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1.
Accid Anal Prev ; 202: 107600, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38663272

RESUMEN

In China, visual guidance systems are commonly used in tunnels to optimize the visual reference system. However, studies focusing specifically on visual guidance systems in the tunnel entrance zone are limited. Hence, a driving simulation test is performed in this study to quantitatively evaluate the effectiveness of (i) visual guidance devices at different vertical positions (pavement and roadside) and (ii) a multilayer visual guidance system for regulating driving behavior in the tunnel entrance zone. Furthermore, the characteristics of driving behavior and their effects on traffic safety in the tunnel entrance zone are examined. Data such as the vehicle position, area of interest (AOI), throttle position, steering wheel angle, and lane center offset are obtained using a driving simulation platform and an eye-tracking device. As indicators, the first fixation position (FP), starting deceleration position (DP), average throttle position (TPav), number of deceleration stages (N|DS), gradual change degree of the vehicle trajectory (G|VT), and average steering wheel angle (SWAav) are derived. The regulatory effect of visual guidance devices on driving performance is investigated. First, high-position roadside visual guidance devices effectively reduce decision urgency and significantly enhance deceleration and lane-keeping performance. Specifically, the advanced deceleration performance (AD), smooth deceleration performance (SD), trajectory gradualness (TG), and trajectory stability (TS) in the tunnel entrance zone improve by 63%, 225%, 269%, and 244%, respectively. Additionally, the roadside low-position visual guidance devices primarily target the trajectory gradualness (TG), thus resulting in improvements by 80% and 448% in the TG and TS, respectively. Meanwhile, the pavement visual guidance devices focus solely on enhancing the TS and demonstrates a relatively lower improvement rate of 99%. Finally, the synergistic effect of these visual guidance devices facilitates the multilayer visual guidance system in enhancing the deceleration and lane-keeping performance. This aids drivers in early detection and deceleration at the tunnel entrance zone, reduces the urgency of deceleration decisions, promotes smoother deceleration, and improves the gradualness and stability of trajectories.


Asunto(s)
Conducción de Automóvil , Desaceleración , Humanos , China , Simulación por Computador , Accidentes de Tránsito/prevención & control , Adulto , Masculino , Tecnología de Seguimiento Ocular , Femenino , Seguridad , Adulto Joven , Planificación Ambiental
2.
Clin Transl Med ; 13(8): e1346, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37525587

RESUMEN

BACKGROUND: Breast cancer (BC) is a highly heterogeneous disease, and although immunotherapy has recently increased patient survival in a number of solid and hematologic malignancies, most BC subtypes respond poorly to immune checkpoint blockade therapy (ICB). B cells, particularly those that congregate in tertiary lymphoid structures (TLS), play a significant role in antitumour immunity. However, B-cell heterogeneity at single-cell resolution and its clinical significance with TLS in BC need to be explored further. METHODS: Primary tumour lesions and surrounding normal tissues were taken from 14 BC patients, totaling 124,587 cells, for single-cell transcriptome sequencing and bioinformatics analysis. RESULTS: Based on the usual markers, the single-cell transcriptome profiles were classified into various clusters. A thorough single-cell study was conducted with a focus on tumour-infiltrating B cells (TIL-B) and tumour-associated neutrophils (TAN). TIL-B was divided into five clusters, and unusual cell types, such as follicular B cells, which are strongly related to immunotherapy efficacy, were identified. In BC, TAN and TIL-B infiltration are positively correlated, and at the same time, compared with TLS-high, TAN and TIL-B in TLS-low group are significantly positively correlated. CONCLUSIONS: In conclusion, our study highlights the heterogeneity of B cells in BC, explains how B cells and TLS contribute significantly to antitumour immunity at both the single-cell and clinical level, and offers a straightforward marker for TLS called CD23. These results will offer more pertinent information on the applicability and effectiveness of tumour immunotherapy for BC.


