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1.
Opt Lett ; 49(3): 614-617, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300072

RESUMO

We report an electro-optic isolator fabricated on thin-film lithium niobate by photolithography-assisted chemo-mechanical etching that shows an isolation of 39.50 dB and an overall fiber-to-fiber loss of 2.6 dB.

2.
Opt Lett ; 48(24): 6348-6351, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099745

RESUMO

We demonstrate on-chip coherent beam combination of two waveguide amplifiers on Er3+-doped thin film lithium niobate (Er:TFLN) platform. Our device is built based on an electro-optic modulator fabricated on Er:TFLN. The output power of the coherently combined amplifiers is measured as high as 12.9 mW, surpassing that of previous single waveguide amplifiers based on an Er3+-doped thin film lithium niobate platform.

3.
Addict Biol ; 26(4): e12969, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33047425

RESUMO

Internet gaming disorder (IGD), a worldwide mental health issue, has been widely studied using neuroimaging techniques during the last decade. Although dysfunctions in resting-state functional connectivity have been reported in IGD, mapping relationships from abnormal connectivity patterns to behavioral measures have not been fully investigated. Connectome-based predictive modeling (CPM)-a recently developed machine-learning approach-has been used to examine potential neural mechanisms in addictions and other psychiatric disorders. To identify the resting-state connections associated with IGD, we modified the CPM approach by replacing its core learning algorithm with a support vector machine. Resting-state functional magnetic resonance imaging (fMRI) data were acquired in 72 individuals with IGD and 41 healthy comparison participants. The modified CPM was conducted with respect to classification and regression. A comparison of whole-brain and network-based analyses showed that the default-mode network (DMN) is the most informative network in predicting IGD both in classification (individual identification accuracy = 78.76%) and regression (correspondence between predicted and actual psychometric scale score: r = 0.44, P < 0.001). To facilitate the characterization of the aberrant resting-state activity in the DMN, the identified networks have been mapped into a three-subsystem division of the DMN. Results suggest that individual differences in DMN function at rest could advance our understanding of IGD and variability in disorder etiology and intervention outcomes.


Assuntos
Comportamento Aditivo/fisiopatologia , Conectoma , Transtorno de Adição à Internet/fisiopatologia , Máquina de Vetores de Suporte , Jogos de Vídeo/psicologia , Adulto , Encéfalo/fisiopatologia , Função Executiva , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiopatologia , Adulto Jovem
4.
Sensors (Basel) ; 19(9)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31052380

RESUMO

With the rapid development of the internet of things (IoT), traditional industries are setting off a massive wave of digitization. In the era of the Internet of Everything, millions of devices and links in IoT pose more significant challenges to data management. Most existing solutions employ centralized systems to control IoT devices, which brings about the privacy and security issues in IoT data management. Recently, blockchain has attracted much attention in the field of IoT due to its decentralization, traceability, and non-tamperability. However, it is non-trivial to apply the current blockchain techniques to IoT due to the lack of scalability and high resource costs. Different blockchain platforms have their particular advantages in the scenario of IoT data management. In this paper, we propose a cross-chain framework to integrate multiple blockchains for efficient and secure IoT data management. Our solution builds an interactive decentralized access model which employs a consortium blockchain as the control station. Other blockchain platforms customized for specific IoT scenarios run as the backbone of all IoT devices. It is equivalent to opening the off-chain channels on the consortium blockchain. Our model merges transactions in these channels for confirmation based on the notary mechanism. Finally, we implement a prototype of the proposed model based on hyperledge Fabric and IOTA Tangle. We evaluate the performance of our method through extensive experiments. The results demonstrate the effectiveness and efficiency of our framework.

5.
J Membr Biol ; 251(1): 91-104, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28975384

RESUMO

Iron is essential for all organisms. Bacteria have devolved sophisticated systems to maintain intracellular iron homeostasis. FpvCDEF(PA2407-2410) has been reported as an ABC transporter involved in pyoverdine-Fe uptake which does not affect growth under iron-limiting condition, when it is deleted in PAO1. In this study, we proved that fpvCDEF and fpvWXYZ(PA2403-2406) constituted an ABC transporter complex containing two operons: fpvWXYZCDE and fpvF. The operon fpvWXYZCDE was regulated by iron negatively and the single gene operon fpvF was constitutively expressed. Inactivation of any one of the components, fpvW, fpvC, fpvD, fpvE, and fpvF, led to increased expression of fpvWXYZCDE suggesting that each component of fpvWXYZCDEF could be involved in iron uptake. The ABC transporter complex encoded by fpvWXYZCDEF plays important roles in growth, oxidative stress resistance, and virulence, since the deletion of fpvWXYZCDEF resulted in defective growth, increased sensitivity to H2O2, and decreased virulence compared with PAO1(ΔfpvCDEF) and the wild type PAO1 under iron-limiting condition.


