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In this study, we investigate the magnetic induction heating induced in a conducting polymer (CP) under alternative magnetic fields (AMFs). Experimental results and numerical simulations have proved that the magneto-thermal conversion of the CP is caused by the induced eddy current, which is related to the shape and intensity of the applied external AMF, and the intrinsic electrical conductivity, macrostructure and microstructure of the CP. By employing various fabrication methods, specific temperature distribution and control of thermal field within conducting polymer films and aerogels could be achieved. To exploit the potential of magnetic induction heating in CP for biomedical applications, we designed a conducting polymer aerogel-based self-adaptive heat patch and demonstrated its AMF-enabled localized heating of skin. In addition to the thermal ablation of tumor cells via magneto-thermal conversion of the CP, the promotion of neuronal differentiation at mild temperature by noninvasive magneto-electrical stimulation has also been demonstrated to be an effective strategy for tissue engineering.
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Conductividad Eléctrica , Campos Magnéticos , Polímeros , Polímeros/química , Animales , Humanos , Calor , Ingeniería de Tejidos , Ratones , CalefacciónRESUMEN
BACKGROUND: This study aimed to investigate the effects of intracoronary prourokinase thrombolysis combined with emergency percutaneous coronary intervention (PCI) on myocardial perfusion and vascular endothelial function in patients with acute ST-segment elevation myocardial infarction (STEMI). METHODS: A total of 104 patients with STEMI were collected from August 2020 to August 2022, and were divided into control group and observation group in a random manner. The control group received PCI directly, and the observation group received intracoronary prourokinase thrombolytic therapy before PCI. The treatment effects were evaluated by measuring the cardiac function indexes, including left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), and left ventricular ejection fraction (LVEF), the TIMI myocardial perfusion grade, the vascular endothelial indexes, including soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1), the von Willebrand factor (vWF), the myocardial injury indexes, including cardiac troponin I (cTnI), creatine kinase isoenzyme MB (CK-MB), and lactate dehydrogenase (LDH), and the inflammatory factors, including myeloperoxidase (MPO), C-reactive protein (CRP), and interleukin-6 (IL-6). Furthermore, the treatment safety was assessed by recording the incidence of major MACE events, 6 months after the operation. RESULTS: After treatment, LVEDD and LVESD were lower in the observation group than in the control group, and LVEF was higher (p < 0.05). The TIMI myocardial perfusion grade in the observation group was higher than in the control group, after treatment (p < 0.05). The levels of sICAM-1, sVCAM-1, and vWF were higher in the observation group than in the control group (p < 0.05). The levels of cTnI, CK-MB, and LDH in the observation group were lower than those in the control group, 24 hours after surgery. At 3 days after surgery, MPO was lower in the observation group than in the control group, and CRP and IL-6 were higher (p < 0.05). The incidence of major MACE events in the observation group was lower than that in the control group, 6 months after surgery (p < 0.05). There was 1 case of puncture site bleeding in the observation group, 1 case of puncture site bleeding and 1 case of subcutaneous ecchymosis in the control group, but no serious bleeding events, such as internal bleeding or cerebral hemorrhage, in the two groups. CONCLUSIONS: Intracoronary prourokinase thrombolytic therapy combined with emergency PCI can promote the recovery of cardiac function, improve myocardial perfusion and vascular endothelial function, and reduce inflammation and the incidence of major postoperative MACE events in acute STEMI patients.
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Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Terapia Trombolítica , Humanos , Infarto del Miocardio con Elevación del ST/fisiopatología , Infarto del Miocardio con Elevación del ST/terapia , Infarto del Miocardio con Elevación del ST/cirugía , Masculino , Persona de Mediana Edad , Femenino , Terapia Trombolítica/métodos , Terapia Trombolítica/efectos adversos , Anciano , Endotelio Vascular/fisiopatología , Endotelio Vascular/efectos de los fármacos , Resultado del Tratamiento , Activador de Plasminógeno de Tipo Uroquinasa/administración & dosificación , Fibrinolíticos/administración & dosificación , Fibrinolíticos/uso terapéutico , Fibrinolíticos/efectos adversos , Proteínas RecombinantesRESUMEN
In this paper, multiresponsive actuators based on asymmetric design of graphene-conjugated poly(3,4-ethylene dioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) gradient films have been developed by a simple drop casting method. The biomimetic actuation is attributed to the hygroscopic expansion property of PEDOT:PSS and the gradient distribution of graphene sheets within the film, which resembles the hierarchical swelling tissues of some plants in nature. Graphene-conjugated PEDOT:PSS (GCP) actuators exhibit reversible bending behavior under multistimuli such as moisture, organic vapor, electrothermal, and photothermal heating. Noticeably, the bending curvature reaches 2.15 cm-1 under applied voltage as low as 1.5 V owing to the high electrical conductivity of GCP actuator. To mimic the motions of nyctinastic plants, a GCP artificial flower that spreads its petals under sunlight illumination has been fabricated. GCP actuators have been also demonstrated as intelligent light-controlled switches for light-emitting diodes and smart curtains for thermal management. Not only do the GCP gradient films exhibit potential applications in flexible electronics and energy harvesting/storage devices but also the facile fabrication of multiresponsive GCP actuators may shed light on the development of soft robotics, artificial muscles, wearable electronics, and smart sensors.
