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1.
Sensors (Basel) ; 24(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39001143

RESUMO

Mobile robots play an important role in the industrial Internet of Things (IIoT); they need effective mutual communication between the cloud and themselves when they move in a factory. By using the sensor nodes existing in the IIoT environment as relays, mobile robots and the cloud can communicate through multiple hops. However, the mobility and delay sensitivity of mobile robots bring new challenges. In this paper, we propose a dynamic cooperative transmission algorithm with mutual information accumulation to cope with these two challenges. By using rateless coding, nodes can reduce the delay caused by retransmission under poor channel conditions. With the help of mutual information accumulation, nodes can accumulate information faster and reduce delay. We propose a two-step dynamic algorithm, which can obtain the current routing path with low time complexity. The simulation results show that our algorithm is better than the existing heuristic algorithm in terms of delay.

2.
Angew Chem Int Ed Engl ; 63(31): e202404093, 2024 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-38727540

RESUMO

Accurate visualization of tumor microenvironment is of great significance for personalized medicine. Here, we develop a near-infrared (NIR) fluorescence/photoacoustic (FL/PA) dual-mode molecular probe (denoted as NIR-CE) for distinguishing tumors based on carboxylesterase (CE) level by an analyte-induced molecular transformation (AIMT) strategy. The recognition moiety for CE activity is the acetyl unit of NIR-CE, generating the pre-product, NIR-CE-OH, which undergoes spontaneous hydrogen atom exchange between the nitrogen atoms in the indole group and the phenol hydroxyl group, eventually transforming into NIR-CE-H. In cellular experiments and in vivo blind studies, the human hepatoma cells and tumors with high level of CE were successfully distinguished by both NIR FL and PA imaging. Our findings provide a new molecular imaging strategy for personalized treatment guidance.


Assuntos
Carboxilesterase , Medicina de Precisão , Humanos , Carboxilesterase/metabolismo , Sondas Moleculares/química , Corantes Fluorescentes/química , Imagem Óptica , Animais
3.
J Cell Physiol ; 238(5): 1036-1045, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36922748

RESUMO

Periodontitis is a chronic immune inflammatory disease that can lead to the destruction and loss of the tooth-supporting apparatus. During this process, the balance between bone absorption mediated by osteoclasts and bone formation mediated by osteoblasts is damaged. Consistent with previous studies, we observed that depletion of cylindromatosis (CYLD) resulted in an osteoporotic bone phenotype. However, the effect of CYLD deficiency on periodontitis is undetermined. Here, we investigated whether CYLD affects periodontal tissue homeostasis in experimental periodontitis in Cyld knockout (KO) mice, and we explored the underlying mechanisms. Interestingly, we discovered significant alveolar bone density loss and severely reduced alveolar bone height in Cyld KO mice with experimentally induced periodontitis. We observed increased osteoclast number and activity in both the femurs and alveolar bones, accompanied by the downregulation of osteogenesis genes and upregulation of osteoclastogenesis genes of alveolar bones in ligatured Cyld KO mice. Taken together, our findings demonstrate that the deletion of CYLD in mice plays a vital role in the pathogenesis of periodontal bone loss and suggest that CYLD might exert an ameliorative effect on periodontal inflammatory responses.


Assuntos
Perda do Osso Alveolar , Periodontite , Camundongos , Animais , Perda do Osso Alveolar/genética , Osteogênese , Osteoclastos/patologia , Periodontite/genética , Periodontite/patologia , Osso e Ossos/patologia , Enzima Desubiquitinante CYLD/genética
4.
Sensors (Basel) ; 23(16)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37631755

RESUMO

With the continuous progress and application of robotics technology, the importance of mobile robots capable of adapting to specialized work environments is gaining prominence. Among them, achieving precise and stable control of AGVs (Automated Guided Vehicles) stands as a paramount task propelling the advancement of mobile robotics. Consequently, this study devises a control system that enables AGVs to attain stable and accurate motion through equipment connection and debugging, kinematic modeling of the four-wheel steering AGV, and a selection and comparative analysis of motion control algorithms. The effectiveness of the Stanley-PID control algorithm in guiding the motion of a four-wheel steering AGV is validated through MATLAB 2021a simulation software. The simulation results illustrate the outstanding stability and precise control capabilities of the Stanley-PID algorithm.

