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1.
Sensors (Basel) ; 24(9)2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38733060

RESUMO

Deep neural networks (DNNs) are increasingly important in the medical diagnosis of electrocardiogram (ECG) signals. However, research has shown that DNNs are highly vulnerable to adversarial examples, which can be created by carefully crafted perturbations. This vulnerability can lead to potential medical accidents. This poses new challenges for the application of DNNs in the medical diagnosis of ECG signals. This paper proposes a novel network Channel Activation Suppression with Lipschitz Constraints Net (CASLCNet), which employs the Channel-wise Activation Suppressing (CAS) strategy to dynamically adjust the contribution of different channels to the class prediction and uses the 1-Lipschitz's ℓ∞ distance network as a robust classifier to reduce the impact of adversarial perturbations on the model itself in order to increase the adversarial robustness of the model. The experimental results demonstrate that CASLCNet achieves ACCrobust scores of 91.03% and 83.01% when subjected to PGD attacks on the MIT-BIH and CPSC2018 datasets, respectively, which proves that the proposed method in this paper enhances the model's adversarial robustness while maintaining a high accuracy rate.


Assuntos
Algoritmos , Eletrocardiografia , Redes Neurais de Computação , Eletrocardiografia/métodos , Humanos , Processamento de Sinais Assistido por Computador
2.
Opt Express ; 31(3): 4129-4139, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785388

RESUMO

By using the flip-chip bonding technology, a high performances 3D-integrated silicon photonics receiver is demonstrated. The receiver consists of a high-speed germanium-silicon (Ge-Si) photodetector (PD) and a commercial linear transimpedance amplifiers (TIA). The overall 3 dB bandwidth of the receiver is around 38 GHz with appropriate gain. Based on this 3D-integrated receiver, the 56, 64, 90, 100 Gbit/s non-return-to-zero (NRZ) and 112, 128 Gbit/s four-level pulse amplitude (PAM-4) modulation clear openings of eye diagrams are experimentally obtained. The sensitivities of -10, -5.2 dBm and -6.6, -2.7 dBm were obtained for 112 Gbit/s NRZ and 160 Gbit/s PAM-4 at hard-decision forward err correction (HD-FEC,3.8 × 10-3) and KP4 forward err correction (KP4-FEC,2 × 10-4) threshold, respectively. Additionally, the lowest power consumption of this receiver is about 1.2 pJ/bit, which implies its huge potential for short-reach data center applications.

3.
Food Res Int ; 160: 111728, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36076417

RESUMO

Phenolic antioxidants are phytochemical components in wheat grains that provide a variety of potential health benefits. The metabolites and antioxidant activity of fresh, mature, and heat-treated, wheat grains with black, blue, purple, and white grain coats were identified by targeted and non-targeted metabolomics. The total phenolic (TPC) and flavonoid contents (TFC) and antioxidant activity (AOA) increased with the darkening of grain color, the general trend being black > purple > blue > white. Purple and black wheat are rich in rutin (3916 µg/kg and 3066 µg/kg, respectively) and peonidin-3-O-glucoside chloride (2595 µg/kg and 1740 µg/kg, respectively), while blue wheat is rich in luteolin (2076 µg/kg). In most cases, TPC, TFC, and AOA had the greatest values in fresh grains and the lowest values in mature grains. Using non-targeted metabolomics, a total of 866 metabolites were identified in the tested fresh wheat grains, 106 flavonoids and 39 phenolic acids. In total, the relative abundance of flavonoids in purple and black wheat was higher than in blue wheat, indicating a higher nutritional value of fresh black and purple grains. After heat processing, the content of most metabolites decreased in heat-treated purple grain, whereas heat treatment significantly increased the content of peonidin-3-O-glucoside chloride (2.27-fold) and cynaroside (12.01-fold). This study clarifies that seed coat color and processing treatments impact the metabolite contents and antioxidant activity of wheat grains, providing valuable information for improving the nutritional quality of food during processing.


