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1.
Huan Jing Ke Xue ; 44(9): 5222-5230, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699840

RESUMO

CuFeO2-modified biochars were prepared through co-precipitation and hydrothermal methods, and the composites had high efficiency removal for tetracycline (TC) from water. The CuFeO2-modified biochar with a 2:1 mass ratio of CuFeO2 to BC450 (CuFeO2/BC450=2:1) demonstrated the best adsorption performance. The kinetic process of TC adsorption by CuFeO2/BC450=2:1 was well fitted with the intraparticle diffusion model, suggesting that the adsorption process was controlled by film and pore diffusion. Under the condition of neutral pH and 298 K, the maximum adsorption capacity of the Langmuir model of CuFeO2/BC450=2:1 was 82.8 mg·g-1, which was much greater than that of BC450 (13.7 mg·g-1) and CuFeO2(14.8 mg·g-1). The thermodynamic data suggested that TC sorption onto CuFeO2/BC450=2:1 was a spontaneous and endothermic process. The removal of TC by CuFeO2/BC450=2:1 increased first and then decreased with increasing pH, and the maximum adsorption occurred under the neutral condition. The strong adsorption of TC by CuFeO2/BC450=2:1 could be attributed to better porosity, larger specific surface area, and more active sites (e.g., functional groups and charged surfaces). This work provided an efficient magnetic adsorbent for removing antibiotics.


Assuntos
Antibacterianos , Tetraciclina , Adsorção , Termodinâmica
3.
Biomed Res Int ; 2019: 2045432, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31871932

RESUMO

Lung segmentation in high-resolution computed tomography (HRCT) images is necessary before the computer-aided diagnosis (CAD) of interstitial lung disease (ILD). Traditional methods are less intelligent and have lower accuracy of segmentation. This paper develops a novel automatic segmentation model using radiomics with a combination of hand-crafted features and deep features. The study uses ILD Database-MedGIFT from 128 patients with 108 annotated image series and selects 1946 regions of interest (ROI) of lung tissue patterns for training and testing. First, images are denoised by Wiener filter. Then, segmentation is performed by fusion of features that are extracted from the gray-level co-occurrence matrix (GLCM) which is a classic texture analysis method and U-Net which is a standard convolutional neural network (CNN). The final experiment result for segmentation in terms of dice similarity coefficient (DSC) is 89.42%, which is comparable to the state-of-the-art methods. The training performance shows the effectiveness for a combination of texture and deep radiomics features in lung segmentation.


Assuntos
Diagnóstico por Computador/métodos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Bases de Dados Factuais , Feminino , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Redes Neurais de Computação
4.
J Biol Chem ; 292(44): 17991-18005, 2017 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-28912273

RESUMO

The neuroligin (Nlg) family of neural cell adhesion molecules is thought to be required for synapse formation and development and has been linked to the development of autism spectrum disorders in humans. In Drosophila melanogaster, mutations in the neuroligin 1-3 genes have been reported to induce synapse developmental defects at neuromuscular junctions (NMJs), but the role of neuroligin 4 (dnlg4) in synapse development has not been determined. Here, we report that the Drosophila neuroligin 4 (DNlg4) is different from DNlg1-3 in that it presynaptically regulates NMJ synapse development. Loss of dnlg4 results in reduced growth of NMJs with fewer synaptic boutons. The morphological defects caused by dnlg4 mutant are associated with a corresponding decrease in synaptic transmission efficacy. All of these defects could only be rescued when DNlg4 was expressed in the presynapse of NMJs. To understand the basis of DNlg4 function, we looked for genetic interactions and found connections with the components of the bone morphogenetic protein (BMP) signaling pathway. Immunostaining and Western blot analyses demonstrated that the regulation of NMJ growth by DNlg4 was due to the positive modulation of BMP signaling by DNlg4. Specifically, BMP type I receptor thickvein (Tkv) abundance was reduced in dnlg4 mutants, and immunoprecipitation assays showed that DNlg4 and Tkv physically interacted in vivo Our study demonstrates that DNlg4 presynaptically regulates neuromuscular synaptic growth via the BMP signaling pathway by modulating Tkv.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Proteínas do Tecido Nervoso/metabolismo , Neurogênese , Junção Neuromuscular/metabolismo , Terminações Pré-Sinápticas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Animais Geneticamente Modificados , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/agonistas , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Moléculas de Adesão Celular Neuronais/genética , Proteínas de Drosophila/agonistas , Proteínas de Drosophila/genética , Técnicas de Inativação de Genes , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Mutação , Proteínas do Tecido Nervoso/genética , Junção Neuromuscular/enzimologia , Junção Neuromuscular/ultraestrutura , Terminações Pré-Sinápticas/enzimologia , Terminações Pré-Sinápticas/ultraestrutura , Multimerização Proteica , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Sinapses/enzimologia , Sinapses/metabolismo , Sinapses/ultraestrutura , Transmissão Sináptica
5.
Dev Cell ; 41(1): 94-106.e4, 2017 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-28366281

