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1.
Small ; 20(25): e2309171, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38196296

RESUMEN

Various natural polymers offer sustainable alternatives to petroleum-based adhesives, enabling the creation of high-performance engineered materials. However, additional chemical modifications and complicated manufacturing procedures remain unavoidable. Here, a sustainable high-performance engineered composite that benefits from bonding strategies with multiple energy dissipation mechanisms dominated by chemical adhesion and mechanical interlocking is demonstrated via the fungal smart creative platform. Chemical adhesion is predominantly facilitated by the extracellular polymeric substrates and glycosylated proteins present in the fungal outer cell walls. The dynamic feature of non-covalent interactions represented by hydrogen bonding endows the composite with extensive unique properties including healing, recyclability, and scalable manufacturing. Mechanical interlocking involves multiple mycelial networks (elastic modulus of 2.8 GPa) binding substrates, and the fungal inner wall skeleton composed of chitin and ß-glucan imparts product stability. The physicochemical properties of composite (modulus of elasticity of 1455.3 MPa, internal bond strength of 0.55 MPa, hardness of 82.8, and contact angle of 110.2°) are comparable or even superior to those of engineered lignocellulosic materials created using petroleum-based polymers or bioadhesives. High-performance composite biofabrication using fungi may inspire the creation of other sustainable engineered materials with the assistance of the extraordinary capabilities of living organisms.


Asunto(s)
Hongos , Quitina/química , Módulo de Elasticidad
2.
Phys Rev Lett ; 132(5): 056702, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38364119

RESUMEN

We report a giant hysteretic spin Seebeck effect (SSE) anomaly with a sign reversal at magnetic fields much stronger than the coercive field in a (001)-oriented Tb_{3}Fe_{5}O_{12} film. The high-field SSE enhancement reaches 4200% at approximately 105 K over its weak-field value and presents a nonmonotonic dependence on temperature. The unexpected high-field hysteresis of SSE is found to be associated with a magnetic transition of double-umbrella spin texture in TbIG. Nearly parallel dispersion curves of magnons and acoustic phonons around this neoteric transition are supported by theoretical calculations, leading to a high density of field-tuned magnon polarons and consequently an extraordinarily large SSE. Our study provides insight into the evolution of magnon dispersions of double-umbrella TbIG and could potentially boost the efficiency of magnon-polarons SSE devices.

3.
Int J Legal Med ; 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38609696

RESUMEN

BACKGROUND: The offender-victim spatial relationship is crucial in reconstructing a crime scene. The study aims to evaluate the spatial relationship of performing slashing attacks on a dummy using a Chinese kitchen knife, and thus to establish a scientific basis for crime scene reconstruction. METHODS: Twenty-four participants (12 males and 12 females) slashed a dummy's neck or chest using a kitchen knife, and the kinematic data were obtained using a three-dimensional motion capture system. The spatial relationships among offender, knife, and victim during slashing attacks were analyzed. RESULTS: Slashing distance and occupancy area are significantly influenced by gender (all P < 0.05), with males having higher values than females. Body parts significantly influence bevel angle, offender and victim azimuth angles, slashing distance, relative slashing distance, and occupancy area (all P < 0.01), with slashing the chest resulting in larger values than slashing the neck. CONCLUSION: Gender and body position significantly influence the spatial relationships of slashing action. Our data indicate that males stand farther away and occupy a larger area during slashing attacks. When the chest is slashed, the wound orientation is more diagonal, the offender's standing position and slashing distance are farther, and the occupancy area is larger compared to the neck. The findings could help identify the spatial relationships among offender, knife, and victim, providing a scientific basis for criminal investigations and court trials.

