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1.
Nature ; 627(8003): 313-320, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38480964

RESUMO

Intrinsically stretchable electronics with skin-like mechanical properties have been identified as a promising platform for emerging applications ranging from continuous physiological monitoring to real-time analysis of health conditions, to closed-loop delivery of autonomous medical treatment1-7. However, current technologies could only reach electrical performance at amorphous-silicon level (that is, charge-carrier mobility of about 1 cm2 V-1 s-1), low integration scale (for example, 54 transistors per circuit) and limited functionalities8-11. Here we report high-density, intrinsically stretchable transistors and integrated circuits with high driving ability, high operation speed and large-scale integration. They were enabled by a combination of innovations in materials, fabrication process design, device engineering and circuit design. Our intrinsically stretchable transistors exhibit an average field-effect mobility of more than 20 cm2 V-1 s-1 under 100% strain, a device density of 100,000 transistors per cm2, including interconnects and a high drive current of around 2 µA µm-1 at a supply voltage of 5 V. Notably, these achieved parameters are on par with state-of-the-art flexible transistors based on metal-oxide, carbon nanotube and polycrystalline silicon materials on plastic substrates12-14. Furthermore, we realize a large-scale integrated circuit with more than 1,000 transistors and a stage-switching frequency greater than 1 MHz, for the first time, to our knowledge, in intrinsically stretchable electronics. Moreover, we demonstrate a high-throughput braille recognition system that surpasses human skin sensing ability, enabled by an active-matrix tactile sensor array with a record-high density of 2,500 units per cm2, and a light-emitting diode display with a high refreshing speed of 60 Hz and excellent mechanical robustness. The above advancements in device performance have substantially enhanced the abilities of skin-like electronics.


Assuntos
Desenho de Equipamento , Pele , Transistores Eletrônicos , Dispositivos Eletrônicos Vestíveis , Humanos , Silício , Nanotubos de Carbono , Tato
3.
Front Cardiovasc Med ; 10: 1291089, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38089776

RESUMO

Aortic stenosis (AS) complicated with acute ST-segment elevation myocardial infarction (STEMI) is a life-threatening emergency with high mortality. A 75-year-old male patient attended the emergency department of Wuhan Asia Heart Hospital in December 2021 with chest pain for 2 days and exacerbation for 1 h. The electrocardiogram (ECG) indicated atrial fibrillation with rapid ventricular response and ST-segment depression. Echocardiography showed severe AS and mild/moderate aortic insufficiency. The patient refused coronary angiography and further invasive procedures and then requested discharge, but he had recurrent chest pain on the third day. The ECG showed an extensive anterior wall STEMI. During preoperative preparation, he suffered from cardiogenic shock (CS). Concomitant percutaneous coronary intervention (PCI) and transcatheter aortic valve replacement (TAVR) was performed, but he died of CS and multiple organ failure 4 days after surgery. Patients with AS and STEMI might be susceptible to CS during perioperative period of concomitant PCI and TAVR, which requires proactive prevention.

4.
Nat Commun ; 14(1): 8528, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38135683

RESUMO

Multifunctional platforms that can dynamically modulate their color and appearance have attracted attention for applications as varied as displays, signaling, camouflage, anti-counterfeiting, sensing, biomedical imaging, energy conservation, and robotics. Within this context, the development of camouflage systems with tunable spectroscopic and fluorescent properties that span the ultraviolet, visible, and near-infrared spectral regions has remained exceedingly challenging because of frequently competing materials and device design requirements. Herein, we draw inspiration from the unique blue rings of the Hapalochlaena lunulata octopus for the development of deception and signaling systems that resolve these critical challenges. As the active material, our actuator-type systems incorporate a readily-prepared and easily-processable nonacene-like molecule with an ambient-atmosphere stability that exceeds the state-of-the-art for comparable acenes by orders of magnitude. Devices from this active material feature a powerful and unique combination of advantages, including straightforward benchtop fabrication, competitive baseline performance metrics, robustness during cycling with the capacity for autonomous self-repair, and multiple dynamic multispectral operating modes. When considered together, the described exciting discoveries point to new scientific and technological opportunities in the areas of functional organic materials, reconfigurable soft actuators, and adaptive photonic systems.

