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1.
Opt Lett ; 49(18): 5256-5259, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39270279

RESUMO

We propose a compact and broadband polarization beam splitter (PBS) based on a thin-film lithium niobate. The hybrid plasmonic waveguide (HPW) is used as a bridge in a three-waveguide coupler to achieve large birefringence. A degree of phase-matching is introduced for optimization. The proposed PBS exhibits a 125-nm bandwidth (1495-1620 nm) of polarization extinction ratio (PER) over 20 dB or an 85-nm bandwidth (1515-1600 nm) of PER over 25 dB, with a device length of only 81 µm. An ultra-low insertion loss of 0.04 dB is achieved around the wavelength of 1550 nm. In addition, the proposed device exhibits high robustness of the fabrication tolerance.

2.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(6): 579-586, 2023 Jun 15.
Artigo em Zh | MEDLINE | ID: mdl-37382126

RESUMO

OBJECTIVES: To study the role and mechanism of platelet-derived growth factor BB (PDGF-BB) on platelet production in Kawasaki disease (KD) mice and human megakaryocytic Dami cells through in vitro and invivo experiments. METHODS: ELISA was used to measure the expression of PDGF in the serum of 40 children with KD and 40 healthy children. C57BL/6 mice were used to establish a model of KD and were then randomly divided into a normal group, a KD group, and an imatinib group (30 mice in each group). Routine blood test was performed for each group, and the expression of PDGF-BB, megakaryocyte colony forming unit (CFU-MK), and the megakaryocyte marker CD41 were measured. CCK-8, flow cytometry, quantitative real-time PCR, and Western blot were used to analyze the role and mechanism of PDGF-BB in platelet production in Dami cells. RESULTS: PDGF-BB was highly expressed in the serum of KD children (P<0.001). The KD group had a higher expression level of PDGF-BB in serum (P<0.05) and significant increases in the expression of CFU-MK and CD41 (P<0.001), and the imatinib group had significant reductions in the expression of CFU-MK and CD41 (P<0.001). In vitro experiments showed that PDGF-BB promoted Dami cell proliferation, platelet production, mRNA expression of PDGFR-ß, and protein expression of p-Akt (P<0.05). Compared with the PDGF-BB group, the combination group (PDGF-BB 25 ng/mL + imatinib 20 µmol/L) had significantly lower levels of platelet production, mRNA expression of PDGFR-ß, and protein expression of p-Akt (P<0.05). CONCLUSIONS: PDGF-BB may promote megakaryocyte proliferation, differentiation, and platelet production by binding to PDGFR-ß and activating the PI3K/Akt pathway, and the PDGFR-ß inhibitor imatinib can reduce platelet production, which provides a new strategy for the treatment of thrombocytosis in KD.


Assuntos
Síndrome de Linfonodos Mucocutâneos , Trombocitose , Criança , Humanos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Becaplermina , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Trombocitose/tratamento farmacológico , Trombocitose/etiologia , RNA Mensageiro
3.
Sensors (Basel) ; 22(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36081082

RESUMO

Recent work on intelligent agents is a popular topic among the artificial intelligence community and robotic system design. The complexity of designing a framework as a guide for intelligent agents in an unknown built environment suggests a pressing need for the development of autonomous agents. However, most of the existing intelligent mobile agent design focus on the achievement of agent's specific practicality and ignore the systematic integration. Furthermore, there are only few studies focus on how the agent can utilize the information collected in unknown build environment to produce a learning pipeline for fundamental task prototype. The hierarchical framework is a combination of different individual modules that support a type of functionality by applying algorithms and each module is sequentially connected as a prerequisite for the next module. The proposed framework proved the effectiveness of ESNI system integration in the experiment section by evaluating the results in the testing environment. By a series of comparative simulations, the agent can quickly build the knowledge representation of the unknown environment, plan the actions accordingly, and perform some basic tasks sequentially. In addition, we discussed some common failures and limitations of the proposed framework.