Assuntos
Antioxidantes , Triticum , Antioxidantes/análise , Cloretos , Grão Comestível/química , Flavonoides/química , Temperatura Alta , Fenóis/análise , Triticum/química
4.
Front Nutr ; 9: 844337, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252312

RESUMO

Phenolic compounds are important bioactive phytochemicals with potential health benefits. In this study, integrated metabolomics and transcriptomics analysis was used to analyze the metabolites and differentially expressed genes in grains of two wheat cultivars (HPm512 with high antioxidant activity, and ZM22 with low antioxidant activity) during grain development. A total of 188 differentially expressed phenolic components, including 82 phenolic acids, 81 flavonoids, 10 lignans, and 15 other phenolics, were identified in the developing wheat grains, of which apigenin glycosides were identified as the primary flavonoid component. The relative abundance of identified phenolics showed a decreasing trend with grain development. Additionally, 51 differentially expressed phenolic components were identified between HPm512 and ZM22, of which 41 components, including 23 flavonoids, were up-regulated in HPm512. In developing grain, most of the identified differentially expressed genes involved in phenolic accumulation followed a similar trend. Integrated metabolomics and transcriptomics analysis revealed that certain genes encoding structural proteins, glycosyltransferase, and transcription factors were closely related to metabolite accumulation. The relatively higher accumulation of phenolics in HPm512 could be due to up-regulated structural and regulatory genes. A sketch map was drawn to depict the synthetic pathway of identified phenolics and their corresponding genes. This study enhanced the current understanding of the accumulation of phenolics in wheat grains. Besides, active components and their related genes were also identified, providing crucial information for the improvement of wheat's nutritional quality.

5.
J Sci Food Agric ; 101(15): 6167-6185, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34312865

RESUMO

Wheat (Triticum aestivum L.) is a widely cultivated crop and one of the most commonly consumed food grains in the world. It possesses several nutritional elements. Increasing attention to wheat grain phenolics bioactivity is due to the increasing demand for foods with natural antioxidants. To provide a comprehensive understanding of phenolics in wheat grain, this review first summarizes the phenolics' form and distribution and the phenolic components identified in wheat grain. In particular, the biosynthesis path for phenolics is discussed, identifying some candidate genes involved in the biosynthesis of phenolic acids and flavonoids. After discussing the methods for determining antioxidant activity, the effect of genotypes, environmental conditions, and cultivation systems on grain phenolic component content are explored. Finally, the bioavailability of phenolics under different food processing method are reported and discussed. Future research is recommended to increase wheat grain phenolic content by genetic engineering, and to improve its bioavailability through proper food processing. © 2021 Society of Chemical Industry.


Assuntos
Fenóis/química , Extratos Vegetais/química , Sementes/química , Triticum/crescimento & desenvolvimento , Manipulação de Alimentos , Genótipo , Fenóis/metabolismo , Extratos Vegetais/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Triticum/química , Triticum/genética , Triticum/metabolismo
6.
Plant Physiol Biochem ; 154: 66-74, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32526612

RESUMO

Monogalactosyl diacylglycerol (MGDG), the main component of the plastid membrane, is essential for chloroplast photosynthesis; however, little information is available about the function of MGDG synthases gene (TaMGD) in wheat grain. In this manuscript, three homologous genes were identified in wheat grain, and their functions were investigated by gene silencing and overexpression techniques. Three TaMGD homologous genes, TaMGD-6A, -6B, and -6D, located on chromosome 6A, 6B, and 6D, respectively, were isolated from common wheat. The transcription of TaMGD was detected in stems, roots, leaves and grains, and high levels of gene transcripts were detected in stems and leaves. Silencing of TaMGD in common wheat spikes resulted in a decrease in grain weight and starch content, and proteomic analysis showed that the differentially expressed proteins mainly included carbohydrate metabolism- and nucleic acid-related proteins. In comparison with wild-type, transgenic rice plants overexpressing TaMGD-6A and -6D showed an increase in thousand kernel weight, as well as an increase in the expression level of genes related to starch biosynthesis, whereas transgenic rice plants overexpressing TaMGD-6B showed increased grain yield and grain number per spike. The results of gene silencing and overexpression indicated that TaMGD plays an important role in wheat grain weight, which might be associated with carbohydrate metabolism. Hence, this study provides new insights regarding the role of TaMGD in wheat grain characteristics.


