Seeing pressure in color based on integration of highly sensitive pressure sensor and emission tunable light emitting diode.

We demonstrate a highly sensitive, low-cost, environmental-friendly pressure sensor derived from a wool-based pressure sensor with wide pressure sensing range using wool bricks embedded with a Ag nano-wires. The easy fabrication and light weight allow portable and wearable device applications. Wth the integration of a light-emitting diode possessing multi-wavelength emission, we illustrate a hybrid multi-functional LED-integrated pressure sensor that is able to convert different applied pressures to light emission with different wavelengths. Due to the high sensitivity of the pressure sensor, the demonstration of acoustic signal detection has also been presented using sound of a metronome and a speaker playing a song. This multi-functional pressure sensor can be implemented to technologies such as smart lighting, health care, visible light communication (VLC), and other internet of things (IoT) applications.

Stretchable Fluorescent Polyfluorene/Acrylonitrile Butadiene Rubber Blend Electrospun Fibers through Physical Interaction and Geometrical Confinement.

Stretchable light-emitting polymers are important for wearable electronics; however, the development of intrinsic stretchable light-emitting materials with great performance under large applied strain is the most critical challenge. Herein, this study demonstrates the fabrication of stretchable fluorescent poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctyl-fluorene)]/acrylonitrile butadiene rubber (PFN/NBR) blend nanofibers using the uniaxial electrospinning technique. The physical interaction of PFN with NBR and the geometrical confinement of nanofibers are employed to reduce PFN aggregation, leading to the high photoluminescence quantum yield of 35.7%. Such fiber mat film shows stable blue emission at the 50% strain for 200 stretching/release cycles, which has potential applications in smart textiles.

Bio-Based Transparent Conductive Film Consisting of Polyethylene Furanoate and Silver Nanowires for Flexible Optoelectronic Devices.

Exploiting biomass has raised great interest as an alternative to the fossil resources for environmental protection. In this respect, polyethylene furanoate (PEF), one of the bio-based polyesters, thus reveals a great potential to replace the commonly used polyethylene terephthalate (PET) on account of its better mechanical, gas barrier, and thermal properties. Herein, a bio-based, flexible, conductive film is successfully developed by coupling a PEF plastic substrate with silver nanowires (Ag NWs). Besides the appealing advantage of renewable biomass, PEF also exhibits a good transparency around 90% in the visible wavelength range, and its constituent polar furan moiety is revealed to enable an intense interaction with Ag NWs to largely enhance the adhesion of Ag NWs grown above, as exemplified by the superior bending and peeling durability than the currently prevailing PET substrate. Finally, the efficiency of conductive PEF/Ag NWs film in fabricating efficient flexible organic thin-film transistor and organic photovoltaic (OPV) is demonstrated. The OPV device achieves a power conversion efficiency of 6.7%, which is superior to the device based on ITO/PEN device, manifesting the promising merit of the bio-based PEF for flexible electronic applications.

Scalable Wet Deposition of Zeolite AEI with a High Degree of Preferred Crystal Orientation.

Producing zeolite films with controlled preferred orientation on an industrial scale is a long-standing challenge. Herein we report on a scalable approach to the direct wet deposition of zeolite thin films and membranes while maintaining a high degree of control over the preferred crystal orientation. As a proof of concept, thin films comprising aluminophosphate zeolite AEI were cast on silicon wafer or porous alumina substrates. Electrical properties and separation performance of the zeolite thin films/membranes were engineered through controlling degree of preferred crystal orientation.

Relationships between the solution and solid-state properties of solution-cast low-k silica thin films.