Assuntos
Proteínas de Bactérias/metabolismo , Ferro/metabolismo , Óperon/genética , Pseudomonas aeruginosa/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/genética , Deficiências de Ferro , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Pseudomonas aeruginosa/genética , Virulência
6.
Hu Li Za Zhi ; 64(3): 33-42, 2017 Jun.
Artigo em Zh | MEDLINE | ID: mdl-28580557

RESUMO

BACKGROUND: Postoperative delirium is a significant complication in elderly patients. The occurrence of delirium may increase the related physical and psychological risks, delay the length of hospital stays, and even lead to death. According to the current evidence-based model, the application of interdisciplinary intervention may effectively prevent delirium, shorten the length of hospital stays, and save costs. PURPOSE: To establish a culturally appropriate interdisciplinary intervention model for preventing postoperative delirium in older Chinese patients. METHODS: The authors adapted the original version of the Hospital Elder Life Program (HELP©) from the Hebrew Senior Life Institute for Aging Research of Harvard University by localizing the content using additional medical resources and translating the modified instrument into Chinese. Furthermore, the final version of this interdisciplinary intervention model for postoperative delirium was developed in accordance with the "guideline of delirium: diagnosis, prevention and management produced by the National Institute for Health and Clinical Excellence in 2010" and the "clinical practice guideline for postoperative delirium in older adults" produced by American geriatrics society in 2014. Finally, the translated instrument was revised and improved using discussions, consultations, and pilot study. RESULTS: The abovementioned procedure generated an interdisciplinary intervention model for preventing postoperative delirium that is applicable to the Chinese medical environment. The content addresses personnel structure and assignment of responsibility; details of interdisciplinary intervention protocols and implementation procedures; and required personnel training. CONCLUSIONS: The revised model is expected to decrease the occurrence of post-operative delirium and other complications in elderly patients, to help them maintain and improve their function, to shorten the length of their hospital stays, and to facilitate recovery.


Assuntos
Delírio/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Idoso , Humanos
7.
Microb Pathog ; 91: 5-17, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26596709

RESUMO

Pseudomonas aeruginosa is an important human pathogen which adapts to changing environment, such as temperature variations and entering host by regulating their gene expression. Here, we report that gene PA0011 in P. aeruginosa PAO1, which encodes a 2-OH-lauroytransferase participating in lipid A biosynthesis, is involved in carbapenem resistance and virulence in a temperature-regulated manner in PAO1. The expression of PA0011 was higher at an environment temperature (21 °C) than that at a body temperature (37 °C). The inactivation of PA0011 rendered increased antibiotic susceptibility and decreased virulence both in vivo and in vitro. The impaired integrity and the decreased stability of the outer membrane were the cause of the increased susceptibility of PAO1(Δ0011) to carbapenem and many other common antibiotics. The reduced endotoxic activity of lipopolysaccharide (LPS) contributed to the decreased virulence both at 21 °C and 37 °C in PAO1 (Δ0011). In addition, we have found that PA0011 repressed the expression of TTSS virulence factors both at transcriptional and translational levels, similar to the effect of O antigen of LPS but unlike any effect of its homologue reported in other bacteria. The effect of PA0011 on resistance to many antibiotics including carbapenem and virulence in P. aeruginosa makes it a target for novel antimicrobial therapies.