5.
bioRxiv ; 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37873341

RESUMO

Bioelectronic fibers hold promise for both research and clinical applications due to their compactness, ease of implantation, and ability to incorporate various functionalities such as sensing and stimulation. However, existing devices suffer from bulkiness, rigidity, limited functionality, and low density of active components. These limitations stem from the difficulty to incorporate many components on one-dimensional (1D) fiber devices due to the incompatibility of conventional microfabrication methods (e.g., photolithography) with curved, thin and long fiber structures. Herein, we introduce a fabrication approach, ‶spiral transformation″, to convert two-dimensional (2D) films containing microfabricated devices into 1D soft fibers. This approach allows for the creation of high density multimodal soft bioelectronic fibers, termed Spiral NeuroString (S-NeuroString), while enabling precise control over the longitudinal, angular, and radial positioning and distribution of the functional components. We show the utility of S-NeuroString for motility mapping, serotonin sensing, and tissue stimulation within the dynamic and soft gastrointestinal (GI) system, as well as for single-unit recordings in the brain. The described bioelectronic fibers hold great promises for next-generation multifunctional implantable electronics.

6.
ACS Nano ; 17(18): 18392-18401, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37668312

RESUMO

Carbon superstructures are widely applied in energy and environment-related areas. Among them, the flower-like polyacrylonitrile (PAN)-derived carbon materials have shown great promise due to their high surface area, large pore volume, and improved mass transport. In this work, we report a versatile and straightforward method for synthesizing one-dimensional (1D) nanostructured fibers and two-dimensional (2D) nanostructured thin films based on flower-like PAN chemistry by taking advantage of the nucleation and growth behavior of PAN. The resulting nanofibers and thin films exhibited distinct morphologies with intersecting PAN nanosheets, which formed through rapid nucleation on existing PAN. We further constructed a variety of hierarchical PAN superstructures based on different templates, solvents, and concentrations. These PAN nanosheet superstructures can be readily converted to carbon superstructures. As a demonstration, the nanostructured thin film exhibited a contact angle of ∼180° after surface modification with fluoroalkyl monolayers, which is attributed to high surface roughness enabled by the nanosheet assemblies. This study offers a strategy for the synthesis of nanostructured carbon materials for various applications.

7.
Front Cardiovasc Med ; 10: 1167698, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283585

RESUMO

Anomalous aortic origin of a coronary artery (AAOCA) is a congenital malformation of the coronary arteries that includes several subtypes. It is a leading cause of sudden cardiac death in young people, especially in competitive athletes. An accurate diagnosis and identification of high-risk patients with AAOCA for referral for surgical repair can help in the management of these patients. However, current diagnostic tools such as invasive angiography, echocardiography, and intravascular ultrasound have known limitations in visualizing coronary orifices and characterizing vessels. In this case report, we report on a 14-year-old adolescent who suffered from repeated incidents of syncope during exercise. Using the computed tomographic fractional flow reserve (CT-FFR) technique, we diagnosed AAOCA, which revealed that his left coronary artery (LCA) originated from the right sinus of Valsalva and ran between the aorta and the pulmonary artery with an intra-arterial wall course (∼20 mm in length), with an abnormal FFR of the LCA at rest. The patient was referred for undergoing unroofing surgery, and the results of repeat CT-FFR showed a significantly improved FFR of the LCA. The patient resumed his normal physical activities without the recurrence of syncope. In this report, we highlight the usefulness of CT-FFR as a non-invasive, feasible, and effective tool to guide whether a patient with AAOCA requires surgical revascularization and to evaluate the effectiveness of the procedure after surgery.

