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1.
Materials (Basel) ; 17(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38255543

RESUMO

Freezing conditions under different humidity will influence the mechanical properties of geotextiles, leading to the gradual fracture of geotextiles. It brings hidden danger to the whole isolation, reinforcement and protection of rock and soil. It is particularly important to study the tensile and puncture properties of geotextiles considering low temperature and moisture content. In this paper, a series of tensile and puncture tests of geotextiles are performed under different low temperatures (0, -3, -6, -9, and -12 °C) and at different moisture content levels (0, 5, 10, 30, 50, and 80%). From the microscopic perspective, the failure mechanism considering the low temperature and moisture content was explained comprehensively. Experimental results indicate that with a decrease in freezing temperature, the tensile strength of geotextiles increases as a parabolic function while the elongation at failure decreases as an exponential function. Additionally, the puncture strength of geotextiles presented a parabolic increase with the decreasing temperature. Under the freezing temperature environment, the higher moisture content of geotextiles can generate a higher puncture strength increment. This research contributes to a more comprehensive understanding of the tensile and puncture properties of geotextile materials considering low temperature and moisture content. It can provide important guidance for the design of slopes, the reinforcement of earthen dams, and roadbed reinforcement with geotextiles in cold regions.

2.
Front Public Health ; 11: 1241029, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38152666

RESUMO

The outbreak of novel coronavirus pneumonia (COVID-19) is closely related to the intra-urban environment. It is important to understand the influence mechanism and risk characteristics of urban environment on infectious diseases from the perspective of urban environment composition. In this study, we used python to collect Sina Weibo help data as well as urban multivariate big data, and The random forest model was used to measure the contribution of each influential factor within to the COVID-19 outbreak. A comprehensive risk evaluation system from the perspective of urban environment was constructed, and the entropy weighting method was used to produce the weights of various types of risks, generate the specific values of the four types of risks, and obtain the four levels of comprehensive risk zones through the K-MEANS clustering of Wuhan's central urban area for zoning planning. Based on the results, we found: ①the five most significant indicators contributing to the risk of the Wuhan COVID-19 outbreak were Road Network Density, Shopping Mall Density, Public Transport Density, Educational Facility Density, Bank Density. Floor Area Ration, Poi Functional Mix ②After streamlining five indicators such as Proportion of Aged Population, Tertiary Hospital Density, Open Space Density, Night-time Light Intensity, Number of Beds Available in Designated Hospitals, the prediction accuracy of the random forest model was the highest. ③The spatial characteristics of the four categories of new crown epidemic risk, namely transmission risk, exposure risk, susceptibility risk and Risk of Scarcity of Medical Resources, were highly differentiated, and a four-level integrated risk zone was obtained by K-MEANS clustering. Its distribution pattern was in the form of "multicenter-periphery" gradient diffusion. For the risk composition of the four-level comprehensive zones combined with the internal characteristics of the urban environment in specific zones to develop differentiated control strategies. Targeted policies were then devised for each partition, offering a practical advantage over singular COVID-19 impact factor analyses. This methodology, beneficial for future public health crises, enables the swift identification of unique risk profiles in different partitions, streamlining the formulation of precise policies. The overarching goal is to maintain regular social development, harmonizing preventive measures and economic efforts.


Assuntos
COVID-19 , Epidemias , Humanos , Idoso , COVID-19/epidemiologia , Cidades , SARS-CoV-2 , Surtos de Doenças
3.
Sci Rep ; 13(1): 13967, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37634016

RESUMO

Improper layout of drainage structures and inadequate insulation measures in cold tunnels can result in varying degrees of frost formation during operation. This study focuses on the Hongtoushan highway tunnel as an example, where the distribution characteristics of the temperature field around the lower drainage structure under different arrangements are investigated through indoor model testing. The results indicate that there is a significant hysteresis phenomenon in temperature changes across the cross-section as the burial depth increases. With an increase in the burial depth of the surrounding rock, the hysteresis time of temperature changes gradually elongates. The temperature variation pattern can be approximated by a cubic polynomial. In the vertical section, as the tunnel depth increases, the temperature of the surrounding rock in the lower part of the tunnel gradually rises while the amplitude of temperature change diminishes. The temperature near the centerline is relatively lower compared to the sides, where the temperature gradually increases moving away from the centerline.

