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1.
Chem Rev ; 124(1): 164-209, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38044580

RESUMEN

The performance of a chemical reaction is critically dependent on the electronic and/or geometric structures of a material in heterogeneous catalysis. Over the past century, the Sabatier principle has already provided a conceptual framework for optimal catalyst design by adjusting the electronic structure of the catalytic material via a change in composition. Beyond composition, it is essential to recognize that the geometric atomic structures of a catalyst, encompassing terraces, edges, steps, kinks, and corners, have a substantial impact on the activity and selectivity of a chemical reaction. Crystal-phase engineering has the capacity to bring about substantial alterations in the electronic and geometric configurations of a catalyst, enabling control over coordination numbers, morphological features, and the arrangement of surface atoms. Modulating the crystallographic phase is therefore an important strategy for improving the stability, activity, and selectivity of catalytic materials. Nonetheless, a complete understanding of how the performance depends on the crystal phase of a catalyst remains elusive, primarily due to the absence of a molecular-level view of active sites across various crystal phases. In this review, we primarily focus on assessing the dependence of catalytic performance on crystal phases to elucidate the challenges and complexities inherent in heterogeneous catalysis, ultimately aiming for improved catalyst design.

2.
Nano Lett ; 24(25): 7688-7697, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38869197

RESUMEN

Radiation-tolerance and repairable flexible transistors and integrated circuits (ICs) with low power consumption have become hot topics due to their wide applications in outer space, nuclear power plants, and X-ray imaging. Here, we designed and developed novel flexible semiconducting single-walled carbon nanotube (sc-SWCNT) thin-film transistors (TFTs) and ICs. Sc-SWCNT solid-electrolyte-gate dielectric (SEGD) TFTs showcase symmetric ambipolar characteristics with flat-band voltages (VFB) of ∼0 V, high ION/IOFF ratios (>105), and the recorded irradiation resistance (up to 22 Mrad). Moreover, flexible sc-SWCNT ICs, including CMOS-like inverters and NAND and NOR logic gates, have excellent operating characteristics with low power consumption (≤8.4 pW) and excellent irradiation resistance. Significantly, sc-SWCNT SEGD TFTs and ICs after radiation with a total irradiation dose (TID) ≥ 11 Mrad can be repaired after thermal heating at 100 °C. These outstanding characteristics are attributed to the designed device structures and key core materials including SEGD and sc-SWCNT.

3.
Nano Lett ; 24(25): 7732-7740, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38869233

RESUMEN

Rechargeable lithium-ion batteries are integral to contemporary energy storage, yet current anode material systems struggle to meet the increasing demand for extended range capabilities. This work introduces a novel composite anode material composed of one-dimensional 2H-phase tin disulfide (SnS2) nanoribbons enclosed within cavities of single-walled carbon nanotubes (SnS2@SWCNTs), achieved through precise atomic engineering. Employing aberration-corrected transmission electron microscopy, we precisely elucidated the crystal structure of SnS2 within the confines of the SWCNTs. This deliberate design effectively addresses the inherent limitations of SnS2 as a lithium-ion anode material, including its low electrical conductivity, considerable volume expansion effects, and unstable solid electrolyte interface membrane. Testing confirmed that SnS2 transforms into the Li5Sn2 alloy phase after full lithiation and back to SnS2 after delithiation, showing excellent reversibility. The composite also benefits from edge effects, improving lithium storage through stronger binding and lower migration barriers, which were supported by calculations. This pioneering work advances high-performance anode materials for applications.

4.
Small ; 19(20): e2207311, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36782084

RESUMEN

The threshold voltage (Vth ) adjustment of complementary metal-oxide-semiconductor (CMOS) thin film transistors (TFTs) is one of the research hotspots due to its key role in energy consumption control of CMOS circuits. Here, ultralow-power flexible CMOS circuits based on well-matched enhancement-mode (E-mode) CMOS single-walled carbon nanotube (SWCNT) TFTs are successfully achieved through tuning the work function of gate electrodes, electron doping, and printing techniques. E-mode P-type CMOS SWCNT TFTs with the full-solution procedure are first obtained through decreasing the work function of Ag gate electrodes directly caused by the deposition of bismuth iodide (BiI3 )-doped solid-state electrolyte dielectrics. After synthetic optimization of dielectric compositions and semiconductor printing process, the flexible printed E-mode SWCNT TFTs show the high Ion /Ioff ratios of ≈106 , small subthreshold swing (SS) of 70-85 mV dec-1 , low operating voltages of ≈0.5 to -1.5 V, good stability and excellent mechanical flexibility during 10 000 bending cycles. E-mode N-type SWCNT TFTs are then selectively achieved via printing the polarity conversion ink (2-Amino-2-methyl-1-propanol (AMP)  as electron  doping agent) in P- type TFT channels. Last, printed SWCNT CMOS inverters are successfully constructed with full rail-to-rail output characteristics and the record unit static power consumption of 6.75 fW µm-1 at VDD of 0.2 V.

