction uses approximately 90% asphalt, most of which is mainly derived from fossil fuels. However, with the improvement in oil refinery technology, the quality of asphalt binders is degrading gradually. Moreover, from the environment standpoint, fossil fuels are the main source of greenhouse gases, which lead to global warming. Consequently, there is an urgent need to develop a more sustainable binding material from renewable or other alternative resources to replace or modify the existing petroleum-based asphalt binder for the highway industry. The main objective of this study was to investigate the potential use of a bio-oil byproduct as a partial replacement for a bitumen-based binder. The properties of various blending combinations of a biobinder and asphalt binder were compared with those of an unmodified asphalt binder through several physical and rheological tests. The specific gravity of the biobinder was found to be higher than that of the petroleum-based binder. In general, biobinder blends have a higher viscosity than that of the unmodified binder at temperatures higher than 60 °C. Binders containing the biobinder at 25% and 50% have lower temperature susceptibility than that of the unmodified binder. Adding the biobinder at up to 25% does not significantly change the complex shear modulus of unaged binders, whereas rolling thin-film oven-aged biobinder blends show a higher complex modulus and greater viscosity than those of the unmodified binder. Moreover, the biobinder blends show higher G ∗ /sin δ, lower nonrecoverable compliance and greater recovery ability than those of conventional AC-20.

Frequent mill and overlay activities result in the production of a considerable amount of reclaimed asphalt pavement (RAP) materials. Many pavements that incorporated RAP exhibit a shorter service life than do those without RAP. One of the possible reasons is that certain RAP materials have already undergone multiple recycling processes during the past decade. This results in severe aging of the reclaimed asphalt binder (RAB). In this study, three severely aged RABs, two RAP blending scenarios, two virgin binders, and two commercial rejuvenators were used to investigate the feasibility of using severely aged binders for constructing pavements. The chemical and rheological properties of the rejuvenated severely aged binders were evaluated using high-performance gel permeation chromatography and a dynamic shear rheometer. The molecular size distributions of rejuvenated RABs revealed that the rejuvenators used in this study could rebalance the proportions of large, medium, and small molecular components among the rejuvenated RABs. However, the polydispersity values still enabled clearly distinguishing between virgin binders and rejuvenated RABs. Two performance parameters were used to evaluate the potential of age-induced damage as well as permanent rutting in the binders. A Glover–Rowe damage zone was evaluated, and it revealed promising results to distinguish among severely aged binders, virgin binders, and rejuvenated binders. Oscillation and multiple stress creep and recovery tests were performed to obtain rutting potential parameter G ∗ /sin( δ ) and J nr , respectively. The results indicated that all rejuvenated aged binders exhibited higher G ∗ /sin( δ ) values and lower J nr values compared with the control virgin binders.

This study applied Garrison, Anderson, and Archer's (2000) community of inquiry (CoI) framework to teacher learning by designing and investigating online participatory practice in which 14 prospective teachers (PT) were engaged in collectively evaluating and reconstructing their written feedback in their teaching, cognitive, and social presences. Data included the PTs' action logs in the three presences, their observation notes on fellow teachers' feedback practice, their feedback on students' different versions of texts, and transcripts of discussion forums and chat rooms. Results showed that in an online teacher learning community, the teaching presence reinforced and sustained the cognitive and social presences in the virtual community as the PTs learned to serve as subject matter experts. Through these three presences, the PTs provided micro- and macro-level feedback and observed each other's practices in the teaching presence. An online participatory practice allowed the PTs to recognize problems in feedback practice and develop principles of effective written feedback through collaborative efforts. Practical implications and useful functionalities of an online system for teacher learning were also discussed. Community of Inquiry (CoI) framework has the potential for exploring teacher learning.Design in the teaching presence reinforces and sustains the cognitive and social presences in the online virtual community.Teachers develop principles of effective written feedback through collaborative efforts.