4.
Dalton Trans ; 52(11): 3300-3307, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36847192

RESUMO

Detection of Fe(III) and Cu(II) in water is highly desirable because their abnormal levels can cause serious harm to human health and environmental safety. In this work, a ratiometric luminescence sensing platform based on lanthanide-based silica nanoparticles was constructed for the detection of Fe3+ and Cu2+ ions. The terbium-silica nanoparticles (named SiO2@Tb) with dual-emission signals were successfully prepared by grafting Tb3+ ions onto trimellitic anhydride (TMA) functionalized silica nanospheres. It can serve as a ratiometric fluorescent probe for the detection of Fe3+ and Cu2+ ions in water with the green emission of Tb3+ ions as a response signal and the blue emission of silica nanospheres as the reference signal. Significantly, an easy-to-differentiate color change for visual detection was also realized. SiO2@Tb shows high sensitivity even in very low concentration regions towards the sensing of Fe3+ and Cu2+ with low detection limits of 0.75 µM and 0.91 µM, respectively. Moreover, the mechanism for the luminescence quenching of SiO2@Tb was systematically investigated, and was attributed to the synergetic effect of the absorption competition quenching (ACQ) mechanism and cation exchange. This study demonstrates that SiO2@Tb can be employed as a promising fluorescent probe for the detection of Fe3+ and Cu2+ ions, and the combination of lanthanide ions with silica nanoparticles is an effective strategy to construct a ratiometric fluorescent sensing platform for the determination of analytes in environmental detection.

5.
J Cosmet Dermatol ; 22(2): 497-504, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36217740

RESUMO

BACKGROUND: Atrophic acne scars (AAS) impact the aesthetic appearance, inducing social and psychological problems. Effective and safe therapy for AAS is urgently needed now. Microneedling fractional radiofrequency (MFRF) has emerged as a minimal invasive alteration for treating AAS lately, while the existing data on Chinese population was few. AIMS: We aimed to explore the effectivity and safety of MFRF in Chinese patients with facial AAS and analyze the response of different subtypes to MFRF treatment. METHODS: We conducted a retrospective analysis using data from medical records and clinical photographs of 40 Chinese patients with AAS with Fitzpatrick skin type III-IV, all of them had received 3 MFRF treatments with 1-month intervals and were followed up 3 months after the last treatment. The clinical severity was assessed through échelle d'évaluation clinique des cicatrices d'acné (ECCA) score at each visit. Clinical photographs were taken by VISIA. Patients were asked to evaluate their satisfaction of the treatment using a 5-point Likert scale at the last visit. RESULTS: ECCA score decreased more than a half at the last visit based on the baseline. Among the three types of AAS, the M-shaped scars respond most quickly to MFRF and the U-shaped scars improved the most after 3 months follow-up. A significant improvement was seen in clinical appearance, parallel to the change of ECCA, indicating the remarkable improvement of AAS after the MFRF treatment. Concomitant active acne was controlled along with the improvement of AAS. Statistics from VISIA showed excellent improvement in pores and texture as well. Side effects including pain and erythema were transient and mild. The number of MFRF treatment sessions was positively associated with the degree of improvement. Of the total 39 patients who had given a score of satisfaction, more than 89% (35 patients) were very satisfied or satisfied with the outcome. CONCLUSIONS: To sum up, our study reveals that MFRF provides high efficiency in treating Chinese AAS patients with high satisfaction and low risk of adverse effects. M-shaped scars are the most sensitive type to the treatment, but the U-shaped scars improve most at the last visit. The simultaneous minimization of pores and improvement of skin texture imply the increased collagen stimulated by MFRF. Regular MFRF should be considered a good choice in treating AAS.


Assuntos
Acne Vulgar , Cicatriz , Humanos , Cicatriz/etiologia , Cicatriz/terapia , Estudos Retrospectivos , População do Leste Asiático , Dor , Acne Vulgar/complicações , Acne Vulgar/terapia , Atrofia/complicações , Resultado do Tratamento
6.
Environ Sci Pollut Res Int ; 30(3): 7402-7414, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36040691

RESUMO

Through field surveys, sampling, and laboratory experiments, the content, enrichment, and migration characteristics of heavy metals in the rock-soil-tea system in the Guizhou metamorphic rock area were analyzed herein. The results show that the As and Hg contents in metamorphic sandstone in the study area are higher than those in slate, while the Mn, Zn, Pb, and Ni contents in slate are higher. The content of heavy metals in the sandstone of the Jialu formation of the Xiajiang group in Neoproterozoic is the highest, and that of the slate of the Fanzhao formation is the lowest. The content of As in the rock samples in the study area is higher than that in the Epicontinental crust, while Cd is found to be deficient. The heavy metals at some soil points exceed the standard, but this does not affect the growth and development of tea. The content of heavy metals in most tea is lower than the safety limit standards, and the THQ value is less than 1, indicating that the heavy metals in tea in Guizhou metamorphic rock areas pose no concern for human health. In the metamorphic rock distribution areas of Guizhou, tea does not enrich As, Cr, Hg, and Pb in soil, but enriches Mn, Cu, Ni, and Zn to varying degrees, with the enrichment of Mn being the strongest.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Humanos , Solo/química , Chumbo , Poluentes do Solo/análise , Monitoramento Ambiental , Medição de Risco , Metais Pesados/análise , China , Chá/química
7.
Am J Transl Res ; 13(10): 12094-12106, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34786147