4.
Molecules ; 29(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38611780

RESUMEN

This study investigates the synthesis of mesophase pitch using low-cost fluid catalytic cracking (FCC) slurry and waste fluid asphaltene (WFA) as raw materials through the co-carbonization method. The resulting mesophase pitch product and its formation mechanism were thoroughly analyzed. Various characterization techniques, including polarizing microscopy, softening point measurement, Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), were employed to characterize and analyze the properties and structure of the mesophase pitch. The experimental results demonstrate that the optimal optical texture of the mesophase product is achieved under specific reaction conditions, including a temperature of 420 °C, pressure of 1 MPa, reaction time of 6 h, and the addition of 2% asphaltene. It was observed that a small amount of asphaltene contributes to the formation of mesophase pitch spheres, facilitating the development of the mesophase. However, excessive content of asphaltene may cover the surface of the mesophase spheres, impeding the contact between them and consequently compromising the optical texture of the mesophase pitch product. Furthermore, the inclusion of asphaltene promotes polymerization reactions in the system, leading to an increase in the average molecular weight of the mesophase pitch. Notably, when the amount of asphaltene added is 2%, the mesophase pitch demonstrates the lowest ID/IG value, indicating superior molecular orientation and larger graphite-like microcrystals. Additionally, researchers found that at this asphaltene concentration, the mesophase pitch exhibits the highest degree of order, as evidenced by the maximum diffraction angle (2θ) and stacking height (Lc) values, and the minimum d002 value. Moreover, the addition of asphaltene enhances the yield and aromaticity of the mesophase pitch and significantly improves the thermal stability of the resulting product.

5.
Small ; 19(46): e2302827, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37403285

RESUMEN

High-performance porous materials with a low carbon footprint provide sustainable alternatives to petroleum-based lightweight foams and can help meet carbon neutrality goals. However, these materials generally face a trade-off between thermal management capabilities and structural strength. Here, a mycelium composite with a hierarchical porous structure, including both macro- and microscale pores, produced from multiple and advanced mycelial networks (elastic modulus of 1.2 GPa) binding loosely distributed sawdust is demonstrated. The morphological, biological, and physicochemical properties of the filamentous mycelium and composites are discussed in terms of how they are influenced by the mycelial system of the fungi and the way they interact with the substrate. The composite shows a porosity of 0.94, a noise reduction coefficient of 0.55 at a frequency range of 250-3000 Hz (for a 15 mm thick sample), a thermal conductivity of 0.042 W m-1  K-1 , and an energy absorption of 18 kJ m-3 at 50% strain. It is also hydrophobic, repairable, and recyclable. It is expected that the hierarchical porous structural composite with excellent thermal and mechanical properties can make a significant impact on the future development of highly sustainable alternatives to lightweight plastic foams.

6.
Int J Legal Med ; 137(1): 259-266, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35713717

RESUMEN

BACKGROUND: Slashing attack is one of the most common ways of committing a homicide. The purpose of this study was to evaluate the biomechanical characteristics of slashing different body parts of a dummy by young males and females using a Chinese kitchen knife and thus provide scientific evidence for criminal investigations and court trials. METHODS: A total of 12 male and 12 female college students participated in this study. Biomechanical parameters, including joint velocity, slashing velocity, slashing force, energy, and impulse, were evaluated when slashing the chest and the neck of a dummy using a Chinese kitchen knife. RESULTS: When slashing the neck or the chest of a dummy, male participants showed higher elbow and wrist velocities (21.2% and 28.5%, respectively) as well as higher knife velocity (33.6%), slashing velocity (25.3%), slashing force (23.3%), and energy (57.6%) compared to female participants (all p < 0.05). When slashing the chest, participants showed higher shoulder, elbow, and wrist velocities (31.9%, 12.7%, and 12.6%) as well as knife velocity (3.8%), slashing velocity (7.3%), and energy (23.2%) compared to slashing the neck (all p < 0.05), regardless of gender. CONCLUSION: Both gender and slashing position have great impact on biomechanical characteristics of the slashing movement. Our data indicate that when slashing using a Chinese kitchen knife, males may induce severer wounds than females, and slashing different body parts may generate different slashing velocity or energy. Compared to slashing position, gender may have greater influence on the biomechanical characteristics. Findings from this study may expand our knowledge about knife slashing attacks by Chinese kitchen knives as well as other knives with comparative heavy blades.