5.
Int J Mol Sci ; 24(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36674446

RESUMO

Porcine reproductive and respiratory syndrome (PRRS) is a vertically transmitted reproductive disorder that is typically characterized by miscarriage, premature birth, and stillbirth in pregnant sows after infection. Such characteristics indicate that PRRSV can infect and penetrate the porcine placental barrier to infect fetus piglets. The porcine trophoblast is an important component of the placental barrier, and secretes various hormones, including estrogen and progesterone, to maintain normal pregnancy and embryonic development during pregnancy. It is conceivable that the pathogenic effects of PRRSV infection on porcine trophoblast cells may lead to reproductive failure; however, the underlying detailed mechanism of the interaction between porcine trophoblast (PTR2) cells and PRRSV is unknown. Therefore, we conducted genome-wide mRNA and long non-coding RNA (lncRNA) analysis profiling in PRRSV-infected PTR2. The results showed that 672 mRNAs and 476 lncRNAs were significantly different from the control group after viral infection. Target genes of the co-expression and co-location of differential mRNAs and lncRNAs were enriched by GO (gene ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis, revealing that most of the pathways were involved in cell nutrient metabolism, cell proliferation, and differentiation. Specifically, the estrogen signaling pathway, the PI3K (PhosphoInositide-3 Kinase)-Akt (serine/threonine kinase) signaling pathway, and the insulin secretion related to embryonic development were selected for analysis. Further research found that PRRSV inhibits the expression of G-protein-coupled estrogen receptor 1 (GPER1), thereby reducing estrogen-induced phosphorylation of AKT and the mammalian target of rapamycin (mTOR). The reduction in the phosphorylation of AKT and mTOR blocks the activation of the GPER1- PI3K-AKT-mTOR signaling pathway, consequently restraining insulin secretion, impacting PTR2 cell proliferation, differentiation, and nutrient metabolism. We also found that PRRSV triggered trophoblast cell apoptosis, interrupting the integrity of the placental villus barrier. Furthermore, the interaction network diagram of lncRNA, regulating GPER1 and apoptosis-related genes, was constructed, providing a reference for enriching the functions of these lncRNA in the future. In summary, this article elucidated the differential expression of mRNA and lncRNA in trophoblast cells infected with PRRSV. This infection could inhibit the PI3K-AKT-mTOR pathway and trigger apoptosis, providing insight into the mechanism of the vertical transmission of PRRSV and the manifestation of reproductive failure.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , RNA Longo não Codificante , Suínos , Animais , Feminino , Gravidez , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , RNA Longo não Codificante/genética , Trofoblastos , RNA Mensageiro/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt , Placenta , Síndrome Respiratória e Reprodutiva Suína/genética , Serina-Treonina Quinases TOR , Estrogênios , Mamíferos/genética
6.
Anal Chem ; 94(7): 3227-3234, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35129959

RESUMO

Early detection of human neutrophil elastase (HNE), the potential biomarker of lung cancer, is crucial for the accurate diagnosis and evaluation of lung cancer. Currently, little progress of HNE-activated probes has been made for in vivo imaging. Herein, assisted by probe-active pocket match engineering, we synthesized a series of near-infrared fluorescence (NIRF) and photoacoustic (PA) duplex imaging probes by conjugating diverse fluorinated amide chains onto hemi-cyanine. Finally, we identified that probe 2 (denoted as LET-8), with the pentafluoroethyl group, is a superior probe to detect HNE with the best selectivity as well as good response ability and thus successfully realized NIRF/PA duplex imaging of HNE activity both in vitro and in vivo.


