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1.
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%.

2.
J Acoust Soc Am ; 154(5): 3173-3187, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37971214

RESUMO

The received reverberation signal can be beamformed by utilizing a vertical array, generating a vertical-angle time record (VATR) that enables analysis of spatiotemporal distribution characteristics. Due to the influence of multipath propagation effects, deep-sea reverberation exhibits highly complex characteristics, especially in a seabed with significant depth variation. In a recent bistatic reverberation experiment with a vertical array receiver, peculiar bright stripes were observed in the VATR. These stripes are the result of scattering caused by large-scale bottom structures and are closely associated with seamounts. To accurately model and interpret these stripes, a bistatic reverberation model is initially established to reproduce the VATR. This model enables us to numerically simulate the spatiotemporal distribution of reverberation in the VATR, offering a qualitative explanation for these stripes. However, the model alone is incapable of predicting the specific stripe structure associated with a particular seamount. To address this limitation, an equation system is introduced to calculate the stripe parameters based on the seamount parameters. By analyzing and deducing the dependency of the stripes on the seamount, conclusions were drawn using the equation system. Ultimately, the presented model and equation system successfully reproduce and comprehensively explain the observed abnormal stripes from the experiment.

3.
Sensors (Basel) ; 23(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37571486

RESUMO

This paper presents a novel routing planning method based on multi-objective optimization to tackle the routing problem in computing power networks. The proposed method aims to improve the performance and efficiency of routing by considering multiple objectives. In this study, we first model the computing power network and formulate the routing problem as a multi-objective optimization problem. To address this problem, we introduce a non-dominated sorting genetic algorithm incorporating a ratio parameter adjustment strategy based on reinforcement learning. Extensive simulations are conducted to evaluate the performance of the proposed routing algorithm. The results demonstrate significant client latency and cost reductions, highlighting the algorithm's effectiveness. By providing a comprehensive solution to the routing problem in computing power networks, this work contributes to the field by offering improved performance and efficiency. The proposed method's ability to optimize multiple objectives sets it apart from existing approaches, making it a valuable contribution to the research community.

4.
Environ Sci Technol ; 57(21): 7978-7988, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37162498

RESUMO

The inhalation exposure of pesticide applicators and residents who live close to pesticide-treated fields is a worldwide concern in public health. Quantitative assessment of exposure to pesticide inhalation health risk highlights the need to accurately assess the bioaccessibility rather than the total content in ambient air. Herein, we developed an in vitro method to estimate the inhalation bioaccessibility of emamectin benzoate and validated its applicability using a rat plasma pharmacokinetic bioassay. Emamectin benzoate was extracted using the Gamble solution, with an optimized solid-to-liquid ratio (1/250), extraction time (24 h), and agitation (200 rpm), which obtained in vitro inhalation bioaccessibility consistent with its inhalation bioavailability in vivo (32.33%). The margin of exposure (MOE) was used to assess inhalation exposure risk. The inhalation unit exposures to emamectin benzoate of applicators and residents were 11.05-28.04 and 0.02-0.04 ng/m3, respectively, varying markedly according to the methods of application, e.g., formulations and nozzles. The inhalation risk assessment using present application methods appeared to be acceptable; however, the MOE of emamectin benzoate might be overestimated by 32% without considering inhalation bioaccessibility. Collectively, our findings contribute insights into the assessment of pesticide inhalation exposure based on bioaccessibility and provide guidance for the safe application of pesticides.


Assuntos
Resíduos de Praguicidas , Praguicidas , Animais , Ratos , Exposição por Inalação , Ivermectina/análise , Resíduos de Praguicidas/análise
5.
Mol Med Rep ; 28(1)2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37232340

RESUMO

Diabetes­induced cell dysfunction of the retinal pigment epithelium (RPE) contributes to the initiation and progression of diabetic retinopathy (DR). Thioredoxin 1 (Trx1) plays a key role in DR. However, the effect and mechanism of Trx1 on diabetes­induced cell dysfunction of the RPE is not fully understood during DR. In the present study, the effect of Trx1 on this process and its related mechanism were investigated. A Trx1 overexpression cell line, ARPE19­Trx1/LacZ, was constructed and treated with or without high glucose (HG). Flow cytometry was used to analyze apoptosis of these cells and the mitochondrial membrane potential was analyzed using JC­1 staining solution. A DCFH­DA probe was also used to detect the reactive oxygen species (ROS) generation. Western blotting was used to examine the expression of related proteins in ARPE­19 cells after HG treatment. The results demonstrated that the RPE layer was damaged in clinical samples. ROS formation and RPE cell dysfunction increased after HG treatment in vitro. Besides, the expression of mitochondrial­mediated apoptosis related proteins (Bax, apoptosis­inducing factor, cytochrome C, Caspase3 and Caspase9) also increased; however, overexpression of Trx1 attenuated these changes and improved the function of ARPE19 cells. These results indicated that overexpression of Trx1 alleviated diabetes­induced RPE cell dysfunction in DR by attenuating oxidative stress.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Linhagem Celular , Retina/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Apoptose , Retinopatia Diabética/metabolismo , Diabetes Mellitus/metabolismo
6.
Pest Manag Sci ; 79(5): 1768-1776, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36627764