Assuntos
Algoritmos , Inteligência Artificial , Ambiente Construído , Aprendizagem
4.
Molecules ; 27(11)2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35684562

RESUMO

Very volatile organic compounds (VVOCs) are a group of important odor pollutants affecting indoor air quality that have been shown to be harmful to human health. A 15 L environmental chamber, combined with multi-bed tube was used to collect gases. Fifteen very volatile organic compounds (VVOCs), including 12 odor compounds, were identified from veneered medium density fiberboard coated with water-based lacquer (WB-MDF) using gas chromatography-mass spectrometry/olfactometry (GC-MS/O). The total very volatile organic compound (TVVOC) and total odor intensity (TOI) showed a decreasing trend over time, reaching equilibrium on day 28. TVVOC showed an overall slow-fast-slow emission profile, from day 3 to day 7, with a maximum decay rate of 29.7%. TOI showed the greatest rate of decline from day 1 to day 3, at approximately 12%. Alkane and alcohol VVOCs were the more abundant compounds, accounting for at least 60% and even up to 80% of the total. The major odor impression was fruity, with a highest odor rating of 6.6, followed by sweet, with an odor rating of 6.1. Although the odor impression changed from sweet to fruity over time, it seemed pleasant overall. The odor contributors were mainly alkanes, alcohols, esters, and ethers, which had relatively high odor intensities. The main odor-contributing substances were dichloromethane, ethanol, ethyl acetate, 2-methylacrylic acid methyl ester, and tetrahydrofuran. When WB-MDF is used for furniture or other decorative materials, it is strongly recommended that it be stored under ventilation for at least 28 days and the adoption of substitute solvents of lacquers, modified adhesives, and low-odor wood raw materials is recommended. These possible initiatives would contribute to the aim of building an environmentally friendly indoor environment.


Assuntos
Compostos Orgânicos Voláteis , Humanos , Laca , Odorantes , Olfatometria , Água
5.
PLoS One ; 19(4): e0297986, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38630668

RESUMO

In recent years, virtual reality (VR) technology has emerged as a powerful tool in the field of therapeutic landscapes. For hospitalized patients or individuals with limited mobility, VR provides highly personalized therapy by simulating authentic natural environments within a safe, convenient, and engaging setting. This study investigated the effectiveness of immersing patients in virtual natural environments for health recovery and compared the varying impacts of different types of landscapes on patients' recovery levels. The aim was to complement traditional medical approaches and enhance environmental design in the field of public health. Researchers systematically reviewed databases (January 2018 to August 2, 2023) to identify randomized controlled trials comparing the efficacy of virtual nature immersion with other treatments. The inclusion/exclusion criteria were established based on the population, intervention, comparison, outcomes, study design, and other aspects (expanded PICO) framework. The Cochrane tool was employed to assess the risk of bias. Meta-analysis was conducted by pooling the mean differences with a 95% confidence interval. Among 30 trials, a total of 2123 patients met the inclusion criteria, with 15 studies included in the meta-analysis. 30 trials met the criteria. Results show significant improvements in pain, anxiety, fear, and some physiological indicators with virtual nature-based treatments. On the other hand, natural scenes incorporating blue and green elements have been applied more extensively and have shown more significant effects. In comparison to conventional methods, this study strongly advocates that virtual reality environments are a crucial tool in bridging the gap between patients and nature, demonstrating their potential to reshape medical interventions and improve environmental design in the field of public health.


Assuntos
Saúde Pública , Ensaios Clínicos Controlados Aleatórios como Assunto , Realidade Virtual , Humanos , Planejamento Ambiental , Terapia de Exposição à Realidade Virtual/métodos
6.
Sci Total Environ ; 883: 163635, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37100146