Assuntos
Aciltransferases/metabolismo , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/patogenicidade , Sistemas de Secreção Tipo III/metabolismo , Aciltransferases/química , Aciltransferases/genética , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Modelos Animais de Doenças , Drosophila melanogaster , Estabilidade Enzimática , Regulação Bacteriana da Expressão Gênica , Humanos , Masculino , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Temperatura , Sistemas de Secreção Tipo III/genética , Virulência
8.
Microb Pathog ; 101: 126-135, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27746380

RESUMO

Pseudomonas aeruginosa (PAO1) is an important opportunistic pathogen that thrives in various environments. It is known that the structural variations of the lipopolysaccharide (LPS), including lipid A moiety play an important role in encountering environmental changes. Genes PA3242 and PA0011 have recently been reported to be responsible for secondary-acylation of lipid A in P. aeruginosa. In this study, we confirmed that the PA3242-dependant secondary acylation affects the growth, antibiotic resistance and virulence of PAO1 and functions as a more predominant acyltransferase than PA0011. PA3242 mutant showed inhibited growth at 37 °C and inviability at 28 °C in rich medium LB. The inactivation of PA3242 leads to more sensitivity to a wide range of antibiotics than PAO1(ΔPA0011). Moreover, the virulence of PAO1(ΔPA3242) was attenuated more significantly than that of PAO1 and PAO1(ΔPA0011). The outer membrane integrity and stability of PAO1(ΔPA3242) were seriously compromised. Furthermore, PAO1(ΔPA3242) lost most of pilus and exhibited severely damaged cell envelope, which is probably responsible for the deficiency of swimming, swarming and twitching. These results partially explained the decreased antibiotic resistance and attenuated virulence of PAO1(ΔPA3242) compared to PAO1(ΔPA0011) and PAO1. Our study demonstrated that PA3242-dependent secondary acylation of lipid A plays a predominant role in growth, antibiotic resistance and virulence of PAO1 than PA0011.


Assuntos
Aciltransferases/metabolismo , Farmacorresistência Bacteriana , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Acilação , Aciltransferases/genética , Antibacterianos/farmacologia , Meios de Cultura/química , Deleção de Genes , Lipídeo A/metabolismo , Locomoção , Viabilidade Microbiana/efeitos da radiação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos da radiação , Temperatura , Virulência
9.
J Neurosci ; 33(26): 10676-87, 2013 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-23804091

RESUMO

Attention-deficit/hyperactivity disorder (ADHD), which is characterized by core symptoms of inattention and hyperactivity/impulsivity, is one of the most common neurodevelopmental disorders of childhood. Neuroimaging studies have suggested that these behavioral disturbances are associated with abnormal functional connectivity among brain regions. However, the alterations in the structural connections that underlie these behavioral and functional deficits remain poorly understood. Here, we used diffusion magnetic resonance imaging and probabilistic tractography method to examine whole-brain white matter (WM) structural connectivity in 30 drug-naive boys with ADHD and 30 healthy controls. The WM networks of the human brain were constructed by estimating inter-regional connectivity probability. The topological properties of the resultant networks (e.g., small-world and network efficiency) were then analyzed using graph theoretical approaches. Nonparametric permutation tests were applied for between-group comparisons of these graphic metrics. We found that both the ADHD and control groups showed an efficient small-world organization in the whole-brain WM networks, suggesting a balance between structurally segregated and integrated connectivity patterns. However, relative to controls, patients with ADHD exhibited decreased global efficiency and increased shortest path length, with the most pronounced efficiency decreases in the left parietal, frontal, and occipital cortices. Intriguingly, the ADHD group showed decreased structural connectivity in the prefrontal-dominant circuitry and increased connectivity in the orbitofrontal-striatal circuitry, and these changes significantly correlated with the inattention and hyperactivity/impulsivity symptoms, respectively. The present study shows disrupted topological organization of large-scale WM networks in ADHD, extending our understanding of how structural disruptions of neuronal circuits underlie behavioral disturbances in patients with ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/patologia , Encéfalo/patologia , Imagem de Tensor de Difusão/métodos , Processamento de Imagem Assistida por Computador/métodos , Rede Nervosa/patologia , Adolescente , Algoritmos , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Criança , Humanos , Comportamento Impulsivo/patologia , Masculino
10.
Analyst ; 138(6): 1637-40, 2013 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-23361191

RESUMO

We employed 3-aminopropyltriethoxysilane to assist the synthesis of Ag NCs using polyethyleneimine as the template for detecting Hg(2+) by localized surface plasmon resonance light-scattering technology. The developed selective and sensitive method presaged more opportunities for application in environmental systems.