This paper reports on the fabrication of low-k (amorphous) silica thin films cast from solutions without and with two different types of surfactants (TWEEN® 80 and Triton™ X-100) to elucidate the relationships between the structural/morphological features of the casting solutions and the physical properties of the resulting thin films. Cryogenic transmission microscopy (cryo-TEM), static/dynamic light scattering (SLS/DLS), and small-angle X-ray scattering (SAXS) revealed contrasting colloidal dispersion states and phase behavior among the three casting solutions. Casting solution with the Triton™ X-100 surfactant produced stable (>90 days) nanoparticles with good dispersion in solution (mean particle size ∼10 nm) as well as good mesopore volume (characterized by nitrogen physisorption) in powder and thin films of high mechanical strength (characterized by the nanoindentation test). The longer main chain and bulkier side units of the TWEEN® 80 surfactant led to stable micelle-nanoparticle coexisting dispersion, which resulted in the highest mesopore volume in powder and thin films with the lowest dielectric constant (∼3) among the samples in this study. The casting solution without the surfactant failed to produce a stabilized solution or thin films of acceptable uniformity. These findings demonstrate the possibility of fine-tuning low-k silica film properties by controlling the colloidal state of casting solutions.

Survival comparison of daily home hemodialysis vs. conventional in the nursing home setting.

Nursing home patients on dialysis are higher-acuity compared to the broader end-stage renal disease population, and historically have poor outcomes. The objective of this epidemiological study was to compare outcomes in ESRD patients in the nursing home setting treated with daily home hemodialysis versus conventional three-day-a-week hemodialysis. Health status was evaluated for 3,919 patients (n=3391 conventional, n=528 daily home dialysis; April 2007 to June 2013 for conventional; April 2011 to June 2013 for daily home hemodialysis). Analyses included monthly mortality rates, Kaplan-Meier survival analysis, and laboratory values. Results showed monthly mortality rates were consistently lower in the daily home hemodialysis population over the same time period vs. conventional dialysis care. In the incident three months of treatment, annualized monthly mortality rates were 70%, 72%, and 64% in the conventional dialysis population vs. 50%, 24%, and 17% in the daily home population. Patients treated with daily home dialysis had generally similar or higher albumin and hemoglobin values and lower ferritin values over the same time period. Patients treated with daily home hemodialysis had lower monthly mortality rates and generally improved health status compared to patients treated with conventional dialysis. The results of this study are provocative and should be evaluated in a prospective study.

Understanding polymorphism in organic semiconductor thin films through nanoconfinement.

Understanding crystal polymorphism is a long-standing challenge relevant to many fields, such as pharmaceuticals, organic semiconductors, pigments, food, and explosives. Controlling polymorphism of organic semiconductors (OSCs) in thin films is particularly important given that such films form the active layer in most organic electronics devices and that dramatic changes in the electronic properties can be induced even by small changes in the molecular packing. However, there are very few polymorphic OSCs for which the structure-property relationships have been elucidated so far. The major challenges lie in the transient nature of metastable forms and the preparation of phase-pure, highly crystalline thin films for resolving the crystal structures and evaluating the charge transport properties. Here we demonstrate that the nanoconfinement effect combined with the flow-enhanced crystal engineering technique is a powerful and likely material-agnostic method to identify existing polymorphs in OSC materials and to prepare the individual pure forms in thin films at ambient conditions. With this method we prepared high quality crystal polymorphs and resolved crystal structures of 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene), including a new polymorph discovered via in situ grazing incidence X-ray diffraction and confirmed by molecular mechanic simulations. We further correlated molecular packing with charge transport properties using quantum chemical calculations and charge carrier mobility measurements. In addition, we applied our methodology to a [1]benzothieno[3,2-b][1]1benzothiophene (BTBT) derivative and successfully stabilized its metastable form.

Health outcomes in nursing home patients on dialysis.

Nursing home patients on dialysis are higher-acuity compared to the broader ESRD population. The objective of this study was to evaluate health status and outcomes in patients on hemodialysis in a nursing home setting. Health status was evaluated for 3,943 patients between April 2007 and June 2013. Patients had poor initial health status, with an incident first month annualized mortality rate of 70%, mean serum albumin of 3.2 g/dL, and mean hemoglobin of 10.15 g/dL. Improvements were noted during months 4-12, with annualized mortality rates of 30%, serum albumin of 3.6 g/dL, and mean hemoglobin of 10.8 g/dL. Patient outcomes also improved year-over-year. These study results demonstrated poor initial health status, but improvements in patient outcomes over time when dialysis is provided in a nursing home setting.