5.
Exp Cell Res ; 414(1): 113082, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35218724

RESUMEN

BACKGROUND: Osteosarcoma (OS) is the most common primary bone malignancy. Circular RNAs (circRNAs) have been implicated in OS pathogenesis. In the current study, we explored the precise role of circRNA cyclin dependent kinase 14 (circ-CDK14, hsa_circ_0001721) in OS progression. METHODS: The levels of circ-CDK14, miR-198 and E2F transcription factor 2 (E2F2) were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Cell viability, apoptosis, migration and invasion were determined using the Cell Counting-8 Kit (CCK-8), flow cytometry and transwell assays, respectively. Glucose consumption, lactate production and adenosine triphosphate (ATP) level were gauged using the commercial assay kits. The direct relationship between miR-198 and circ-CDK14 or E2F2 was confirmed by dual-luciferase reporter, RNA pull-down and RNA immunoprecipitation (RIP) assays. Animal studies were used to analyze the role of circ-CDK14 in vivo. RESULTS: Our data revealed that circ-CDK14 was up-regulated and miR-198 was down-regulated in OS tissues and cell lines. Circ-CDK14 silencing suppressed OS cell viability, migration, invasion, and glycolysis and promoted cell apoptosis in vitro, as well as diminished tumor growth in vivo. Mechanistically, circ-CDK14 directly targeted miR-198. Moreover, miR-198 was a functional mediator of circ-CDK14 in regulating OS cell progression in vitro. E2F2 was a direct target of miR-198, and miR-198 overexpression regulated OS cell progression in vitro by down-regulating E2F2. Furthermore, circ-CDK14 regulated E2F2 expression by functioning as a sponge of miR-198 in OS cells. CONCLUSION: Our findings demonstrate the inhibitory effect of circ-CDK14 silencing on OS progression by targeting the miR-198/E2F2 axis, establishing a strong rationale for decreasing circ-CDK14 as a novel therapeutic strategy for OS.


Asunto(s)
Neoplasias Óseas , MicroARNs , Osteosarcoma , Animales , Neoplasias Óseas/patología , Línea Celular Tumoral , Proliferación Celular/genética , MicroARNs/genética , MicroARNs/metabolismo , Osteosarcoma/metabolismo , ARN Circular/genética
6.
Int Heart J ; 64(6): 970-978, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37967976

RESUMEN

Hypertensive patients with snoring and elevated plasma homocysteine levels are common. When these factors are combined, the risk of coronary heart disease (CHD) is high. Herein, we developed and validated an easy-to-use nomogram to predict high-risk CHD in snoring hypertensive patients with elevated plasma homocysteine.Snoring patients (n = 1,962) with hyperhomocysteinemia and hypertension were divided into training (n = 1,373, 70%) and validation (n = 589, 30%) sets. We extracted CHD predictors using multivariate Cox regression analysis, then constructed a nomogram model. Internal validation using 1,000 bootstrap resampling was performed to assess the consistency and discrimination of the predictive model using the area under the receiver operating characteristic curve (AUC) and calibration plots.We constructed a nomogram model with the extracted predictors, including age, waist-height ratio, smoking, and low-density lipoprotein cholesterol levels. The AUCs of the training and validation cohorts at 80 months were 0.735 (95% CI: 0.678-0.792) and 0.646 (95% CI: 0.547-0.746), respectively. The consistency between the observed CHD survival and the probability of CHD survival in the training and validation sets was acceptable based on the calibration plots. A total of more than 151 points in the nomogram can be used in the identification of high-risk patients for CHD among snoring hypertensive patients with elevated plasma homocysteine.We developed a CHD risk prediction model for snoring hypertension patients with hyperhomocysteinemia. Our findings provide a useful clinical tool for the rapid identification of high-risk CHD at an early stage.