Asunto(s)
Homicidio , Cuerpo Humano , Humanos , Masculino , Femenino , Movimiento , Fenómenos Biomecánicos
7.
Fa Yi Xue Za Zhi ; 38(6): 702-708, 2022 Dec 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-36914385

RESUMEN

OBJECTIVES: To investigate the relationship between the perpetrator's sex, victim's position and slashing location as well as anthropometric parameters on distance and space required for slashing, to provide the theoretical basis for the judgment of whether the crime scene was consistent with the criminal activity space. METHODS: The kinematics data of 12 male and 12 female subjects slashing the neck of standing and supine mannequins as well as the chest of the standing mannequins with a kitchen knife were obtained by using a 3D motion capture system. The relationship between the perpetrator's sex-victim's position, the perpetrator's sex-slashing location, and anthropometric parameters and the distance and space required for the slashing were analyzed by two-factor repeated measures ANOVA and Pearson correlation analysis respectively. RESULTS: Compared with slashing the neck of supine mannequins, the distance (L) and normalized L (l) of slashing the neck of standing mannequins were greater, while vertical distance (LVR) and normalized LVR (lVR) of the knife side were smaller. Compared with slashing the neck of standing mannequins, the L and l slashing the chest of standing mannequins were greater, while LVR and lVR were smaller. Horizontal distance (LHR) and normalized LHR (lHR) of the knife side in males were greater than that in females. Height and arm length were positively correlated with L, LHR, and LVR when striking the standing mannequins. CONCLUSIONS: When slashing the neck of supine or standing victims, the slashing distance is shorter and the slashing height is greater. Furthermore, the distance and space required for slashing are correlate with anthropometric parameters.


Asunto(s)
Crimen , Captura de Movimiento , Humanos , Masculino , Femenino , Fenómenos Biomecánicos
8.
Powder Technol ; 390: 174-181, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36313254

RESUMEN

Computational analysis of virus dynamics provides a non-contact environment for the study of the vital object. Cluster modelling is an essential step to investigate the properties of a group of viruses, and an automatic approach is required for massive 3D data processing. The morphological complexity of individual virus limits the application of smooth function algorithms with a regular-shaped assumption. This paper proposed a voxel-based redistribution approach to generate the virus cluster with COVID-19 input automatically. Representative elementary volume analysis was performed to address the statistical influence from the digital sample size. Coordination number analysis and surface density measurement were conducted with COVID-19 input and spherical input for comparison. The proposed approach is in natural compatibility with the lattice Boltzmann method for fluid dynamics analysis. A virtual permeation simulation was performed with the COVID-19 cluster and spherical cluster to demonstrate the necessity to include spike protein structure in the cluster modelling.

9.
Curr Genet ; 66(1): 43-49, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31209564

RESUMEN

Bacterial cell division is a highly controlled process regulated accurately by a diverse array of proteins spatially and temporally working together. Among these proteins, FtsZ is recognized as a cytoskeleton protein because it can assemble into a ring-like structure called Z-ring at midcell. Z-ring recruits downstream proteins, thus forming a multiprotein complex termed the divisome. When the Z-ring scaffold is established and the divisome matures, peptidoglycan (PG) biosynthesis and chromosome segregation are triggered. In this review, we focus on multiple interactions between FtsZ and its accessory proteins in bacterial cell cytokinesis, including FtsZ localization, Z-ring formation and stabilization, PG biosynthesis, and chromosome segregation. Understanding the interactions among these proteins may help discover superior targets on treating bacterial infectious diseases.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Citocinesis/fisiología , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , División Celular , Proteínas del Citoesqueleto/química , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Metabolismo Energético , Unión Proteica , Estabilidad Proteica , Transporte de Proteínas , Relación Estructura-Actividad
11.
Planta Med ; 84(3): 168-175, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28938496

