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1.
Adv Mater ; : e2004401, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33169447

RESUMO

Solar evaporation through a photothermal porous material provides a feasible and sustainable method for water remediation. Several photothermal materials have been developed to enhance solar evaporation efficiency. However, a critical limitation of current photothermal materials is their inability to separate water from the volatile organic compounds (VOCs) present in wastewater. Here, a microstructured ultrathin polymeric membrane that enables freshwater separation from VOC pollutants by solar evaporation with a VOC removal rate of 90%, is reported. The different solution-diffusion behaviors of water and VOCs with polymeric membranes facilitate their separation. Moreover, owing to increased light absorption, enlarged liquid-air interface, and shortened mass transfer distance, the microstructured and ultrathin configuration of the membrane helps to balance the tradeoff between permeation selectivity and water production capacity. The membrane is not only effective for evaporation of simulated volatile pollutants in a prototype, but can also intercept complex volatile organic contaminants in natural water sources and produce water that meets drinking-water standards. With practical demonstration and satisfactory purification performance, this work paves the way for practical application of solar evaporation for effective water remediation.

2.
Nat Commun ; 11(1): 4602, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929071

RESUMO

Human behaviors are extremely sophisticated, relying on the adaptive, plastic and event-driven network of sensory neurons. Such neuronal system analyzes multiple sensory cues efficiently to establish accurate depiction of the environment. Here, we develop a bimodal artificial sensory neuron to implement the sensory fusion processes. Such a bimodal artificial sensory neuron collects optic and pressure information from the photodetector and pressure sensors respectively, transmits the bimodal information through an ionic cable, and integrates them into post-synaptic currents by a synaptic transistor. The sensory neuron can be excited in multiple levels by synchronizing the two sensory cues, which enables the manipulating of skeletal myotubes and a robotic hand. Furthermore, enhanced recognition capability achieved on fused visual/haptic cues is confirmed by simulation of a multi-transparency pattern recognition task. Our biomimetic design has the potential to advance technologies in cyborg and neuromorphic systems by endowing them with supramodal perceptual capabilities.


Assuntos
Células Receptoras Sensoriais/fisiologia , Tato/fisiologia , Visão Ocular/fisiologia , Animais , Linhagem Celular , Eletrodos , Humanos , Camundongos , Movimento (Física) , Nanotubos de Carbono/química , Reconhecimento Automatizado de Padrão
3.
Adv Mater ; : e2003014, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32930454

RESUMO

Skin is the largest organ, with the functionalities of protection, regulation, and sensation. The emulation of human skin via flexible and stretchable electronics gives rise to electronic skin (e-skin), which has realized artificial sensation and other functions that cannot be achieved by conventional electronics. To date, tremendous progress has been made in data acquisition and transmission for e-skin systems, while the implementation of perception within systems, that is, sensory data processing, is still in its infancy. Integrating the perception functionality into a flexible and stretchable sensing system, namely artificial skin perception, is critical to endow current e-skin systems with higher intelligence. Here, recent progress in the design and fabrication of artificial skin perception devices and systems is summarized, and challenges and prospects are discussed. The strategies for implementing artificial skin perception utilize either conventional silicon-based circuits or novel flexible computing devices such as memristive devices and synaptic transistors, which enable artificial skin to surpass human skin, with a distributed, low-latency, and energy-efficient information-processing ability. In future, artificial skin perception would be a new enabling technology to construct next-generation intelligent electronic devices and systems for advanced applications, such as robotic surgery, rehabilitation, and prosthetics.

