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1.
Opt Lett ; 48(24): 6392-6395, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099756

RESUMO

We propose and experimentally demonstrate a photonic time-delay reservoir computing (TDRC) system with random distributed optical feedback under optical injection. To evaluate the performance, we calculate the memory ability and perform two benchmark tasks, i.e., chaotic time series prediction and nonlinear channel equalization task. Our numerical results show that the proposed TDRC has a superior performance compared with the case with conventional single optical feedback. This is attributed to the fact that the random distributed optical feedback offers multiple external cavity modes, which enhance the nonlinearity of the reservoir laser. Additionally, the experimental result also shows that our proposed TDRC scheme outperforms the computer with single optical feedback in the chaotic time series prediction task. To the best of our knowledge, our work offers a novel path to improve the performance of TDRC by introducing random distributed optical feedback.

2.
Opt Express ; 30(13): 23909-23917, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36225062

RESUMO

We demonstrate the direct generation of visible vortex beams (LG01 mode) from a doughnut-shaped diode-pumped Pr:YLF laser. In continuous-wave mode, the maximum vortex output power was 36 mW at 523 nm, 354 mW at 607 nm, 838 mW at 639 nm, 722 mW at 721 nm, respectively. Moreover, based on this operation, the orange and red passively Q-switched vortex lasers were also achieved by inserting a Co:MgAl2O4 crystal into the laser cavity as a saturable absorber. The shortest pulse width of Q-switched vortex laser was 58 ns for 607 nm, and 34 ns for 639 nm, respectively. Our work provides a reliable and efficient method for the direct generation of visible vortex lasers for potential applications.

3.
Anal Chem ; 93(43): 14425-14431, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34672522

RESUMO

As the most important small molecules revealing the origins of life, amino acids (AAs) play essential roles in living organisms and their facile enantiodiscrimination has long been a great challenge for analytical chemists. Inspired by the specific stereomatching effect between biomolecules and AA enantiomers, herein, we first developed a bio-inspired highly sensitive platform based on an extended-gate metal-oxide-semiconductor field-effect-transistor (EG-MOSFET) for highly sensitive AA enantiodiscrimination. Bovine serum albumin (BSA) was self-assembled on deposited Au surfaces to afford the extended gate (EG) sensing unit, and its enantiorecognition ability was initially verified using common electrochemical techniques. The EG was thereafter installed to a MOSFET to build the desired BSA-EG-MOSFET highly sensitive chiral sensing platform, which realized the efficient enantiodiscrimination of essential AAs with high sensitivity, where effective chiral resolution was achieved at the femtomole level to phenylalanine (Phe). Combining molecular docking and circular dichroism spectroscopy, the weak intermolecular interactions between BSA and AAs enantiomers were investigated and the mechanism for signal amplification was proposed. Our results demonstrate that the as-fabricated biosensor has great potential in highly sensitive chiral sensing fields and can also afford a potential tool for biomolecular interaction investigations.


Assuntos
Aminoácidos , Técnicas Biossensoriais , Simulação de Acoplamento Molecular , Óxidos , Semicondutores
4.
Neural Netw ; 179: 106575, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39126992

RESUMO

Time-delay reservoir computing (TDRC) represents a simplified variant of recurrent neural networks, employing a nonlinear node with a feedback mechanism to construct virtual nodes. The capabilities of TDRC can be enhanced by transitioning to a deep architecture. In this work, we propose a novel photonic deep residual TDRC (DR-TDRC) with augmented capabilities. The additional time delay added to the residual structure enables DR-TDRC superior to traditional deep structures across various benchmark tasks, especially in memory capability and almost an order of magnitude improvement in nonlinear channel equalization. Additionally, a specifically designed clipping algorithm is utilized to counteract the damage of redundant layers in deep structures, enabling the extension of the deep TDRC to dozens rather than just a few layers, with higher performance. We experimentally demonstrate the proof-of-concept with a 4-layer DR-TDRC containing 960 interrelated neurons (240 neurons per layer), based on four injection-locked distributed feedback lasers. We confirm the potential for scalable deep RC with elevated performance. Our results provide a feasible approach for expanding deep photonic computing to satisfy the boosting demand for artificial intelligence.