RESUMEN

Previous studies have shown that icaritin (ICT) has significant protective effects on immune thrombocytopenia (ITP), and the present study aimed to discuss the mechanism of this protective effect from the aspect of regulating T-cell polarization by an antibody-induced ITP mice model. Mice were given rat anti-mouse CD41 antibody (MWReg30) by intraperitoneal injection for 7 d to produce ITP model. At the same time, ICT was administrated at 10 mg/kg/d orally for 9 d. Peripheral blood platelets were counted by hematology analyzer. Spleen index was also tested. Spleen T-helper cell (Th), cytotoxic T-cell (CTL), Th1, Th2, Th17, regulatory T-cell (Treg), and follicular helper T-cell (Tfh) were quantified by flow cytometry. Serum Th1/Th2/Th17 cytokines were tested by mouse Th1/Th2/Th17 cytometric bead array (CBA) kit and transforming growth factor beta (TGF-ß) were analyzed by enzyme-linked immunosorbent assay (ELISA) kit. The results indicated that ICT (10 mg/kg) protected against MWReg30-induced ITP, as evidenced by increased blood platelets and decreased spleen index. In addition, the imbalance of Th/CTL in ITP mice spleen was regulated by ICT. Meanwhile, ICT inhibited Th1, Th17, and Tfh and improved Th2 and Treg in ITP mice spleen. Furthermore, the results of CBA and ELISA suggested that ICT decreased serum Th1- and Th17-related cytokines and increased Th2 cytokines, as well as promoted the release of TGF-ß. These results demonstrated that the protective effect of ICT on ITP was mediated by regulating T-cell polarization.


Asunto(s)
Flavonoides/uso terapéutico , Sustancias Protectoras/uso terapéutico , Linfocitos T/efectos de los fármacos , Trombocitopenia/tratamiento farmacológico , Animales , Anticuerpos/inmunología , Enfermedades Autoinmunes/tratamiento farmacológico , Recuento de Linfocito CD4 , Citocinas/sangre , Modelos Animales de Enfermedad , Ratones , Glicoproteína IIb de Membrana Plaquetaria/inmunología , Bazo/citología , Bazo/efectos de los fármacos , Trombocitopenia/sangre , Trombocitopenia/inmunología , Factor de Crecimiento Transformador beta/sangre
12.
Immunopharmacol Immunotoxicol ; 40(1): 25-34, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29077519

RESUMEN

CONTEXT: Icaritin (ICT), an intestinal metabolite of prenylflavonoids from Herba Epimedii, has been known to regulate many immune processes. But there are little studies of ICT on hematopoietic function. OBJECTIVE: We aimed to investigate the improvement of ICT on hematopoietic function in cyclophosphamide (CTX)-induced myelosuppression mice. METHODS: Mice were given CTX (50 mg/kg) by i.p. for five days to produce bone marrow depression model. 48 h after last treated with CTX, ICT was administrated at 10 mg/kg/d by p.o. for five days. Blood routine, body weight, thymus index and spleen index were tested. The bone marrow hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs), cell cycle and apoptosis of HSCs were quantified by flow cytometry. The bone marrow nucleated cells were counted by an automated cell counter. The histology of femoral bone was examined by Haemotoxylin and Eosin (H&E) staining. Serum erythropoietin (EPO), granulocyte colony-stimulating factor (G-CSF) and thyroperoxidase (TPO) were tested by ELISA kit. RESULTS: ICT (10 mg/kg) protected against CTX-induced myelosuppression, is evidenced by increased blood cell numbers, body weight, thymus index, spleen index and improved femoral bone morphology. ICT corrected the reduction of bone marrow HSCs and HPCs, promoted bone marrow HSCs entering the proliferative cycle phase and prevented cells proceeding to the apoptosis phase. Meanwhile, ICT increased the release of G-CSF and TPO in model mice serum. CONCLUSION: These results demonstrated that ICT improves myelosuppression by improving bone marrow hematopoietic microenvironment, promoting the proliferation and differentiation of HSCs, inhibiting the apoptosis of HSCs and stimulating the expression of G-CSF and TPO.