4.
Adv Mater ; 32(37): e2001903, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32743815

RESUMO

Flexible electronics have witnessed exciting progress in academia over the past decade, but most of the research outcomes have yet to be translated into products or gain much market share. For mass production and commercialization, industrial adoption of newly developed functional materials and fabrication techniques is a prerequisite. However, due to the disparate features of academic laboratories and industrial plants, translating materials and manufacturing technologies from labs to fabs is notoriously difficult. Therefore, herein, key challenges in the materials manufacturing of flexible electronics are identified and discussed for its lab-to-fab translation, along the four stages in product manufacturing: design, materials supply, processing, and integration. Perspectives on industry-oriented strategies to overcome some of these obstacles are also proposed. Priorities for action are outlined, including standardization, iteration between basic and applied research, and adoption of smart manufacturing. With concerted efforts from academia and industry, flexible electronics will bring a bigger impact to society as promised.

5.
Stem Cell Res Ther ; 11(1): 114, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32169113

RESUMO

BACKGROUND: Long noncoding RNAs (lncRNAs) play an important role in the multiple differentiations of mesenchymal stem cells (MSCs). However, few studies have focused on the regulatory mechanism of lncRNAs in the odontogenic differentiation of human dental pulp stem cells (hDPSCs). METHODS: hDPSCs were induced to differentiate into odontoblasts in vitro, and the expression profiles of lncRNAs, microRNAs (miRNAs), and messenger RNAs (mRNAs) in differentiated and undifferentiated cells were obtained by microarray. Bioinformatics analyses including Gene Ontology (GO) analysis, pathway analysis, and binding site prediction were performed for functional annotation of lncRNA. miRNA/odontogenesis-related gene networks and lncRNA-associated ceRNA networks were constructed. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) was used to verify the expression of selected genes. RNA fluorescence in situ hybridization (FISH), qRT-PCR, and western blot analysis were used to explore the location and function of lncRNA-G043225. Dual-luciferase reporter assay was performed to confirm the binding sites of miR-588 with G043225 and Fibrillin 1 (FBN1). RESULTS: We identified 132 lncRNAs, 114 miRNAs, and 172 mRNAs were differentially expressed. GO analysis demonstrated that regulation of the neurogenic locus notch homolog (Notch), Wnt, and epidermal growth factor receptor (ERBB) signaling pathways and activation of mitogen-activated protein kinase (MAPK) activity were related to odontogenic differentiation. Pathway analysis indicated that the most significant pathway was the forkhead box O (FoxO) signaling pathway, which is related to odontogenic differentiation. Two odontogenesis-related gene-centered lncRNA-associated ceRNA networks were successfully constructed. The qRT-PCR validation results were consistent with the microarray analysis. G043225 mainly locating in cytoplasm was proved to promote the odontogenic differentiation of hDPSCs via miR-588 and FBN1. CONCLUSION: This is the first study revealing lncRNA-associated ceRNA network during odontogenic differentiation of hDPSCs using microarray, and it could provide clues to explore the mechanism of action at the RNA-RNA level as well as novel treatments for dentin regeneration based on stem cells.

6.
Nanoscale ; 12(9): 5347-5352, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32100778

RESUMO

A CoCrFeNiMn high entropy alloy with a novel nanostructure consisting of ultrafine grains, TiO(C) nanoparticles and nanotwins has been fabricated. It achieves an ultrahigh tensile yield strength of 1507 MPa by coupling multiple strengthening mechanisms, including grain boundary strengthening, twin boundary strengthening, nanoparticle strengthening and dislocation strengthening. The work hardening ability is also improved by coupling the interactions of dislocations with nanoparticles and nanotwins during plastic deformation, leading to a good tensile ductility with a uniform elongation of 4.7%.

7.
Biomater Sci ; 8(3): 960-972, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31844849

RESUMO

On-demand controllable drug delivery systems enable the administration of precise dosages and thus have the potential to improve overall healthcare. In this work, a tough physical hydrogel is developed and studied for triggered burst release. Semicrystalline poly (vinyl alcohol) (PVA) is combined with ionic pectin (CaP) to form an interpenetrating network (PVA-CaP). The synergistic combination of crosslinking mechanisms resulted in a threefold improvement in tensile modulus and fracture energy over pristine PVA. As a result of the physical network, crosslink dissociation could be induced by heating. This trait is used as a trigger for burst release of a payload in PVA-CaP flexible substrates. Highly localized and on-demand burst release can be effectively achieved through the inclusion of electronic devices. Cell adhesion and viability tests show that the addition of pectin remarkably improves cell attachment ability and provides a favourable environment for cell proliferation. Implantation tests finally show the suitability of the material for implantation and its ability to conform with natural tissue. Such a system is envisioned for use as an implantable remote and controlled release device.


