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1.
Sensors (Basel) ; 24(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38676066

RESUMO

Simultaneous transmit and receive wireless communications have been highlighted for their potential to double the spectral efficiency. However, it is necessary to mitigate self-interference (SI). Considering both the SI channel and remote transmission (RT) channel need to be estimated before equalizing the received signal, we propose two adaptive algorithms for linear and nonlinear self-interference cancellation (SIC), based on a multi-layered joint channel estimator structure. The proposed algorithms estimate the RT channel while performing SIC, and the multi-layered structure ensures improved performance across various interference-to-signal ratios. The M-estimate function enhances the robustness of the algorithm, allowing it to converge even when affected by impulsive noise. For nonlinear SIC, this paper introduces an adaptive algorithm based on generalized Hammerstein polynomial basis functions. The simulation results indicate that this approach achieves a better convergence speed and normalized mean squared difference compared to existing SIC methods, leading to a lower system bit error rate.

3.
J Phys Chem Lett ; 15(2): 556-564, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38198134

RESUMO

The human brain efficiently processes only a fraction of visual information, a phenomenon termed attentional control, resulting in energy savings and heightened adaptability. Translating this mechanism into artificial visual neurons holds promise for constructing energy-efficient, bioinspired visual systems. Here, we propose a self-rectifying artificial visual neuron (SEVN) based on a NiO/Ga2O3 bipolar heterojunction with attentional control on patterns with a target color. The device exhibits short-term potentiation (STP) with quantum point contact (QPC) traits at low bias and transitions to long-term potentiation (LTP) at high bias, particularly facilitated by electron capture in deep defects upon ultraviolet (UV) exposure. With the utilization of two wavelengths of light upon the target and interference part of CAPTCHA to simulate top-down attentional control, the recognition accuracy is enhanced from 74 to 84%. These findings have the potential to augment the visual capability of neuromorphic systems with implications for diverse applications, including cybersecurity, healthcare, and machine vision.


Assuntos
Encéfalo , Sinapses , Humanos , Sinapses/fisiologia , Neurônios
4.
Int J Mol Sci ; 24(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37833903

RESUMO

Albino seedlings that arise during seed reproduction can have a significant impact on plant growth and breeding. In this research, we present the first report of albino occurrences in the seed reproduction process of Prunus salicina and describe the cytological, physiological, and transcriptomic changes observed in albino seedlings. The albino seedlings which were observed in several plum cultivars exhibited abnormal chloroplast ultrastructure and perturbed stomatal structure. Compared to normal seedlings, the photosynthetic pigment contents in albino seedlings decreased by more than 90%, accompanied by significant reductions in several chlorophyll fluorescence parameters. Furthermore, substantially changed photosynthetic parameters indicated that the photosynthetic capacity and stomatal function were impaired in albino seedlings. Additionally, the activities of the antioxidant enzyme were drastically altered against the background of higher proline and lower ascorbic acid in leaves of albino seedlings. A total of 4048 differentially expressed genes (DEGs) were identified through transcriptomic sequencing, and the downregulated DEGs in albino seedlings were greatly enriched in the pathways for photosynthetic antenna proteins and flavonoid biosynthesis. GLK1 and Ftsz were identified as candidate genes responsible for the impaired chloroplast development and division in albino seedlings. Additionally, the substantial decline in the expression levels of examined photosystem-related chloroplast genes was validated in albino seedlings. Our findings shed light on the intricate physiological and molecular mechanisms driving albino plum seedling manifestation, which will contribute to improving the reproductive and breeding efforts of plums.


Assuntos
Prunus domestica , Perfilação da Expressão Gênica , Fotossíntese/genética , Melhoramento Vegetal , Folhas de Planta/genética , Prunus domestica/genética , Plântula/metabolismo , Transcriptoma , China
5.
J Agric Food Chem ; 71(32): 12346-12356, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37539957

RESUMO

The flavor and taste of Lonicerae japonicae flos (LJF) products are heavily influenced by geographical origin. Tracing the geographical origin is an important aspect of LJF quality assessment. Here, DNA methylation analysis coupled with chemometrics revealed that, in 10 CpG islands upstream of genes in the chlorogenic acid and iridoid biosynthetic pathways, DNA methylation differences appear close association with LJF geographical origin. DNA methylation status in these CpG islands was determined using the cationic conjugated polymer fluorescence resonance energy transfer method. As a result, LJFs from 39 geographical origins were classified into four groups corresponding to Northern China, Central Plain of China, Southeast China, and Western China, according to cluster analysis and principal component analysis. Our findings contribute to an understanding of the modulation of LJF taste and can assist in understanding how DNA methylation in LJF varies with geographical origin.