Computational Investigation of the Potential and Limitations of Machine Learning with Neural Network Circuits Based on Synaptic Transistors.

Synaptic transistors have been proposed to implement neuron activation functions of neural networks (NNs). While promising to enable compact, fast, inexpensive, and energy-efficient dedicated NN circuits, they also have limitations compared to digital NNs (realized as codes for digital processors), including shape choices of the activation function using particular types of transistor implementation, and instabilities due to noise and other factors present in analog circuits. We present a computational study of the effects of these factors on NN performance and find that, while accuracy competitive with traditional NNs can be realized for many applications, there is high sensitivity to the instability in the shape of the activation function, suggesting that, when highly accurate NNs are required, high-precision circuitry should be developed beyond what has been reported for synaptic transistors to date.

Rationally Improved Surface Charge Density of Triboelectric Nanogenerator with TiO2-MXene/Polystyrene Nanofiber Charge Trapping Layer for Biomechanical Sensing and Wound Healing Application.

Triboelectric nanogenerators (TENGs) have become reliable green energy harvesters by converting biomechanical motions into electricity. However, the inevitable charge leakage and poor electric field (EF) of conventional TENG result in inferior tribo-charge density on the active layer. In this paper, TiO2-MXene incorporated polystyrene (PS) nanofiber membrane (PTMx NFM) charge trapping interlayer is introduced into single electrode mode TENG (S-TENG) to prevent electron loss at the electrode interface. Surprisingly, this charge-trapping mechanism augments the surface charge density and electric output performance of TENGs. Polyvinylidene difluoride (PVDF) mixed polyurethane (PU) NFM is used as tribo-active layer, which improves the crystallinity and mechanical property of PVDF to prevent delamination during long cycle tests. Herein, the effect of this double-layer capacitive model is explained experimentally and theoretically. With optimization of the PTMx interlayer thickness, S-TENG exhibits a maximum open-circuit voltage of (280 V), short-circuit current of (20 µA) transfer charge of (120 nC), and power density of (25.2 µW cm-2). Then, this energy is utilized to charge electrical appliances. In addition, the influence of AC/DC EF simulation in wound healing management (vitro L929 cell migration, vivo tissue regeneration) is also investigated by changing the polarity of trans-epithelial potential (TEP) distribution in the wounded area.

Age-related differences in clinical outcomes for acute asthma in the United States, 2006-2008.

BACKGROUND: Little is known about the effect of age on acute asthma outcomes. OBJECTIVE: We sought to investigate age-related differences in the emergency department (ED) presentation and clinical outcomes for patients with acute asthma. METHODS: We analyzed the 2006-2008 Nationwide Emergency Department Sample, the largest, all-payer, US ED and inpatient database. ED visits for acute asthma were identified with a principal diagnosis of International Classification of Disease, ninth revision, Clinical Modification code 493.xx. Patients were divided into 3 age groups: children (<18 years), younger adults (18-54 years), and older adults (≥55 years). The outcome measures were in-hospital all-cause mortality, near-fatal asthma-related events (noninvasive or mechanical ventilation), hospital charges, admission rates, and hospital length of stay. RESULTS: There were an estimated 1,813,000 visits annually for acute asthma from approximately 4,700 EDs. The estimated overall annual number of in-hospital asthma-related deaths was 1,144 (0.06%); 101 died in the ED, and 1,043 died as inpatients. By age group, there were 37 asthma-related deaths per year in children, 204 in younger adults, and 903 in older adults. Compared with younger adults, older adults had higher mortality, had higher rates of near-fatal asthma-related events, had higher hospital charges, were more likely to be hospitalized, and had a longer hospital length of stay (P < .001 for all). After adjusting for comorbidities, older asthmatic patients had a 5-fold increased risk of overall mortality (adjusted odds ratio, 5.2; 95% CI, 4.0-6.9), compared with younger adults. CONCLUSIONS: Older adults with acute asthma have a substantial burden of morbidity and mortality. With the US population aging, there is an urgent need for targeted interventions for this high-risk population.

