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1.
Bioessays ; 46(9): e2400091, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38962845

RESUMO

The cGAS-STING signaling pathway plays a pivotal role in sensing cytosolic DNA and initiating innate immune responses against various threats, with disruptions in this pathway being associated with numerous immune-related disorders. Therefore, precise regulation of the cGAS-STING signaling is crucial to ensure appropriate immune responses. Recent research, including ours, underscores the importance of protein condensation in driving the activation and maintenance of innate immune signaling within the cGAS-STING pathway. Consequently, targeting condensation processes in this pathway presents a promising approach for modulating the cGAS-STING signaling and potentially managing associated disorders. In this review, we provide an overview of recent studies elucidating the role and regulatory mechanism of protein condensation in the cGAS-STING signaling pathway while emphasizing its pathological implications. Additionally, we explore the potential of understanding and manipulating condensation dynamics to develop novel strategies for mitigating cGAS-STING-related disorders in the future.


Assuntos
Imunidade Inata , Proteínas de Membrana , Nucleotidiltransferases , Transdução de Sinais , Humanos , Nucleotidiltransferases/metabolismo , Proteínas de Membrana/metabolismo , Animais , DNA/metabolismo
2.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37955665

RESUMO

Brachial plexus avulsion injury (BPAI) is a severe peripheral nerve injury that leads to functional reorganization of the brain. However, the interhemispheric coordination following contralateral cervical 7 nerve transfer remains unclear. In this study, 69 BPAI patients underwent resting-state functional magnetic resonance imaging examination to assess the voxel-mirrored homotopic connectivity (VMHC), which reveals the interhemispheric functional connection. The motor function of the affected upper extremity was measured using the Fugl-Meyer Assessment of Upper Extremity (FMA-UE) scale. The VMHC analysis showed significant differences between the bilateral precentral gyrus, supplementary motor area (SMA), middle frontal gyrus (MFG), and insula. Compared to the preoperative group, the VMHC of the precentral gyrus significantly increased in the postoperative short-term group (PO-ST group) but decreased in the postoperative long-term group (PO-LT group). Additionally, the VMHC of the SMA significantly increased in the PO-LT group. Furthermore, the VMHC of the precentral gyrus in the PO-ST group and the SMA in the PO-LT group were positively correlated with the FMA-UE scores. These findings highlight a positive relationship between motor recovery and increased functional connectivity of precentral gyrus and SMA, which provide possible therapeutic targets for future neuromodulation interventions to improve rehabilitation outcomes for BPAI patients.


Assuntos
Plexo Braquial , Transferência de Nervo , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo , Mapeamento Encefálico/métodos , Plexo Braquial/diagnóstico por imagem , Plexo Braquial/cirurgia
3.
Anal Chem ; 96(11): 4623-4631, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38456770

RESUMO

Developing new electrochemiluminescence (ECL) luminators with high stability, wide applicability, and strong designability is of great strategic significance to promote the ECL field to the frontier. Here, driven by the I···N bond, 1,3,5-trifluoro-2,4,6-triiodobenzene (TFTI) and 2,4,6-trimethyl-1,3,5-triazine (TMT) self-assembled into a novel halogen cocrystal (TFTI-TMT) through slow solution volatilization. Significant difference of charge density existed between the N atoms on TMT and the σ-hole of the I atoms on TFTI. Upon the induction of σ-hole effect, high-speed and spontaneous charge transferring from TMT to the σ-hole of TFTI occurred, stimulating exciting ECL signals. Besides, the σ-hole of the I atoms could capture iodine ions specifically, which blocked the original charge transfer from the N atoms to the σ-hole, causing the ECL signal of TFTI-TMT to undergo a quenching rate as high as 92.9%. Excitingly, the ECL sensing of TFTI-TMT toward I- possessed a wide linear range (10-5000 nM) and ultralow detection limit (3 nM) in a real water sample. The halogen cocrystal strategy makes σ-hole a remarkable new viewpoint of ECL luminator design and enables ECL analysis technology to contribute to addressing the environmental and health threats posed by iodide pollution.