Asunto(s)
Enfermedad Coronaria , Hiperhomocisteinemia , Hipertensión , Humanos , Hiperhomocisteinemia/complicaciones , Hiperhomocisteinemia/diagnóstico , Hiperhomocisteinemia/epidemiología , Ronquido/epidemiología , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/epidemiología , Hipertensión/complicaciones , Hipertensión/epidemiología , Homocisteína , Nomogramas
7.
Bioorg Med Chem ; 25(15): 4088-4099, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28622907

RESUMEN

Two series of novel 5,7-diarylimidazo[1,2-a]pyridine-8-carbonitrile derivatives (3a-3q and 7a-7n) were designed by modification of CA-4 pharmacophore to develop colchicine targeted antitubulin agents. All compounds were efficiently synthesized and evaluated for their cytotoxicity against five selected cancer cell lines (HT-29, H460, A549, MKN-45 and SMMC-7721) which got an insight in structure and activity relationships (SARs). Several molecules (7e, 7f, 7h-7j and 7m) were disclosed to exhibit promising antiproliferative activity with IC50 values in double-digit nanomolar degree. Optimization toward these compounds led to the discovery of a promising lead 7e, which showed noteworthy potency with IC50 value ranging from 0.01 to 3.2µM superior to CA-4 and Crolibulin. Importantly, immunofluorescence staining and colchcine competitive binding assay revealed that microtubule dynamics was disrupted by 7e by binding at the colchicine site of tubulin. Moreover, molecular docking studies suggested the binding of this mimic at colchcine-binding site is similar to Crolibulin, as was in conformity with the observed SARs for these compounds.


Asunto(s)
Piridinas/síntesis química , Piridinas/farmacología , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/farmacología , Técnica del Anticuerpo Fluorescente , Células HT29 , Humanos , Modelos Moleculares , Espectroscopía de Protones por Resonancia Magnética , Piridinas/química , Espectrometría de Masa por Ionización de Electrospray , Relación Estructura-Actividad , Moduladores de Tubulina/química
8.
Sensors (Basel) ; 17(12)2017 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-29168775

RESUMEN

Motion capture of the human body potentially holds great significance for exoskeleton robots, human-computer interaction, sports analysis, rehabilitation research, and many other areas. Dielectric elastomer sensors (DESs) are excellent candidates for wearable human motion capture systems because of their intrinsic characteristics of softness, light weight, and compliance. In this paper, DESs were applied to measure all component motions of the wrist joints. Five sensors were mounted to different positions on the wrist, and each one is for one component motion. To find the best position to mount the sensors, the distribution of the muscles is analyzed. Even so, the component motions and the deformation of the sensors are coupled; therefore, a decoupling method was developed. By the decoupling algorithm, all component motions can be measured with a precision of 5°, which meets the requirements of general motion capture systems.


Asunto(s)
Dispositivos Electrónicos Vestibles , Elastómeros , Diseño de Equipo , Movimiento (Física) , Articulación de la Muñeca
9.
Small ; 12(36): 5066-5073, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27152874

RESUMEN

P-type and n-type top-gate carbon nanotube thin-film transistors (TFTs) can be selectively and simultaneously fabricated on the same polyethylene terephthalate (PET) substrate by tuning the types of polymer-sorted semiconducting single-walled carbon nanotube (sc-SWCNT) inks, along with low temperature growth of HfO2 thin films as shared dielectric layers. Both the p-type and n-type TFTs show good electrical properties with on/off ratio of ≈105 , mobility of ≈15 cm2 V-1 s-1 , and small hysteresis. Complementary metal oxide semiconductor (CMOS)-like logic gates and circuits based on as-prepared p-type and n-type TFTs have been achieved. Flexible CMOS-like inverters exhibit large noise margin of 84% at low voltage (1/2 Vdd = 1.5 V) and maximum voltage gain of 30 at Vdd of 1.5 V and low power consumption of 0.1 µW. Both of the noise margin and voltage gain are one of the best values reported for flexible CMOS-like inverters at Vdd less than 2 V. The printed CMOS-like inverters work well at 10 kHz with 2% voltage loss and delay time of ≈15 µs. A 3-stage ring oscillator has also been demonstrated on PET substrates and the oscillation frequency of 3.3 kHz at Vdd of 1 V is achieved.