Assuntos
Mercúrio/análise , Nanoestruturas/química , Silanos/química , Prata/química , Ressonância de Plasmônio de Superfície/métodos , Poluentes Químicos da Água/análise , Água Potável/análise , Lagos/análise , Nanoestruturas/ultraestrutura , Propilaminas , Sensibilidade e Especificidade
11.
Front Neurorobot ; 17: 1204418, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719330

RESUMO

Semantic segmentation, which is a fundamental task in computer vision. Every pixel will have a specific semantic class assigned to it through semantic segmentation methods. Embedded systems and mobile devices are difficult to deploy high-accuracy segmentation algorithms. Despite the rapid development of semantic segmentation, the balance between speed and accuracy must be improved. As a solution to the above problems, we created a cross-scale fusion attention mechanism network called CFANet, which fuses feature maps from different scales. We first design a novel efficient residual module (ERM), which applies both dilation convolution and factorized convolution. Our CFANet is mainly constructed from ERM. Subsequently, we designed a new multi-branch channel attention mechanism (MCAM) to refine the feature maps at different levels. Experiment results show that CFANet achieved 70.6% mean intersection over union (mIoU) and 67.7% mIoU on Cityscapes and CamVid datasets, respectively, with inference speeds of 118 FPS and 105 FPS on NVIDIA RTX2080Ti GPU cards with 0.84M parameters.

12.
J Clin Med ; 12(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36769393

RESUMO

Myocardial fibrosis (MF) is a non-reversible process that occurs following acute or chronic myocardial damage. MF worsens myocardial deformation, remodels the heart and raises myocardial stiffness, and is a crucial pathological manifestation in patients with end-stage cardiovascular diseases and closely related to cardiac adverse events. Therefore, early quantitative analysis of MF plays an important role in risk stratification, clinical decision, and improvement in prognosis. With the advent and development of strain imaging modalities in recent years, MF may be detected early in cardiovascular diseases. This review summarizes the clinical usefulness of strain imaging techniques in the non-invasive assessment of MF.

13.
J Clin Med ; 12(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37048609

RESUMO

Right ventricular-pulmonary artery coupling (RV-PA coupling) refers to the relationship between RV contractility and RV afterload. Normal RV-PA coupling is maintained only when RV function and pulmonary vascular resistance are appropriately matched. RV-PA uncoupling occurs when RV contractility cannot increase to match RV afterload, resulting in RV dysfunction and right heart failure. RV-PA coupling plays an important role in the pathophysiology and progression of cardiovascular diseases. Therefore, early and accurate evaluation of RV-PA coupling is of great significance for a patient's condition assessment, clinical decision making, risk stratification, and prognosis judgment. RV-PA coupling can be assessed by using invasive or noninvasive approaches. The aim of this review was to summarize the pathological mechanism and evaluation methods of RV-PA coupling, the advantages and disadvantages of each method, and the application value of RV-PA coupling in various cardiovascular diseases.

14.
Diagnostics (Basel) ; 13(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37761290

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is defined as HF with left ventricular ejection fraction (LVEF) not less than 50%. HFpEF accounts for more than 50% of all HF patients, and its prevalence is increasing year to year with the aging population, with its prognosis worsening. The clinical assessment of cardiac function and prognosis in patients with HFpEF remains challenging due to the normal range of LVEF and the nonspecific symptoms and signs. In recent years, new echocardiographic techniques have been continuously developed, particularly speckle-tracking echocardiography (STE), which provides a sensitive and accurate method for the comprehensive assessment of cardiac function and prognosis in patients with HFpEF. Therefore, this article reviewed the clinical utility of STE in patients with HFpEF.

15.
Diagnostics (Basel) ; 14(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38201397

RESUMO

Pulmonary regurgitation usually leads to right heart dilatation and eventually right heart dysfunction, which is associated with a poor prognosis. Transcatheter pulmonary valve replacement is a developing treatment for pulmonary valve dysfunction that can take the place of traditional surgery and make up for the shortcomings of a large injury. Echocardiography plays a significant role in assessing ventricular function; however, conventional echocardiographic parameters have several limitations. Speckle tracking echocardiography has been regarded as a more accurate tool for quantifying cardiac function than conventional echocardiography. Therefore, the aim of this review was to summarize the application of speckle tracking echocardiography for evaluating right and left ventricular functions in patients after transcatheter pulmonary valve replacement.