4.
Small ; : e2405568, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39308439

RESUMO

Rechargeable magnesium batteries (RMBs) face with the challenge of interphase passivation between electrolytes and Mg anodes. Compared with ether electrolytes, carbonate solvents possess the superior electrochemical stability at cathode side, but their incompatibility with Mg metal, high viscosity, and desolvation energy barrier restrict their practical utilization in RMBs. Herein, the "unwanted-impurity" water with high concentration is revisited and employed as multifunctional additive in carbonate electrolyte to improve the reversibility of RMBs. Water additive enables the localized deep eutectic effect, reduces the viscosity of carbonate electrolyte, and improves the Mg ion conductivity. The water molecules also participate the solvation sheath of Mg ions, resulting in the reduction of Mg deposition overpotential and inhibition of parasitic reaction. Furthermore, the co-intercalated water molecules in V2O5 cathode layers enable the stabilization of intercalation structure and supply of additional magnesiophilic sites. Cooperated with the binder-decorated Mg powder anode, the propylene carbonate electrolyte with water additive endows Mg||Mg symmetric cells and Mg||V2O5 full cells with satisfactory cycling performance and high-voltage stability. This work revisits the impact of impurity water and provides a practical strategy for the utilization of conventional low-cost carbonate electrolyte family, broadening the design and formulation of electrolytes for chlorine-free and high-voltage RMBs.

5.
New Phytol ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39140987

RESUMO

During Arabidopsis embryogenesis, the transition of the embryo's symmetry from radial to bilateral between the globular and heart stage is a crucial event, involving the formation of cotyledon primordia and concurrently the establishment of a shoot apical meristem (SAM). However, a coherent framework of how this transition is achieved remains to be elucidated. In this study, we investigated the function of DELAYED GREENING 1 (DG1) in Arabidopsis embryogenesis using a newly identified dg1-3 mutant. The absence of chloroplast-localized DG1 in the mutants led to embryos being arrested at the globular or heart stage, accompanied by an expansion of WUSCHEL (WUS) and SHOOT MERISTEMLESS (STM) expression. This finding pinpoints the essential role of DG1 in regulating the transition to bilateral symmetry. Furthermore, we showed that this regulation of DG1 may not depend on its role in plastid RNA editing. Nevertheless, we demonstrated that the DG1 function in establishing bilateral symmetry is genetically mediated by GENOMES UNCOUPLED 1 (GUN1), which represses the transition process in dg1-3 embryos. Collectively, our results reveal that DG1 functionally antagonizes GUN1 to promote the transition of the Arabidopsis embryo's symmetry from radial to bilateral and highlight the role of plastid signals in regulating pattern formation during plant embryogenesis.

6.
Opt Express ; 32(5): 7254-7275, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439411

RESUMO

Elastic optical network (EON) is a critical transmission infrastructure for emerging new applications due to its spectral efficiency and flexibility. Nowadays, numerous confidential lightpaths (CLPs) are carried over EON to support security-sensitive users. However, they are vulnerable to crosstalk attacks at the optical layer, typically aimed at eavesdropping on the carried data or even disrupting connections. Due to the transparent nature of the optical signals, such attacks are difficult to detect and could last for a long time, resulting in data leakage even spreading throughout the network. This paper presents a novel routing and spectrum allocation (RSA) algorithm to protect CLPs from crosstalk attacks. We investigate intra-channel and inter-channel crosstalk attacks and develop a metric to quantify crosstalk leakage risks (CLRs). We first formulate an ILP model to plan CLPs with a minimum CLR. To solve the same problem for large-scale networks, we also propose a heuristic algorithm, i.e., crosstalk-attack-aware RSA. Results indicate that the proposed algorithm is capable of reducing CLR by 23%.

