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1.
Opt Express ; 32(3): 3891-3911, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297600

RESUMEN

In pursuit of enhancing the display performance of gamut extension algorithms across diverse image types while minimizing image dependency, this study introduces a dynamic gamut extension algorithm. The algorithm is designed to extend the sRGB source gamut towards the wide gamut of a laser display. To evaluate its effectiveness, psychophysical experiments were conducted using four distinct image categories: complexions, scenery, objects, and color blocks and bars. The performance of the proposed algorithm was benchmarked against four established color gamut mapping algorithms. The comparative analysis revealed that our algorithm excels in handling wide color gamuts, outperforming the alternatives in terms of preference and the preservation of detail richness.

2.
Opt Lett ; 49(3): 674-677, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300087

RESUMEN

We demonstrate that through inserting a short length of highly birefringent small-core photonic crystal fiber (Hi-Bi SC-PCF) into a soliton fiber laser, the nonlinear polarization rotation effect in this laser can be manipulated, leading to continuous tuning of the output pulse parameters. In experiments, we observed that by adjusting the polarization state of light launched into the Hi-Bi SC-PCF and varying the cavity attenuation, the laser spectral width can be continuously tuned from ∼7.1 to ∼1.7 nm, corresponding to a pulse-width-tuning range from ∼350 fs to ∼1.56 ps. During the parameter tuning, the output pulses strictly follow the soliton area theory, giving an almost constant time-bandwidth-product of ∼0.31. This soliton fiber laser, being capable of continuous parameter tuning, could be applied as the seed source in ultrafast laser systems and may find some applications in nonlinear-optics and soliton-dynamics experiments.

3.
Opt Lett ; 49(6): 1611, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489463

RESUMEN

This publisher's note contains a correction to Opt. Lett.49, 674 (2024)10.1364/OL.509981.

4.
Opt Lett ; 49(11): 2982-2985, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824308

RESUMEN

We demonstrate a compact ultrafast fiber laser system that can deliver 1.87 GHz pulse train at 1550 nm with a pulse energy of 52 pJ and an ultrashort pulse duration of 57 fs. While an acousto-optic mode-locking fiber laser was used as the seed light source at GHz rate, a stage of Er-doped fiber amplifier boosted the laser power to ∼320 mW, giving a pulse energy of ∼170 pJ. Then, a pulse compression setup was constructed, providing a high compression ratio of ∼10 with a total efficiency of ∼32%. In the cascaded compression configuration, multiple fiber samples with alternately normal and anomalous dispersion were fused together, providing efficient nonlinear spectral broadening while suppressing excessive pulse broadening over propagation. This GHz-rate ultrafast fiber laser, with compact configuration, broad optical spectrum, and high time-resolving ability could be used as the seed light source for constructing high-rate, high-power ultrafast laser systems and may find a few applications in optical measurements and microwave photonics.

5.
Mikrochim Acta ; 191(4): 204, 2024 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-38492076

RESUMEN

Metal-organic gels (MOGs) are unique supramolecular gels that are convenient to synthesize. In this work, a cathodic electrochemiluminescence (ECL) system based on Ag-MOGs as a luminophore and K2S2O8 as a co-reactor was developed. The ECL spectrum of the Ag-MOGs overlapped significantly with the strong UV-Vis spectrum of the SiO2@PANI@AuNPs, which effectively quenched the ECL luminescence of the Ag-MOGs. Relying on the inner filter effect between Ag-MOGs and SiO2@PANI@AuNPs, a novel ECL-IFE immunosensor was developed for the detection of neuron-specific enolase (NSE). Under optimal conditions, the ECL signal of the immunosensor displayed excellent linearity over the NSE concentration range of 10 fg/mL-100 ng/mL. The limit of detection (LOD) was 2.6 fg/mL (S/N = 3) with a correlation coefficient R2 of 0.9975. The ECL immunosensor also exhibited excellent stability and reproducibility for the detection of NSE. The results reported provide a feasible concept for the development analytical methods for the detection of other clinically relevant biomarkers.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Oro , Dióxido de Silicio , Mediciones Luminiscentes/métodos , Inmunoensayo/métodos , Técnicas Biosensibles/métodos , Reproducibilidad de los Resultados , Técnicas Electroquímicas/métodos , Geles , Fosfopiruvato Hidratasa
6.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38338942