Assuntos
Galactolipídeos/biossíntese , Galactosiltransferases/genética , Proteínas de Plantas/genética , Triticum , Clonagem Molecular , Grão Comestível , Plantas Geneticamente Modificadas , Proteômica , Sementes/crescimento & desenvolvimento , Triticum/genética
7.
Ying Yong Sheng Tai Xue Bao ; 31(8): 2583-2592, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34494780

RESUMO

To provide basis for high-yield and high-efficiency of wheat production, with two wheat cultivars, 'Zhengmai 366' (strong gluten) and 'Bainong 207' (medium gluten), we investigated the effects of four nitrogen source types, ammonium chloride (NT1), calcium nitrate (NT2), urea (NT3) and calcium ammonium nitrate (NT4), applied under two water treatments, no irrigation (W1) and irrigation at jointing and heading stages (W2), on soil N-supplying capacity, grain yield and nitrogen utilization efficiency. The results showed that content of soil ammonium and nitrate at flowering stage decreased with increasing soil depths. Compared with the corresponding value of 'Zhengmai 366' under W1 treatment, W2 treatment decreased the contents of soil ammonium and nitrate in the 0-60 cm layer, and enzymes activities of urease, invertase and catalase by 10.0%, 13.3%, 7.5%, 2.8%, and 3.9%, respectively. For the two wheat cultivars, the content of ammo-nium was significantly higher under NT1 and NT3 treatments than that of others, while the content of nitrate under NT2 and NT3 treatments was significantly higher than that of others. Additionally, NT3 and NT4 treatments increased soil urease and invertase activities at the middle and later stages of grain filling. Compared with NT1 treatment, NT3 and NT4 fertilization increased grain yield and nitrogen use efficiency of cultivar 'Zhengmai 366' by 14.9% and 20.7%, 25.6% and 13.9%, under W2 treatment, respectively. Soil nitrate content in the 0-20 cm layer and the ammonium content in the 20-40 cm layer were positively correlated with wheat grain yield and nitrogen utilization efficiency. Under both water conditions, applying urea and calcium ammonium nitrate improved soil enzyme activity at the middle and later stages of grain filling, which was beneficial for wheat yield and nitrogen use efficiency.


Assuntos
Nitrogênio , Triticum , Irrigação Agrícola , Biomassa , Nitrogênio/análise , Solo , Água/análise
8.
Neuropsychiatr Dis Treat ; 14: 3037-3051, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519025

RESUMO

PURPOSE: This study was designed to explore the underlying mechanism of action for a Fuzheng Quxie Decoction (FQD) in Alzheimer's disease (AD), to validate its neuroprotective effects, and to provide experimental support for its predicted mechanism of action. METHODS: An integrative approach to network pharmacology was performed to predict the mechanism of action for treatment of AD with FQD. The predicted mechanism was validated in SAMP8 mice. RESULTS: With predicted putative FQD targets and a collection of AD-related genes, 245 possible regulatory targets of FQD were identified for the treatment of AD. Pathway-enrichment analysis for the possible regulatory targets indicated that vascular endothelial growth factor (VEGF) and VEGF-receptor signaling were pivotal in the treatment of AD with FQD. In vivo experiments confirmed the neuroprotective effect and the predicted mechanism of action for treatment of AD with FQD. CONCLUSION: This study contributes to an understanding of the neuroprotective effect of FQD and its potential mechanism of action for the treatment of AD.

9.
Artigo em Inglês | MEDLINE | ID: mdl-29422936

RESUMO

Hyperphosphorylation of the microtubule-associated protein, tau, is critical to the progression of Alzheimer's disease (AD). Fuzheng Quxie Decoction (FQD), a Chinese herbal complex, is an effective clinical formula used to treat AD. In the current study, we employed high-performance liquid chromatography and liquid chromatography tandem mass spectrometry to identify the components of FQD. Three major components (ginsenoside Rg1, ginsenoside Re, and coptisine) were detected in the brain of FQD-fed mice, indicating their ability to cross the blood-brain barrier. We further evaluated the efficacy of FQD on Senescence-Accelerated Mice Prone-8 (SAMP8) mice. FQD significantly ameliorated learning and memory deficits in SAMP8 mice on the Morris Water Maze, decreasing escape latency (p < 0.01) and increasing swim time within the original platform-containing quadrant (p < 0.05). Further, FQD increased the number of neurons and intraneuronal Nissl bodies in the hippocampal CA1 region. FQD also decreased the expression of phosphorylated tau protein and increased the expression of protein phosphatase 2A (PP2A) and the N-methyl-D-aspartate receptor subunit, NR2A (p < 0.01). Our results indicate that FQD improves the learning and memory ability of SAMP8 mice. Moreover, our findings suggest that the protective effect of FQD is likely mediated through an inhibition of hippocampal tau hyperphosphorylation via NMDAR/PP2A-associated proteins.

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