Assuntos
Preparações de Ação Retardada/química , Hidrogéis/química , Animais , Adesão Celular , Proliferação de Células , Sistemas de Liberação de Medicamentos , Feminino , Fibroblastos/citologia , Camundongos , Células NIH 3T3 , Pectinas/química , Álcool de Polivinil/química , Ratos , Ratos Sprague-Dawley , Resistência ao Cisalhamento , Resistência à Tração
8.
Biomater Sci ; 8(3): 763-775, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31808476

RESUMO

With the development of nanotechnology, nanomaterials are increasingly being applied in health fields, such as biomedicine, pharmaceuticals, and cosmetics. Concerns have therefore been raised over their toxicity and numerous studies have been carried out to assess their safety. Most studies on the toxicity and therapeutic mechanisms of nanomaterials have revealed the effects of nanomaterials on cells at the transcriptome and proteome levels. However, epigenetic modifications, for example DNA methylation, histone modification, and noncoding RNA expression induced by nanomaterials, which play an important role in the regulation of gene expression, have not received sufficient attention. In this review, we therefore state the importance of studying epigenetic effects induced by nanomaterials; then we review the progress of nanomaterial epigenetic research in the assessment of toxicity, therapeutic, and other mechanisms. We also clarify the possible study directions for future nanomaterial epigenetic research. Finally, we discuss the future development and challenges of nanomaterial epigenetics that must still be addressed. We hope to understand the potential toxicity of nanomaterials and clearly understand the therapeutic mechanism through a thorough investigation of nanomaterial epigenetics.


Assuntos
Epigênese Genética/efeitos dos fármacos , Nanoestruturas/toxicidade , Animais , Metilação de DNA/efeitos dos fármacos , Humanos , Nanotecnologia
9.
Adv Mater ; 31(35): e1903130, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31259453

RESUMO

Stretchable strain sensors have aroused great interest for their application in human activity recognition, health monitoring, and soft robotics. For various scenarios involving the application of different strain ranges, specific sensitivities need to be developed, due to a trade-off between sensor sensitivity and stretchability. Traditional stretchable strain sensors are developed based on conductive sensing materials and still lack the function of customizable sensitivity. A novel strategy of mechanocombinatorics is proposed to screen the sensor sensitivity based on mechanically heterogeneous substrates. Strain redistribution over substrates is optimized by mechanics and structure parameters, which gives rise to customizable sensitivity. As a proof of concept, a local illumination method is used to fabricate heterogeneous substrates with customizable mechanics and structure parameters. A library of mechanocombinatorial strain sensors is created for extracting the specific sensitivity. Thus, not only is an effective strategy for screening of sensor sensitivity demonstrated, but a contribution to the mechanocombinatorial strategy for personalized stretchable electronics is also made.

10.
Adv Mater ; 31(35): e1901360, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282042

RESUMO

Stretchable conductors are the basic units of advanced flexible electronic devices, such as skin-like sensors, stretchable batteries and soft actuators. Current fabrication strategies are mainly focused on the stretchability of the conductor with less emphasis on the huge mismatch of the conductive material and polymeric substrate, which results in stability issues during long-term use. Thermal-radiation-assisted metal encapsulation is reported to construct an interlocking layer between polydimethylsiloxane (PDMS) and gold by employing a semipolymerized PDMS substrate to encapsulate the gold clusters/atoms during thermal deposition. The stability of the stretchable conductor is significantly enhanced based on the interlocking effect of metal and polymer, with high interfacial adhesion (>2 MPa) and cyclic stability (>10 000 cycles). Also, the conductor exhibits superior properties such as high stretchability (>130%) and large active surface area (>5:1 effective surface area/geometrical area). It is noted that this method can be easily used to fabricate such a stretchable conductor in a wafer-scale format through a one-step process. As a proof of concept, both long-term implantation in an animal model to monitor intramuscular electric signals and on human skin for detection of biosignals are demonstrated. This design approach brings about a new perspective on the exploration of stretchable conductors for biomedical applications.