7.
Bioorg Med Chem ; 111: 117869, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39126834

RESUMO

Recently, the sortilin receptor (SORT1) was found to be preferentially over-expressed on the surface of many cancer cells, which makes SORT1 a novel anticancer target. The SORT1 binding proprietary peptide TH19P01 could achieve the SORT1-mediated cancer cell binding and subsequent internalization. Inspired by the peptide-drug conjugate (PDC) strategy, the TH19P01-camptothecin (CPT) conjugates were designed, efficiently synthesized, and evaluated for their anticancer potential in this study. The water solubility, in vitro anticancer activity, time-kill kinetics, cellular uptake, anti-migration activity, and hemolysis effects were systematically estimated. Besides, in order to monitor the release of CPT from conjugates in real-time, the CPT/Dnp-based "turn on" hybrid peptide was designed, which indicted that CPT could be sustainably released from the hybrid peptide in both human serum and cancer cellular environments. Strikingly, compared with free CPT, the water solubility, cellular uptake, and selectivity towards cancer cells of hybrid peptide LYJ-2 have all been significantly enhanced. Moreover, unlike free CPT or TH19P01, LYJ-2 exhibited selective anti-proliferative and anti-migration effects against SORT1-positive MDA-MB-231 cells. Collectively, this study not only established efficient strategies to improve the solubility and anticancer potential of chemotherapeutic agent CPT, but also provided important references for the future development of TH19P01 based PDCs targeting SORT1.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Antineoplásicos , Camptotecina , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camptotecina/farmacologia , Camptotecina/química , Camptotecina/síntese química , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/síntese química , Relação Estrutura-Atividade , Estrutura Molecular , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Movimento Celular/efeitos dos fármacos
8.
AIDS Res Ther ; 21(1): 46, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39061023

RESUMO

BACKGROUND: Males have accounted for a significant share of new HIV infections among young people in the recent years. This study aimed to identify the factors associated with risky sexual behaviors, including early sexual debut, multiple sexual partnership and condomless sex, among sexually active male college students and provide implications for tailored health interventions. METHODS: The cross-sectional study was conducted from December 2020 to December 2021 in 16 colleges that were located in Sichuan Province, one of the high-risk areas in China. Overall 1640 male college students who reported sexually experienced were analyzed in this study. Multivariable logistic regression analysis was applied to determine factors associated with early sexual debut, multiple sexual partnership and condomless sex. RESULTS: The average age of included male students was 19.95 ± 1.56. Of them, 27.74% initiated sexual behavior early, 48.60% reported multiple sexual partnership, and 16.52% did not use condoms at the latest sexual intercourse. Students who were younger (age ≤ 19, AOR = 7.60, 95%CI: 4.84-11.93; age20-21, AOR = 3.26, 95%CI: 2.04-5.21) and self-identified as sexual minorities (AOR = 2.38, 95%CI: 1.69-3.36) were more likely to have early sexual debut. The odds of having multiple sexual partners were higher among those who were ethnic minorities (AOR = 1.79, 95%CI: 1.33-2.41) and accepted extramarital sex (AOR = 1.33, 95%CI: 1.03-1.71). The likelihood of engaging in condomless sex at the latest sexual intercourse was lower among those who had sufficient knowledgeable about HIV (AOR = 0.63, 95%CI: 0.44-0.89), were very confident in condom use efficacy (AOR = 0.26, 95%CI: 0.16-0.43) and confident (AOR = 0.48, 95%CI: 0.34-0.69). Early sexual debut was positively associated with multiple sexual partnership (AOR = 3.64, 95%CI: 2.82-4.71) and condomless sex at the latest intercourse (AOR = 1.53, 95%CI: 1.07-2.20), respectively. CONCLUSION: Early sexual debut, multiple sexual partnership and condomless sex were of considerable concern among male college students. Comprehensive sex education curricula were advised by developing customized information on HIV prevention, sexuality and empowering students with assertiveness and negotiation skills with regard to condom use during and before college.