Antipsychotic drug trifluoperazine as a potential therapeutic agent against nasopharyngeal carcinoma.

BACKGROUND: Trifluoperazine (TFP) is a typical antipsychotic primarily used to treat schizophrenia. In this study, we aimed to evaluate whether TFP can be used as a therapeutic agent against nasopharyngeal carcinoma (NPC) and identify its underlying molecular mechanisms. METHODS: We used NPC-TW01, TW03, TW04, and BM to assess the anticancer effects of TFP by using cytotoxicity, wound healing, colony formation, and cell invasion assays. An in vivo animal study was conducted. RNA sequencing combined with Ingenuity Pathways Analysis was performed to identify the mechanism by which TFP influences NPC cells. RESULTS: Our data revealed that TFP decreased NPC cell viability in a dose-dependent manner. The invasion and migration of NPC tumor cells were inhibited by TFP. An in vivo study also demonstrated the anticancer effects of TFP. RNA sequencing revealed several anticancer molecular mechanisms following TFP administration. CONCLUSIONS: The antipsychotic drug TFP could be a potential therapeutic regimen for NPC treatment.

A Hemispherical Image Sensor Array Fabricated with Organic Photomemory Transistors.

Hemispherical image sensors simplify lens designs, reduce optical aberrations, and improve image resolution for compact wide-field-of-view cameras. To achieve hemispherical image sensors, organic materials are promising candidates due to the following advantages: tunability of optoelectronic/spectral response and low-temperature low-cost processes. Here, a photolithographic process is developed to prepare a hemispherical image sensor array using organic thin film photomemory transistors with a density of 308 pixels per square centimeter. This design includes only one photomemory transistor as a single active pixel, in contrast to the conventional pixel architecture, consisting of select/readout/reset transistors and a photodiode. The organic photomemory transistor, comprising light-sensitive organic semiconductor and charge-trapping dielectric, is able to achieve a linear photoresponse (light intensity range, from 1 to 50 W m-2 ), along with a responsivity as high as 1.6 A W-1 (wavelength = 465 nm) for a dark current of 0.24 A m-2 (drain voltage = -1.5 V). These observed values represent the best responsivity for similar dark currents among all the reported hemispherical image sensor arrays to date. A transfer method was further developed that does not damage organic materials for hemispherical organic photomemory transistor arrays. These developed techniques are scalable and are amenable for other high-resolution 3D organic semiconductor devices.

Human Skin-Inspired Electrospun Patterned Robust Strain-Insensitive Pressure Sensors and Wearable Flexible Light-Emitting Diodes.

Wearable skin-inspired electronic skins present remarkable outgrowth in recent years because their promising comfort device integration, lightweight, and mechanically robust durable characteristics led to significant progresses in wearable sensors and optoelectronics. Wearable electronic devices demand real-time applicability and factors such as complex fabrication steps, manufacturing cost, and reliable and durable performances, severely limiting the utilization. Herein, we nominate a scalable solution-processable electrospun patterned candidate capable of forming ultralong mechanically robust nano-microdimensional fibers with higher uniformity. Nanofibrous patterned substrates present surface energy and silver nanoparticle crystallization shifts, contributing to strain-sensitive and -insensitive conductive electrodes (10 000 cycles of 50% strain). Synergistic robust stress releasing and durable electromechanical behavior engenders stretchable durable health sensors, strain-insensitive pressure sensors (sensitivity of ∼83 kPa-1 and 5000 durable cycles), robust alternating current electroluminescent displays, and flexible organic light-emitting diodes (20% improved luminescence and 300 flex endurance of 2 mm bend radius).

Smartphone-based artificial intelligence using a transfer learning algorithm for the detection and diagnosis of middle ear diseases: A retrospective deep learning study.