Assuntos
Algoritmos , Redes Neurais de Computação , Aprendizado Profundo , Fatores de Tempo , Inteligência Artificial , Neurônios/fisiologia , Dinâmica não Linear , Retroalimentação , Fótons
5.
Tob Induc Dis ; 222024.
Artigo em Inglês | MEDLINE | ID: mdl-38250631

RESUMO

INTRODUCTION: This study explores the association of individual cognition and social environment of smoking with autonomy over tobacco, providing evidence and insights to help smokers effectively prevent and reduce tobacco dependence. METHODS: Data were collected from 1389 participants, aged ≥15 years, by face-to-face interviews from June 2018 to November 2019 in central China. We assessed autonomy over tobacco using the Autonomy Over Smoking Scale (AUTOS), including Withdrawal Symptoms (WS), Psychological Dependence (PD) and Cue-induced Cravings (CC), and examined factors of individual cognition and social environment, as well as covariates, including demographic characteristics, health status, and smoking behavior. RESULTS: AUTOS total score was 16.92 ± 9.05, WS score was the lowest (4.40 ± 3.36) in the three subscales, and CC score was the highest (6.88 ± 3.2). After adjustment, WS score of having a greater awareness of smoking hazards to one's own health was lower than those who had no awareness (ß=0.14; 95% CI: -0.31-0.00), and the total score of AUTOS, the score of PD and CC for those who thought smoking was 'more helpful (high)' to interpersonal communication were higher than 'not helpful (not at all)' (ß=0.14; 95% CI: 0.01-0.28 with ß=0.16; 95% CI: 0.02-0.29; and ß=0.14; 95% CI: 0.00-0.28; respectively). Having a greater difficulty in smoking cessation was associated with higher AUTOS total and subscale scores (p<0.001). Notably, none of the social-environmental factors included had a significant association with AUTOS scores. CONCLUSIONS: Interventions targeting individual cognitive factors of tobacco dependence seem to be more effective in smoking cessation. Future research may explore the influence of family and workplace among social environmental factors, which may reveal the effect of a binding force.

6.
PeerJ ; 11: e15925, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37641595

RESUMO

Quinoa (Chenopodium quinoa Willd.) is a highly nutritious food product with a comprehensive development prospect. Here, we discussed the effect of Bacillus amyloliquefaciens 11B91 on the growth, development and salt tolerance (salt concentrations: 0, 150, 300 mmol·L-1) of quinoa and highlighted a positive role for the application of plant growth-promoting rhizobacteria bacteria in quinoa. In this artical, the growth-promoting effect of Bacillus amyloliquefaciens 11B91 on quinoa (Longli No.1) and the changes in biomass, chlorophyll content, root activity and total phosphorus content under salt stress were measured. The results revealed that plants inoculated with 11B91 exhibited increased maximum shoot fresh weight (73.95%), root fresh weight (75.36%), root dry weight (136%), chlorophyll a (65.32%) contents and chlorophyll b (58.5%) contents, root activity (54.44%) and total phosphorus content (16.66%). Additionally, plants inoculated with 11B91 under salt stress plants showed significantly improved, fresh weight (107%), dry weight (133%), chlorophyll a (162%) contents and chlorophyll b (76.37%) contents, root activity (33.07%), and total phosphorus content (42.73%).


Assuntos
Bacillus amyloliquefaciens , Chenopodium quinoa , Clorofila A , Fósforo , Estresse Salino
7.
Mol Membr Biol ; 28(2): 90-102, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21231793

RESUMO

Since being introduced globally as Aspirin in 1899, acetylsalicylic acid (ASA) has been widely used as an analgesic, immune-regulatory, anti-pyretic and anti-thrombotic drug. ASA and its metabolite, salicylate, were also reported to be able to modulate antigen presenting functions of dendritic cells (DC). However, the intracellular targets of ASA in DC are still poorly understood. Since phagocytosis is the initial step taken by antigen-presenting cells in the uptake of antigens for processing and presentation, ASA might exerts its immune-regulatory effects by regulating phagocytosis. Here we show that ASA inhibits phagocytosis and modulates expression of endosomal SNAREs, such as Vti1a, Vti1b, VAMP-3, VAMP-8 and Syn-8 (but not syn-6 and syn-16) in DC. We further show that the phagocytic inhibitory effect of ASA is dependent on the expression of Vti1a and Vti1b. Consistently, Vti1a and Vti1b localize to the phagosomes and up-regulation of Vti1a and Vti1b inhibits phagocytosis in DC. Our results suggest that ASA modulates phagocytosis in part through the control of endosomal SNARE protein expression and localization in DC. All experiments were performed using either a murine DC line (DC2.4) or primary DC derived from murine bone marrow cells.