Assuntos
Preservativos , Infecções por HIV , Assunção de Riscos , Comportamento Sexual , Estudantes , Sexo sem Proteção , Humanos , Masculino , Estudos Transversais , China/epidemiologia , Estudantes/estatística & dados numéricos , Estudantes/psicologia , Adulto Jovem , Adolescente , Comportamento Sexual/estatística & dados numéricos , Universidades , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Preservativos/estatística & dados numéricos , Sexo sem Proteção/estatística & dados numéricos , Parceiros Sexuais , Inquéritos e Questionários , Adulto
9.
J Clin Nurs ; 33(5): 1976-1994, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38450810

RESUMO

AIM: To identify and appraise the quality of evidence of transitional care interventions on quality of life in lung cancer patients. BACKGROUND: Quality of life is a strong predictor of survival. The transition from hospital to home is a high-risk period for patients' readmission and death, which seriously affect their quality of life. DESIGN: Systematic review and meta-analysis. METHODS: The PubMed, Embase, Cochrane Library, Web of Science and CINAHL databases were searched from inception to 22 October 2022. The primary outcome was quality of life. Statistical analysis was conducted using Review Manager 5.4, results were expressed as standard mean difference (SMD) with a 95% confidence interval (CI). The risk of bias of the included studies was assessed using the Cochrane risk of bias assessment tool. This study was complied with PRISMA guidelines and previously registered in PROSPERO (CRD42023429464). RESULTS: Fourteen randomized controlled trials were included consisting of a total of 1700 participants, and 12 studies were included in the meta-analysis. It was found that transitional care interventions significantly improved quality of life (SMD = 0.21, 95% CI: 0.02 to 0.40, p = .03) and helped reduce symptoms (SMD = -0.65, 95% CI: -1.13 to -0.18, p = .007) in lung cancer patients, but did not significantly reduce anxiety and depression, and the effect on self-efficacy was unclear. CONCLUSIONS: This study shows that transitional care interventions can improve quality of life and reduce symptoms in patients, and that primarily educational interventions based on symptom management theory appeared to be more effective. But, there was no statistically significant effect on anxiety and depression. RELEVANCE TO CLINICAL PRACTICE: This study provides references for the application of transitional care interventions in the field of lung cancer care, and encourages nurses and physicians to apply transitional care plans to facilitate patients' safe transition from hospital to home. PATIENT OR PUBLIC CONTRIBUTION: No Patient or Public Contribution.


Assuntos
Neoplasias Pulmonares , Qualidade de Vida , Cuidado Transicional , Humanos , Neoplasias Pulmonares/psicologia , Neoplasias Pulmonares/enfermagem , Neoplasias Pulmonares/terapia , Qualidade de Vida/psicologia , Cuidado Transicional/normas
10.
Int J Mol Sci ; 25(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38256133

RESUMO

Paeonia ostii 'Feng Dan' is widely cultivated in China for its ornamental, medicinal, and edible properties. The whole plant of tree peony is rich in bioactive substances, while the comprehensive understanding of metabolites in the leaves is limited. In this study, an untargeted metabolomics strategy based on UPLC-ESI-TOF-MS was conducted to analyze the dynamic variations of bioactive metabolites in P. ostii 'Feng Dan' leaves during development. A total of 321 metabolites were rapidly annotated based on the GNPS platform, in-house database, and publications. To accurately quantify the selected metabolites, a targeted method of HPLC-ESI-QQQ-MS was used. Albiflorin, paeoniflorin, pentagalloylglucose, luteolin 7-glucoside, and benzoylpaeoniflorin were recognized as the dominant bioactive compounds with significant content variations during leaf development. Metabolite variations during the development of P. ostii 'Feng Dan' leaves are greatly attributed to the variations in antioxidant activities. Among all tested bacteria, the leaf extract exhibited exceptional inhibitory effects against Streptococcus hemolytis-ß. This research firstly provides new insights into tree peony leaves during development. The stages of S1-S2 may be the most promising harvesting time for potential use in food or pharmaceutical purposes.