10.
Soft Robot ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38781417

RESUMEN

Continuum manipulators can improve spatial adaptability and operational flexibility in constrained environments by endowing them with contraction and extension capabilities. There are currently desired requirements to quantify the shape of an extensible continuum manipulator for strengthening its obstacle avoidance capability and end-effector position accuracy. To address these issues, this study proposes a methodology of using silicone rubber strain sensors (SRSS) to estimate the shape of an extensible continuum manipulator. The way is to measure the strain at specific locations on the deformable body of the manipulator, and then reconstruct the shape by integrating the information from all sensors. The slender sensors are fabricated by a rolling process that transforms planar silicone rubber sensors into cylindrical structures. The proprioceptive model relationship between the strain of the sensor and the deformation of the manipulator is established with considering the phenomenon of torsion of the manipulator caused by compression. The physically extensible continuum manipulator equipped with three driving tendons and nine SRSS was designed. Comprehensive evaluations of various motion trajectories indicate that this method can accurately reconstruct the shape of the manipulator, especially under end-effector loads. The experimental results demonstrate that the mean (maximum) absolute position error of the endpoint is 1.61% (3.45%) of the manipulator length.

11.
Talanta ; 276: 126285, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38781918

RESUMEN

The advent of flexible single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) has transformed electronics, providing significant benefits like low operating voltage, reduced power consumption, cost-effectiveness, and improved signal amplification. This study focuses on leveraging these attributes to develop a novel flexible high-sensitivity and energy-efficient chloride ion sensors based on printed flexible SWCNT-TFTs utilizing polymers-sorted semiconducting SWCNTs (sc-SWCNTs) as the active layers and ion liquids-poly(4-vinylphenol as dielectric layers along with the evaporated deposition of aluminum electrodes and printed silver electrodes as the gate and source-drain electrodes, respectively. The sensors exhibit several operational advantages, including low voltage requirements (≤1 V), rapid response speed (5.32 s), significant signal amplification (Up to 702.6 %), low power consumption (0.31 µJ at 1 mmol chloride ion), good repeatability, high sensitivity for both low and high concentrations of chloride ion (up to 100 mmol/L) and excellent mechanical flexibility (No obvious changes after bending for 10,000 times with a 5 mm radius). The detection mechanism of chloride ions was analyzed using X-ray Photoelectron Spectroscopy (XPS). It was found that chloride ions react with silver nanoparticles (AgNPs) to form silver chloride (AgCl) on printed electrodes, impeding carrier transport and reducing the currents in SWCNT TFTs. Importantly, our sensors' compatibility with smart devices allows for real-time monitoring of chloride ion levels in human sweat, offering significant potential for daily health monitoring.

12.
Small Methods ; : e2400359, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38845084

RESUMEN

To simulate biological visual systems and surpass their functions and performance, it is essential to develop high-performance optoelectronic neuromorphic electronics with broadband response, low power consumption, and fast response speed. Among these, optoelectronic synaptic transistors have emerged as promising candidates for constructing neuromorphic visual systems. In this work, flexible printed broadband (from 275 to 1050 nm) optoelectronic carbon nanotube synaptic transistors with good stability, high response speed (3.14 ms), and low-power consumption (as low as 0.1 fJ per event with the 1050 nm pulse illumination) using PbS quantum dots (QDs) modified semiconducting single-walled carbon nanotubes (sc-SWCNTs) as active layers are developed. In response to optical pulses within the ultraviolet to near-infrared wavelength range, the optoelectronic neuromorphic devices exhibit excitatory postsynaptic current, paired-pulse facilitation, and a transition from short-term plasticity to long-term plasticity, and other optical synaptic behaviors. Furthermore, a simplified neural morphology visual array is developed to simulate integrated functions such as image perception, memory, and preprocessing. More importantly, it can also emulate other complicated bionic functions, such as the infrared perception of salmon eyes and the warning behavior of reindeer in different environments. This work holds immense significance in advancing the development of artificial neural visual systems.