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In this work, we observed size-dependent behavior of filler on both the thermal and electrical conductivities of nacre-like graphene-conjugated conducting polymer films and demonstrated the display of apparent Wiedemann-Franz law and tunability of Lorenz constant in such films. The maximum thermal and electrical conductivities of as-fabricated films can reach over 73 W·m-1·K-1 and 1200 S·cm-1, respectively. Furthermore, the maximum value of electromagnetic interference shielding reaches 54 dB with SSE/t over 16000 dB·cm2·g-1. These films can not only show high-quality electromagnetic interference shielding performance with small thickness and low filler ratio but also achieve simultaneous thermal management during electromagnetic shielding. The findings in this work offer new insight into designing flexible graphene-conjugated polymers with customizable thermal and electrical properties in the broad fields of thermal management systems, electromagnetic defense systems, and flexible electronic systems.
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Dorper sheep (Ovis aries) (DPS), developed in the 1930s by crossing Dorset Horn and Blackhead Persian sheep in South Africa, is a world-famous composite breed for mutton production. The genetic basis underlying this breed is yet to be elucidated. Here, we report the sequencing and assembly of a highly contiguous Dorper sheep genome via integration of Oxford Nanopore Technology (ONT) sequencing and Hi-C (chromatin conformation capture) approaches. The assembled genome was around 2.64 Gb with a contig N50 of 73.33 Mb and 140 contigs in total. More than 99.5% of the assembled sequences could be anchored to 27 chromosomes and they were annotated with 20,450 protein-coding genes. Allele-specific expression (ASE) genes of Dorper sheep were revealed through ASE analysis and they were involved in the immune system, lipid metabolism, and environmental adaptation. A total of 5,701 and 456 allelic sites were observed in the SNP and indels loci identified from relevant whole-genome resequencing data. These allelic SNP and INDEL sites were annotated in 1,002 and 294 genes, respectively. Moreover, we calculated the number of variant sites and related genes derived from the maternal and paternal ancestors, revealing the genetic basis of outstanding phenotypic performance of Dorper sheep. In conclusion, this study reports the first reference genome of Dorper sheep and reveals its genetic basis through ASE. This study also provides a pipeline for mining genetic information of composite breeds, which has an implication for future hybrid-breeding practices.
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This paper studies the impact of hot pressing on the electrical and thermal performance of thick (thickness >5 µm) conducting polymer poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films after acid treatment. Thick conducting polymer films usually exhibit low electrical and thermal conductivities similar to bulk polymer because charge and heat carriers are easily scattered by the irregular arrangement of crystalline domains inside the polymer. In this work, the in-plane electrical conductivity of thick hot-pressed PEDOT:PSS film exceeded 1500 S/cm, and 50% enhancement was obtained in comparison with its non-hot-pressed counterparts. Its in-plane thermal conductivity reached as high as 1.11 W/mK (improved by almost 100% compared to acid-treated PEDOT:PSS films), which is comparable to that of some commercial thermal pads. Such electrical and thermal enhancement via the hot-pressing process is attributed to the optimized morphology and microstructures, which provide short paths for thermal and electrical transportation. We have also demonstrated that the hot-pressed PEDOT:PSS films could be potentially utilized as a flexible conductor and heat spreader for application in flexible electronics and thermal management, respectively. This study not only offers a new insight into the process-property relationship for conducting polymers but also further enables the use of PEDOT:PSS films with simultaneously improved electrical and thermal performance in practical applications, such as thermal management for organic electrodes in batteries, flexible electronics, soft robotics, and bioelectronics.
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Hair follicle development and wool shedding in sheep are poorly understood. This study investigated the population structures and genetic differences between sheep with different wool types to identify candidate genes related to these traits. We used Illumina ovine SNP 50K chip genotyping data of 795 sheep populations comprising 27 breeds with two wool types, measuring the population differentiation index (Fst), nucleotide diversity (θπ ratio), and extended haplotype homozygosity among populations (XP-EHH) to detect the selective signatures of hair sheep and fine-wool sheep. The top 5% of the Fst and θπ ratio values, and values of XP-EHH < -2 were considered strongly selected SNP sites. Annotation showed that the PRX, SOX18, TGM3, and TCF3 genes related to hair follicle development and wool shedding were strongly selected. Our results indicated that these methods identified important genes related to hair follicle formation, epidermal differentiation, and hair follicle stem cell development, and provide a meaningful reference for further study on the molecular mechanisms of economically important traits in sheep.