Assuntos
Metilação de DNA , Transferência Ressonante de Energia de Fluorescência , Cátions/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Metabolômica , Epigênese Genética , China
6.
Nat Commun ; 14(1): 4459, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491528

RESUMO

Avalanche and surge robustness involve fundamental carrier dynamics under high electric field and current density. They are also prerequisites of any power device to survive common overvoltage and overcurrent stresses in power electronics applications such as electric vehicles, electricity grids, and renewable energy processing. Despite tremendous efforts to develop the next-generation power devices using emerging ultra-wide bandgap semiconductors, the lack of effective bipolar doping has been a daunting obstacle for achieving the necessary robustness in these devices. Here we report avalanche and surge robustness in a heterojunction formed between the ultra-wide bandgap n-type gallium oxide and the wide-bandgap p-type nickel oxide. Under 1500 V reverse bias, impact ionization initiates in gallium oxide, and the staggered band alignment favors efficient hole removal, enabling a high avalanche current over 50 A. Under forward bias, bipolar conductivity modulation enables the junction to survive over 50 A surge current. Moreover, the asymmetric carrier lifetime makes the high-level carrier injection dominant in nickel oxide, enabling a fast reverse recovery within 15 ns. This heterojunction breaks the fundamental trade-off between robustness and switching speed in conventional homojunctions and removes a key hurdle to advance ultra-wide bandgap semiconductor devices for power industrial applications.

7.
Front Plant Sci ; 14: 1159223, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123828

RESUMO

Background: Pineapple is the only commercially grown fruit crop in the Bromeliaceae family and has significant agricultural, industrial, economic, and ornamental value. GRF (growth-regulating factor) proteins are important transcription factors that have evolved in seed plants (embryophytes). They contain two conserved domains, QLQ (Gln, Leu, Gln) and WRC (Trp, Arg, Cys), and regulate multiple aspects of plant growth and stress response, including floral organ development, leaf growth, and hormone responses. The GRF family has been characterized in a number of plant species, but little is known about this family in pineapple and other bromeliads. Main discoveries: We identified eight GRF transcription factor genes in pineapple, and phylogenetic analysis placed them into five subfamilies (I, III, IV, V, VI). Segmental duplication appeared to be the major contributor to expansion of the AcGRF family, and the family has undergone strong purifying selection during evolution. Relative to that of other gene families, the gene structure of the GRF family showed less conservation. Analysis of promoter cis-elements suggested that AcGRF genes are widely involved in plant growth and development. Transcriptome data and qRT-PCR results showed that, with the exception of AcGRF5, the AcGRFs were preferentially expressed in the early stage of floral organ development and AcGRF2 was strongly expressed in ovules. Gibberellin treatment significantly induced AcGRF7/8 expression, suggesting that these two genes may be involved in the molecular regulatory pathway by which gibberellin promotes pineapple fruit expansion. Conclusion: AcGRF proteins appear to play a role in the regulation of floral organ development and the response to gibberellin. The information reported here provides a foundation for further study of the functions of AcGRF genes and the traits they regulate.

8.
J Phys Chem Lett ; 13(30): 7094-7099, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35900195

RESUMO

Surface treatment after dry etching is vital to enhance the surface quality of the material and thus improve device performance. In this Letter, we identified the majority surface states induced by the dry etching of ß-Ga2O3 and optimized surface treatments to suppress these electrically active defects with the improved performance of Schottky barrier diodes. Transient spectroscopies suggested that the majority traps (EC-0.75 eV) related to divacancies (VGa-VO) were enhanced in the concentration of 3.37 × 1014 cm-3 by dry etching and reduced to 0.90 × 1014 cm-3 by the combined means of oxygen annealing and piranha solution treatment. The trap evolution is supported by the suppressed donor-acceptor pair radiative recombination related to oxygen vacancies, the improved carrier transport (negligible hysteresis current-voltage and unity ideality factor), and the reduced surface band bending. These findings provide a straightforward strategy to improve surface quality for the further performance improvement of Ga2O3 power diodes.