RESUMO

BACKGROUND: Ambient air pollution caused by pesticide drift has received great attention. To accurately evaluate the health risk of inhaled pesticides, bioaccessibility should be considered. However, methods to reliably assess pesticide residues remain limited, hindering the precise estimation of exposure assessment. We aimed to optimize an in vitro method for the inhalation bioaccessibility (IBA) measurement of triazole fungicides and to incorporate this into inhalation exposure assessment during pesticide spraying. RESULTS: The IBA of triazole fungicides increased logarithmically with extraction duration, plateauing after 6 h. The frequency of agitation displayed a similar pattern, whereas the ratio of solid to liquid between 1/1500 and 1/250 was considerably negatively associated. The predicted values (35.9-53.5%) for IBA based on optimized methodological parameters determined using a response surface methodology showed an acceptable deviation from experimental values (30.7-50.8%), suggesting feasibility for in vitro IBA measurement. Incorporating IBA into calculations of inhalation exposure amount (IE) yielded a value of 8.5 × 10-7 -2.1 × 10-5  mg kg-1 day-1 , a 50-68% reduction compared to IE based on total amount. Additionally, the safety exposure threshold was determined for triazole fungicides using benchmark dose modelling of data from lung A549 cell proliferation toxicity assays, and in this context, margin of exposure (MOE) values were calculated to be within an acceptable level. CONCLUSION: This in vitro method supplements bioaccessibility evaluation based on pesticide inhalation exposure, along with the risk to human health. © 2023 Society of Chemical Industry.


Assuntos
Fungicidas Industriais , Resíduos de Praguicidas , Praguicidas , Humanos , Triazóis/toxicidade , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Medição de Risco/métodos
7.
Cell Tissue Res ; 382(3): 477-486, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32783101

RESUMO

Diabetic retinopathy (DR) is a serious neurodegenerative disease that is induced by hyperglycaemia. Oxidative stress, inflammation and endoplasmic reticulum (ER) stress are involved in the development of DR. Sulforaphane (SF) is widely found in cruciferous plants and has a protective effect against retinal neurodegeneration in diabetes, but the mechanism is unclear. In this study, we investigated the mechanism by which SF protects against photoreceptor degeneration in diabetes. In vivo, a mouse model of diabetes was established by streptozotocin (STZ) injection, and the mice were treated with/without SF. Electroretinography (ERG) and H&E staining were used to evaluate retinal function and morphology. In vitro, 661w cells were treated with AGEs with/without SF. Cell viability and apoptosis were analysed by CCK-8 assay and flow cytometry. The expression of proteins and genes was assessed by western blot and qRT-PCR. The amplitude of the a-wave was decreased and the morphology was changed in the diabetic mice, and these changes were delayed by SF treatment. The percentage of apoptotic cells was increased and the cell viability was decreased after the treatment of 661w cells with AGEs. Moreover, the expression of GRP78, Txnip and TNFα was increased, however, this increased expression was reversed by SF treatment via AMPK pathway activation. Taken together, these data show that SF can delay photoreceptor degeneration in diabetes, and the underlying mechanism is related to the inhibition of ER stress, inflammation and Txnip expression through the activation of the AMPK pathway.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Produtos Finais de Glicação Avançada/metabolismo , Isotiocianatos/uso terapêutico , Doenças Neurodegenerativas/complicações , Degeneração Retiniana/tratamento farmacológico , Sulfóxidos/uso terapêutico , Animais , Diabetes Mellitus Experimental , Modelos Animais de Doenças , Chaperona BiP do Retículo Endoplasmático , Isotiocianatos/farmacologia , Masculino , Camundongos , Doenças Neurodegenerativas/patologia , Estreptozocina/efeitos adversos , Sulfóxidos/farmacologia
8.
Sci Prog ; 103(1): 36850420912150, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32188371

RESUMO

This article investigates sliding mode control for a class of continuous-time switched systems with signal quantization, actuator nonlinearity and persistent dwell-time switching that can guarantee the globally uniformly asymptotical stability of the closed-loop system. First, a sliding surface is devised for the switched system and sufficient conditions are proposed to ensure the globally uniformly asymptotical stability of the sliding motion equation by utilizing multiple Lyapunov function technique. Second, the sliding mode control laws, based on the parameters of quantizer, actuator nonlinearity and disturbance, are devised to stabilize the closed-loop systems. Moreover, sufficient conditions are given to guarantee the devised sliding surface's reachability. Finally, the superiority and effectiveness of developed results is illustrated via a numerical simulation.

