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N–C codoped Fe nanoparticles were used as a dual enzyme mimetic nanozyme. Colorimetric sensing platforms of antibiotics are important for environmental analysis. The superparamagnetism of Fe–N–C was conducive to its recycling and reuse.

Realizing real-time monitoring of physiological signals is vital for preventing and treating chronic diseases in elderly individuals. However, wearable sensors with low power consumption and high sensitivity to both weak physiological signals and large mechanical stimuli remain challenges. Here, a flexible triboelectric patch (FTEP) based on porous-reinforcement microstructures for remote health monitoring has been reported. The porous-reinforcement microstructure is constructed by the self-assembly of silicone rubber adhering to the porous framework of the PU sponge. The mechanical properties of the FTEP can be regulated by the concentrations of silicone rubber dilution. For pressure sensing, its sensitivity can be effectively improved fivefold compared to the device with a solid dielectric layer, reaching 5.93 kPa−1 under a pressure range of 0–5 kPa. In addition, the FTEP has a wide detection range up to 50 kPa with a sensitivity of 0.21 kPa−1. The porous microstructure makes the FTEP ultra-sensitive to external pressure, and the reinforcements endow the device with a greater deformation limit in a wide detection range. Finally, a novel concept of the wearable Internet of Healthcare (IoH) system for real-time physiological signal monitoring has been proposed, which could provide real-time physiological information for ambulatory personalized healthcare monitoring.

Summary In this paper, a meshless numerical modeling method named mesh-free discrete fracture model (MFDFM) of fractured reservoirs based on the newly developed extended finite volume method (EFVM) is proposed. First, matching and nonmatching point cloud generation algorithms are developed to discretize the reservoir domain with fracture networks, which avoid the gridding challenges of the reservoir domain in traditional mesh-based methods. Then, taking oil/water two-phase flow in fractured reservoirs as an example, MFDFM derives the EFVM discrete scheme of the governing equations, constructs various types of connections between matrix nodes and fracture nodes, and calculates the corresponding transmissibilities. Finally, the EFVM discrete scheme of the governing equations and the generalized finite difference discrete scheme of various boundary conditions form the global nonlinear equations, which do not increase the degree of nonlinearity compared with those in the traditional finite volume method (FVM)-based numerical simulator. The global equations can be solved by the existing nonlinear solver in the FVM-based reservoir numerical simulator by only adding the linear discrete equations of boundary conditions, which reduce the difficulty of forming a general purpose MFDFM-based fractured reservoir numerical simulator. Several numerical test cases are implemented to illustrate that the proposed MFDFM can achieve good computational performance under matching and nonmatching point clouds, and for heterogeneous reservoirs, complex fracture networks, complex boundary geometry, and complex boundary conditions, by comparing the computational results of MFDFM with embedded discrete fracture model (EDFM). Thus, MFDFM retains the computational performances of the traditional mesh-based methods and can avoid the difficulties of handling complex geometry and complex boundary conditions of the computational domain, which is the first meshless numerical framework to model fractured reservoirs in parallel with the mesh-based discrete fracture model (DFM) and EDFM.

With the rapid development of economy and culture, people's home decoration not only stays practical, but also emphasizes aesthetics, creativity and environmental protection, and the home improvement industry has ushered in rapid development. The traditional decoration industry also has obvious drawbacks such as long construction period, opaque price, and unnecessary construction. With the introduction of supply-side reforms, the home improvement industry also urgently needs to improve efficiency, thereby reducing the home improvement burden that modern residents are increasingly concerned about. In response to this problem, the "i-Home Yunju" smart APP was first developed. By exploring the relevant functions of the APP and carrying out innovative design, at the same time, the feasibility of AR and VR technology was analyzed to explore the importance of virtual reality technology to smart home decoration.