Asunto(s)
Neoplasias de la Mama , Estructuras Linfoides Terciarias , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Transcriptoma/genética , Estructuras Linfoides Terciarias/genética , Estructuras Linfoides Terciarias/metabolismo , Terapia Neoadyuvante , Linfocitos Infiltrantes de Tumor , Pronóstico
3.
Opt Express ; 30(14): 25410-25417, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-36237072

RESUMEN

We propose the concept and experimentally verify the operation of terahertz quantum cascade laser sources based on intra-cavity Cherenkov difference-frequency generation on a silicon substrate with the current injection layer configured as a metal wire grid. Such a current injector configuration enables high transmission of TM-polarized terahertz radiation into the silicon substrate while simultaneously providing a low-resistivity metal contact for current injection.

4.
Front Microbiol ; 13: 860123, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35495731

RESUMEN

A linalool/polycaprolactone (LL/PCL) antibacterial film was prepared by using a coaxial electrospinning process, and its physical and chemical properties were characterized. The antibacterial film was formed into an active antibacterial gasket, and its effect on salmon preservation was analyzed. The results show that the LL/PCL nanofiber membrane had a well-developed microstructure, and the fiber surface was smooth and uniform. The diameter of the fibers in the PCL membrane without the core material (linalool) was 113.92 ± 23.74 nm. In contrast, the diameter of the coaxial nanofiber membrane with linalool increased, and the diameter of the LL/PCL membranes with 20% and 40% linalool was 220.62 ± 44.01 and 232.22 ± 56.27 nm, respectively. The hydrophobicity and water vapor permeability were enhanced, whereas the tensile strength and elongation at break decreased slightly, while the thermal stability did not differ significantly with the incorporation of linalool. Analysis of the sustained release of linalool showed that the LL/PCL coaxial fiber membranes could release linalool into the reaction system for a long time. The LL/PCL nanofiber film was used to create an antibacterial active gasket for salmon preservation experiments. Sensory evaluation and analyses of the total bacterial count, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), pH, texture (hardness, elasticity, chewiness, and viscoelasticity), water distribution change, and aroma using an electronic nose were used to determine the quality of salmon. It was found that food-grade tinfoil and the PCL gasket had no significant effect on the freshness of salmon, while the active antibacterial gasket samples containing linalool could decrease the rate of decay salmon and effectively prolong the shelf-life of salmon by releasing linalool.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38751510

RESUMEN

Background: High levels of serum uric acid (SUA) are associated with a poor survival rate of breast cancer. Meanwhile, a sharp increase in SUA after chemotherapy may lead to tumor lysis syndrome (TLS). We created and validated a nomogram to help doctors better manage the patient's SUA level ahead of time in this study. Methods: From July 2012 to June 2021, 206 patients with breast cancer undergoing chemotherapy participated in the study. They are randomly divided into training set (n=137) and validation set (n=69). Univariate and multivariate logistic regression analysis was used to screen the independent predictors of the risk of elevated uric acid in the whole training set data. The receiver operating characteristic (ROC) curve and decision curve assessed the accuracy and clinical application value of nomogram. Results: We confirmed that body mass index (BMI), age, menopause, EC-T chemotherapy (epirubicin-cyclophosphamide followed by paclitaxel) and THP + C-T (pirarubicin-cyclophosphamide followed by paclitaxel) are independent risk factors for high SUA. We established a nomogram for high SUA risk prediction to help clinicians make individualized choice of chemotherapy regimen. In the training cohort, the area under the ROC curve (AUC) showed statistical accuracy (AUC =0.796). Decision curve analysis proved the clinical value of the nomogram. Conclusions: This nomogram can be used to calculate the specific likelihood of high SUA in patients with breast cancer undergoing chemotherapy with different chemotherapy options.