Modern technology allows us to mimic biological functions with artificial devices. The human brain, including numerous neural cells that connect via synapses, enables us to handle complex tasks with ultra-low power consumption, which is one of the most important biological components that eager to emulate. Here, we propose and build a simple indium selenide (InSe)-based photonic synaptic device with unique gate tunable behaviours such as time-varying output current, auto-depression rate, and paired-pulse facilitation (PPF). A new inverse PPF behaviour is observed, characterized by the positive correlations to the time interval, which is opposite of those negative ones in previous studies. To unveil the origin of this new finding, both the substrate-dependent persistent photocurrent examination and low-frequency noise (LFN) measurements are performed to investigate the electric-controlled charge trapping/detrapping processes between the InSe and SiO2 interface. Furthermore, we systematically demonstrate such the specific evolution of the flexible plasticity within a low-operation voltage and a wide range of visible spectra. Interestingly, the inverse PPF can be employed to emulate more detailed characteristics of a biological brain such as the age-related changes of synaptic plasticity in real human brains. Thus, we believed that our findings provide a proof-of-concept for systematically mimicking the brain plasticity and advancing the development of energy-efficient artificial brains.

Display Omitted The Ir-gate AlSb/InAs HEMT on Si substrate has been studied with reliability evaluation.The Ir-gate exhibited a superior metal work function.The Schottky barrier height of InAs/AlSb on silicon was improved.TEM, SIMS, and low frequency noise measurement were adopted to proof device stability. In this work, the 6-inch AlSb/InAs on Si (001) substrate is used to increase device integration and cost-effective purpose. The iridium (Ir)-gate was used for the InAs/AlSb on silicon substrate and temperature-dependent characteristics were also studied. The Ir-gate exhibited a superior metal work function which was beneficial for increasing the Schottky barrier height of InAs/AlSb on silicon heterostructures. Moreover, transmission electron microscopy, secondary ion mass spectrometry, and low frequency noise measurements were conducted to proof that the Ir-gated AlSb/InAs HEMT achieved the better stability of characteristics after self-heating and hot-carrier stresses.

Multifunctional devices are expected to allow development of low-cost, highly integrated, and energy-efficient electronics for the internet of things (IoT) era. Here, we demonstrate an all-two-dimensional ReSe2/h-BN/graphene heterostructure (ReSe2 HS) consisting of a vertically coupled ReSe2 field-effect transistor and charge storage component, which possesses multifunctional characteristics for use in electronics and optoelectronics. As an electrically controlled non-volatile memory (NVM), the ReSe2 HS delivers high-performance multilevel data storage with a readout on/off current ratio exceeding 105 and excellent durability (>104 s) at an ultralow Vds of 50 mV, which benefits to the development of power saving devices. The ReSe2 HS design and high-photoresponsivity ReSe2 channel also achieve an energy efficient optical NVM with full-visible-spectrum distinction. Besides, the ReSe2 HS displays unique ambipolarity to operate as either an inverter or frequency doubler. We further propose a power-free ReSe2 HS optical memory matrix to simplify imaging systems. The ReSe2 HS shows promise for use in light-programmable information storage systems and neuromorphic computation with low power consumption.

An all-inkjet-printed organic thin film transistor (OTFT) with a double-layer dielectric structure is proposed and implemented in this study. By using the double-layer structure with different dielectric materials (i.e., polyvinylphenol with poly(vinylidene fluoride-co-hexafluoropropylene)), the threshold-voltage of OTFT can be adjusted. The threshold-voltage shift can be controlled by changing the composition of dielectric layers. That is, an enhancement-mode OTFT can be converted to a depletion-mode OTFT by selectively printing additional dielectric layers to form a high-k/low-k double-layer structure. The printed OTFT has a carrier mobility of 5.0 × 10 − 3 cm 2 /V-s. The threshold-voltages of the OTFTs ranged between − 13 V and 10 V. This study demonstrates an additional design parameter for organic electronics manufactured using inkjet printing technology.

In recent years, researchers have conducted various studies on applying wireless networking technology and mobile devices in education settings. However, research on behavioral patterns in learners' online asynchronous discussions with mobile devices is limited. The purposes of this study are to develop a mobile learning system, mobile interactive teaching feedback system (MITFS), linked to both mobile devices and the internet, to support learners with online asynchronous discussion, and combine content analysis and sequential analysis to compare and contrast the social knowledge construction behavioral patterns of problem-based asynchronous discussion in e-learning and m-learning environments. This study investigated four weeks of online discussions in an ''Introduction to Computer Science'' course involving forty first year university students. The control group (online asynchronous discussion without mobile devices) and the experimental group (online asynchronous discussion with mobile devices) in the group discussions were explored. By using content analysis and sequential analysis for the problem-based online asynchronous discussion of the behavioral patterns and differences between students in control and experimental group, the results showed that using mobile devices in online asynchronous discussion influenced students' learning performance. Some interesting results were found. Firstly, when the students used mobile devices in discussion situations, they could more engage in reflecting thinking, sharing more information, and further facilitating social knowledge construction among group members. Secondly, the experimental group performed better than the control group in terms of participation and diversity in knowledge construction behavioral patterns. Finally, based upon the findings, some implications are proposed for further research.