Canadian multicultural and Indigenous picturebooks greatly influence both children’s and educators’ being and becoming. Identity is closely related to our engagement with literacy practices, including book reading. In this paper, two researchers who immigrated from Mainland China engage in autobiographical narrative inquiry, a methodology that asks the researchers to self-face, and to “world”-travel to our earlier landscapes, times, places, experiences, and relationships. In personal, educational, and academic settings, we tell and retell our storied experiences of critically reading four multicultural and Indigenous Canadian picturebooks, to fight the hegemony of the Canadian dominant culture. Our article sheds light on the importance of negotiating one’s identity in multicultural and Indigenous picturebooks, as little work presents minority educators’ and adult newcomers’ voices of reading diverse Canadian picturebooks. By making visible our critical reading experiences, this inquiry opens space to maximize the outcomes of utilizing children’s literature in teaching and learning.

A raindrop solar cell can work either on rainy days to collect mechanical energy of the raindrops or on sunny days to harvest solar energy, which achieves high energy conversion efficiency in various energy environments. However, the low efficiency of raindrop energy harvesting is a dominating barrier to the raindrop solar cells in practical applications. In this work, a MoO

As the basic and essential unit of neuromorphic computing systems, artificial synaptic devices have great potential to accelerate high-performance parallel computation, artificial intelligence, and adaptive learning. Among the proposed artificial synaptic devices, the synaptic transistors are well considered to be one of the most suitable devices for simulating artificial intelligence. So far, synaptic transistors based on iontronic have been proposed and proved to demonstrate great potential in artificial intelligence applications. However, little research specifically focused on improving the device's ability to mimic synaptic behaviour. Here, we proposed the enhancement of synaptic properties of the solution-based thin-film transistors based on potassium ion conduction in the dielectric layer for the first time. Due to the formation of a gated electrical double-layer, the transistor exhibited an enlarged memory window. Based on this, the excitatory postsynaptic current in the synaptic thin-film transistor was modified accordingly, which further enhanced the suitability of the proposed synaptic thin-film transistor for simulating biological synapses. In addition, considerable synaptic properties were evaluated elaborately, including paired-pulse facilitation, short-term memory, long-term memory, and spike-time-dependent-plasticity. Most importantly, according to the impressive results of the Artificial Neural Network algorithm's image recognition simulation, the simulation image recognition rate based on the mentioned artificial synaptic devices reached as high as 92%. Last but not least, in order to simulate biological neurobehavior more closely, the Spiking Neural Network algorithm was also successfully implemented to complete the specified machine learning task, which further proved the great potential of the synaptic devices in advanced low-power neural network systems.

Background The ex vivo study is to compare the root canal preparation outcomes achieved by five nickel–titanium single-file instrumentation systems (M3-L, Reciproc Blue, V-Taper 2H, WaveOne Gold, XP-endo Shaper) in severely curved molar root canals. Methods A total of 60 root canals were selected from extracted human molar teeth with curvatures ranging from 25° to 50° and divided into five groups based on the instrumentation system employed (n = 12). Before and after root canal preparation, a Micro-CT scan was taken, and pre- and post-operative data were analyzed to evaluate the following parameters: volume increment of root canals (VI), untouched root canal areas (UTA), and canal transportation (CT). Apically extruded debris (AD) was collected during preparation. After that, all samples were separated into two parts and examined respectively by scanning electron microscope (SEM) to assess cleaning ability. Data were statistically analyzed with ANOVA (UTA, AD, VI) or Kruskal–Wallis test (CT, SEM-score), the level of significance was set at α = 0.05. Results There were no significant differences between the five systems regarding the AD, VI, and UTA parameters (P > 0.05). In terms of CT, no significant difference was noted at the straight section of canal and apical levels, while XP-endo Shaper showed less canal transportation than M3-L at the level of curved vertex (P P P P P Conclusion The five single-file systems evaluated performed equally in apically debris extrusion, dentin removal, and untouched root canal areas, while XP-endo Shaper and V-Taper 2H resulted in less canal transportation compared to M3-L and WaveOne Gold. Regarding cleaning ability, Reciproc Blue and XP-endo Shaper were associated with less smear layer than WaveOne Gold in the apical thirds.