RESUMO

Compared to traditional mechanical brownfield remediation strategies, phytoremediation as a sustainable and low-impact solution, yielding long-term soil chemical improvement. As a common part of many local plant communities, spontaneous invasive plants have advantages over native species in growth speed and resource-use efficiency and are many are effective on degrading or removing chemical soil pollutants. This research presents a methodology for using spontaneous invasive plants as the agent of phytoremediation for brownfield remediation is an innovative component of ecological restoration and design. This research explores s conceptual and applicable model of using spontaneous invasive plants in the phytoremediation of brownfield soil for environmental design practice. This research summarizes five parameters (Soil Drought Level, Soil Salinity, Soil Nutrients, Soil Metal Pollution, and Soil pH) and their classification standards. Based on the five parameters, a series of experiments were designed to examine 5 spontaneous invasive species' tolerance and performance to different soil conditions. Taking the research results as a data base, this research developed a conceptual model of selecting suitable spontaneous invasive plants for brownfield phytoremediation by overlaying the soil condition data and plants' tolerance data. Using a brownfield site in Boston metropolitan region as a case study, the research tested the feasibility and rationality of this model. The results propose a novel approach and materials for general environmental remediation of contaminated soil by involving spontaneous invasive plants. It also transforms the abstract phytoremediation knowledge and data to an applicable model which integrates and visualizes the requirements of scientific plant selection, design aesthetic, and ecosystem factors to help the environmental design process in brownfield remediation.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Biodegradação Ambiental , Ecossistema , Solo , Metais , Poluentes do Solo/análise , Plantas
7.
Inflammation ; 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37948033

RESUMO

Vascular endothelial inflammation and endothelial dysfunction are the main causes of endothelial injury in Kawasaki disease (KD). Human umbilical cord-derived mesenchymal stem cells (Huc-MSCs) have multiple functions in immune regulation. This study examined whether Huc-MSCs inhibited endothelial inflammation and improved endothelial function in KD through constructing cell and in vivo animal KD vasculitis models. The pyroptosis factor NOD-like receptor protein 3 (NLRP3) was involved in the inflammatory process in the acute phase of KD. After tail vein injection of Huc-MSCs, inflammatory cell infiltration and the expression of pyroptosis-related proteins in the LCWE-induced KD mouse vasculitis model were significantly reduced. In vitro, NLRP3-dependent pyroptosis successfully induced human umbilical vein endothelial cell (HUVEC) damage. Huc-MSCs effectively increased the abilities of impaired HUVECs to proliferate, migrate, invade, and form vessel-like tubes, while inhibiting their apoptosis, suggesting that Huc-MSCs can reduce inflammation and improve vascular endothelial function by inhibiting the NLRP3-dependent pyroptosis pathway in KD, providing a possibility and novel target for KD endothelial injury and dysfunction.

8.
Environ Sci Pollut Res Int ; 26(20): 20769-20779, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31104236

RESUMO

This study sought to identify volatile organic compounds (VOCs) and examine the characteristics of odor-active substances from polyvinyl chloride (PVC)-overlaid medium density fiberboard (MDF). A microchamber thermal extractor was used for sampling, gas chromatography-mass spectrometry was used to identify VOCs, and gas chromatography-olfactometry-mass spectrometry was used to analyze odor-active substances from PVC-overlaid MDF over 28 days. The results showed that 38 VOCs were identified from PVC-overlaid MDF, while only 23 odor-active substances were detected by gas chromatography-olfactometry, which indicated that some VOCs did not generate odor. The main VOCs released by PVC-overlaid MDF were aromatic hydrocarbons, ketones, and esters. There was a strong correlation between concentration and odor intensity of the main VOCs. When the total amount of odor-active substances was not significantly different, the overall odor intensity was determined by the intensity of the key odorants. The greater the intensity of the key odorants, the greater the overall odor intensity. There were eight main classes of odors from PVC-overlaid MDF: aromatic, fresh scent, fruity, sour, sweet, grassy, pungent, and special scent. Among them, the main odor characteristics were aromatic, sour, and fresh scent, which were primarily generated by toluene, ethylbenzene, phenanthrene, and dibutyl phthalate.


Assuntos
Odorantes/análise , Cloreto de Polivinila/química , Compostos Orgânicos Voláteis/análise , Materiais de Construção , Cromatografia Gasosa-Espectrometria de Massas , Olfatometria
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