RESUMO

We injected mouse zygotes with combinations of Cas9 protein, Cas9 mRNA, and two gRNAs targeting a single exon of type I interferon receptor (IFNAR1) to determine the gene targeting efficiencies. Cas9 protein produced on-target mutations more efficiently than Cas9 mRNA when each was used with a single gRNA, regardless of which gRNA was used. When Cas9 mRNA and Cas9 protein were co-injected, the on-target efficiency could reach 97.0% when both gRNAs were used, which was higher than when either gRNA was used alone (61.3% and 75.5%, respectively; P<0.05). Co-injection of Cas9 protein with both gRNAs produced the highest on-target mutation rate of any combination (100.0%). Most on-target mutations were deletions of 2 to 113 nucleotides, and there were few off-target mutations in mutant animals. The expression intensity of IFNAR1 was reduced in heterozygous IFNAR1 +/- mice (IF) and almost or completely absent in homozygous null IFNAR -/- mice compared with that in wild-type mice (IF and Western blot). When both gRNAs targeting IFNAR1 were used simultaneously with two gRNAs targeting FVII, the on-target editing efficiency on each gene was 96.8% and 85.5%, respectively. Co-injection of dual gRNAs and Cas9 protein is an efficient approach for IFNAR1 knockout and multi-gene editing in mice and may be applied in other animal models and breeding livestock.

8.
Dalton Trans ; 50(43): 15593-15601, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34668507

RESUMO

A luminescence sensor based on an europium(III)-based lanthanide-organic framework, [Eu(BCB)(DMF)]·(DMF)1.5(H2O)2 (1), was synthesized via a solvothermal method using 4,4',4''-benzenetricarbonyltribenzoic acid (H3BCB) as a bridging ligand. Single-crystal X-ray diffraction indicates that Eu centers are eight-coordinated with a trigonal dodecahedron and a square antiprismatic configuration, and adjacent Eu atoms are bridged by BCB organic linkers to form a 3D rod-packing structure. Photoluminescence studies show that compound 1 emits bright red luminescence and behaves as a multi-responsive luminescent sensor toward 4-nitrophenol (4-NP) and I- and Fe3+ ions in water with high sensitivity, selectivity and low detection limits. Furthermore, the possible luminescence sensing mechanisms were also investigated by PXRD analysis, UV-vis spectroscopy and X-ray photoelectron spectroscopy (XPS). The recognition mechanism for 4-NP and I- ions can be attributed to the competition absorption and that for Fe3+ ions is considered to be a multi-quenching mechanism dominated by competition absorption. This study demonstrates that the lanthanide-based MOF might be a promising candidate for the detection of 4-NP and I- and Fe3+ ions in aqueous medium.

9.
Dalton Trans ; 50(5): 1697-1702, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33443519

RESUMO

A potent luminescent sensor for the detection of iodide ions was developed based on a terbium(iii)-based lanthanide-organic framework [Tb(cpia)(H2O)2]n·nH2O (1), which was prepared under hydrothermal conditions using the 5-(4-carboxyphenoxy)isophthalic acid (H3cpia) bridging ligand. Compound 1 exhibits superior luminescence quenching behavior towards I- with high sensitivity and selectivity among various anions and shows real-time response. Moreover, the mechanism of the selective luminescence quenching response for I- can be mainly explained by the absorption competition between 1 and I-. According to this quenching mechanism, we find that compound 1 can also detect Br- by adjusting the excitation wavelength. Significantly, this work could serve as a general guidance for the design and synthesis of pollutant sensors.