Assuntos
Elastase de Leucócito , Sondas Moleculares , Biomarcadores , Diagnóstico por Imagem , Corantes Fluorescentes , Humanos , Neoplasias Pulmonares/diagnóstico , Imagem Molecular/métodos , Técnicas Fotoacústicas , Espectrometria de Fluorescência , Espectroscopia de Luz Próxima ao Infravermelho
7.
Anal Chem ; 94(40): 13770-13776, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36173742

RESUMO

Overexpressing human NAD(P)H:quinone oxidoreductase 1 (hNQO1) in lung cancer tissues is deemed to be an attractive biomarker, which is directly connected to cancerous pathological processes. Monitoring of hNQO1 activity is crucial to early diagnosis and prognosis of lung cancer. In this study, an activatable hemi-cyanine dye-based probe (denoted as the LET-10 probe) was synthesized for near-infrared fluorescence (NIRF) and ratiometric photoacoustic (RPA) imaging of hNQO1. LET-10 can realize the NIRF and PA signal opening in the presence of hNQO1. Taking the octabutoxy naphthalocyanine in the LET-10 probe as a built-in reference signal, the LET-10 probe further demonstrated a double-signal self-calibration process for RPA imaging. Finally, the LET-10 probe was successfully applied for NIRF/RPA duplex imaging in the hNQO1-positive A549 lung cancer model, which suggests that the LET-10 probe is a promising tool for in vivo hNQO1 detection, especially for lung cancer diagnosis.


Assuntos
Neoplasias Pulmonares , NAD , Fluorescência , Corantes Fluorescentes , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Quinonas
8.
Langmuir ; 38(16): 4894-4905, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35421315

RESUMO

Surface-enhanced Raman scattering (SERS) has attracted attention because of its enormous potential to detect molecules with low concentrations. The method of fabricating SERS substrates is of great importance for improving the detection resolution. However, SERS substrates with different triangular pyramid tips fabricated by using the tip-based nanoindentation method has not been reported. Here, we prepared arrayed micro/nanocavities on copper-based graphene using the continuous indentation method with a Berkovich tip and a cube-corner tip, which have different face angles. Gold nanoparticles were then sputtered onto the graphene-copper micro/nanocavities to form the Au@GR@Cu micro/nanocavities SERS substrates. The substrates formed using the Berkovich tip and cube-corner tip were labeled B2-B9 and C2-C9, respectively, in which the numbers indicate the machining feed. Rhodamine 6G (R6G) was employed, and the Raman intensities of R6G on the differently arrayed Au@GR@Cu micro/nanocavities were measured. The Raman intensities of R6G were stronger on the pile-ups than on the inverted triangular pyramid cavities. The Raman intensities of R6G were highest on the C2 and B2 structures and lowest on the C9 and B9 structures. The Raman intensities of R6G on the arrayed Au@GR@Cu micro/nanocavities fabricated by the cube-corner tip were stronger than those on the arrayed Au@GR@Cu micro/nanocavities fabricated using the Berkovich tip with the same machining feed. In addition, the electric field intensity and distribution of the B9 and C9 arrayed Au@GR@Cu were simulated using Comsol software. Au@GR@Cu structures fabricated by the cube-corner tip were generated with higher electric field intensities. Furthermore, the relative standard deviations at 1362 cm-1 of R6G were 6.19 and 6.62% on the C2 and C4 surfaces, respectively, showing good homogeneity. The SERS spectra of 10-9 mol/L malachite green solution and 10-6 mol/L carbaryl solution were recognized on the C1, C2, and C4 surfaces on day 1 and after 3 months, respectively. After storage at room temperature for 3 months, the reductions in the Raman intensities were less than 10%, indicating excellent stability. The results showed that the arrayed Au@GR@Cu micro/nanocavities fabricated using the cube-corner tip performed better than those fabricated using the Berkovich tip and exhibited excellent uniformity, availability, and stability, providing great potential for detecting pesticides at low concentrations.

9.
Arch Virol ; 166(8): 2141-2149, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34009439

RESUMO

Porcine circovirus type 3 (PCV3) has been widely detected throughout the world since it was first discovered on pig farms in 2015. PCV3 is closely associated with cardiac and multisystem inflammation, respiratory disease, congenital tremors, myocarditis, diarrhea, encephalitis and neurologic disease, and periarteritis. However, there have been few reports on the relationship between PCV3 and inflammatory pathways. The NF-κB signaling pathway plays an important role in the defense against viral infection. Here, we demonstrate that the capsid protein (Cap) of PCV3 plays a key role in the activation of NF-κB signaling in HEK-293T cells. Furthermore, PCV3 Cap promotes the mRNA expression of the pro-inflammatory cytokines IL6 and TNFα. In addition, PCV3 Cap promotes RIG-I and MDA5 mRNA expression in RIG-like receptor (RLR) signaling and MyD88 mRNA expression in Toll-like receptor (TLR) signaling but does not influence TRIF mRNA expression in TLR signaling. These results show that PCV3 Cap activates NF-κB signaling, possibly through the RLR and the TLR signaling pathways. This work illustrates that PCV3 Cap activates NF-κB signaling and thus may provide a basis for the pathogenesis of PCV3 and the innate immunity of the host.