BackgroundScabies is a global problem. Transmission of scabies is usually due to direct or indirect contact. Delay in diagnosis may result in the spread of the scabies mite. Prompt diagnosis and treatment are important.MethodsIn this study, we collected data from 52 scabies patients and analyzed the risk factors for scabies with the case-control method.ResultsOur study has revealed that the patients who were bedridden [odds ratio (OR) 6.72, p

Bilateral subthalamic nuclei deep brain stimulation (DBS) has been shown to be effective in treating motor symptoms of Parkinson's disease. Numerous studies confirm the safety and efficacy of DBS. Complications of subthalamic nuclei DBS show a 1.2% risk of symptomatic intracerebral hemorrhage. There are few studies concerning the benefits of rehabilitation after occurrence of intracerebral hemorrhage related to DBS. We report a patient who underwent an inpatient rehabilitation program because of complicated intracerebral hemorrhage after a DBS procedure. We observed significant improvement in locomotion and independence of daily activities after the program. We also review the current literature reporting complications following DBS.

In this study, we investigate the chemical properties and surface morphology of super-hydrophobic (SH) films deposited by self-assembled RF atmospheric-pressure plasma (APP) deposition system. The O2/HMDSN (hexamethyldisilazane) and Ar serve as the deposition precursor and ionization gas, respectively. The effects of process parameters, including the oxygen flow rate and the nozzle-to-sample distance on the characteristics of SiOx films measured by FTIR, XPS, SEM and AFM are also discussed. It was found that the higher deposition rate was obtained at higher oxygen flow rate conditions. Consequently, the smooth surface was transformed into a rough surface with many particles when the nozzle-to-sample distance was decreased from 20 mm to 10 mm. The SH films (contact angle over 150° and sliding angle below 5°) were obtained when the nozzle-to-sample distance was 10 mm. A simplified deposition mechanism is proposed to explain the effect of process parameters on the films that are formed.

In this study, super-hydrophobic films were deposited in a one-step simple process by pulsed RF C6F6 plasma, and the influence of the duty-cycle (DC) on the surface structure and chemical characteristics of depositing fluorocarbon films was examined. The deposited coatings were analyzed by X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectrometry (FTIR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Contact Angle Analyzer. It was found that by decreasing the DC from 1 to 0.1, the rough structure of the film with a lot of particles was obtained. In addition, the super-hydrophobic property was obtained on this composite fluorocarbon film. Finally, the adhesion of fluorocarbon films could be increased by deposited on the cotton fiber substrates instead of Si wafer.

China's economic performance over the past few decades has put China in a position where it now accounts for one-third of global economic growth, twice as much as America. The large-scale growth of China's economy has attracted attentionfrom businesses and investors worldwide [Morrison (2006). China ’ s economic conditions . Congressional Research Service: The Library of Congress]. With the continuing growth of China's economy, more and more people from all over the world are learning Chinese in order to conduct business and access China's huge markets. Correspondingly, an increase in the demand for Chinese speakers is being matched by an increase in available Chinese language teaching jobs globally. This has led many Chinese native speakers to consider teaching Chinese as a second language either in China or overseas. This study is a narrative inquiry into the transformation of thinking about language education, based on the author's experience of teaching Chinese while pursuing a doctorate program at a major university in the United States. The data used in this study are qualitative in nature, consisting of self-observations and journal writing. Narrative inquiry serves as a conceptual framework to this study and was adopted as a tool for data analysis. The analysis focused on how the author, as a teaching assistant from Taiwan, dealt with issues of teaching Chinese as a second language and how he drew on pedagogical theories and methodologies. The author's experience with students in the East Asian Language and Culture Department with their different assumptions and motivations highlighted the importance of teaching strategies and pedagogies in class. Elements like cultural diversity and learning styles are also discussed in this paper.