Assuntos
Aspirina/farmacologia , Células Dendríticas/imunologia , Fagocitose/efeitos dos fármacos , Proteínas Qb-SNARE/genética , Animais , Linhagem Celular , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Eletroporação , Citometria de Fluxo , Imunofluorescência , Camundongos , Camundongos Endogâmicos C57BL , Fagossomos/genética , Reação em Cadeia da Polimerase , Proteínas Qb-SNARE/metabolismo , Regulação para Cima/efeitos dos fármacos
8.
PLoS One ; 17(3): e0261710, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35271574

RESUMO

Apocynum venetum L. (Apocynaceae) is valuable for its medicinal compounds and fiber content. Native A. venetum populations are threatened and require protection. Wild A. venetum resources are limited relative to market demand and a poor understanding of the composition of A. venetum at the molecular level. The chloroplast genome contains genetic markers for phylogenetic analysis, genetic diversity evaluation, and molecular identification. In this study, the entire genome of the A. venetum chloroplast was sequenced and analyzed. The A. venetum cp genome is 150,878 bp, with a pair of inverted repeat regions (IRA and IRB). Each inverted repeat region is 25,810 bp, which consist of large (LSC, 81,951 bp) and small (SSC, 17,307 bp) single copy areas. The genome-wide GC content was 38.35%, LSC made up 36.49%, SSC made up 32.41%, and IR made up 43.3%. The A. venetum chloroplast genome encodes 131 genes, including 86 protein-coding genes, eight ribosomal RNA genes, and 37 transfer RNA genes. This study identified the unique characteristics of the A. venetum chloroplast genome, which will help formulate effective conservation and management strategies as well as molecular identification approaches for this important medicinal plant.


Assuntos
Apocynum , Genoma de Cloroplastos , Apocynum/genética , Composição de Bases , Cloroplastos/genética , Filogenia
9.
PeerJ ; 9: e10702, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33520465

RESUMO

BACKGROUND: Plant-growth-promoting rhizobacteria (PGPR) can promote plant growth and enhance plant tolerance to salt stress. Pseudomonas sp. strain M30-35 might confer abiotic stress tolerance to its host plants. We evaluated the effects of M30-35 inoculation on the growth and metabolite accumulation of Chenopodium quinoa Willd. during salt stress growth conditions. METHODS: The effects of M30-35 on the growth of C. quinoa seedlings were tested under salt stress. Seedling growth parameters measured included chlorophyll content, root activity, levels of plant- phosphorus (P), and saponin content. RESULTS: M30-35 increased biomass production and root activity compared to non-inoculated plants fertilized with rhizobia and plants grown under severe salt stress conditions. The photosynthetic pigment content of chlorophyll a and b were higher in M30-35-inoculated C. quinoa seedlings under high salt stress conditions compared to non-inoculated seedlings. The stability of P content was also maintained. The content of saponin, an important secondary metabolite in C. quinoa, was increased by the inoculation of M30-35 under 300 mM NaCl conditions. CONCLUSION: Inoculation of M30-35 rescues the growth diminution of C. quinoa seedlings under salt stress.

10.
Biochem Biophys Res Commun ; 387(2): 371-5, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19607812

RESUMO

During an inflammation and upon encountering pathogens, immature dendritic cells (DC) undergo a maturation process to become highly efficient in presenting antigens. This transition from immature to mature state is accompanied by various physiological, functional and morphological changes including reduction of caspase activity and inhibition of phagocytosis in the mature DC. Caspases are cysteine proteases which play essential roles in apoptosis, necrosis and inflammation. Here, we demonstrate that VAMP-8, (a SNARE protein of the early/late endosomes) which has been shown previously to inhibit phagocytosis in DC, is a substrate of caspases. Furthermore, we identified two putative conserved caspase recognition/cleavage sites on the VAMP-8 protein. Consistent with the up-regulation of VAMP-8 expression upon treatment with caspase inhibitor (CI), immature DC treated with CI exhibits lower phagocytosis activity. Thus, our results highlight the role of caspases in regulating VAMP-8 expression and subsequently phagocytosis during maturation of DC.


Assuntos
Caspases/metabolismo , Células Dendríticas/imunologia , Fagocitose , Proteínas R-SNARE/metabolismo , Sequência de Aminoácidos , Animais , Inibidores de Caspase , Linhagem Celular , Lipopolissacarídeos/imunologia , Camundongos , Dados de Sequência Molecular , Proteínas R-SNARE/biossíntese , Regulação para Cima
11.
Mol Biol Cell ; 16(8): 3705-18, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15930121