Assuntos
Paeonia , China , Bases de Dados Factuais , Alimentos , Espectrometria de Massa com Cromatografia Líquida
11.
J Environ Manage ; 370: 122555, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39299130

RESUMO

Humic acids (HAs) would be excessively released during thermal hydrolysis pretreatment (THP) and deeply disturb anaerobic digestion (AD) of waste activated sludge (WAS). The molecular weights of HAs could affect HAs entering microbial cells, binding with digestive enzymes and participating in electron transfer, thereby determining its influences on sludge AD. Results in this study confirmed the different influences of HAs from diverse sources on sludge AD indeed had significant correlations with their molecular weights. The presence of commercial HAs (SAHA) inhibited methane production by 53.3% at 0.5 g/L while HAs extracted from raw sludge (WNHA) increased methane production by 20.5% at the same concentration, which attribute to the comprehensive impacts from their differences in functional group compositions and molecular weights. Moreover, comparing to WNHA, the HAs extracted from thermally hydrolyzed sludge (THHA) showed unchanged functional group compositions but reduced methane generation facilitation to 5.1%, which only be due to its decreased molecular weights. In-depth research indicated that HAs influences on enzymes were closely relative to its molecular weight. HAs with greater molecular weights presented more significant inhibition to extracellular enzymes while micromolecular HAs affected intracellular enzymes more. Furthermore, macromolecular HAs promoted sludge solubilization and acidification but hindered hydrolysis and methanogenesis, whereas micromolecular HAs promoted acidification but inhibited methanogenesis. This study underscored the importance of changes in molecular weight of HAs during sludge THP, offering insights into previous discrepancies in reports on HAs effects on sludge AD.

12.
Anal Chem ; 95(22): 8696-8705, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37224420

RESUMO

The application of covalent organic frameworks (COFs) in electrochemiluminescence (ECL) is promising in environmental monitoring. Developing an emerging design strategy to expand the class of COF-based ECL luminophores is highly desirable. Here, a COF-based host-guest system was constructed through guest molecular assembly to deal with nuclear contamination analysis. The efficient charge transport network was formed by inserting an electron-withdrawing guest tetracyanoquinodimethane (TCNQ) into the open space of the COF host (TP-TBDA; TP = 2,4,6-trihydroxy-1,3,5-benzenetricarbaldehyde and TBDA = 2,5-di(thiophen-2-yl)benzene-1,4-diamine) with an electron-donating property; the construction of the COF-based host-guest system (TP-TBDA@TCNQ) triggered the ECL emission of non-emitting TP-TBDA. Furthermore, the dense active sites in TP-TBDA were utilized to capture the target substance UO22+. The presence of UO22+ broke the charge-transfer effect in TP-TBDA@TCNQ, resulting in the weakening of the ECL signal, thus the established ECL system integrating the low detection limit with high selectivity monitors UO22+. This COF-based host-guest system provides a novel material platform for constructing late-model ECL luminophores and creates an opportunity for the vigorous ECL technology.

13.
Small ; 19(39): e2302254, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37236205

RESUMO

Covalent organic frameworks (COFs) show potentials in prominent photoelectric responses by judicious structural design. However, from the selections of monomers and condensation reactions to the synthesis procedures, the acquisition of photoelectric COFs has to meet overmuch high conditions, limiting the breakthrough and modulation in photoelectric responses. Herein, the study reports a creative "lock-key model" based on molecular insertion strategy. A COF with suitable cavity size, TP-TBDA, is used as the host to load guests. Merely through the volatilization of mixed solution, TP-TBDA and guests can be spontaneously assembled via non-covalent interactions (NCIs) to produce molecular-inserted COFs (MI-COFs). The NCIs between TP-TBDA and guests acted as a bridge to facilitate charge transfer in MI-COFs, unlocking the photoelectric responses of TP-TBDA. By exploiting the controllability of NCIs, the MI-COFs can realize the smart modulation of photoelectric responses by simply changing the guest molecule, thus avoiding the arduous selection of monomers and condensation reactions required by conventional COFs. The construction of molecular-inserted COFs circumvents complicated procedures for achieving performance improvement and modulation, providing a promising direction to construct late-model photoelectric responsive materials.

