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1.
Nano Lett ; 24(15): 4602-4609, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38567988

RESUMEN

Oxygen vacancy (OV) engineering has been widely applied in different types of metal oxide-based photocatalytic reactions. Our study has shown that the redistributed OVs resulting from voids in CeO2 rods lead to significant differences in the band structure in space. The flat energy band within the highly crystallized bulk region hinders the recombination of photogenerated carrier pairs during the transfer process. The downward curved energy band in the surface region enhances the activation of the absorbents. Therefore, the localization of the band structure through crystal structure regionalization renders V-CeO2 capable of achieving efficient utilization of photogenerated carriers. Practically, the V-CeO2 rod shows a remarkable turnover number of 190.58 µmol g-1 h-1 in CO2 photoreduction, which is ∼9.4 times higher than that of D-CeO2 (20.46 µmol g-1 h-1). The designed modularization structure in our work is expected to provide important inspiration and guidance in coordinating the kinetic behavior of carriers in OV defect-rich photocatalysts.

2.
Front Nutr ; 11: 1440306, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39027657

RESUMEN

Aim: People with diabetes mellitus have a higher risk of dental caries than the general population. Diet is one of the most important factors affecting the risk of dental caries. This study aimed to evaluate the effect of dietary fiber to carbohydrate ratio (FCR) on the risk of dental caries in diabetic patients. Methods: Data of this cross-sectional study were extracted from the 2015-2020 cycle of the National Health and Nutrition Examination Survey (NHANES) database. FCR levels were divided into two categories based on the median (0.13). The outcomes were untreated dental caries and dental caries experience. The associations of FCR with untreated dental caries and dental caries experience were assessed using multivariable logistic regression analysis and reported as odds ratio (OR) and 95% confidence interval (CI). Stratified analyses were performed according to age (<65 and ≥ 65 years), gender (female and male), hypertension (yes and no), and the ratio of family income to poverty (PIR, <1 and ≥ 1). Results: A total of 2,412 patients diagnosed with diabetes were included, of whom 728 (30.18%) had untreated dental caries and 2,104 (87.23%) had dental caries experience. Patients with FCR ≥0.13 were correlated with lower odds of untreated dental caries (OR = 0.72, 95%CI: 0.52-0.99) and dental caries experience (OR = 0.63, 95%CI: 0.42-0.93) compared to patients with FCR <0.13. Stratified analyses demonstrated that patients with FCR ≥0.13 were found to be related to lower odds of untreated dental caries in those aged <65 years (OR = 0.64, 95%CI: 0.42-0.97), female (OR = 0.57, 95%CI: 0.35-0.93), with hypertension (OR = 0.66, 95%CI: 0.45-0.96), and PIR ≥1 (OR = 0.64, 95%CI: 0.42-0.99). Similar results to untreated dental caries were observed in the analysis of dental caries experience (p < 0.05). Conclusion: High levels of FCR may be associated with a lower risk of dental caries in patients with diabetes. Increasing the proportion of dietary fiber intake among diabetic patients may help prevent the occurrence of dental caries.

3.
Math Biosci Eng ; 21(1): 96-115, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38303415

RESUMEN

Network printers face increasing security threats from network attacks that can lead to sensitive information leakage and data tampering. To address these risks, we propose a novel Fibonacci-Diffie-Hellman (FIB-DH) encryption scheme using edge cloud collaboration. Our approach utilizes properties of third-order Fibonacci matrices combined with the Diffie-Hellman key exchange to encrypt printer data transmissions. The encrypted data is transmitted via edge cloud servers and verified by the receiver using inverse Fibonacci transforms. Our experiments demonstrate that the FIB-DH scheme can effectively improve printer data transmission security against common attacks compared to conventional methods. The results show reduced vulnerabilities to leakage and tampering attacks in our approach. This work provides an innovative application of cryptographic techniques to strengthen security for network printer communications.