8.
Science ; 380(6646): 735-742, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37200416

RESUMO

Artificial skin that simultaneously mimics sensory feedback and mechanical properties of natural skin holds substantial promise for next-generation robotic and medical devices. However, achieving such a biomimetic system that can seamlessly integrate with the human body remains a challenge. Through rational design and engineering of material properties, device structures, and system architectures, we realized a monolithic soft prosthetic electronic skin (e-skin). It is capable of multimodal perception, neuromorphic pulse-train signal generation, and closed-loop actuation. With a trilayer, high-permittivity elastomeric dielectric, we achieved a low subthreshold swing comparable to that of polycrystalline silicon transistors, a low operation voltage, low power consumption, and medium-scale circuit integration complexity for stretchable organic devices. Our e-skin mimics the biological sensorimotor loop, whereby a solid-state synaptic transistor elicits stronger actuation when a stimulus of increasing pressure is applied.


Assuntos
Retroalimentação Sensorial , Robótica , Pele Artificial , Dispositivos Eletrônicos Vestíveis , Humanos , Eletrônica , Pele , Transistores Eletrônicos
9.
Front Cardiovasc Med ; 10: 1134658, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37077742

RESUMO

Coronary artery spasm (CAS) is characterized by reversible diffuse or focal vasoconstriction, a phenomenon that plays an important role in the pathogenesis of ischemic heart disease. Fatal arrhythmias, such as ventricular tachycardia/fibrillation and complete atrioventricular block (AV-B), are very common in patients with CAS. Nondihydropyridine calcium channel blockers (CCBs) such as diltiazem were recommended as first-line medications for treating and preventing CAS episodes. However, its use remains controversial in CAS patients with AV-B as this type of CCB can also cause AV-B itself. Here, we present the use of diltiazem in a patient with complete AV-B caused by CAS. The patient's chest pain was rapidly relieved, and complete AV-B was promptly restored to sinus rhythm following the administration of intravenous diltiazem without any adverse effects. In this report, we highlight the useful and effective application of diltiazem for treating and preventing complete AV-B caused by CAS.

10.
Front Cardiovasc Med ; 9: 1012916, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465460

RESUMO

Electrical storm (ES) remains a major dilemma for clinicians, often presenting as a medical emergency associated with significant adverse outcomes. The mechanisms behind triggering ES are complex. Although the increased activation of the sympathetic nervous system was widely accepted as a major mechanism in initiating and maintaining ES, it's thought that the interaction between mechanical and electrical substrates may play an important role in some situations. Here we present a case of ES that was refractory to multiple antiarrhythmic medications but was stopped by interatrial shunting. We aim to highlight the importance of mechano-electric feedback (MEF) as the pathophysiological mechanisms of some types of ES and the utility of interatrial shunting as an alternative therapeutic strategy for patients with ES initially refractory to antiarrhythmic medications when there is evidence to indicate increased left ventricular filling pressure or left atrial pressure.

11.
Nature ; 603(7902): 624-630, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35322250

RESUMO

Next-generation light-emitting displays on skin should be soft, stretchable and bright1-7. Previously reported stretchable light-emitting devices were mostly based on inorganic nanomaterials, such as light-emitting capacitors, quantum dots or perovskites6-11. They either require high operating voltage or have limited stretchability and brightness, resolution or robustness under strain. On the other hand, intrinsically stretchable polymer materials hold the promise of good strain tolerance12,13. However, realizing high brightness remains a grand challenge for intrinsically stretchable light-emitting diodes. Here we report a material design strategy and fabrication processes to achieve stretchable all-polymer-based light-emitting diodes with high brightness (about 7,450 candela per square metre), current efficiency (about 5.3 candela per ampere) and stretchability (about 100 per cent strain). We fabricate stretchable all-polymer light-emitting diodes coloured red, green and blue, achieving both on-skin wireless powering and real-time displaying of pulse signals. This work signifies a considerable advancement towards high-performance stretchable displays.