Assuntos
Proteínas do Capsídeo/imunologia , Circovirus/metabolismo , Citocinas/genética , Transdução de Sinais , Circovirus/imunologia , Proteína DEAD-box 58/genética , Células HEK293 , Humanos , Helicase IFIH1 Induzida por Interferon/genética , Interleucina-6/genética , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/genética
10.
Molecules ; 27(1)2021 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-35011360

RESUMO

Anticancer treatment is largely affected by the hypoxic tumor microenvironment (TME), which causes the resistance of the tumor to radiotherapy. Combining radiosensitizer compounds and O2 self-enriched moieties is an emerging strategy in hypoxic-tumor treatments. Herein, we engineered GdW10@PDA-CAT (K3Na4H2GdW10O36·2H2O, GdW10, polydopamine, PDA, catalase, CAT) composites as a radiosensitizer for the TME-manipulated enhancement of radiotherapy. In the composites, Gd (Z = 64) and W (Z = 74), as the high Z elements, make X-ray gather in tumor cells, thereby enhancing DNA damage induced by radiation. CAT can convert H2O2 to O2 and H2O to enhance the X-ray effect under hypoxic TME. CAT and PDA modification enhances the biocompatibility of the composites. Our results showed that GdW10@PDA-CAT composites increased the efficiency of radiotherapy in HT29 cells in culture. This polyoxometalates and O2 self-supplement composites provide a promising radiosensitizer for the radiotherapy field.


Assuntos
Gadolínio/química , Nanocompostos/química , Radiossensibilizantes/química , Hipóxia Tumoral/efeitos da radiação , Tungstênio/química , Ânions/química , Materiais Biocompatíveis/química , Catalase/metabolismo , Linhagem Celular Tumoral , Células HT29 , Humanos , Peróxido de Hidrogênio/metabolismo , Indóis/química , Oxigênio/metabolismo , Polieletrólitos/química , Polímeros/química , Radiossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral
11.
Sensors (Basel) ; 20(21)2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33171820

RESUMO

Component analysis plays an important role in food production, pharmaceutics and agriculture. Nanozymes have attracted wide attention in analytical applications for their enzyme-like properties. In this work, a fluorometric method is described for the determination of thiamine (TH) (vitamin B1) based on hemoglobin-Cu3(PO4)2 nanoflowers (Hb-Cu3(PO4)2 NFs) with peroxidase-like properties. The Hb-Cu3(PO4)2 NFs catalyzed the decomposition of H2O2 into ·OH radicals in an alkaline solution that could efficiently react with nonfluorescent thiamine to fluoresce thiochrome. The fluorescence of thiochrome was further enhanced with a nonionic surfactant, Tween 80. Under optimal reaction conditions, the linear range for thiamine was from 5 × 10-8 to 5 × 10-5 mol/L. The correlation coefficient for the calibration curve and the limit of detection (LOD) were 0.9972 and 4.8 × 10-8 mol/L, respectively. The other vitamins did not bring about any obvious changes in fluorescence. The developed method based on hybrid nanoflowers is specific, pragmatically simple and sensitive, and has potential for application in thiamine detection.


Assuntos
Fluorometria , Peróxido de Hidrogênio , Nanoestruturas , Tiamina/análise , Hemoglobinas , Peroxidase
12.
Molecules ; 25(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353184