Background: Middle ear diseases such as otitis media and middle ear effusion, for which diagnoses are often delayed or misdiagnosed, are among the most common issues faced by clinicians providing primary care for children and adolescents. Artificial intelligence (AI) has the potential to assist clinicians in the detection and diagnosis of middle ear diseases through imaging. Methods: Otoendoscopic images obtained by otolaryngologists from Taipei Veterans General Hospital in Taiwan between Jany 1, 2011 to Dec 31, 2019 were collected retrospectively and de-identified. The images were entered into convolutional neural network (CNN) training models after data pre-processing, augmentation and splitting. To differentiate sophisticated middle ear diseases, nine CNN-based models were constructed to recognize middle ear diseases. The best-performing models were chosen and ensembled in a small CNN for mobile device use. The pretrained model was converted into the smartphone-based program, and the utility was evaluated in terms of detecting and classifying ten middle ear diseases based on otoendoscopic images. A class activation map (CAM) was also used to identify key features for CNN classification. The performance of each classifier was determined by its accuracy, precision, recall, and F1-score. Findings: A total of 2820 clinical eardrum images were collected for model training. The programme achieved a high detection accuracy for binary outcomes (pass/refer) of otoendoscopic images and ten different disease categories, with an accuracy reaching 98.0% after model optimisation. Furthermore, the application presented a smooth recognition process and a user-friendly interface and demonstrated excellent performance, with an accuracy of 97.6%. A fifty-question questionnaire related to middle ear diseases was designed for practitioners with different levels of clinical experience. The AI-empowered mobile algorithm's detection accuracy was generally superior to that of general physicians, resident doctors, and otolaryngology specialists (36.0%, 80.0% and 90.0%, respectively). Our results show that the proposed method provides sufficient treatment recommendations that are comparable to those of specialists. Interpretation: We developed a deep learning model that can detect and classify middle ear diseases. The use of smartphone-based point-of-care diagnostic devices with AI-empowered automated classification can provide real-world smart medical solutions for the diagnosis of middle ear diseases and telemedicine. Funding: This study was supported by grants from the Ministry of Science and Technology (MOST110-2622-8-075-001, MOST110-2320-B-075-004-MY3, MOST-110-2634-F-A49 -005, MOST110-2745-B-075A-001A and MOST110-2221-E-075-005), Veterans General Hospitals and University System of Taiwan Joint Research Program (VGHUST111-G6-11-2, VGHUST111c-140), and Taipei Veterans General Hospital (V111E-002-3).

Tuning Ambipolarity of the Conjugated Polymer Channel Layers of Floating-Gate Free Transistors: From Volatile Memories to Artificial Synapses.

Three-terminal synaptic transistor has drawn significant research interests for neuromorphic computation due to its advantage of facile device integrability. Lately, bulk-heterojunction-based synaptic transistors with bipolar modulation are proposed to exempt the use of an additional floating gate. However, the actual correlation between the channel's ambipolarity, memory characteristic, and synaptic behavior for a floating-gate free transistor has not been investigated yet. Herein, by studying five diketopyrrolopyrrole-benzotriazole dual-acceptor random conjugated polymers, a clear correlation among the hole/electron ratio, the memory retention characteristic, and the synaptic behavior for the polymer channel layer in a floating-gate free transistor is described. It reveals that the polymers with balanced ambipolarity possess better charge trapping capabilities and larger memory windows; however, the high ambipolarity results in higher volatility of the memory characteristics, namely poor memory retention capability. In contrast, the polymer with a reduced ambipolarity possesses an enhanced memory retention capability despite showing a reduced memory window. It is further manifested that this enhanced charge retention capability enables the device to present artificial synaptic characteristics. The results highlight the importance of the channel's ambipolarity of floating-gate free transistors on the resultant volatile memory characteristics and synaptic behaviors.

Solution-shear-processed quaterrylene diimide thin-film transistors prepared by pressure-assisted thermal cleavage of swallow tails.

A scalable synthesis of swallow-tailed quaterrylene diimides (STQDIs) and a method for the solution processing of sparingly soluble quaterrylene diimide (QDI) thin films are described. The pressure-assisted thermal cleavage of swallow tails yields crystalline QDI layers with electron mobility up to 0.088 cm(2) V(-1) s(-1). The developed method opens up a new route toward the solution processing of higher rylene diimides with poor solubility.