4.
Materials (Basel) ; 17(13)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38998359

RESUMEN

Directed energy deposition (DED) is gaining widespread acceptance in various industrial applications since its unique manufacturing features allow the DED to print metallic parts with very complex geometries. However, DED inevitably generates a lot of internal pores which can limit the widespread applications of the DED technique. The current studies on DED porosity are mostly focused on analyzing pores' bulk-scale influences on mechanical properties and performances. Since DED pores have a micro-scale existence, with dimensions ranging from a few microns to several hundred microns, it is fundamental to explore the pores' influences on the micro-scale, including local mechanical properties, residual stress, and grains near pores. However, this important research direction has been neglected. The objective of this work is to fill the above gap in DED porosity research and acquire a fundamental understanding of the role of porosity on a microscopic scale. The authors used nanoindentation approaches to investigate internal pores' effects on mechanical properties and residual stress in local regions surrounding the pores. In addition, the grains near pores were observed through EBSD, and simulated with the Kinetic Monte Carlo model. The research findings can be provided for DED researchers and industrial practitioners as technical guidance. Most importantly, the research results can work as a good reference for tracing the source of bulk-scale mechanical performances and properties of DED parts with internal pores.

5.
Neuroimage Clin ; 41: 103556, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38134741

RESUMEN

It is posited that cognitive and affective dysfunction in patients with major depression disorder (MDD) may be caused by dysfunctional signal propagation in the brain. By leveraging dynamic causal modeling, we investigated large-scale directed signal propagation (effective connectivity) among distributed large-scale brain networks with 43 MDD patients and 56 healthy controls. The results revealed the existence of two mutual inhibitory systems: the anterior default mode network, auditory network, sensorimotor network, salience network and visual networks formed an "emotional" brain, while the posterior default mode network, central executive networks, cerebellum and dorsal attention network formed a "rational brain". These two networks exhibited excitatory intra-system connectivity and inhibitory inter-system connectivity. Patients were characterized by potentiated intra-system connections within the "emotional/sensory brain", as well as over-inhibition of the "rational brain" by the "emotional/sensory brain". The hierarchical architecture of the large-scale effective connectivity networks was then analyzed using a PageRank algorithm which revealed a shift of the controlling role of the "rational brain" to the "emotional/sensory brain" in the patients. These findings inform basic organization of distributed large-scale brain networks and furnish a better characterization of the neural mechanisms of depression, which may facilitate effective treatment.


Asunto(s)
Trastorno Depresivo Mayor , Humanos , Trastorno Depresivo Mayor/diagnóstico por imagen , Depresión , Vías Nerviosas/diagnóstico por imagen , Encéfalo , Mapeo Encefálico , Imagen por Resonancia Magnética/métodos
6.
Bioengineering (Basel) ; 11(2)2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38391609

RESUMEN

Single-view cone-beam X-ray luminescence computed tomography (CB-XLCT) has recently gained attention as a highly promising imaging technique that allows for the efficient and rapid three-dimensional visualization of nanophosphor (NP) distributions in small animals. However, the reconstruction performance is hindered by the ill-posed nature of the inverse problem and the effects of depth variation as only a single view is acquired. To tackle this issue, we present a methodology that integrates an automated restarting strategy with depth compensation to achieve reconstruction. The present study employs a fast proximal gradient descent (FPGD) method, incorporating L0 norm regularization, to achieve efficient reconstruction with accelerated convergence. The proposed approach offers the benefit of retrieving neighboring multitarget distributions without the need for CT priors. Additionally, the automated restarting strategy ensures reliable reconstructions without the need for manual intervention. Numerical simulations and physical phantom experiments were conducted using a custom CB-XLCT system to demonstrate the accuracy of the proposed method in resolving adjacent NPs. The results showed that this method had the lowest relative error compared to other few-view techniques. This study signifies a significant progression in the development of practical single-view CB-XLCT for high-resolution 3-D biomedical imaging.

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