The oral microbiome, associated with both oral disease and systemic disease, is in dynamic status along the whole life, and many factors including maternal microbiomes could impact the oral microbiome. While fewer studies have been conducted to study the characteristics of the oral microbiome in neonates and the associated maternal factors. Hence, we collected the microbiome of 15 mother-infant pairs across multiple body sites from birth up to 4 days postpartum and used high-throughput sequencing to characterize the microbiomes in mothers and their neonates. The oral microbiome in the neonates changed obviously during the 4 days after birth. Many bacteria originating from the vagina, skin, and environment disappeared in oral cavity over time, such as Prevotella bivia and Prevotella jejuni. Meanwhile, Staphylococcus epidermidis RP62A phage SP-beta, predominate bacterium in maternal skin microbiome and Streptococcus unclassified, main bacterium in vaginal microbiome, obviously increased in neonatal oral microbiome as time went on. Interestingly, as time progressed, the composition of the oral microbiome in the neonates was more similar to that of the milk microbiome in their mothers. Moreover, we found that the changes in the predominant bacteria in the neonates were in line with those in the neonates exposed to the environment. Together, these data described the sharp dynamics of the oral microbiome in neonates and the importance of maternal efforts in the development of the neonatal microbiome.

Background To evaluate the root canal preparation outcomes achieved by five nickel-titanium single-file instrumentation systems (M3-L, Reciproc Blue, V-Taper 2H, WaveOne Gold, XP-endo Shaper) in severely curved molar root canals. Methods A total of 60 root canals were selected from extracted human molar teeth with curvatures ranging from 25° to 50° and divided into five groups based on the instrumentation system employed (n = 12). Before and after root canal preparation, a Micro-CT scan was taken, and pre- and post-operative data were analyzed to evaluate the following parameters: volume increment of root canals (VI), untouched root canal areas (UTA), and canal transportation (CT). Apically extruded debris (AD) was collected during preparation. After that, all samples were separated into two parts and examined respectively by scanning electron microscope (SEM) to assess cleaning ability. Data were statistically analyzed with ANOVA (UTA, AD, VI) or Kruskal-Wallis test (CT, SEM-score), the level of significance was set at α = 0.05. Results There were no significant differences between the five systems regarding the AD, VI, and UTA parameters (P > 0.05). In terms of CT, no significant difference was noted at the straight section of canal and apical levels, while XP-endo Shaper showed less canal transportation than M3-L at the level of curved vertex (P P P P P

It is reported a convenient method to obtain flame-retardant polylactic acid composite by adding low amount of crystal form II ammonium polyphosphate (APP-II) or nano-compound of crystal form II ammonium polyphosphate with calcium-based montmorillonite. The structures and thermal properties of the crystal form II ammonium polyphosphate and crystal form II ammonium polyphosphate with calcium-based montmorillonite were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. Crystallography and morphologies of the polylactic acid and its composites with the crystal form II ammonium polyphosphate and crystal form II ammonium polyphosphate with calcium-based montmorillonite were measured through differential scanning calorimeter and scanning electron microscopy. In flame retardancy of the polylactic acid composites, the 5 wt% crystal form II ammonium polyphosphate could make the polylactic acid achieve the UL-94 vertical burning V-0 rating and limited oxygen index 27.3%. When using crystal form II ammonium polyphosphate with calcium-based montmorillonite in flame-retarding polylactic acid, only 3 wt% nano-compound can result in the same V-0 rating level and the limited oxygen index of 28.0%. Meanwhile, polylactic acid with crystal form II ammonium polyphosphate or crystal form II ammonium polyphosphate with calcium-based montmorillonite still keeps the good mechanical properties. The developed systems are environmentally friendly and highly effective flame retarding, which show a promising future in practical large-scale polylactic acid application.

