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Chromism-based optical filters is a niche field of research, due to there being only a handful of electrochromic materials. Typically, electrochromic transition metal oxides such as MoO3 and WO3 are utilized in applications such as smart windows and electrochromic devices (ECD). Herein, we report MoO3-x-based electrically activated ultraviolet (UV) filters. The MoO3-x grown on indium tin oxide (ITO) substrate is mechanically assembled onto an electrically activated proton exchange membrane. Reversible H+ injection/extraction in MoO3-x is employed to switch the optical transmittance, enabling an electrically activated optical filter. The devices exhibit broadband transmission modulation (325-800 nm), with a peak of ∼60% in the UV-A range (350-392 nm). Comparable switching times of 8 s and a coloration efficiency of up to 116 cm2 C-1 are achieved.

Metal oxide-based gas sensor technology is promising due to their practical applications in toxic and hazardous gas detection. Orthorhombic α-MoO3 is a planar metal oxide with a unique layered structure, which can be obtained in a two-dimensional (2D) form. In the 2D form, the larger surface area-to-volume ratio of the material facilitates significantly higher interaction with gas molecules while exhibiting exceptional transport properties. The presence of oxygen vacancies results in nonstoichiometric MoO3 (MoO3-x), which further enhances the charge carrier mobility. Here, we study dual gas sensing characteristics and mechanism of 2D α-MoO3-x. Herein, conductometric dual gas sensors based on chemical vapor deposited 2D α-MoO3-x are developed and demonstrated. A facile transfer process is established to integrate the material into any arbitrary substrate. The sensors show high selectivity toward NO2 and H2S gases with response and recovery rates of 295.0 and 276.0 kΩ/s toward NO2 and 28.5 and 48.0 kΩ/s toward H2S, respectively. These gas sensors also show excellent cyclic endurance with a variation in ΔR ∼ 112 ± 1.64 and 19.5 ± 1.13 MΩ for NO2 and H2S, respectively. As such, this work presents the viability of planar 2D α-MoO3-x as a dual selective gas sensor.

Failure to classify audio data with high efficiency causes major setbacks in audio processing, voice recognition, and noise cancellation. To find the best possible neural network models for audio classification, this article shows the steps in the experiments performed in the newly designed CF Model and CF Clean Model in both CNN and RNN and compares the results with some existing models such as DCNN and PiczakCNN. To get a clear view of the consistency of the results, three different datasets have been experimented on, which are UrbanSound8k, FSDKaggle2018 and ESC-50. It also performs best in terms of the training and testing dataset based on accuracy and loss percentage. Finally, this article shows influences about the envelope function, normalization, segmentation, regularization techniques, and dropout layers in the overall progress.

Highly confined and low-loss polaritons are known to propagate isotropically over graphene and hexagonal boron nitride in the plane, leaving limited degrees of freedom in manipulating light at the nanoscale. The emerging family of biaxial van der Waals materials, such as α-MoO3 and V2O5, support exotic polariton propagation, as their auxiliary optical axis is in the plane. Here, exploiting this strong in-plane anisotropy, we report edge-tailored hyperbolic polaritons in patterned α-MoO3 nanocavities via real-space nanoimaging. We find that the angle between the edge orientation and the crystallographic direction significantly affects the optical response, and can serve as a key tuning parameter in tailoring the polaritonic patterns. By shaping α-MoO3 nanocavities with different geometries, we observe edge-oriented and steerable hyperbolic polaritons as well as forbidden zones where the polaritons detour. The lifetime and figure of merit of the hyperbolic polaritons can be regulated by the edge aspect ratio of nanocavity., The possibility to manipulate the propagation of polaritons is limited by the isotropy of 2D materials like graphene and hexagonal boron nitride. Here, the authors exploit the anisotropy of α-MoO3 and study edge tailored hyperbolic polariton manipulation in α-MoO3 nanocavities via real space nanoimaging.

This paper endeavors to develop a new background estimation model for foreground segmentation using traditional background subtraction technique. Particularly, incorporation of luminance- and pollution-controlling parameters enables the model to address illumination variation and tail backs from vehicles, respectively. To classify each foreground pixel, a new heuristic dynamic threshold-difference function is proposed for determining individual threshold. Moreover, newly presented Positive Negative Segmentation technique removes shadow considering its physical characteristics from the foreground. After shadow correction, impulse flow waves and aggregated pictorial speed are computed accordingly. Impulse flow waves are eventually rectified and cumulated into actual flow. Pictorial speed is converted into actual speed using calibration equation considering perspective error. To facilitate video-based traffic measurement, a user-friendly tool PARTS (Pixel-Based Heterogeneous Traffic Measurement) is developed which incorporates the whole system. The data collected at different roadway locations are compared with that generated by the tool. It shows 90 and 97% correlations in measuring flow and speed, respectively.