10.
J Dermatolog Treat ; 32(3): 334-339, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31416363

RESUMO

BACKGROUND: Becker's Nevus (BN) is a benign hamartoma with an esthetically troublesome condition secondary to hyperpigmentation and hypertrichosis. Many treatment modalities have been utilized with variable outcomes. OBJECTIVES: To evaluate the efficacy and safety of intense pulsed light (IPL) in the treatment of BN. PATIENTS AND METHODS: IPL was used at filter of 590 nm, fluence of 18-22 J/cm2, double-pulse mode (pulse width of 3-10 ms, pulse delay of 20-30 ms) at 3-month intervals. Final evaluations were performed by physician global assessment and patient satisfaction. Side effects were monitored at each treatment session and follow-up visit. RESULTS: Twenty-four patients (9 females, 15 males) with BN (16 hypertrichotic, 8 atrichotic) completed the study. The mean number of treatment sessions was 5 ± 2.17. The improvement in atrichotic BN group (4.87 ± 0.35) was significantly greater than that observed in hypertrichotic BN group (3.63 ± 0.89) (p = .001). Hair density simultaneously decreased with treatment in hypertrichotic BN. The mean satisfaction score was 5.75 ± 2.05 and 8 ± 0.93 in hypertrichotic and atrichotic BN groups respectively (p = .002). No repigmentation was noted during the follow-up period. No permanent side effects were observed. CONCLUSIONS: IPL is an effective and well-tolerated treatment option for patients with hypertrichotic and atrichotic BN.


Assuntos
Nevo/terapia , Fototerapia , Neoplasias Cutâneas/terapia , Adolescente , Adulto , Criança , Edema/etiologia , Feminino , Humanos , Hiperpigmentação/terapia , Hipertricose/terapia , Masculino , Pessoa de Meia-Idade , Fototerapia/efeitos adversos , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
11.
Sensors (Basel) ; 19(5)2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30871089

RESUMO

Aiming at the real-time observation requirements in marine science and ocean engineering, based on underwater acoustic communication and satellite communication technology, a seabed real-time sensing system for in-situ long-term multi-parameter observation applications (SRSS/ILMO) is proposed. It consists of a seabed observation system, a sea surface relay transmission buoy, and a remote monitoring system. The system communication link is implemented by underwater acoustic communication and satellite communication. The seabed observation system adopts the "ARM + FPGA" architecture to meet the low power consumption, scalability, and versatility design requirements. As a long-term unattended system, a two-stage anti-crash mechanism, an automatic system fault isolation design, dual-medium data storage, and improved Modbus protocol are adopted to meet the system reliability requirements. Through the remote monitoring system, users can configure the system working mode, sensor parameters and acquire observation data on demand. The seabed observation system can realize the observation of different fields by carrying different sensors such as those based on marine engineering geology, chemistry, biology, and environment. Carrying resistivity and pore pressure sensors, the SRSS/ILMO powered by seawater batteries was used for a seabed engineering geology observation. The preliminary test results based on harbor environment show the effectiveness of the developed system.

12.
J Opt Soc Am A Opt Image Sci Vis ; 33(5): 997-1003, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-27140900

RESUMO

A guided Bloch surface wave resonance (GBR) configuration is introduced for label-free biosensing. The GBR is realized by coupling the first-order diffraction of a subwavelength grating with the Bloch surface wave at the interface between a 1D photonic crystal slab and bio-solution. In addition to sustaining the Bloch surface mode, the photonic crystal provides the design freedom of simultaneously increasing the quality and decreasing the sideband transmissions of the resonance spectrum. The low sideband and high-quality features along with the large sensitivity rising from the strong overlap between the Bloch surface mode and the bio-solution make the GBR suitable for the design of biosensors. Biosensors with a high figure of merit are realized by the compact configurations.


Assuntos
Técnicas Biossensoriais , Algoritmos , Cristalização , Difusão , Processamento de Imagem Assistida por Computador/métodos , Modelos Estatísticos , Refratometria , Propriedades de Superfície
13.
Arch Virol ; 153(12): 2291-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18998045

RESUMO

The capsid protein of PCV2 was expressed by using a recombinant baculovirus with insect Tn5 cells. A large amount of 28-kDa protein was released into the culture medium and self-assembled into PCV2-like particles (PCV2-LPs) with a buoyant density of 1.365 g/cm(3) and a diameter of 20 nm. PCV2-LPs were efficiently expressed, yielding 1 mg of purified particles per 10(7) Tn5 cells. The PCV2-LPs have antigenicity similar to that of authentic PCV2 particles, allowing us to develop a method for sensitively detecting PCV2-specific IgG antibodies. In addition, the PCV2-LPs appeared to be the most promising PCV2 vaccine candidate, by virtue of their potent immunogenicity.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/biossíntese , Proteínas do Capsídeo/biossíntese , Circovirus/imunologia , Proteínas Recombinantes/biossíntese , Vacinas Virais/biossíntese , Animais , Antígenos Virais/imunologia , Baculoviridae/genética , Proteínas do Capsídeo/imunologia , Linhagem Celular , Circovirus/ultraestrutura , Vetores Genéticos , Microscopia Eletrônica de Transmissão , Síndrome Definhante Multissistêmico de Suínos Desmamados/diagnóstico , Síndrome Definhante Multissistêmico de Suínos Desmamados/prevenção & controle , Proteínas Recombinantes/imunologia , Suínos , Vacinas Virais/imunologia
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