During the COVID-19 pandemic teachers have been expected to learn new digital literacy skills, often applying them immediately. While professional development structures within school districts and professional associations are organized to offer supports, teachers may be challenged to gain digital skills within existing professional development models. Within our study, teachers explored technologies with the aim of rethinking frames for teaching and learning literacy. Following the start of the COVID-19 pandemic they shared their experiences, insights and challenges. In our article, we address implications for digital literacy teaching and learning and the need for new ways of approaching teacher development.

As one of the promising next-generation electronics, brain-inspired synaptic resistive random access memory (RRAM) devices with stacked solution-processed (SP) spin-coated resistive switching (RS) ...

Levels of extracellular histones are highly increased in sepsis and may facilitate microcirculatory dysfunction. Unfractionated heparin (UFH) binds histones and neutralizes their cytotoxicity. We investigated the effect of UFH on microcirculatory dysfunction by interacting with extracellular histones in endotoxemic rats.Twenty-four Wistar rats were randomly divided into three groups: control, lipopolysaccharide (LPS) group, and LPS + UFH group. In the LPS and LPS + UFH groups, 10 mg/kg LPS was injected to induce endotoxemia, and 100 IU/kg/h UFH was administered intravenously in the LPS + UFH group. The rats underwent midline laparotomy, and then intestinal microcirculation was evaluated using an incident dark field microscope. Circulating histones and microstructures of the rat intestinal microvascular endothelium were also detected. Additionally, the antagonistic effect of UFH on histone-induced cytotoxicity was investigated in human intestinal microvascular endothelial cells.UFH protected the microcirculation of the intestinal serosa and mucosa in endotoxemic rats, as evidenced by increased total vessel density, perfused vessel density, and proportion of perfused vessels of both the serosa and mucosa, and increased microcirculatory flow index of the mucosa in the LPS + UFH group. UFH treatment decreased the levels of circulating histones and alleviated intestinal microvascular endothelial injuries in endotoxemic rats. Furthermore, UFH inhibited histone cytotoxicity in vitro.UFH attenuated microcirculatory dysfunction in endotoxemic rats by antagonizing extracellular histones, thereby providing a potential therapeutic strategy for sepsis.

Highlights A hybridized mechanical and solar energy-driven hydrogen production system was developed.A rotatory disc-shaped triboelectric nanogenerator (RD-TENG) enables to harvest mechanical energy from water flow and functions as a sufficient external power source.WO3/BiVO4 heterojunction is fabricated as photoanodes in the self-powered photoelectrochemical (PEC) cell, and the hydrogen production rate reaches to 7.27 μL min−1 under sunlight illumination with the energy conversion efficiency of 2.59%. Electronic supplementary material The online version of this article (10.1007/s40820-020-00422-4) contains supplementary material, which is available to authorized users., Photoelectrochemical hydrogen generation is a promising approach to address the environmental pollution and energy crisis. In this work, we present a hybridized mechanical and solar energy-driven self-powered hydrogen production system. A rotatory disc-shaped triboelectric nanogenerator was employed to harvest mechanical energy from water and functions as a sufficient external power source. WO3/BiVO4 heterojunction photoanode was synthesized in a PEC water-splitting cell to produce H2. After transformation and rectification, the peak current reaches 0.1 mA at the rotation speed of 60 rpm. In this case, the H2 evolution process only occurs with sunlight irradiation. When the rotation speed is over 130 rpm, the peak photocurrent and peak dark current have nearly equal value. Direct electrolysis of water is almost simultaneous with photoelectrocatalysis of water. It is worth noting that the hydrogen production rate increases to 5.45 and 7.27 μL min−1 without or with light illumination at 160 rpm. The corresponding energy conversion efficiency is calculated to be 2.43% and 2.59%, respectively. All the results demonstrate such a self-powered system can successfully achieve the PEC hydrogen generation, exhibiting promising possibility of energy conversion. Electronic supplementary material The online version of this article (10.1007/s40820-020-00422-4) contains supplementary material, which is available to authorized users.