14.
Small ; 19(25): e2300571, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36919633

RESUMO

High-energy-density Li metal batteries (LMBs) with Nickel (Ni)-rich cathode and Li-metal anode have attracted extensive attention in recent years. However, commercial carbonate electrolytes bring severe challenges including poor cycling stability, severe Li dendrite growth and cathode cracks, and narrow operating temperature window, especially hardly work at below -40 °C. In this work, a 2.4 m lithium difluoro(oxalato)borate (LiDFOB) in ethyl acetate (EA) solvent with 20 wt% fluorocarbonate (FEC) (named 2.4m-DEF) is designed to solve Li+ transport dynamic at low temperature and improve interfacial stability between electrolyte with Li anode or Ni-rich cathode. Beneficial lower freezing point, lower viscosity, and higher dielectric constant of EA solvent, the electrolyte exhibits excellent Li+ transport dynamic. Relying on the unique Li+ solvation structure, more DFOB- anions and FEC solvents are decomposed to establish a stable solid electrolyte interface at electrolyte/electrode. Therefore, LiNi0.9 Co0.05 Mn0.05 O2 (NCM90)/Li LMB with 2.4m-DEF enables excellent rate capability (184 mA h g-1 at 30 C) and stable cycling performance with ≈93.7% of capacity retention after 200 cycles at 20 C and room temperature. Moreover, the NCM90/Li LMB with 2.4m-DEF exhibits surprising ultra-low-temperature performance, showing 173 mA h g-1 at -40 °C and 152 mA h g-1 at -60 °C, respectively.

15.
Opt Express ; 31(21): 34827-34842, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37859230

RESUMO

In conventional optical transport networks, the service form is the fixed bandwidth connectivity, which is not flexible for carrying bursting traffic. To support the time-varying traffic in an efficient way, researchers are studying the optical service units for building the more flexible optical transport network (OTN) connectivity, which is capable of dynamic hitless bandwidth adjustment. To better utilize the benefits of flexible connectivity, network operators need efficient algorithms to adjust the flexible connectivity bandwidth, especially in the network with a massive number of connections. In this paper, based on max-min fair bandwidth allocation criteria, we propose two traffic-based adaptive bandwidth adjustment algorithms to make bandwidth adjustment decisions, with the aim to improve bandwidth effectiveness. Simulation results show that the proposed algorithms can improve bandwidth utilization by up to 16%. Additionally, under high load conditions, it can reduce the loss in traffic bitrate by a maximum of 10%.

16.
Opt Express ; 31(12): 19006-19020, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381327

RESUMO

Quantum noise stream cipher based on quadrature-amplitude-modulation (QAM/QNSC) is a kind of physical layer encryption technology. However, the additional encryption penalty will significantly affect the practical deployment of QNSC, especially in the high capacity and long-haul transmission system. With our research, the encryption process of QAM/QNSC degrades the transmission performance of plaintext information. In this paper, we quantitatively analyze the encryption penalty of QAM/QNSC based on the proposed concept of effective minimum Euclidean distance. We calculate the theoretical signal-to-noise ratio sensitivity and encryption penalty of QAM/QNSC signals. A modified feedforward pilot-aided two-stage carrier phase recovery scheme is used to reduce the effect of laser phase noise and the encryption penalty. Experimental results achieve single-channel 205.9 Gbit/s 640km transmission with single carrier polarization-diversity-multiplexing 16-QAM/QNSC signal.

17.
Opt Express ; 31(14): 23229-23244, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37475413

RESUMO

Deterioration of the signal-to-noise ratio (SNR) is an important challenge in ultra-long multi optical line system (OLS) optical transmission systems. The non-uniform gain and cascading of the Erbium-doped fiber amplifier (EDFA) lead to SNR deterioration in transmission systems. In this paper, we propose two channel power equalization methods based on joint optimization of EDFA and Reconfigurable optical add-drop multiplexer (ROADM) configurations: 1) reinforcement learning (RL)-based channel power equalization (RL-PE) and 2) covariance matrix adaptive evolution strategy (CMA-ES) channel power equalization (CMA-PE). The simulation results indicate that the power equalization effect was improved by 1.9 dB through the CMA-PE method, while the RL-PE method led to a 1.5 dB improvement in an ultra-long 80-channel 7-OLS transmission system.