12.
Water Sci Technol ; 84(10-11): 3072-3090, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34850713

RESUMO

This paper combines environmental science, inorganic chemistry, water quality monitoring and other disciplines to analyze and assess the heavy metals in the water bodies and sediments of the Fenghe River Basin (FRB) in Shaanxi Province, and reveal their sources. The Water Quality Index (WQI), Nemero Index (Pn), Geological Accumulation Index (I-geo) and Potential Ecological Risk Index (RI) are used to assess heavy metals in water and sediments. Pearson correlation analysis (CA), hierarchical cluster analysis (HCA), principal component analysis (PCA) and positive matrix factorization (PMF) models are used to study the relationship and source of heavy metals. The results show that most of the residual heavy metals in the water are below the corresponding environmental quality standards for surface water. Most of the heavy metals in the sediment exceed the background value of the soil. The factors or sources of heavy metals in water and sediment are revealed in detail through PMF models. The main sources of pollution in the region are urban construction and transportation, the electronics industry, machinery manufacturing and tourism. In water, the average contribution rates of these four sources to heavy metals were 36.8%, 11.7%, 9.4% and 42.0%, and in sediments were 8.0%, 29.2%, 23.9% and 38.9%. Therefore, these sectors should be given sufficient attention.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Medição de Risco , Rios , Poluentes Químicos da Água/análise , Qualidade da Água
13.
ACS Nano ; 15(11): 17299-17309, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34633175

RESUMO

Wrinkled surfaces and materials are found throughout the natural world in various plants and animals and are known to improve the performance of emerging optical and electrical technologies. Despite much progress, the reversible post-fabrication tuning of wrinkle sizes and geometries across multiple length scales has remained relatively challenging for some materials, and the development of comprehensive structure-function relationships for optically active wrinkled surfaces has often proven difficult. Herein, by drawing inspiration from natural cephalopod skin and leveraging methodologies established for artificial adaptive infrared platforms, we engineer systems with hierarchically reconfigurable wrinkled surface morphologies and dynamically tunable visible-to-infrared spectroscopic properties. Specifically, we demonstrate architectures for which mechanical actuation changes the surface morphological characteristics; modulates the reflectance, transmittance, and absorptance across a broad spectral window; controls the specular-to-diffuse reflectance ratios; and alters the visible and thermal appearances. Moreover, we demonstrate the incorporation of these architectures into analogous electrically actuated appearance-changing devices that feature competitive figures of merit, such as reasonable maximum areal strains, rapid response times, and good stabilities upon repeated actuation. Overall, our findings constitute another step forward in the continued development of cephalopod-inspired light- and heat-manipulating systems and may facilitate advanced applications in the areas of sensing, electronics, optics, soft robotics, and thermal management.


Assuntos
Cefalópodes , Robótica , Animais , Eletrônica , Óptica e Fotônica , Visão Ocular
14.
ACS Appl Mater Interfaces ; 13(18): 20938-20946, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33938723

RESUMO

Protein- and peptide-based proton conductors have been extensively studied because of their important roles in biological processes and established potential for bioelectronic device applications. However, despite much progress, the demonstration of long-range proton transport for such materials has remained relatively rare. Herein, we fabricate, electrically interrogate, and physically characterize films from a reflectin-derived polypeptide. The electrical measurements indicate that device-integrated films exhibit proton conductivities with values of ∼0.4 mS/cm and sustain proton transport over distances of ∼1 mm. The accompanying physical characterization indicates that the polypeptide possesses characteristics analogous to those of the parent protein class and furnishes insight into the relationship between the polypeptide's electrical functionality and structure in the solid state. When considered together, our findings hold significance for the continued development and engineering of not only reflectin-based materials but also other bioinspired proton conductors.