RESUMO

Fungal infections pose a serious threat to human health. Polyoxometalates (POMs) are metal-oxygen clusters with potential application in the control of microbial infections. Herein, the Ag3PW12O40 composites have been synthesized and verified by Fourier transform infrared (FT-IR) spectrum, transmission electron microscopy (TEM), scanning electron microscope (SEM), elemental analysis, and X-ray diffraction (XRD). The antifungal activities of Ag3PW12O40 were screened in 19 Candida species strains through the determination of minimum inhibitory concentration (MIC) by the microdilution checkerboard technique. The minimum inhibitory concentration (MIC50) values of Ag3PW12O40 are 2~32 µg/mL to the Candida species. The MIC80 value of Ag3PW12O40 to resistant clinical isolates C. albicans HL963 is 8 µg/mL, which is lower than the positive control, fluconazole (FLC). The mechanism against C. albicans HL963 results show that Ag3PW12O40 can decrease the ergosterol content. The expressions of ERG1, ERG7, and ERG11, which impact on the synthesis of ergosterol, are all prominently upregulated by Ag3PW12O40. It indicates that Ag3PW12O40 is a candidate in the development of new antifungal agents.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Fósforo/farmacologia , Prata/farmacologia , Compostos de Tungstênio/farmacologia , Antifúngicos/química , Candida/crescimento & desenvolvimento , Farmacorresistência Fúngica/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Fósforo/química , Prata/química , Propriedades de Superfície , Compostos de Tungstênio/química
13.
Proc Natl Acad Sci U S A ; 113(50): E8031-E8040, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27911771

RESUMO

Synaptic soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) couple their stepwise folding to fusion of synaptic vesicles with plasma membranes. In this process, three SNAREs assemble into a stable four-helix bundle. Arguably, the first and rate-limiting step of SNARE assembly is the formation of an activated binary target (t)-SNARE complex on the target plasma membrane, which then zippers with the vesicle (v)-SNARE on the vesicle to drive membrane fusion. However, the t-SNARE complex readily misfolds, and its structure, stability, and dynamics are elusive. Using single-molecule force spectroscopy, we modeled the synaptic t-SNARE complex as a parallel three-helix bundle with a small frayed C terminus. The helical bundle sequentially folded in an N-terminal domain (NTD) and a C-terminal domain (CTD) separated by a central ionic layer, with total unfolding energy of ∼17 kBT, where kB is the Boltzmann constant and T is 300 K. Peptide binding to the CTD activated the t-SNARE complex to initiate NTD zippering with the v-SNARE, a mechanism likely shared by the mammalian uncoordinated-18-1 protein (Munc18-1). The NTD zippering then dramatically stabilized the CTD, facilitating further SNARE zippering. The subtle bidirectional t-SNARE conformational switch was mediated by the ionic layer. Thus, the t-SNARE complex acted as a switch to enable fast and controlled SNARE zippering required for synaptic vesicle fusion and neurotransmission.


Assuntos
Proteínas SNARE/química , Sequência de Aminoácidos , Animais , Fusão de Membrana , Camundongos , Microscopia de Força Atômica , Simulação de Dinâmica Molecular , Proteínas Munc18/química , Proteínas Munc18/fisiologia , Pinças Ópticas , Conformação Proteica , Domínios Proteicos , Dobramento de Proteína , Estabilidade Proteica , Proteínas Qa-SNARE/química , Proteínas Qa-SNARE/fisiologia , Proteínas SNARE/genética , Proteínas SNARE/fisiologia , Transmissão Sináptica/fisiologia , Proteína 25 Associada a Sinaptossoma/química , Proteína 25 Associada a Sinaptossoma/fisiologia , Proteína 2 Associada à Membrana da Vesícula/química , Proteína 2 Associada à Membrana da Vesícula/fisiologia
14.
Med Sci Monit ; 24: 4121-4127, 2018 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-29908129

RESUMO

BACKGROUND The role of miR-181a in the development of cardiac disease and in particular, myocardial fibrosis following myocardial infarction (MI) remains unknown. The aim of this study was to explore the role of miR-181a in myocardial fibrosis in a rat model of MI and the expression of TGF-ß receptor III (TßRIII). MATERIAL AND METHODS Forty adult male Wistar rats were randomly divided into an MI model group (n=30) and a control group with (n=10). The rat MI model involved ligating the left anterior descending (LAD) coronary artery in the model group; the control group was treated with a sham operation. Cardiac function was assessed using cardiac ultrasound. Myocardial fibroblasts were extracted from the rat hearts and transfected with a miR-mimic or miR-inhibitor, and cell growth was measured using an MTT assay. The level of miR-181a expression was detected using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blots. RESULTS miR-181a expression was significantly increased during the progression of MI (P<0.05). Over-expression of miR-181a was associated with increased deposition of extracellular matrix (ECM) components, collagen I and fibronectin. This effect was reversed with the use of a miR-181a inhibitor (P<0.05). Upregulation of miR-181a suppressed the expression of TGF-ß receptor III (TßRIII) by binding with 3'-UTR. CONCLUSIONS In this rat model of MI, the findings were that miR-181a had a role in the progression of myocardial fibrosis. The findings require further studies to determine whether miR-181a might provide a novel therapeutic target to limit myocardial fibrosis following MI.