11.
J Hypertens ; 37(1): 187-196, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30015757

RESUMO

BACKGROUND: The associations between umbilical cord coiling, feto-placental vascular resistance and maternal blood pressure (BP) are not well understood. METHOD: We retrospectively analyzed 502 pregnant women suspected of hypertensive disorders in the third trimester from a hospital-based cohort, who underwent ambulatory BP monitoring and umbilical artery Doppler velocimetry examinations within 14 days before delivery. By applying quantile regression, a significant quantile-dependent positive association between umbilical cord coiling index and umbilical artery pulsatility index (UAPIMOM; converted to multiples of median) was observed from above 0.75th quantiles for each parameter. RESULTS: Using the cutoffs both at the 0.75th quantile to define high umbilical cord coiling (≥0.28 coils/cm) and high UAPIMOM (≥1.30), respectively, a graded increase in BP level was observed from patients with both low, either high and both high categories. Multivariate linear and quantile regression revealed that the high umbilical cord coiling/high UAPIMOM interaction was significantly correlated with night-time mean DBP level. Moreover, umbilical cord hypercoiling (≥0.3 coils/cm) was significantly correlated with night-time DBP with an average increase of ∼5 mmHg from the 0.05th to 0.70th quantiles and independently predicted the occurrence of severe (odds ratio 2.32, 95% confidence interval: 1.22-4.41) and early-onset (odds ratio 2.43, 95% confidence interval: 1.18-4.97) preeclampsia after adjusting for covariates. Further mediation analysis showed that elevated high UAPIMOM (≥1.30) could explain 11.4% of the umbilical cord hypercoiling → high night-time DBP association. CONCLUSION: Therefore, this retrospective study identifies excessive umbilical cord coiling, and its interaction with increased feto-placental vascular resistance, as novel risk factors for nocturnal BP elevation and preeclampsia.


Assuntos
Pré-Eclâmpsia/epidemiologia , Complicações na Gravidez , Cordão Umbilical/fisiopatologia , Pressão Sanguínea/fisiologia , Feminino , Humanos , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/fisiopatologia , Estudos Retrospectivos , Fatores de Risco
12.
Adv Mater ; 30(50): e1805468, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30306649

RESUMO

Traditional stretchable supercapacitors, possessing a thin electrode and a 2D shape, have limited areal specific areal capacitance and are incompatible with 3D wearables. To overcome the limitations of 2D stretchable supercapacitors, it is highly desirable to develop 3D stretchable supercapacitors with higher mass loading and customizable shapes. In this work, a new 3D stretchable supercapacitor inspired by a honeycomb lantern based on an expandable honeycomb composite electrode composed of polypyrrole/black-phosphorous oxide electrodeposited on carbon nanotube film is reported. The 3D stretchable supercapacitors possessing device-thickness-independent ion-transport path and stretchability can be crafted into customizable device thickness for enhancing the specific areal energy storage and integrability with wearables. Notably, a 1.0 cm thick rectangular-shaped supercapacitor shows enhanced specific areal capacitance of 7.34 F cm-2 , which is about 60 times higher than that of the original 2D supercapacitor (120 mF cm-2 ) at a similar discharge rate. The 3D supercapacitor can also maintain a capacitance ratio of 95% even under the reversible strain of 2000% after 10 000 stretch-and-release cycles, superior to state-of-the-art stretchable supercapacitors. The enhanced specific areal energy storage and the customizablility in shapes of the 3D stretchable supercapacitors show immense promise in a wide range of applications in stretchable and wearable electronics.