13.
ACS Nano ; 18(22): 14298-14311, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38787538

RESUMEN

The development of large-scale integration of optoelectronic neuromorphic devices with ultralow power consumption and broadband responses is essential for high-performance bionics vision systems. In this work, we developed a strategy to construct large-scale (40 × 30) enhancement-mode carbon nanotube optoelectronic synaptic transistors with ultralow power consumption (33.9 aJ per pulse) and broadband responses (from 365 to 620 nm) using low-work function yttrium (Y)-gate electrodes and the mixture of eco-friendly photosensitive Ag2S quantum dots (QDs) and ionic liquids (ILs)-cross-linking-poly(4-vinylphenol) (PVP) (ILs-c-PVP) as the dielectric layers. Solution-processable carbon nanotube thin-film transistors (TFTs) showed enhancement-mode characteristics with the wide and controllable threshold voltage window (-1 V∼0 V) owing to use of the low-work-function Y-gate electrodes. It is noted that carbon nanotube optoelectronic synaptic transistors exhibited high on/off ratios (>106), small hysteresis and low operating voltage (≤2 V), and enhancement mode even under the illumination of ultraviolet (UV, 365 nm), blue (450 nm), and green (550 nm) to red (620 nm) pulse lights when introducing eco-friendly Ag2S QDs in dielectric layers, demonstrating that they have the strong fault-tolerant ability for the threshold voltage drifts caused by various manufacturing scenarios. Furthermore, some important bionic functions including a high paired pulse facilitation index (PPF index, up to 290%), learning and memory function with the long duration (200 s), and rapid recovery (2 s). Pavlov's dog experiment (retention time up to 20 min) and visual memory forgetting experiments (the duration of high current for 180 s) are also demonstrated. Significantly, the optoelectronic synaptic transistors can be used to simulate the adaptive process of vision in varying light conditions, and we demonstrated the dynamic transition of light adaptation to dark adaptation based on light-induced conditional behavior. This work undoubtedly provides valuable insights for the future development of artificial vision systems.

14.
J Food Sci ; 89(9): 5980-5992, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39042465

RESUMEN

In the evolving field of food safety, rapid and precise detection of antibiotic residues is crucial. This study aimed to tackle this challenge by integrating advanced inkjet printing technology with sophisticated microfluidic paper-based analytical devices (µPADs). The µPAD design utilized "green" quantum dots synthesized via an eco-friendly hydrothermal method using green white mulberry leaves as the carbon source, serving as the key fluorescent detection material. The action mechanism involved a photoinduced electron transfer system using red carbon dots (CDs) as electron donors and blue CDs combined with two-dimensional layered molybdenum disulfide (MoS2) nanosheets as electron acceptors. This system could quickly detect antibiotics within 10 min in pork and water samples, demonstrating high sensitivity and recovery rates: 6.5 pmol/L at 99.75%-110% for sulfadimethoxine, 3.3 pmol/L at 99%-105% for sulfamethoxazole, and 8.5 pmol/L at 98.5%-105% for tetracycline. It achieved a relative standard deviation under 5%, ensuring reliability and reproducibility. The fabricated sensor offered a promising application for the rapid and efficient on-site detection of antibiotic residues in food.


Asunto(s)
Antibacterianos , Carbono , Contaminación de Alimentos , Puntos Cuánticos , Carbono/química , Antibacterianos/análisis , Puntos Cuánticos/química , Animales , Porcinos , Contaminación de Alimentos/análisis , Fluorescencia , Residuos de Medicamentos/análisis , Reproducibilidad de los Resultados , Dispositivos Laboratorio en un Chip , Espectrometría de Fluorescencia/métodos , Agua , Morus/química
15.
JACS Au ; 4(8): 2886-2895, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39211593

RESUMEN

The development of alternative alloy catalysts with high activity, surpassing platinum group metals, for the oxygen reduction reaction (ORR) is urgently needed in the field of electrocatalysis. The Ag-based single-atom alloy (AgSAA) cluster has been proposed as a promising catalyst for the ORR; however, enhancing its activity under operational conditions remains challenging due to limited insights into its actual active site. Here, we demonstrate that the operando formation of the MO x (OH) y complex serves as the key active site for catalyzing the ORR over AgSAA cluster catalysts, as revealed through comprehensive neural network potential molecular dynamics simulations combined with first-principles calculations. The volcano plot of the ORR over the MO x (OH) y complex addresses the gaps inherent in traditional metallic alloy models for pure AgSAA cluster catalysts in ORR catalysis. The appropriate orbital hybridization between OH and the dopant metal in the MO x (OH) y complexes indicated that the Ag54Co1, Ag54Pd1, and Ag54Au1 clusters are optimal AgSAA catalysts for the ORR. Our work underscores the significance of theoretical modeling considering the reaction atmosphere in uncovering the true active site for the ORR, which can be extended to other reaction systems for rational catalyst design.