Assuntos
Fibrose Endomiocárdica/genética , MicroRNAs/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Animais , Proliferação de Células/fisiologia , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Fibrose Endomiocárdica/metabolismo , Fibrose Endomiocárdica/patologia , Masculino , MicroRNAs/biossíntese , MicroRNAs/genética , Infarto do Miocárdio/metabolismo , Proteoglicanas/biossíntese , Proteoglicanas/genética , Ratos , Ratos Wistar , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Receptores de Fatores de Crescimento Transformadores beta/genética
15.
Appl Opt ; 56(25): 7138-7145, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29047974

RESUMO

The wavelet-domain de-noising technique has many applications in terahertz time-domain spectroscopy (THz-TDS). However, it requires a complex procedure for the selection of the optimal wavelet basis and threshold, which varies for different materials. Inappropriate selections can lead to de-noising failure. Here, we propose the Mean Estimation Empirical Mode Decomposition (ME-EMD) de-noising method for THz-TDS. First, the THz-TDS signal and the collected reference noise are decomposed into the intrinsic mode functions (IMFs); second, the maximum and mean absolute values of the noise IMF amplitudes are calculated and defined as the adaptive threshold and adaptive estimated noise value, respectively; finally, these thresholds and estimated noise values are utilized to filter the noise from the signal IMFs and reconstruct the THz-TDS signal. We also calculate the signal-to-noise ratio (SNR) and mean square error (MSE) for the ME-EMD method, the "db7" wavelet basis, and the "sym8" wavelet basis after de-noising in both the simulation and the real sample experiments. Both theoretical analysis and experimental results demonstrated that the new ME-EMD method is a simple, effective, and high-stability de-noising tool for THz-TDS pulses. The measured refractive index curves are compared before and after de-noising and demonstrated that the de-noising process is necessary and useful for measuring the optical constants of a sample.

16.
Microsc Microanal ; 22(3): 565-75, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27142307

RESUMO

The scanning electron microscope provides a platform for subnanometer resolution characterization of material morphology with excellent topographic and chemical contrast dependent on the used detectors. For imaging applications, the predominantly utilized signals are secondary electrons (SEs) and backscattered electrons (BSEs) that are emitted from the sample surface. Recent advances in detector technology beyond the traditional Everhart-Thornley geometry have enabled the simultaneous acquisition and discrimination of SE and BSE signals. This study demonstrates the imaging capabilities of a recently introduced new detector system that consists of the combination of two in-lens (I-L) detectors and one in-column (I-C) detector. Coupled with biasing the sample stage to reduce electron-specimen interaction volumes, this trinity of detector geometry allows simultaneous acquisition of signals to distinguish chemical contrast from topographical changes of the sample, including the identification of surface contamination. The I-C detector provides 4× improved topography, whereas the I-L detector closest to the sample offers excellent simultaneous chemical contrast imaging while not limiting the minimization of working distance to obtain optimal lateral resolution. Imaging capabilities and contrast mechanisms for all three detectors are discussed quantitatively in direct comparison to each other and the conventional Everhart-Thornley detector.

17.
Waste Manag Res ; 34(5): 465-73, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26987735

RESUMO

Housefly larvae (Musca domestica) composting has been increasingly adopted as an efficient practice to achieve value-added swine manure bioconversion, but few researches have evaluated the features of compost maturity by examining the biochemical compositions of dissolved organic matter (DOM) in compost. Here, we adopted spectrum fingerprint technologies to explore the related transformation mechanisms of DOM in compost by conducting field investigations in a full-scale housefly larvae composting farm. The 1-week composting with larvae significantly decreased DOM concentrations from 192.9 to 77.1 g kg(-1) The hydrolysis of proteins and lipids were enhanced during composting, as well as a build-up of aromatic substances, while contents of fulvic- and humic-like substances were augmented on Day 5 and Day 6 (ranged from 0.04 to 0.65 and 0.11 to 0.59 for Fmax, respectively). Compared with traditional composting without the aid of larvae, the stronger biodegradation of DOM and the subsequent formation of humus in compost, led to a higher level of aromaticity and humification under housefly larvae bioconversion, generating a more stable bio-product for downstream utilisation.