13.
Adv Mater ; 30(30): e1801870, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29882372

RESUMO

Fouling of polymeric membranes remains a major challenge for long-term operation of oily-water remediation. The common reclamation methods to recycle fouled membranes have the issues of either incomplete degradation of organic pollutants or damage to filter membranes. Here, a calcinable polymer membrane with effective reclamation after fouling is reported, which shows full recovery of the original oil/water separation efficiency. The membrane is made of polysulfonamide/polyacrylonitrile fibers by emulsion electrospinning, followed by hydrothermal decoration of TiO2 nanoparticles. The bonding structured fibrous membrane displays outstanding thermal stability in air (400 °C), strong acid/alkali resistance (at the pH range from 1 to 13), and robust tensile strength. As a result, the chemically fouled polymeric membrane can be easily reclaimed without decreasing in separation performance and mechanical properties by annealing treatment. As a proof-of-concept, the as-prepared membrane is integrated into a wastewater separation tank, which achieves a high water flux over 3000 L m-2 h-1 and oil rejection efficiency of 99.6% for various oil-in-water emulsions. The presented strategy on membrane fabrication is believed to be an effective remedy for membrane fouling, and should apply in a wider field of filtration industry.

14.
Adv Mater ; 30(5)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29226515

RESUMO

Fiber-shaped stretchable strain sensors with small testing areas can be directly woven into textiles. This paves the way for the design of integrated wearable devices capable of obtaining real-time mechanical feedback for various applications. However, for a simple fiber that undergoes uniform strain distribution during deformation, it is still a big challenge to obtain high sensitivity. Herein, a new strategy, surface strain redistribution, is reported to significantly enhance the sensitivity of fiber-shaped stretchable strain sensors. A new method of transient thermal curing is used to achieve the large-scale fabrication of modified elastic microfibers with intrinsic microbeads. The proposed strategy is independent of the active materials utilized and can be universally applied for various active materials. The strategy used here will shift the vision of the sensitivity enhancement method from the active materials design to the mechanical design of the elastic substrate, and the proposed strategy can also be applied to nonfiber-shaped stretchable strain sensors.

15.
Adv Mater ; 30(2)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29134702

RESUMO

Although some progress has been made on stretchable supercapacitors, traditional stretchable supercapacitors fabricated by predesigning structured electrodes for device assembling still lack the device-level editability and programmability. To adapt to wearable electronics with arbitrary configurations, it is highly desirable to develop editable supercapacitors that can be directly transferred into desirable shapes and stretchability. In this work, editable supercapacitors for customizable shapes and stretchability using electrodes based on mechanically strengthened ultralong MnO2 nanowire composites are developed. A supercapacitor edited with honeycomb-like structure shows a specific capacitance of 227.2 mF cm-2 and can be stretched up to 500% without degradation of electrochemical performance, which is superior to most of the state-of-the-art stretchable supercapacitors. In addition, it maintains nearly 98% of the initial capacitance after 10 000 stretch-and-release cycles under 400% tensile strain. As a representative of concept for system integration, the editable supercapacitors are integrated with a strain sensor, and the system exhibits a stable sensing performance even under arm swing. Being highly stretchable, easily programmable, as well as connectable in series and parallel, an editable supercapacitor with customizable stretchability is promising to produce stylish energy storage devices to power various portable, stretchable, and wearable devices.

16.
Adv Mater ; 28(8): 1567-76, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26690727

RESUMO

Solution-processable inks based on lithium titanate with a conductive network architecture, toward high-rate lithium-ion batteries (LIBs) with a customized configuration are developed. The inks, with tunable viscosity, are compatible for on-demand coating techniques. The lithium titanate electrode derived from these inks exhibits excellent high-rate capacity (≈124 mA h g(-1) at 90 C, 15.7 A g(-1) ) after 1000 cycles.

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