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Folículo Piloso/crecimiento & desarrollo , Ovinos/genética , Lana , Animales , Análisis Mutacional de ADN/veterinaria , Estudio de Asociación del Genoma Completo/veterinaria , Técnicas de Genotipaje/veterinaria , Anotación de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Análisis de Componente Principal , Ovinos/crecimiento & desarrollo , Oveja Doméstica , Especificidad de la Especie , Lana/crecimiento & desarrolloRESUMEN
Nano-fibrillated celluloses (NFCs) were separated from bleached softwood kraft pulp. Through the periodate oxidation method, 2,3-dialdehyde nano-fibrillated celluloses (DNFCs) with varied aldehyde content were prepared. The high aldehyde content, large specific surface area and high surface charge density of DNFCs benefited the adsorbing of Cu (II). The adsorption kinetics and isotherms presented good correlations with the Pseudo-second-order model and Freundlich model, respectively. Both physical and chemical adsorptions existed in the Cu (II) adsorption by DNFCs, while chemisorption was the rate-limiting step. The adsorption thermodynamic parameters Gibbs free energy change (ΔG), enthalpy change (ΔH) and entropy change (ΔS) were also investigated. This study provides theoretical support for applying DNFCs to remove metal ions from aqueous solutions.
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Camellia Oleifera Shell (COS) is a kind of renewable lignocellulose resource and contains abundant hemicelluloses. In this work, the hemicelluloses in COS were extracted by alkali treatment and precipitated by ethanol with different concentration. Thermal pyrolysis kinetics of COS hemicelluloses were investigated using a thermogravimetric analyzer at the heating rates of 5, 10, and 20⯰C/min based on Coats-Redfern, Flynn-Wall-Ozawa (FWO), and Kissinger-Akahira-Sunose (KAS) model. The results showed that the best fitting thermal pyrolysis mechanism of COS hemicelluloses was one-dimensional diffusion reaction analyzed by Coats-Redfern model. The activation energies of COS hemicelluloses ranged from 175.07 to 247.87â¯kJ·mol-1 and from 174.74 to 252.50â¯kJ·mol-1 calculated by FWO and KAS, respectively. The thermal stabilities of COS hemicelluloses were enhanced with the precipitated ethanol concentration increasing, and reflected by thermodynamic parameters ΔH, ΔG and ΔS. This study may provide basic theoretical supports for the thermochemical conversion of COS hemicelluloses.
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Camellia/química , Polisacáridos/química , Cinética , Polisacáridos/aislamiento & purificación , Pirólisis , TermodinámicaRESUMEN
Image smearing significantly affects the accuracy of attitude determination of most star sensors. To ensure the accuracy and reliability of a star sensor under image smearing conditions, a novel directional integral method is presented for high-precision star spot location estimation to improve the accuracy of attitude determination. Simulations based on the orbit data of the challenging mini-satellite payload satellite were performed. Simulation results demonstrated that the proposed method exhibits high performance and good robustness, which indicates that the method can be applied effectively.
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Outcome evaluation is a cognitive process that plays an important role in our daily lives. In most paradigms utilized in the field of experimental psychology, outcome valence and outcome magnitude are the two major features investigated. The classical "independent coding model" suggests that outcome valence and outcome magnitude are evaluated by separate neural mechanisms that may be mapped onto discrete event-related potential (ERP) components: feedback-related negativity (FRN) and the P3, respectively. To examine this model, we presented outcome valence and magnitude sequentially rather than simultaneously. The results reveal that when only outcome valence or magnitude is known, both the FRN and the P3 encode that outcome feature; when both aspects of outcome are known, the cognitive functions of the two components dissociate: the FRN responds to the information available in the current context, while the P3 pattern depends on outcome presentation sequence. The current study indicates that the human evaluative system, indexed in part by the FRN and the P3, is more flexible than previous theories suggested.
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Mapeo Encefálico , Encéfalo/fisiología , Potenciales Evocados/fisiología , Retroalimentación Psicológica , Procesos Mentales/fisiología , Adulto , Análisis de Varianza , Conducta de Elección , Electroencefalografía , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Tiempo de Reacción , Adulto JovenRESUMEN
OBJECTIVE: To bring forward a new method for automatic measurement of the translation and rotation of the eye movement. METHODS: A centroid method, edge filter, and ellipse fitting were used to get the accurate position of the eye center. The rotation angle of the eye was determined by Fourier-Translation arithmetic operators. RESULTS: The simulation image test and initial clinical experiment obtained a good precision. CONCLUSION: This method can eliminate the influence of eyelid overlapping and illumination, which can measure the 3-dimensional eye movement accurately.