9.
J Chromatogr A ; 1499: 57-64, 2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28408044

RESUMO

This work reports the development of a multi-residue method for the identification and quantification of 82 veterinary drugs belonging to different chemical classes in swine waste lagoon. The proposed method applies a solid-phase extraction procedure with Oasis PRiME HLB cartridges that combines isolation of the compounds and sample clean-up in a single step. Analysis is performed by ultra-high performance liquid chromatography-tandem mass spectrometry, in one single injection with a chromatographic run time of only 9.5min. Linearity was studied in the range between 1 and 500µgkg-1 using standards prepared both in pure solvent and in the presence of matrix, showing coefficients of determination higher than 0.99 for all the analytes except for cefapirin in matrix. The average recoveries were in the range of 60-110% for most of the compounds tested with inter-day relative standard deviations below 17%. More than 97% of the investigated compounds had less or equal to a 5µgkg-1 quantitation limit in the studied matrix. Finally, the method was used with success to detect and quantify veterinary drugs residues in real samples with sulfonamides, quinolones, and tetracyclines being the most frequently determined compound groups.


Assuntos
Cromatografia Líquida de Alta Pressão , Esgotos/química , Espectrometria de Massas em Tandem , Drogas Veterinárias/análise , Animais , Antibacterianos/análise , Resíduos de Drogas/análise , Quinolonas/análise , Reprodutibilidade dos Testes , Sulfonamidas/análise , Suínos , Tetraciclinas/análise
10.
Food Chem ; 217: 182-190, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27664624

RESUMO

This study describes the development of a multiresidue method for the efficient identification and quantification of nitroimidazoles, nitrofurans, and chloramphenicol in chicken and egg. After derivatization of nitrofuran metabolites, dispersive-solid phase extraction was used for the extraction of target analytes. An optimization strategy involved the selection of sorbents and extraction solutions for dispersive-solid phase extraction in order to achieve acceptably high recoveries and reduce co-extractives in the final extracts. Analytes were determined by ultra-high performance liquid chromatography-tandem mass spectrometry, in one single injection with a chromatographic run time of 7.5min. Mean recoveries ranged from 86.4% to 116.7% and interday precision was lower than 18%. The limits of quantification were between 0.1 and 0.5µg/kg, which were satisfactory to support surveillance monitoring. Finally, the method was applied to real samples, and metabolite of furazolidone, metronidazole and its metabolite, dimetridazole and its metabolite were detected in both chicken and egg samples.


Assuntos
Cloranfenicol/análise , Ovos/análise , Carne/análise , Músculo Esquelético/química , Nitrofuranos/análise , Nitroimidazóis/análise , Animais , Galinhas , Cromatografia Líquida , Dimetridazol/análise , Furazolidona/análise , Metronidazol/análise , Aves Domésticas , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas em Tandem
11.
Artigo em Inglês | MEDLINE | ID: mdl-26894685

RESUMO

A sensitive and reliable method has been developed and validated for the determination of valnemulin in swine and bovine muscle, liver, and kidney using solid-phase extraction (SPE) and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The tissue samples were extracted with mixture solution of acetonitrile and 0.01mol/L hydrochloric acid, defatted by n-hexane, and further cleaned up using SPE cartridges with polymeric sorbent. Gradient UHPLC separation was performed using an Acquity BEH C18 column with water and acetonitrile as the mobile phase. Multiple reaction monitoring mode of two precursor-product ion transitions for valnemulin was used. Mean recoveries from fortified samples ranged from 93.4 to 104.3% with 3.3-10.7% relative standard deviation. The limit of detection and quantification was 0.2 and 1µg/kg for the analyte, respectively.


Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Carne Vermelha/análise , Espectrometria de Massas em Tandem/métodos , Animais , Bovinos , Diterpenos/análise , Inocuidade dos Alimentos , Limite de Detecção , Extração em Fase Sólida/métodos , Suínos
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