16.
Plant Physiol Biochem ; 214: 108934, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39003974

RESUMEN

Apple (Malus domestica Borkh.) is among the most widely planted and economically valuable horticultural crops globally. Over time, the apple fruit's cut surface undergoes browning, and the degree of browning varies among different apple varieties. Browning not only affects the appearance of fruits but also adversely affects their taste and flavor. In the present study, we observed browning in different apple varieties over time and analyzed the expression of genes in the polyphenol oxidase gene family. The results indicated a strong correlation between the browning degree of the fruit and the relative expression of the polyphenol oxidase gene MdPPO2. With the MdPPO2 promoter as bait, the basic leucine zipper (bZIP) transcription factor MdbZIP44 was identified using the yeast single-hybrid screening method. Further investigation revealed that the overexpression of MdbZIP44 in 'Orin' callus could enhance the expression of MdPPO2 and promote browning of the callus. However, knocking out MdbZIP44 resulted in a callus with no apparent browning phenotype. In addition, our results confirmed the interaction between MdbZIP44 and MdbZIP11. In conclusion, the results indicated that MdbZIP44 can induce apple fruit browning by activating the MdPPO2 promoter. The results provide a theoretical basis for further clarifying the browning mechanism of apple fruit.


Asunto(s)
Frutas , Malus , Proteínas de Plantas , Regiones Promotoras Genéticas , Malus/genética , Malus/metabolismo , Regiones Promotoras Genéticas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Frutas/genética , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Catecol Oxidasa/metabolismo , Catecol Oxidasa/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética
17.
Adv Sci (Weinh) ; 11(29): e2401794, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38828719

RESUMEN

The development of neuromorphic optoelectronic systems opens up the possibility of the next generation of artificial vision. In this work, the novel broadband (from 365 to 940 nm) and multilevel storage optoelectronic synaptic thin-film transistor (TFT) arrays are reported using the photosensitive conjugated polymer (poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(bithiophene)], F8T2) sorted semiconducting single-walled carbon nanotubes (sc-SWCNTs) as channel materials. The broadband synaptic responses are inherited to absorption from both photosensitive F8T2 and sorted sc-SWCNTs, and the excellent optoelectronic synaptic behaviors with 200 linearly increasing conductance states and long retention time > 103 s are attributed to the superior charge trapping at the AlOx dielectric layer grown by atomic layer deposition. Furthermore, the synaptic TFTs can achieve IOn/IOff ratios up to 106 and optoelectronic synaptic plasticity with the low power consumption (59 aJ per single pulse), which can simulate not only basic biological synaptic functions but also optical write and electrical erase, multilevel storage, and image recognition. Further, a novel Spiking Neural Network algorithm based on hardware characteristics is designed for the recognition task of Caltech 101 dataset and multiple features of the images are successfully extracted with higher accuracy (97.92%) of the recognition task from the multi-frequency curves of the optoelectronic synaptic devices.

18.
Diabetes Metab Syndr Obes ; 17: 2671-2681, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38978818

RESUMEN

Background: A newly introduced obesity-related index, the weight-adjusted-waist index (WWI), emerges as a promising predictor of cardiovascular disease (CVD). Given the known synergistic effects of hypertension and obstructive sleep apnea (OSA) on cardiovascular risk, we aimed to explore the relationship between the WWI and CVD risk specifically within this high-risk cohort. Methods: A total of 2265 participants with hypertension and OSA were included in the study. Multivariate Cox regression analysis was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for CVD events. The restricted cubic spline (RCS) was used to further evaluate the nonlinear dose-response relationship. Results: During a median follow-up period of 6.8 years, 324 participants experienced a CVD event. Multivariate Cox regression analysis revealed that compared to the reference group, the HRs for the second, third, and fourth groups were 1.12 (95% CI, 0.79-1.59), 1.35 (95% CI, 0.96-1.89), and 1.58 (95% CI, 1.13-2.22), respectively. Moreover, RCS analysis illustrated a clear J-shaped relationship between the WWI and CVD risk, particularly notable when WWI exceeded 11.5 cm/√kg, signifying a significant increase in CVD risk. Conclusion: There was a J-shaped relationship between WWI and CVD in hypertensive patients with OSA, especially when the WWI was greater than 11.5 cm/√kg, the risk of CVD was significantly increased.