The human skin is the largest sensory organ, made up of complex sensors that detect noxious stimuli to rapidly send warning signals to the central nervous system to initiate a motor response. It is complex to mimic key skin features using existing tactile sensors, and there exists no somatosensor that responds to real stimuli of pressure, temperature, and touch. Herein, three critical skin receptors created by realizing integrated electronic systems that mimic the feedback response of somatosensors are experimentally demonstrated. Fully functional Pacinian corpuscles, thermoreceptors, and nociceptors are realized using a combination of stretchable pressure sensors, phase‐change oxide thin films, and threshold‐based resistive switching (memristor) memory elements. The ability to detect and respond to pressure, temperature, and pain stimuli above a threshold with real‐life performance characteristics is demonstrated with explanation of underlying mechanisms. The ability to design and realize artificial skin receptors enables replacement of affected human skin regions, augment skin sensitivity for agile applications in defense and sports, and drive advancements in intelligent robotics.

Background A number of barriers prevent community pharmacists (CPs) from impacting public health (PH) outcomes. Social media (SM) and mobile health apps (MH apps) may offer ways to help the public make positive health decisions. Objectives To evaluate CP perceptions of their role in PH and the use of SM and MH apps in this regard. Methods This was a mixed method study using a cross-sectional survey and follow-up interviews. The survey covered: CPs role in PH; CP use of SM; CP use of MH apps; non-identifiable demographic information. Following ethical approval and piloting, responses were collected on paper and online. The study population was CPs in Greater London, UK (n = 2931). A minimum sample size of 340 was calculated (95% confidence interval/5% margin of error). To achieve this, 596 surveys were distributed. Responses (n = 257) were analysed using descriptive statistics. Twenty-five respondents were willing to take part in follow-up one-to-one interviews. Twenty interviews were completed as data saturation was achieved after the 14th. Interviews were transcribed and analysed using framework methodology as described by Ritchie and Spencer in 1994. Results Survey response rate was 43%. Respondents represented English CPs in terms of age but males and non-whites were over-represented. The majority of CPs accessed SM and MH apps for personal use but did not recommend these in a professional capacity due to lack of awareness and confidentiality/liability concerns. Most would promote an SM health page (78.6%) or MH app (83.7%) if maintained by healthcare professionals (HCPs). Under 35s were more positive about these tools in PH. Two interview themes emerged: The role of CPs in PH; Concerns and opportunities for the use of technology in PH. Conclusions Most CPs, particularly those under 30, were positive about the use of SM and MH apps in PH. Training on the use of such tools among the pharmacy team, and an awareness of the availability of evidence-based apps will ensure their wider adoption.

© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Few-layer black phosphorous (BP) has emerged as a promising candidate for next-generation nanophotonic and nanoelectronic devices. However, rapid ambient degradation of mechanically exfoliated BP poses challenges in its practical deployment in scalable devices. To date, the strategies employed to protect BP have relied upon preventing its exposure to atmospheric conditions. Here, an approach that allows this sensitive material to remain stable without requiring its isolation from the ambient environment is reported. The method draws inspiration from the unique ability of biological systems to avoid photo-oxidative damage caused by reactive oxygen species. Since BP undergoes similar photo-oxidative degradation, imidazolium-based ionic liquids are employed as quenchers of these damaging species on the BP surface. This chemical sequestration strategy allows BP to remain stable for over 13 weeks, while retaining its key electronic characteristics. This study opens opportunities to practically implement BP and other environmentally sensitive 2D materials for electronic applications.

Two-dimensional MoO3 is a versatile planar material, whose properties can be readily tuned, rendering it anywhere from a wide bandgap semiconductor to semi-metallic. This makes it a desirable candidate for a wide range of applications. However, to utilise its full potential, a repeatable process to produce high-quality two-dimensional (2D) crystals is yet to be reported. Here, we report a wet chemical etching process to controllably thin down bulk crystals of MoO3. This process does not result in any structural or compositional changes, while retaining the desirable intrinsic electronic properties of the material. Field effect transistors based on post-etched crystals exhibit switching ratios of over three orders of magnitude. As such, the proposed thinning process opens pathways to exploit the exotic properties of planar MoO3 to create versatile 2D systems.