18.
Opt Lett ; 48(12): 3183-3186, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37319057

RESUMO

In this Letter, we present a scheme for detecting fiber-bending eavesdropping based on feature extraction and machine learning (ML). First, 5-dimensional features from the time-domain signal are extracted from the optical signal, and then a long short-term memory (LSTM) network is applied for eavesdropping and normal event classification. Experimental data are collected from a 60 km single-mode fiber transmission link with eavesdropping implemented by a clip-on coupler. Results show that the proposed scheme achieves a 95.83% detection accuracy. Furthermore, since the scheme focuses on the time-domain waveform of the received optical signal, additional devices and a special link design are not required.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação
19.
Opt Lett ; 48(24): 6500-6503, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099783

RESUMO

We propose and experimentally demonstrate a secure quantum noise stream cipher transmission system that integrates key generation and distribution. At the stage of carrier phase recovery, the estimated phase noise is used to generate randomness keys without additional equipment. Based on direct sequence spread spectrum technology, we integrate the distributed keys with quantum noise stream cipher signals. The key distribution and encryption transmission can be completed simultaneously without occupying additional bandwidth or time slots. By changing the position of distributed keys in the encryption base, the BER performance of QAM/QNSC signals cannot be affected by the keys. Experimental results demonstrate that the 54.5 Mbps key distribution and 31 Gbps encryption transmission without OSNR penalty can be achieved simultaneously over a 120 km standard single-mode fiber.

20.
J Magn Reson Imaging ; 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37994206

RESUMO

BACKGROUND: The uterus undergoes dynamic changes throughout the menstrual cycle. Diffusion kurtosis imaging (DKI) is based on the non-Gaussian distribution of water molecules and can perhaps represent the changes of uterine microstructure. PURPOSE: To investigate the temporal changes in DKI-parameters of the normal uterine corpus and cervix during the menstrual cycle. STUDY TYPE: Prospective. POPULATION: 21 healthy female volunteers (26.64 ± 4.72 years) with regular menstrual cycles (28 ± 7 days). FIELD STRENGTH/SEQUENCE: Readout segmentation of long variable echo-trains (RESOLVE)-based DKI and fast spin-echo T2-weighted sequences at 3.0T. ASSESSMENT: Each volunteer was scanned during the menstrual phase, ovulatory phase, and luteal phase. Regions of interest (ROI) were manually delineated in the endometrium, junctional zone, and myometrium of the uterine body, and in the mucosal layer, fibrous stroma layer, and loose stroma layer of the cervix. The mean Kapp (diffusion kurtosis coefficient), Dapp (diffusion coefficient), and ADC (apparent diffusion coefficient) values were measured in the ROI. STATISTICAL TESTS: ANOVA with Bonferroni or Tamhane correction. Intraclass correlation coefficient (ICC) for assessing agreement. P < 0.05 was considered statistically significant. RESULTS: During the menstrual cycle, the highest Kapp (0.848 ± 0.184) and lowest Dapp (1.263 ± 0.283 *10-3 mm2 /sec) values were found in the endometrium during the menstrual phase. The Dapp values for the myometrium were significantly higher than those of the endometrium and the junctional zone in every phase. Meanwhile, the Dapp values for the three zonal structures of the cervix during ovulation were significantly higher than those during the luteal phase. However, there was no significant difference in the ADC values of the loose stroma between ovulation and the luteal phase (P = 0.568). The reproducibility of DKI parameters was good (ICC, 0.857-0.944). DATA CONCLUSION: DKI can show dynamic changes of the normal uterus during the menstrual cycle. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

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