RESUMO

Mice deficient for p66shcA represent an animal model to link oxidative stress and aging. p66shcA is implicated in oxidative stress response and mitogenic signaling. Phosphorylation of p66shcA on Ser36 is critical for its function in oxidative stress response. Here we report the identification of ERK as the kinase phosphorylating p66shcA on Ser36. Activation of ERKs was necessary and sufficient for Ser36 phosphorylation. p66shcA interacted with ERK and was demonstrated to be a substrate for ERK, with Ser36 being the major phosphorylation site. Furthermore, in response to H2O2, inhibition of ERK activation repressed p66shcA-dependent phosphorylation of FOXO3a and the down-regulation of its target gene p27kip1. Down-regulation of p27 might promote cell survival, as p27 played a proapoptotic role in oxidative stress response. As a feedback regulation, Ser36 phosphorylated p66shcA attenuated H2O2-induced ERK activation, whereas p52/46shcA facilitated ERK activation, which required tyrosine phosphorylation of CH1 domain. p66shcA formed a complex with p52/46ShcA, which may provide a platform for efficient signal propagation. Taken together, the data suggest there exists an interplay between ERK and ShcA proteins, which modulates the expression of p27 and cell response to oxidative stress.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Estresse Oxidativo , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Proteína Forkhead Box O3 , Regulação da Expressão Gênica , Peróxido de Hidrogênio/farmacologia , Camundongos , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica , Serina/genética , Serina/metabolismo , Proteínas Adaptadoras da Sinalização Shc , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
12.
J Immunol ; 180(5): 3148-57, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18292538

RESUMO

Phagocytosis is a specialized mechanism used by mammalian cells, particularly the cells of the immune system, such as dendritic cells (DC) and macrophages, to protect the host against infection. The process involves a complex cascade of pathways, from the ligation of surface receptors of phagocytes with components of the microorganism's surface, formation of phagosomes and subsequently phagolysosomes, to the eventual presentation of foreign Ags. Vesicle-associated membrane protein (VAMP)-8/endobrevin has been shown previously to function in the endocytic pathways. Our results showed that VAMP-8 colocalized with lysosome-associated membrane protein-2, and a significant amount of VAMP-8 was recruited to the phagosomes during bacterial ingestion. However, overexpression of VAMP-8 significantly inhibited phagocytosis in DC. We also found that the phagocytic activity of VAMP-8-/- DC was significantly higher than wild-type VAMP-8+/+ DC, thus further confirming that VAMP-8 negatively regulates phagocytosis in immature DC.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Regulação para Baixo/imunologia , Escherichia coli/imunologia , Fagocitose/imunologia , Proteínas R-SNARE/fisiologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células Dendríticas/microbiologia , Regulação para Baixo/genética , Endossomos/imunologia , Endossomos/metabolismo , Endossomos/microbiologia , Escherichia coli/metabolismo , Proteínas de Fluorescência Verde/imunologia , Proteínas de Fluorescência Verde/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fagocitose/genética , Proteínas R-SNARE/deficiência , Proteínas R-SNARE/genética
13.
J Biol Chem ; 283(3): 1713-1722, 2008 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-18003616

RESUMO

Dendritic cells (DC) are professional antigen-presenting cells that possess specific and efficient mechanisms to initiate immune responses. Upon encounter with pathogens, immature DC will go through a maturation process that converts them to highly immunogenic mature DC. Despite the fact that nitric oxide (NO) was produced in large amounts in maturing DC, it is still unclear whether NO is the key molecule that initiates and enhances DC maturation and T cell proliferation, respectively. Here, we report that NO donor and overexpression of either nitric-oxide synthase 2 (NOS2) or nitric-oxide synthase 3 (NOS3) alone can induce surface expression of major histocompatibility complex class II (MHC II) and both the essential co-stimulatory molecules CD80 and CD86 in immature DC. Consistently, NO donor-treated immature DC were capable of enhancing T cell proliferation in vitro in the absence of lipolysaccharide. Interestingly, NOS2 interacts with CD74 (the MHC II-associated invariant chain), and the degradation of CD74 by caspases in immature DC was inhibited upon treatment with NO donor. Because the trafficking of MHC II is CD74-dependent, the increase in cell surface localization of MHC II in maturing DC is in part due to the increase in CD74 protein expression in the presence of NOS2 and NO.


Assuntos
Antígenos de Diferenciação de Linfócitos B/metabolismo , Caspase 1/metabolismo , Caspases/metabolismo , Células Dendríticas/citologia , Células Dendríticas/enzimologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Sequência de Aminoácidos , Animais , Apresentação de Antígeno/efeitos dos fármacos , Antígenos de Diferenciação de Linfócitos B/química , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Caspases Iniciadoras , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe II/química , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Dados de Sequência Molecular , Doadores de Óxido Nítrico/farmacologia , Ligação Proteica/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/enzimologia , Linfócitos T/imunologia
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