Assuntos
Peptídeos/química , Prótons , Fenômenos Bioquímicos , Condutividade Elétrica , Transporte de Íons , Espectroscopia de Ressonância Magnética/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Sensors (Basel) ; 20(21)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142905

RESUMO

Considering the difficult problem of robot recognition and grasping in the scenario of disorderly stacked wooden planks, a recognition and positioning method based on local image features and point pair geometric features is proposed here and we define a local patch point pair feature. First, we used self-developed scanning equipment to collect images of wood boards and a robot to drive a RGB-D camera to collect images of disorderly stacked wooden planks. The image patches cut from these images were input to a convolutional autoencoder to train and obtain a local texture feature descriptor that is robust to changes in perspective. Then, the small image patches around the point pairs of the plank model are extracted, and input into the trained encoder to obtain the feature vector of the image patch, combining the point pair geometric feature information to form a feature description code expressing the characteristics of the plank. After that, the robot drives the RGB-D camera to collect the local image patches of the point pairs in the area to be grasped in the scene of the stacked wooden planks, also obtaining the feature description code of the wooden planks to be grasped. Finally, through the process of point pair feature matching, pose voting and clustering, the pose of the plank to be grasped is determined. The robot grasping experiment here shows that both the recognition rate and grasping success rate of planks are high, reaching 95.3% and 93.8%, respectively. Compared with the traditional point pair feature method (PPF) and other methods, the method present here has obvious advantages and can be applied to stacked wood plank grasping environments.

16.
J Exp Child Psychol ; 199: 104929, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32711217

RESUMO

Existing cross-cultural findings related to school-aged children's executive function (EF) from studies using computerized tasks highlight both an East-West contrast (East > West) and potential methodological confounds (e.g., contrasting levels of computer fluency). Capitalizing on two recent data sets, this multisite study of 1,311 children living in mainland China (n = 453; Mage = 11.89 years, SD = 0.87), Hong Kong (n = 371; Mage = 12.21 years, SD = 0.99), and the United Kingdom (n = 487; Mage = 11.91 years, SD = 0.93) tested measurement invariance of a computerized EF-task battery prior to investigating cultural contrasts in mean levels of EF efficiency scores. Our models established partial scalar invariance across sites. Latent factor means were substantially lower for British children than for their counterparts from either mainland China or Hong Kong, with a significant but smaller contrast between the latter two groups. Within the Chinese sample, self-reported computer use was unrelated to variation in children's performance on online tests of EF, indicating that peripheral effects of task modality are unlikely to explain the between-culture differences in EF task performance.


Assuntos
Atitude Frente aos Computadores , Computadores , Comparação Transcultural , Função Executiva/fisiologia , Análise e Desempenho de Tarefas , Adolescente , Fatores Etários , Criança , Desenvolvimento Infantil , China , Feminino , Hong Kong , Humanos , Masculino , Autorrelato , Reino Unido
17.
Adv Mater ; 32(16): e1905717, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32128911

RESUMO

Soft, mechanically deformable materials and systems that can, on demand, manipulate light propagation within both the visible and infrared (IR) regions of the electromagnetic spectrum are desirable for applications that include sensing, optoelectronics, robotics, energy conservation, and thermal management. However, the development of such technologies remains exceptionally difficult, with relatively few examples reported to date. Herein, this challenge is addressed by engineering cephalopod-inspired adaptive camouflage platforms with multispectral functionality. First, stretchable copolymer membranes that feature outstanding unstrained protonic conductivities of up to ≈90 mS cm-1 , demonstrate increases of ≈80% in their conductivities at strains of 200%, and exhibit no loss in electrical performance even under extreme elongations of 500% are described. Next, the membranes are used for the fabrication of mechanically and electrically actuated camouflage devices that function over an unprecedented spectral window; can simultaneously modulate their visible and IR specular-to-diffuse transmittance ratios by >3000-fold and >4-fold, respectively; feature rapid response times of ≈0.6 s; and exhibit good performance after repeated actuation. These findings may afford new scientific and technological opportunities not only for adaptive optics and photonics but also for any platform that can benefit from simultaneously controlling visible light and heat.