Asunto(s)
Enfermedades de la Médula Ósea , Ciclofosfamida/efectos adversos , Flavonoides/farmacología , Hematopoyesis/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Nicho de Células Madre/efectos de los fármacos , Animales , Enfermedades de la Médula Ósea/inducido químicamente , Enfermedades de la Médula Ósea/metabolismo , Enfermedades de la Médula Ósea/patología , Ciclofosfamida/farmacología , Células Madre Hematopoyéticas/patología , Masculino , Ratones
13.
Biomacromolecules ; 17(6): 2080-6, 2016 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-27181113

RESUMEN

Antimicrobial resistance is an increasingly problematic issue in the world and there is a present and urgent need to develop new antimicrobial therapies without drug resistance. Antibacterial polymers are less susceptible to drug resistance but they are prone to inducing serious side effects due to high positive charge. Herein we report a peptide-grafted hyperbranched polymer which can self-assemble into unusual nanosheets with highly effective intrinsically antibacterial activity but weak positive charges (+ 6.1 mV). The hyperbranched polymer was synthesized by sequential Michael addition-based thiol-ene and free radical mediated thiol-ene reactions, and followed by ring-opening polymerization of N-carboxyanhydrides (NCAs). The nanosheet structure was confirmed by transmission electron microscopy (TEM) and atomic force microscopy (AFM) studies. Furthermore, a novel "wrapping and penetrating" antibacterial mechanism of the nanosheets was revealed by TEM and it is the key to significantly decrease the positive charges but have a very low minimum inhibitory concentration (MIC) of 16 µg mL(-1) against typical Gram-positive and Gram-negative bacteria. Overall, our synthetic strategy demonstrates a new insight for synthesizing antibacterial nanomaterials with weak positive charges. Moreover, the unique antibacterial mechanism of our nanosheets may be extended for designing next-generation antibacterial agents without drug resistance.


Asunto(s)
Antibacterianos/síntesis química , Nanoestructuras/química , Péptidos/química , Polímeros/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Antibacterianos/toxicidad , Supervivencia Celular , Células Cultivadas , Capacidad Eléctrica , Eritrocitos/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión , Polímeros/química , Polímeros/farmacología , Polímeros/toxicidad , Propiedades de Superficie
14.
Bioconjug Chem ; 26(4): 725-34, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25721382

RESUMEN

Cancer patients after chemotherapy may also suffer bacterial attack due to badly decreased immunity. Although with high bacterial efficacy, conventional antibiotics are prone to inducement of drug resistance and may be not suitable for some cancer patients. In contrast, antibacterial peptides are highly effective in inhibiting bacteria without inducing resistance in pathogens. Presented in this article is a novel kind of highly effective antibacterial peptide-based biocompatible and biodegradable block copolymer vesicle. The copolymer is poly(ε-caprolactone)-block-poly[phenylalanine-stat-lysine-stat-(lysine-folic acid)] [PCL19-b-poly[Phe12-stat-Lys9-stat-(Lys-FA)6]], which can self-assemble into vesicles in aqueous solution. The biocompatible and biodegradable PCL forms the vesicle membrane, whereas the poly[Phe12-stat-Lys9-stat-(Lys-FA)6] block constitutes the vesicle coronas. Compared to the individual polymer chains, the vesicles showed enhanced antibacterial activities against both Gram-positive and Gram-negative bacteria (16 µg mL(-1)) due to the locally concentrated antibacterial poly[Phe12-stat-Lys9-stat-(Lys-FA)6] coronas, which may avoid the inducement of antibiotic-resistant bacteria and side effects of multidrug interactions. Furthermore, folic acid is introduced into the vesicle coronas for potential further applications such as cancer-targeted drug delivery. Moreover, the amino groups can be further functionalized when necessary. This low cytotoxic, biocompatible, biodegradable, and antibacterial vesicle (without antibiotic resistance) may benefit patients after tumor surgery because it is highly anti-inflammatory, and it is possible to deliver the anticancer drug to tumor cells simultaneously.