RESUMO

Columnar restriction of neurites is critical for forming nonoverlapping receptive fields and preserving spatial sensory information from the periphery in both vertebrate and invertebrate nervous systems, but the underlying molecular mechanisms remain largely unknown. Here, we demonstrate that Drosophila homolog of α-neurexin (DNrx) plays an essential role in columnar restriction during L4 axon branching. Depletion of DNrx from L4 neurons resulted in misprojection of L4 axonal branches into neighboring columns due to impaired ephrin clustering. The proper ephrin clustering requires its interaction with the intracellular region of DNrx. Furthermore, we find that Drosophila neuroligin 4 (DNlg4) in Tm2 neurons binds to DNrx and initiates DNrx clustering in L4 neurons, which subsequently induces ephrin clustering. Our study demonstrates that DNrx promotes ephrin clustering and reveals that ephrin/Eph signaling from adjacent L4 neurons restricts axonal branches of L4 neurons in columns.


Assuntos
Axônios/metabolismo , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Membrana/metabolismo , Animais , Mutação/genética , Ligação Proteica , Pupa/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-24125328

RESUMO

Characterizing complex patterns arising from horizontal oil-water two-phase flows is a contemporary and challenging problem of paramount importance. We design a new multisector conductance sensor and systematically carry out horizontal oil-water two-phase flow experiments for measuring multivariate signals of different flow patterns. We then infer multivariate recurrence networks from these experimental data and investigate local cross-network properties for each constructed network. Our results demonstrate that a cross-clustering coefficient from a multivariate recurrence network is very sensitive to transitions among different flow patterns and recovers quantitative insights into the flow behavior underlying horizontal oil-water flows. These properties render multivariate recurrence networks particularly powerful for investigating a horizontal oil-water two-phase flow system and its complex interacting components from a network perspective.

7.
J Neurosci ; 33(39): 15545-54, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24068821

RESUMO

Sleep is an essential and evolutionarily conserved behavior that is closely related to synaptic function. However, whether neuroligins (Nlgs), which are cell adhesion molecules involved in synapse formation and synaptic transmission, are involved in sleep is not clear. Here, we show that Drosophila Nlg4 (DNlg4) is highly expressed in large ventral lateral clock neurons (l-LNvs) and that l-LNv-derived DNlg4 is essential for sleep regulation. GABA transmission is impaired in mutant l-LNv, and sleep defects in dnlg4 mutant flies can be rescued by genetic manipulation of GABA transmission. Furthermore, dnlg4 mutant flies exhibit a severe reduction in GABAA receptor RDL clustering, and DNlg4 associates with RDLs in vivo. These results demonstrate that DNlg4 regulates sleep through modulating GABA transmission in l-LNvs, which provides the first known link between a synaptic adhesion molecule and sleep in Drosophila.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/fisiologia , Sono , Transmissão Sináptica , Ácido gama-Aminobutírico/metabolismo , Animais , Moléculas de Adesão Celular Neuronais/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Neurônios/metabolismo , Neurônios/fisiologia , Receptores de GABA-A/metabolismo
8.
Rev Sci Instrum ; 82(3): 034707, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21456776

RESUMO

Nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR)-based chemical analysis systems have been widely utilized in various areas such as medicine, security, and academic research. In these applications, the power amplifier stage plays a key role in generating the required oscillating magnetic fields within a radio frequency coil that serves as the probe. However, the bulky size and relatively low efficiency of the traditional power amplification schemes employed present a bottleneck for the realization of compact sized and portable NMR and NQR systems. To address this problem, this work presents a class D voltage-switching power amplification scheme with novel fast-start and fast-stop functions that are suitable for generating ideal NMR and NQR excitation signals. Compared to the traditional analog power amplifiers (PAs), the proposed switched-mode PA can achieve significant improvement on the power efficiency as well as the physical volume. A PA circuit for portable NQR-based explosive detection systems has been designed and built using the proposed scheme with 1 kW possible maximum output power and 10 MHz maximum operating frequency. Test results show that the presented PA achieves more than 60% measured efficiency within a highly compact volume while sustaining fast start and stop of excitation signals in the order of microseconds.

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