18.
Pak J Med Sci ; 35(1): 106-112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30881406

RESUMO

BACKGROUND AND OBJECTIVE: Spontaneous coronary artery dissection (SCD) remains a rare and important cause of coronary artery disease (CAD). The purpose of this study was to describe the clinical and angiographic features in SCD and to evaluate the treatment and long-term prognosis of this condition in China. METHODS: This retrospective cohort study included 118 Chinese patients with SCD confirmed by coronary angiography. Clinical and angiographic features, treatment modalities and outcomes of SCD were estimated. RESULTS: The overall prevalence of SCD was 0.15%. Age was 57 ± 10 years; 86% patients were men; 75% presented with acute coronary syndrome (ACS); 72% had concomitant atherosclerotic CAD. SCD often affected right coronary artery (RCA) and caused a short dissection (< 20mm). A conservative therapy was used in 28% of patients and revascularization in 72% (percutaneous coronary intervention [PCI] 57%; coronary artery bypass grafting [CABG] 15%). Only one patient died during hospitalization due to multiple organ failure after CABG. During a median follow-up of 43 months (range, 1 - 158 months), 32 patients had a new-onset ACS, 9 received revascularization (7 PCI and 2 CABG), and 8 died. The Kaplan-Meier estimated 12-year rates of freedom from cardiac death and ACS were both higher in revascularization versus conservative therapy (78% versus 57%; P = 0.023; 48% versus 25%, P = 0.014). No significant difference was found in freedom from revascularization between the two therapies. CONCLUSIONS: In China, SCD was usually associated with atherosclerosis and predominantly affected male population. SCD often affected RCA and caused a short dissection. In-hospital mortality rate was low regardless of therapeutic strategy. However, a significantly better long-term prognosis was observed in the revascularization compared with conservative therapy.

19.
Science ; 359(6383): 1495-1500, 2018 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-29599237

RESUMO

Materials and systems that statically reflect radiation in the infrared region of the electromagnetic spectrum underpin the performance of many entrenched technologies, including building insulation, energy-conserving windows, spacecraft components, electronics shielding, container packaging, protective clothing, and camouflage platforms. The development of their adaptive variants, in which the infrared-reflecting properties dynamically change in response to external stimuli, has emerged as an important unmet scientific challenge. By drawing inspiration from cephalopod skin, we developed adaptive infrared-reflecting platforms that feature a simple actuation mechanism, low working temperature, tunable spectral range, weak angular dependence, fast response, stability to repeated cycling, amenability to patterning and multiplexing, autonomous operation, robust mechanical properties, and straightforward manufacturability. Our findings may open opportunities for infrared camouflage and other technologies that regulate infrared radiation.

20.
Phys Chem Chem Phys ; 20(3): 1591-1607, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29260817

RESUMO

A series of emission-tunable Ce3+/Tb3+/Eu2+ doped Ca2(Mg0.75Al0.25)(Si1.75Al0.25)O7 (denoted as CMAS) phosphors have been synthesized via a high temperature solid-state reaction method. The luminescence properties, color tuning, quantum yields (QYs), energy transfer of Ce3+ to Tb3+/Eu2+, thermal stability, performance of LED devices and ratiometric temperature sensing application have been systematically investigated, respectively. Importantly, through the study of thermal stability, we found that Ce3+ and Tb3+ co-doped samples were suitable for WLED applications, while Ce3+ and Eu2+ co-doped samples were suitable for temperature sensing applications. Due to the energy transfer, Ce3+/Tb3+ co-doped samples had high luminous efficiency and the quantum efficiency of more than 80% could be achieved. Their emission colors can modulate from blue to green. In addition, on the basis of the evaluation of the as-fabricated white LED lamps via selecting the corresponding phosphors, the CCT can reach 4275 K and the CRI can increase to 86.8, indicating that this series of phosphors can act as potential color-tunable phosphors for possible applications in ultraviolet light based white LEDs. Importantly, it is found that the fluorescence intensity ratio of CMAS : 5%Ce3+,0.5%Eu2+ displays linear correlation with temperature in a wide range of 253-373 K with a high sensitivity of 2.49% K-1, indicating that it could be a good candidate for ratiometric optical thermometry.

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