Asunto(s)
Antibacterianos/síntesis química , Péptidos Catiónicos Antimicrobianos/química , Portadores de Fármacos/síntesis química , Ácido Fólico/química , Poliésteres/química , Antibacterianos/farmacología , Antibióticos Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Materiales Biocompatibles , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Doxorrubicina/farmacología , Portadores de Fármacos/farmacología , Liberación de Fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Humanos , Cinética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Propiedades de Superficie
15.
Heliyon ; 10(7): e28035, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38560129

RESUMEN

Objective: This study was aimed to explore the correlation between METTL3 polymorphisms and susceptibility to knee osteoarthritis (KOA). Methods: The relationship of five single nucleotide polymorphisms (SNPs) in the METTL3 gene with the susceptibility of KOA was analyzed through multinomial logistic regression analysis in this a case-control study. Genotyping was performed on 228 KOA patients and 252 unaffected individuals from South China based on the TaqMan method. The MDR software (version 3.0.2) was utilized for the analysis of SNP interactions. Results: Out of the five SNPs examined, the T > G change in the METTL3 gene at the rs1061026 locus increased the risk of KOA, while rs1139130 A > G and rs1263802 C > T variants were found to be linked with a reduced risk of developing KOA with statistical significance. The rs1061027 A > C and rs1263801 C > G variants did not show significant association (p>0.05). The rs1061026 TG/GG genotype showed a significant correlation with an increased risk of KOA in the following subgroups: the males, individuals with a BMI ranging from 24 to 28, smokers, those who were not engaged in physical exercise (PE), patients who had experienced KOA symptoms for eight years or longer, and those without a family history of the disease or reported swelling. On the other hand, the rs1139130 AG/GG genotype demonstrated a protective effect against KOA among the females, individuals with a BMI greater than or equal to 24, a unilateral KOA, or a KOA duration of 8 years or less, non-smokers, non-alcohol drinkers, those who were not engaged in PE, and those who had no injury or family history, or no experience of knee swelling. Additionally, it was observed that the rs1263802 CT/TT genotypes showed a protective effect among patients without a history of injury. Furthermore, individuals with the haplotypes GAT, GGC, TAT, and TGC were found to have a significantly lower susceptibility to KOA compared to the reference haplotype TAC. Conclusions: The METTL3 gene variant rs1061026 could increase the risk of KOA, whereas the variants of rs1139130 as well as rs1263802 might exert a protective effect against KOA. These variants could potentially function as susceptibility markers for KOA among the population from South China.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2280-5, 2013 Aug.
Artículo en Zh | MEDLINE | ID: mdl-24159894

RESUMEN

Spectral calibration must be carried out in order to determine its central wavelength and half-wave band width of each pixel before the usage of imaging spectrometer. But it was found out that these parameters vary as environment changes. The present paper studies the effect based on test field data. The authors analyzed the optical structure and compared the working environmental parameters. Then a theoretical model is established and the influences of vibration, distortion and temperature parameters are evaluated. The theoretical model and the caculation results are in good consistency, which testifies the theoretical model. This research will shed some light on the high accuracy spectral calibration of the grating based imaging spectrometer and its manufacture.

17.
Micromachines (Basel) ; 14(10)2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37893396

RESUMEN

The lattice metamaterial has attracted extensive attention due to its excellent specific strength, energy absorption capacity, and strong designability of the cell structure. This paper aims to explore the functional nickel plating on the basis of biomimetic-designed lattice structures, in order to achieve higher stiffness, strength, and energy absorption characteristics. Two typical structures, the body-centered cubic (BCC) lattice and the bioinspired hierarchical circular lattice (HCirC), were considered. The BCC and HCirC lattice templates were prepared based on DLP (digital light processing) 3D printing. Based on this, chemical plating, as well as the composite plating of chemical plating followed by electroplating, was carried out to prepare the corresponding nickel-plated lattice structures. The mechanical properties and deformation failure mechanisms of the resin-based lattice, chemically plated lattice, and composite electroplated lattice structures were studied by using compression experiments. The results show that the metal coating can significantly improve the mechanical properties and energy absorption capacity of microlattices. For example, for the HCirC structure with the loading direction along the x-axis, the specific strength, specific stiffness, and specific energy absorption after composite electroplating increased by 546.9%, 120.7%, and 2113.8%, respectively. The shell-core structure formed through composite electroplating is the main factor for improving the mechanical properties of the lattice metamaterial. In addition, the functional nickel plating based on biomimetic structure design can further enhance the improvement space of mechanical performance. The research in this paper provides insights for exploring lighter and stronger lattice metamaterials and their multifunctional applications.