19.
Injury ; 54(10): 110977, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37684116

RESUMEN

OBJECTIVE: To investigate the clinical efficacy of three-dimensional (3D) printing-assisted shaping titanium cage combined with Masquelet technology in the treatment of calcaneal infectious defects. METHODS: A retrospective analysis was performed of the data from nine patients with chronic calcaneal infection defects treated with distal gastronal flap coverage and one patient with free anterolateral thigh flap coverage, also using a 3D printing-assisted shaping titanium cage combined with both mask technology and rib autografting from January 2017 to January 2019. There were seven males and three females, with a mean age of 37 years (range, 17-52 years). The injury mechanism of the 10 patients included four motor vehicle incidents, four high fall injuries, and two rolling compactions. All patients were treated by two⁃stage procedures. The first stage included debridement, polymethyl methacrylate (PMMA) filling, and regional flap coverage. The soft tissue defect of the 10 cases included 80 cm2 in four cases and 56 cm2, 40 cm2, and 15 cm2 in each of two cases. The bone defect was 24 cm3 and 18 cm3 in each of four cases and 3 cm3 in two cases. The second stage was the mask technology of 3D printing-assisted shaping titanium cage combined with rib autografting. Time of bone union, calcaneus morphology, implant position, and the Maryland and AOFAS hind foot scores were recorded to evaluate the clinical outcome. RESULTS: All 10 patients were followed up for a mean of 18.5 months (range, 12-30 months). Infection occurred in two patients 2 months after the first stage operation and were successfully treated by debridement and PMMA replacement. The incision of the other eight cases all healed successfully. Cultures from the 10 cases included five cases of methicillin-resistant Staphylococcus aureus, three cases of S. aureus, and one case each of Escherichia coli and Pseudomonas aeruginosa. All 10 patients exhibited calcaneus bone union after the second stage operation. The mean time for bone union was 4.32 (range, 3-8) months. Bone trabeculae were observed in a CT scan 13 (range, 10-22) months post-operation. The mean Maryland score at 12 months post-operation was 92 (range, 86-98) and the mean AOFAS ankle hind foot score was 89.8 (range, 83-100). CONCLUSION: Three-dimensional printing-assisted shaping titanium cages and Masquelet technology may be effective methods for the treatment of infectious calcaneal defects.


Asunto(s)
Calcáneo , Staphylococcus aureus Resistente a Meticilina , Osteomielitis , Femenino , Masculino , Humanos , Adulto , Titanio , Polimetil Metacrilato , Estudios Retrospectivos , Staphylococcus aureus , Osteomielitis/diagnóstico por imagen , Osteomielitis/cirugía , Impresión Tridimensional , Calcáneo/diagnóstico por imagen , Calcáneo/cirugía
20.
Soft Robot ; 10(2): 280-291, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35944266

RESUMEN

In this article, a cable-driven elastic backbone worm-like robot (named "SpringWorm") of decimeter-level size is designed, which has high adaptability in crack inspection of the weld between reactor pressure vessel (RPV) and control rod drive mechanisms. The robot consists of a body that adopts a rectangular helix spring backbone driven by four cables and the flexible claws embedded with distributed electromagnets. Combining the omnidirectional deformation of the backbone and the passive deformation adsorption of the claws, the robot can achieve a variety of gaits. Based on the approaches of geometric analysis and transformation matrices of the coordinate frame, a kinematic model of the cable-driven backbone has been established. Moreover, a mechanical model considering the friction between the cable and the backbone has also been established. The top position and the bending angle of the backbone obtained by the theory, simulation, and experiment are in good agreement. In addition, the errors of the driving force between simulation and experimental results are also small. SpringWorm is 670 g, measures 206 × 65 × 75 mm, has a maximum speed of 8.9 mm/s, and has a maximum payload of 1 kg. The robot can climb over 2-cm-tall steps and 4-cm-deep ditches, and climb and turn on the vertical wall, on the pipe with a radius of 31 cm, and on the spherical surface of RPV.

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