Assuntos
Moscas Domésticas , Larva , Esterco , Solo/química , Animais , Biodegradação Ambiental , Reatores Biológicos , China , Hidrólise , Espectroscopia de Ressonância Magnética , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos
18.
J BUON ; 21(1): 118-24, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27061539

RESUMO

PURPOSE: The aim of this study was to compare the surgical and long-term outcomes of laparoscopic and open gastrectomy with radical intent for locally advanced gastric carcinoma in case-controlled patient groups using the propensity score. METHODS: Between January 2009 and December 2014, 389 patients who underwent gastrectomy with radical intent for locally advanced gastric carcinoma were enrolled. These patients were divided into two groups according to the method of operation: the laparoscopy group (patients who underwent laparoscopic gastrectomy) and the open group (patients who underwent open gastrectomy). To correct different demographic and clinical factors in the two groups, a propensity score matching was used at a 1:1 ratio, and, finally, 184 patients were enrolled in this study, 92 patients in each group. Preoperative characteristics, surgical results, and long-term results were analyzed. RESULTS: Preoperative baseline variables were well balanced in both groups. There were no differences of the extent of surgery between the two groups. With the exception of shorter postoperative hospital stay and less blood loss in the laparoscopy group as compared with the open group, there were no significant differences in surgical, pathological, and long-term outcomes. The 5-year overall survival rates were 57% in the laparoscopy group and 50% in the open group (p=0.606). The 5-year disease-free survival rates were 48% in the laparoscopy group and 42% in the open group (p=0.515). CONCLUSION: Laparoscopic gastrectomy for locally advanced gastric carcinoma is safe, and long-term outcomes were comparable to those who underwent open resection.


Assuntos
Gastrectomia/métodos , Laparoscopia/métodos , Pontuação de Propensão , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida
19.
iScience ; 27(3): 109144, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38380259

RESUMO

A micro turbine engine's thrust relies on combustion chamber efficiency, closely tied to the design of its evaporation tube. This study thoroughly investigates evaporation and atomization processes within the tube, introducing a pioneering bionic-inspired structure. Integrating a honeycomb sheet into the traditional tube, both configurations undergo a comparative analysis. Results show a direct correlation between elevated air temperatures and reduced fuel droplet diameters, leading to increased fuel evaporation rates. The bionic tube, with a 1mm-thick honeycomb sheet, 0.6 mm aperture diameter, and 3 sheets, significantly improves fuel droplet atomization and evaporation compared to the conventional design. This research holds broader significance in understanding and enhancing micro turbine engine performance.

20.
PeerJ Comput Sci ; 10: e1760, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38259885

RESUMO

Background: Improvement on the updating equation of an algorithm is among the most improving techniques. Due to the lack of search ability, high computational complexity and poor operability of equilibrium optimizer (EO) in solving complex optimization problems, an improved EO is proposed in this article, namely the multi-strategy on updating synthetized EO (MS-EO). Method: Firstly, a simplified updating strategy is adopted in EO to improve operability and reduce computational complexity. Secondly, an information sharing strategy updates the concentrations in the early iterative stage using a dynamic tuning strategy in the simplified EO to form a simplified sharing EO (SS-EO) and enhance the exploration ability. Thirdly, a migration strategy and a golden section strategy are used for a golden particle updating to construct a Golden SS-EO (GS-EO) and improve the search ability. Finally, an elite learning strategy is implemented for the worst particle updating in the late stage to form MS-EO and strengthen the exploitation ability. The strategies are embedded into EO to balance between exploration and exploitation by giving full play to their respective advantages. Result and Finding: Experimental results on the complex functions from CEC2013 and CEC2017 test sets demonstrate that MS-EO outperforms EO and quite a few state-of-the-art algorithms in search ability, running speed and operability. The experimental results of feature selection on several datasets show that MS-EO also provides more advantages.

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