9.
Sci Rep ; 11(1): 23649, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880328

RESUMO

Intrahepatic cholangiocarcinoma (CHOL) remains a rare malignancy, ranking as the leading lethal primary liver cancer worldwide. However, the biological functions of integrator complex subunit 8 (INTS8) in CHOL remain unknown. Thus, this research aimed to explore the potential role of INTS8 as a novel diagnostic or therapeutic target in CHOL. Differentially expressed genes (DEGs) in two Gene Expression Omnibus (GEO) datasets were obtained by the "RRA" package in R software. The "maftools" package was used to visualize the CHOL mutation data from The Cancer Genome Atlas (TCGA) database. The expression of INTS8 was detected by performing quantitative reverse transcription-PCR (qRT-PCR) and immunohistochemistry in cell lines and human samples. The association between subtypes of tumour-infiltrating immune cells (TIICs) and INTS8 expression in CHOL was determined by using CIBERSORT tools. We evaluated the correlations between INTS8 expression and mismatch repair (MMR) genes and DNA methyltransferases (DNMTs) in pan-cancer analysis. Finally, the pan-cancer prognostic signature of INTS8 was identified by univariate analysis. We obtained the mutation landscapes of an RRA gene set in CHOL. The expression of INTS8 was upregulated in CHOL cell lines and human CHOL samples. Furthermore, INTS8 expression was closely associated with a distinct landscape of TIICs, MMR genes, and DNMTs in CHOL. In addition, the high INTS8 expression group presented significantly poor outcomes, including overall survival (OS), disease-specific survival (DSS) and disease-free interval (DFI) (p < 0.05) in pan-cancer. INTS8 contributes to the tumorigenesis and progression of CHOL. Our study highlights the significant role of INTS8 in CHOL and pan-cancers, providing a valuable molecular target for cancer research.


Assuntos
Neoplasias dos Ductos Biliares/terapia , Colangiocarcinoma/terapia , Biologia Computacional/métodos , Subunidades Proteicas/fisiologia , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , Subunidades Proteicas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Pancreas ; 50(8): 1202-1211, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34714285

RESUMO

OBJECTIVE: The intestinal barrier injury caused by severe acute pancreatitis (SAP) can induce enterogenous infection, further aggravating the inflammatory reactions and immune responses. This study aimed to test the hypothesis that emodin protects the intestinal function and is involved in the immune response in SAP. METHODS: The network pharmacology was established using the Swiss target prediction and pathway enrichment analysis. The SAP mice model was induced by cerulein (50 µg/kg) and lipopolysaccharide (10 mg/kg) hyperstimulation. The pharmacological effect of emodin in treating SAP was evaluated at mRNA and protein levels by various methods. RESULTS: The network analysis provided the connectivity between the targets of emodin and the intestinal barrier-associated proteins and predicted the BAX/Bcl-2/caspase 3 signaling pathway. Emodin alleviated the pathological damages to the pancreas and intestine and reduced the high concentrations of serum amylase and cytokines in vivo. Emodin increased the expression of intestinal barrier-related proteins and reversed the changes in the apoptosis-related proteins in the intestine. Simultaneously, emodin regulated the ratio of T helper type 1 (TH1), TH2, TH17, γδ T cells, and interferon γ/interleukin 17 producing γδ T cells. CONCLUSIONS: These findings partly verified the mechanism underlying the regulation of the intestinal barrier and immune response by emodin.


Assuntos
Apoptose/efeitos dos fármacos , Emodina/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Pancreatite/tratamento farmacológico , Pancreatite/imunologia , Animais , Modelos Animais de Doenças , Camundongos
11.
Bioengineered ; 11(1): 628-639, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33034242