Studies assessing the environmental impacts of oil spills focus primarily on the non-water-soluble components, leaving the fate of the water-soluble fraction (WSF) largely unexplored. We employed u...

Developing fluid velocity sensors with high accuracy, high stability and self-power has practical significance. Triboelectric sensors provide a strategy to realize high-performance self-powered active sensing. In this article, we present a fully enclosed self-powered active spherical triboelectric sensor (SASTS) to detect the fluid velocity. Based on the electrification at the contact interface, resulting in the electrostatic induced electrons transferring between two interdigitated electrodes, SASTS effectively harvests the fluid flow energy to electric signal. After Fourier transform processing of the output signal, the motion frequency of the SASTS can be distinguished and the fluid velocity can be further calculated. By optimizing the structure parameter, it features high precision with average standard deviation less than 4, wide range speed from 2 m/s to 18 m/s of fluid flow, and proved lifetime more than half a year. This technique can be applied to measurement of fluid flow speed, even potentially to other rotation movements, which could have wide applications, such as environment monitoring, transportation and so on.

The spatial layout of urban villages seriously affects the living environment and integrated development of urban and rural areas. Using digital means to assist in the reconstruction of urban villages is necessary and urgent. This study built an urban renewal framework for intelligent building planning with a proposed multi-party collaborative pattern. First, villagers’ needs, and relevant standards and regulations were merged into planning requirements, which were formulated into planning goals and criteria. With the quantitative goals and criteria, building planning and design algorithms were developed. Furthermore, the method was verified to achieve an intelligent layout of buildings. Finally, under certain conditions, the average difference between the plot ratio calculated by the program and the actual plot ratio was 0.02, and that between the building intensity calculated by the program and the actual building intensity was 0.02. Within 11.43 hectares, 500 buildings were generated with a total floor area of 27.72 hectares, and the average time taken for scheme generation was 10 s. This method can efficiently generate a plan similar to the actual floor area ratio and building density and optimize the problem of insufficient spacing. Moreover, adjusting the parameters can automatically generate a variety of schemes that can support the layout design of rural buildings.

As accurate step counting is a critical indicator for exercise evaluation in daily life, pedometers give a quantitative prediction of steps and analyze the amount of exercise to regulate the exercise plan. However, the merchandized pedometers still suffer from limited battery life and low accuracy. In this work, an integrated self-powered real-time pedometer system has been demonstrated. The highly integrated system contains a porous triboelectric nanogenerator (P-TENG), a data acquisition and processing (DAQP) module, and a mobile phone APP. The P-TENG works as a pressure sensor that generates electrical signals synchronized with users' footsteps, and combining it with the analogue front-end (AFE) circuit yields an ultrafast response time of 8 ms. Moreover, the combination of a mini press-to-spin-type electromagnetic generator (EMG) and a supercapacitor enables a self-powered and self-sustained operation of the entire pedometer system. This work implements the regulation of TENG signals by electronic circuit design and proposes a highly integrated system. The improved reliability and practicality provide more possibilities for wearable self-powered electronic devices.

Al/TE (top electrode)/AlOx/Pt RRAM (resistive random access memory) devices with solution-processed spin-coated AlOx layers annealed at various temperatures (225/250/275 °C) exhibited typical bipolar resistive switching performance with low SET/RESET voltage ( 103) and excellent stability (retention time over 104 s and endurance cycles more than 100). Ni and TiN were chosen as the TE, respectively. Better RS characteristics were obtained on Ni/AlOx/Pt RRAM devices with lower operating voltage and better stability. In addition, the voltage variation between Ni/AlOx/Pt and TiN/AlOx/Pt RRAM devices was investigated. Compared with Ni/AlOx/Pt RRAM devices, TiN/AlOx/Pt devices operated with higher operation voltage at various annealing temperatures, which indicated the influence of work function difference (△ΦM) between TE and BE (bottom electrode). The greater the △ΦM, the more energy consumption and the higher operation voltage were demanded.