16.
ACS Appl Mater Interfaces ; 14(27): 30962-30968, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35759530

RESUMO

1,3,5-Tri(10H-phenothiazin-10-yl)benzene (3PTZ) is endowed with unique redox and photoresponsive characteristics and has been utilized as a p-type redox center for organic battery cathode material and a room-temperature phosphorescence (RTP) material, respectively. Conversely, its exploration in other research fields, particularly organic synthesis, remains unknown. Here, we demonstrate that 3PTZ-POP synthesized via cross-linking of 3PTZ is capable of harvesting visible-light photons and selectively converting solar energy to chemical energy. Specifically, 3PTZ-POP functions as a metal-free and recyclable photocatalyst to promote the sequential C(sp2)-H functionalizations of N-arylacrylamides with readily available trifluoromethylsulfonyl chloride as the radical precursor. An array of 3,3-disubstituted 2-oxindoles bearing a pharmaceutically important CF3 moiety are delivered in moderate to excellent yields under mild and sustainable conditions.

17.
Diagnostics (Basel) ; 12(10)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36292232

RESUMO

Primary cardiac tumors (PCTs) are rare, with benign PCTs being relatively common in approximately 75% of all PCTs. Benign PCTs are usually asymptomatic, and they are found incidentally by imaging. Even if patients present with symptoms, they are usually nonspecific. Before the application of imaging modalities to the heart, our understanding of these tumors is limited to case reports and autopsy studies. The advent and improvement of various imaging technologies have enabled the non-invasive evaluation of benign PCTs. Although echocardiography is the most commonly used imaging examination, it is not the best method to describe the histological characteristics of tumors. At present, cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT) are often used to assess benign PCTs providing detailed information on anatomical and tissue features. In fact, each imaging modality has its own advantages and disadvantages, multimodality imaging uses two or more imaging types to provide valuable complementary information. With the widespread use of multimodality imaging, these techniques play an indispensable role in the management of patients with benign PCTs by providing useful diagnostic and prognostic information to guide treatment. This article reviews the multimodality imaging characterizations of common benign PCTs.

18.
Diagnostics (Basel) ; 12(8)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-36010248

RESUMO

Atrial fibrillation (AF) is the most common arrhythmia with significant morbidity and mortality. Exacerbated by the aging population, the prevalence of AF is gradually increasing. Accurate evaluation of structure and function of left atrium (LA) has important prognostic significance in patients with AF. Echocardiography is the imaging technique of first choice to assess LA structure and function due to its better availability, accessibility and safety over cardiac computed tomography and cardiac magnetic resonance. Therefore, the aim of this review is to summarize the recent research progress of evaluating LA size by three-dimensional echocardiography and LA function by speckle tracking echocardiography (STE) in predicting the occurrence and recurrence of AF and determining the risk of stroke in AF. In addition, we summarized the role of traditional echocardiography in detecting AF patients that are at high risk of heart failure or cardiovascular death.

19.
Diagnostics (Basel) ; 12(2)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35204536

RESUMO

Patients with heart failure (HF) have high morbidity and mortality. Accurate assessment of right ventricular (RV) function has important prognostic significance in patients with HF. However, conventional echocardiographic parameters of RV function have limitations in RV assessments due to the complex geometry of right ventricle. In recent years, speckle tracking echocardiography (STE) has been developed as promising imaging technique to accurately evaluate RV function. RV longitudinal strain (RVLS) using STE, as a sensitive index for RV function evaluation, displays the powerfully prognostic value in patients with HF. Therefore, the aim of the present review was to summarize the utility of RVLS in patients with HF.

20.
Micromachines (Basel) ; 13(3)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35334670

RESUMO

Integrated thin-film lithium niobate (LN) electro-optic (EO) modulators of broad bandwidth, low insertion loss, low cost and high production rate are essential elements in contemporary interconnection industries and disruptive applications. Here, we demonstrated the design and fabrication of a high performance thin-film LN EO modulator using photolithography assisted chemo-mechanical etching (PLACE) technology. Our device shows a 3-dB bandwidth over 50 GHz, along with a comparable low half wave voltage-length product of 2.16 Vcm and a fiber-to-fiber insertion loss of 2.6 dB. The PLACE technology supports large footprint, high fabrication uniformity, competitive production rate and extreme low device optical loss simultaneously, our result shows promising potential for developing high-performance large-scale low-loss photonic integrated devices.

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