18.
Artículo en Inglés | MEDLINE | ID: mdl-37698959

RESUMEN

Multimodal data play an important role in the diagnosis of brain diseases. This study constructs a whole-brain functional connectivity network based on functional MRI data, uses non-imaging data with demographic information to complement the classification task for diagnosing subjects, and proposes a multimodal and across-site WL-DeepGCN-based method for classification to diagnose autism spectrum disorder (ASD). This method is used to resolve the existing problem that deep learning ASD identification cannot efficiently utilize multimodal data. In the WL-DeepGCN, a weight-learning network is used to represent the similarity of non-imaging data in the latent space, introducing a new approach for constructing population graph edge weights, and we find that it is beneficial and robust to define pairwise associations in the latent space rather than the input space. We propose a graph convolutional neural network residual connectivity approach to reduce the information loss due to convolution operations by introducing residual units to avoid gradient disappearance and gradient explosion. Furthermore, an EdgeDrop strategy makes the node connections sparser by randomly dropping edges in the raw graph, and its introduction can alleviate the overfitting and oversmoothing problems in the DeepGCN training process. We compare the WL-DeepGCN model with competitive models based on the same topics and nested 10-fold cross-validation show that our method achieves 77.27% accuracy and 0.83 AUC for ASD identification, bringing substantial performance gains.


Asunto(s)
Trastorno del Espectro Autista , Humanos , Trastorno del Espectro Autista/diagnóstico , Encéfalo/diagnóstico por imagen , Redes Neurales de la Computación
19.
PLoS One ; 18(12): e0295621, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38064474

RESUMEN

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition whose current psychiatric diagnostic process is subjective and behavior-based. In contrast, functional magnetic resonance imaging (fMRI) can objectively measure brain activity and is useful for identifying brain disorders. However, the ASD diagnostic models employed to date have not reached satisfactory levels of accuracy. This study proposes the use of MAACNN, a method that utilizes multi-view convolutional neural networks (CNNs) in conjunction with attention mechanisms for identifying ASD in multi-scale fMRI. The proposed algorithm effectively combines unsupervised and supervised learning. In the initial stage, we employ stacked denoising autoencoders, an unsupervised learning method for feature extraction, which provides different nodes to adapt to multi-scale data. In the subsequent stage, we perform supervised learning by employing multi-view CNNs for classification and obtain the final results. Finally, multi-scale data fusion is achieved by using the attention fusion mechanism. The ABIDE dataset is used to evaluate the model we proposed., and the experimental results show that MAACNN achieves superior performance with 75.12% accuracy and 0.79 AUC on ABIDE-I, and 72.88% accuracy and 0.76 AUC on ABIDE-II. The proposed method significantly contributes to the clinical diagnosis of ASD.


Asunto(s)
Trastorno del Espectro Autista , Encefalopatías , Trastornos del Neurodesarrollo , Humanos , Trastorno del Espectro Autista/diagnóstico por imagen , Redes Neurales de la Computación , Algoritmos , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen
20.
RSC Adv ; 13(27): 18676-18689, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37346963

RESUMEN

For the preparation of high-performance pitch-based carbon fibers and other carbon materials, mesophase pitch serves as a high-quality precursor. Since FCC (Fluid Catalytic Cracking) oil slurry is abundant in aromatic hydrocarbons and saturated hydrocarbons (about 95% in total), it has become an ideal choice for developing new carbon material products. This paper details the research progress of preparing mesophase asphalt with FCC oil slurry as a raw material from perspectives including the preparation method of synthesizing mesophase asphalt from FCC oil slurry, the impact factors of the formation process of mesophase asphalt and the industrial application of mesophase asphalt.

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