Dopamine-Initiated Photopolymerization for a Versatile Catechol-Functionalized Hydrogel.

Biomimetic catechol-functionalized hydrogels have attracted substantial attention due to their potential in a variety of biomedical applications, such as tissue repair and regeneration, drug delivery, and antimicrobial and antifouling applications. In this study, a one-pot strategy for fabrication of functional catecholic hydrogels using dopamine as a photoinitiator was developed. Under UV irradiation in an acidic solution, dopamine generates free radicals, likely semiquinone radicals, to trigger the addition polymerization, following pseudo-first-order kinetics. The dopamine-initiated photopolymerization provides a straightforward and facile approach and, in addition, prevents the undesirable oxidation to catecholic groups. Superhydrophilic sulfobetaine methacrylate (SBMA) was applied for developing biocompatible hydrogels. 1H nuclear magnetic resonance, UV-vis spectroscopy, gel permeation chromatography, and rheological studies were conducted to explore the polymerization mechanism and optimal experimental conditions in terms of pH, UV doses, and the concentration of dopamine. The unique properties of the resultant catechol-functionalized pSBMA hydrogels were demonstrated by enhanced mechanical properties through metal-catechol complexation, self-healing and injectable capability, high adhesiveness, and fouling resistance. Consequently, the synthetic strategy to design catecholic hydrogels can leverage the use of dopamine in a variety of applications.

Solution-Processable Anion-doped Conjugated Polymer for Nonvolatile Organic Transistor Memory with Synaptic Behaviors.

Brain-inspired synaptic transistors have been considered as a promising device for next-generation electronics. To mimic the behavior of a biological synapse, both data processing and nonvolatile memory capability are simultaneously required for a single electronic device. In this work, a simple approach to realize a synaptic transistor with improved memory characteristics is demonstrated by doping an ionic additive, tetrabutylammonium perchlorate (TBAP), into an active polymer semiconductor without using any extra charge storage layer. TBAP doping is first revealed to improve the memory window of a derived transistor memory device from 19 to 32 V (∼68% enhancement) with an on/off current ratio over 103 at VG = -10 V. Through morphological analysis and theoretical calculations, it is revealed that the association of anion with polymers enhances the charge retention capability of the polymer and facilitates the interchain interactions to result in improved memory characteristics. More critically, the doped device is shown to successfully mimic the synaptic behaviors, such as paired-pulse facilitation (PPF), excitatory and inhibitory postsynaptic currents, and spike-rate dependent plasticity. Notably, the TBAP-doped device is shown to deliver a PPF index of up to 204% in contrast to the negligible value of an undoped device. This study describes a novel approach to prepare a synaptic transistor by doping conjugated polymers, which can promote the future development of artificial neuromorphic systems.

Self-Powered, Self-Healed, and Shape-Adaptive Ultraviolet Photodetectors.

The emergence of self-healing devices in recent years has drawn a great amount of attention in both academics and industry. Self-healed devices can autonomically restore a rupture as unexpected destruction occurs, which can efficiently prolong the life span of the devices; hence, they have an enhanced durability and decreased replacement cost. As a result, integration of wearable devices with self-healed electronics has become an indispensable issue in smart wearable devices. In this study, we present the first self-powered, self-healed, and wearable ultraviolet (UV) photodetector based on the integration of agarose/poly(vinyl alcohol) (PVA) double network (DN) hydrogels, which have the advantages of good mechanical strength, self-healing ability, and tolerability of multiple types of damage. With the integration of a DN hydrogel substrate, the photodetector enables 90% of the initial efficiency to be restored after five healing cycles, and each rapid healing time is suppressed to only 10 s. The proposed device has several merits, including having an all spray coating, self-sustainability, biocompatibility, good sensitivity, mechanical flexibility, and an outstanding healing ability, which are all essential to build smart electronic systems. The unprecedented self-healed photodetector expands the future scope of electronic skin design, and it also offers a new platform for the development of next-generation wearable electronics.