The highly parallel artificial neural systems based on transistor-like devices have recently attracted widespread attention due to their high-efficiency computing potential and the ability to mimic biological neurobehavior. For the past decades, plenty of breakthroughs related to synaptic transistors have been investigated and reported. In this work, a kind of photoelectronic transistor that successfully mimics the behaviors of biological synapses has been proposed and systematically analyzed. For the individual device, MXenes and the self-assembled titanium dioxide on the nanosheet surface serve as floating gate and tunneling layers, respectively. As the unit electronics of the neural network, the typical synaptic behaviors and the reliable memory stability of the synaptic transistors have been demonstrated through the voltage test. Furthermore, for the first time, the UV-responsive synaptic properties of the MXenes floating gated transistor and its applications, including conditional reflex and supervised learning, have been measured and realized. These photoelectric synapse characteristics illustrate the great potential of the device in bio-imitation vision applications. Finally, through the simulation based on an artificial neural network algorithm, the device successfully realizes the recognition application of handwritten digital images. Thus, this article provides a highly feasible solution for applying artificial synaptic devices to hardware neuromorphic networks.

The components in traditional human–machine interaction (HMI) systems are relatively independent, distributed and low-integrated, and the wearing experience is poor when the system adopts wearable electronics for intelligent control. The continuous and stable operation of every part always poses challenges for energy supply. In this work, a triboelectric technology-based all-in-one self-powered HMI system for wireless remote telemetry and the control of intelligent cars is proposed. The dual-network crosslinking hydrogel was synthesized and wrapped with functional layers to fabricate a stretchable fibrous triboelectric nanogenerator (SF-TENG) and a supercapacitor (SF-SC), respectively. A self-charging power unit containing woven SF-TENGs, SF-SCs, and a power management circuit was exploited to harvest mechanical energy from the human body and provided power for the whole system. A smart glove designed with five SF-TENGs on the dorsum of five fingers acts as a gesture sensor to generate signal permutations. The signals were processed by the microcontroller and then wirelessly transmitted to the intelligent car for remote telemetry and control. This work is of paramount potential for the application of various terminal devices in self-powered HMI systems with high integration for wearable electronics.

MXenes are a large class of two-dimensional (2D) materials widely studied recently since they have good water solubility and are able to tune the work function (WF) of materials without changing their electronic characteristics. Based on this, aqueous solution-processed indium-free zinc tin oxide (ZTO) thin-film transistors (TFTs) have been fabricated under an annealing temperature of 300 °C and successfully optimized. This optimization is achieved by fabricating a channel layer into a homojunction structure (MXene doped ZTO/ZTO) to form a two-dimensional electron gas (2DEG). Through doping the specific concentrations of Ti3C2Tx MXenes into the upper layer ZTO thin films, the TFTs exhibit enhanced field-effect mobilities (μFE) of 10.77 cm2 V−1 s−1 and 13.06 cm2 V−1 s−1 as well as a large on/off current ratio of more than 108. Moreover, compared with the undoped double-layer ZTO TFTs, the homojunction devices show better stability, mainly resulting from the transformation in leading conduction mode. Finally, through applying the homojunction channel on the solution-processed aluminum oxide (AlOx) dielectric layer, the μFE exhibits a further enhanced value of 28.35 cm2 V−1 s−1. This is the first report to apply MXenes to the channel layer of TFTs and to fabricate solution-processed ZTO thin films via an aqueous solvent under 300 °C.

The 13th Annual Graduate Research Showcase was held by the Department of Secondary and Elementary Education Graduate Students’ Associations on May 1, 2021. As our first virtual research showcase, graduate student presenters and participants gathered in virtual spaces to celebrate and share our research, and engage in conversation with colleagues. We appreciate and are grateful for the opportunity provided by the Alberta Academic Review to publish a special issue to present the conference proceedings.

Forest soil dissolved organic matter (DOM) is a major source of terrigenous dissolved organic carbon (DOC) that is an important component of biogeochemical cycles. While many studies have shown tha...