RESUMO

Loganin, a major bioactive iridoid glycoside derived from Cornus officinalis, exerts different beneficial biological properties. Recently, loganin has been reported to exhibit potential anti-inflammatory effects in the intestinal tissues, while the detailed mechanisms remain elusive. This study aimed to investigate whether loganin could inhibit the inflammatory response in dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) and to explore possible molecular mechanisms involved in this process. Results showed that oral administration of loganin significantly decreased body weight loss, disease activity index, colon shortening, myeloperoxidase (MPO) activity and pathologic abnormalities in UC mice. Loganin obviously inhibited the mRNA and protein levels of IL-6, TNF-α and IL-1ß in colon tissues from UC mice. Furthermore, loganin remarkably reduced macrophage M1 polarization in UC mice evidenced by reduced the number of F4/80 and iNOS dual-stained M1 macrophages, and the expression of M1 macrophage-related pro-inflammatory chemokines/cytokines including MCP-1, CXCL10 as well as COX-2. Further investigation showed that loganin upregulated the mRNA and protein levels of Sirt1, with the inhibition of NF-κB-p65 acetylation in colon tissues from UC mice. Moreover, Sirt1-specific inhibitor Ex527 administration abolished the anti-inflammatory and anti-macrophage M1 polarization effects of loganin in UC. Thus, loganin could inhibit M1 macrophage-mediated inflammation and modulate Sirt1/NF-κB signaling pathway to attenuate DSS-induced UC. Loganin was considered as a viable natural strategy in the treatment of UC.[Figure: see text].


Assuntos
Colite Ulcerativa/metabolismo , Iridoides/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , NF-kappa B/metabolismo , Sirtuína 1/metabolismo , Animais , Western Blotting , Citocinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos
12.
Opt Express ; 27(14): 19102-19118, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503674

RESUMO

We present an accelerated algorithm for calculating the near-field of non-uniform sparse apertures with non-uniform fast Fourier transform (NUFFT). The distances of the adjacent units in non-uniform sparse apertures are unequal and larger than half a wavelength. The near-field of apertures can be calculated by the angular spectrum method and the convolution methods, and according to the different convolution kernels, the convolution methods can be divided as the Fresnel kernel convolution and the Rayleigh-Sommerfeld kernel convolution. The Fresnel kernel is the approximation of the Rayleigh-Sommerfeld kernel in the far regions of the near-field zone. In uniform apertures, the three methods can be accelerated by fast Fourier transform (FFT). However, FFT should be replaced by NUFFT for non-uniform sparse apertures. The simulation results reveal that the Rayleigh-Sommerfeld convolution with NUFFT (RS-NUFFT) can be applied to all aperture sizes, distributions and near-field distances. After investigating the error sources in RS-NUFFT, the techniques (padding zeros for apertures, increasing sampling rate for the convolution kernel) are developed for increasing the calculation accuracy of RS-NUFFT.

13.
Sensors (Basel) ; 16(8)2016 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-27556469

RESUMO

Three-dimensional information of the burden surface in high temperature and excessive dust industrial conditions has been previously hard to obtain. This paper presents a novel microstrip-fed dielectric-filled waveguide antenna element which is resistant to dust and high temperatures. A novel microstrip-to-dielectric-loaded waveguide transition was developed. A cylinder and cuboid composite structure was employed at the terminal of the antenna element, which improved the return loss performance and reduced the size. The proposed antenna element was easily integrated into a T-shape multiple-input multiple-output (MIMO) imaging radar system and tested in both the laboratory environment and real blast furnace environment. The measurement results show that the proposed antenna element works very well in industrial 3D imaging radar.

14.
J Environ Sci (China) ; 17(1): 76-80, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15900762

RESUMO

The nitrogen and fluorine co-doped TiO2 polycrystalline powder was synthesized by calcinations of the hydrolysis product of tetrabutyl titanate with ammonium fluoride. Nitrogen and fluorine co-doping causes the absorption edge of TiO2 to shift to a lower energy region. The photocatalytic activity of co-doped TiO2 with anatase phases was found to be 2.4 times higher than that of the commercial TiO2 photocatalyst Degussa P25 for phenol decomposition under visible light irradiation. The co-doped TiO2 powders only contain anatase phases even at 1000 degrees C. Apparently, ammonium fluoride added retarded phase transformation of the TiO2 powders from anatase to rutile. The substitutional fluorine and interstitial nitrogen atoms in co-doped TiO2 polycrystalline powder were responsible for the vis light response and caused the absorption edge of TiO2 to shift to a lower energy region.


Assuntos
Poluentes Ambientais , Luz , Compostos Orgânicos/química , Fotoquímica/métodos , Titânio/química , Absorção , Compostos de Amônio , Catálise , Fluoretos/química , Flúor/química , Nitrogênio/química , Compostos de Amônio Quaternário , Temperatura , Difração de Raios X
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