6.
Int J Biol Macromol ; 188: 708-718, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34403673

RESUMEN

Seafood spoilage can be prevented by inhibiting the quorum sensing (QS) system between bacteria. However, membrane materials combining freshness indicators with QS inhibition features have rarely been reported. Therefore, in this study, pH-sensitive polylactic acid-naringin coaxial electrospun fibers capable of maintaining and monitoring freshness were prepared and investigated. Surface analysis revealed that the fiber membranes exhibited a smooth surface and an average diameter of 243 nm. FTIR spectroscopy analysis revealed characteristic absorption peaks at 3265 and 1124 cm-1, confirming the successful loading of naringin and bromocresol purple. Release behavior analysis verified the uninterrupted release of naringin within 192 h, which enabled the fibers to achieve a protease inhibitory activity rate of 35.94%. Furthermore, the coaxial fibers successfully inhibited the expression of rhlI, rhlR, aprA, and fliA in Pseudomonas fluorescens. The real-world applicability of the coaxial fibers was evaluated by the salmon spoilage assay, where a 4-d extension to the shelf life of the coated fillets was attained. Additionally, the color of the coaxial fibers changed with the deterioration of salmon quality and the ΔE value increased from 4.75 to 26.51. These results verify that the prepared fibers can effectively monitor the freshness of seafood products and improve their storage conditions.


Asunto(s)
Flavanonas/química , Embalaje de Alimentos , Membranas Artificiales , Nanofibras/química , Poliésteres/química , Animales , Antibacterianos/farmacología , Rastreo Diferencial de Calorimetría , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Músculos , Pseudomonas fluorescens/efectos de los fármacos , Percepción de Quorum/efectos de los fármacos , Salmón , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
7.
Opt Express ; 27(8): 10449-10455, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-31052904

RESUMEN

An effective method for wavelength tuning in an optical parametric oscillator (OPO) was proposed using noncollinear phase-matching (PM) in a ring cavity. This method was particularly useful for noncritically phase-matched (NCPM) KTP/KTA OPOs where changing the crystal orientation or working temperature is ineffective. A wide tuning range in the eye-safe band from 1572.9 nm to 1684.2 nm was realized pumped by an Nd:YAG laser at 1.06 µm in an NCPM KTP OPO while the internal noncollinear angle was tuned from 0 to 3.1° or the external angle from 0° to 5.8°, with slight variation of the deflection angle of one cavity mirror. The good beam quality and high spectrum intensity of the narrow-linewidth Nd:YAG laser resulted in 33.3% conversion efficiency for the collinear case and above 11% throughout the tuning range. Such OPOs have many potential applications where tunable eye-safe lasers are required, and the proposed wavelength tuning method can be extended to all kinds of OPOs.

8.
Opt Express ; 25(25): 31988-31996, 2017 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-29245866

RESUMEN

A compact and stable terahertz (THz) source is demonstrated based on difference frequency generation (DFG) pumped by an efficient dual-wavelength acousto-optic (AO) Q-switched solid-state Nd:YLF laser with composite gain media (a-cut and c-cut) in the coaxial pumping configuration. Optimal power ratio and pulse synchronization of the orthogonal polarized 1047/1053 nm dual-wavelength laser could be realized by varying the pump focusing depth and/or pump wavelength. The total power of 2.92 W was obtained at 5 kHz pumped by 10-W laser-diode power at 803 nm. Such an efficient dual-wavelength laser demonstrated good stability and inconspicuous timing jitter benefiting from the suppressed gain competition between two resonating wavelengths. An 8-mm-long GaSe crystal was employed to generate THz waves at 1.64 THz by DFG and the maximum THz average output power was about 0.93 µW. This compact coaxial pumping method can be extended to all kinds of neodymium (Nd) doped laser crystals to produce different dual-wavelength lasers for various THz wavelength generation, which have good prospects for portable and costless applications like imaging, non-destructive inspection, etc.

9.
Opt Express ; 24(20): 23368-23375, 2016 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-27828399

RESUMEN

A compact efficient high-repetition-rate doubly-resonant dual-wavelength KTP optical parametric oscillator (OPO), with output power up to 3.65 W and tuning ranges of 2.088-2.133 µm/2.171-2.122 µm for signal/idler waves, was deployed for terahertz (THz) generation in a GaSe crystal. Based on difference frequency generation (DFG), the THz wave was continuously tunable from 730.9 µm (0.41 THz) to 80.8 µm (3.71 THz), believed to be the first report of a compact high-repetition-rate widely-tunable THz source. The maximum THz average power reached 1.2 µW at 1.54 THz and the corresponding DFG efficiency was 7.8 × 10-7, entirely suitable for portable applications. The utility of the THz source was also demonstrated through spectroscopy and imaging experiments.

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