RESUMEN

Zoysia japonica (Zoysia japonica Steud.) is a kind of warm-season turfgrass with many excellent characteristics. However, the shorter green period and longer dormancy caused by cold stress in late autumn and winter are the most limiting factors affecting its application. A previous transcriptome analysis revealed that ethephon regulated genes in chlorophyll metabolism in Zoysia japonica under cold stress. Further experimental data are necessary to understand the effect and underlying mechanism of ethephon in regulating the cold tolerance of Zoysia japonica. The aim of this study was to evaluate the effects of ethephon by measuring the enzyme activity, intermediates content, and gene expression related to ethylene biosynthesis, signaling, and chlorophyll metabolism. In addition, the ethylene production rate, chlorophyll content, and chlorophyll a/b ratio were analyzed. The results showed that ethephon application in a proper concentration inhibited endogenous ethylene biosynthesis, but eventually promoted the ethylene production rate due to its ethylene-releasing nature. Ethephon could promote chlorophyll content and improve plant growth in Zoysia japonica under cold-stressed conditions. In conclusion, ethephon plays a positive role in releasing ethylene and maintaining the chlorophyll content in Zoysia japonica both under non-stressed and cold-stressed conditions.


Asunto(s)
Etilenos , Compuestos Organofosforados , Poaceae , Clorofila A/metabolismo , Poaceae/genética , Etilenos/metabolismo , Clorofila/metabolismo
7.
Angew Chem Int Ed Engl ; 63(24): e202404505, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38598471

RESUMEN

Ammonia borane (AB) with 19.6 wt % H2 content is widely considered a safe and efficient medium for H2 storage and release. Co-based nanocatalysts present strong contenders for replacing precious metal-based catalysts in AB hydrolysis due to their high activity and cost-effectiveness. However, precisely adjusting the active centers and surface properties of Co-based nanomaterials to enhance their activity, as well as suppressing the migration and loss of metal atoms to improve their stability, presents many challenges. In this study, mesoporous-silica-confined bimetallic Co-Cu nanoparticles embedded in nitrogen-doped carbon (CoxCu1-x@NC@mSiO2) were synthesized using a facile mSiO2-confined thermal pyrolysis strategy. The obtained product, an optimized Co0.8Cu0.2@NC@mSiO2 catalyst, exhibits enhanced performance with a turnover frequency of 240.9 molH2 ⋅ molmetal ⋅ min-1 for AB hydrolysis at 298 K, surpassing most noble-metal-free catalysts. Moreover, Co0.8Cu0.2@NC@mSiO2 demonstrates magnetic recyclability and extraordinary stability, with a negligible decline of only 0.8 % over 30 cycles of use. This enhanced performance was attributed to the synergistic effect between Co and Cu, as well as silica confinement. This work proposes a promising method for constructing noble-metal-free catalysts for AB hydrolysis.

8.
Opt Express ; 31(16): 26815-26830, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37710532

RESUMEN

The color gamut volume (CGV) and light efficiency of a four-primary display system were theoretically simulated with different wavelength configuration. Given the wavelengths of the blue and red primaries, we optimized the other two primary colors; the wavelength set with the largest CGV was chosen. The maximum CGV, 2.346 × 106, was obtained at (660, 530, 507, 465) nm. The maximum light efficiency was also determined. A trade-off between CGV and light efficiency should be made according to the requirement of the devices. This study provides guidance for the construction of a four-primary laser display system and the optimization of the CGV in multi-primary display systems.

9.
Opt Express ; 31(18): 29843-29858, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37710775

RESUMEN

Holographic optical elements (HOEs) play an important role in augmented reality (AR) systems. However, the fabrication of full-color HOEs is difficult and the diffraction efficiency is low. In this paper, we use the time-scheduled iterative exposure method to fabricate full-color HOEs with high diffraction efficiency. Through this method, a full-color HOE with an average diffraction efficiency of 73.4% was implemented in a single photopolymer, the highest rate yet reported. In addition, the AR system is simulated by the geometric optics method combining k-vector circle and ray tracing and structured by combining laser micro-drop and high diffraction efficiency HOEs. A good color blending effect was achieved in a full-color AR system by using the reconstruction wavelength consistent with the recording light. It can present clear holographic images in a full-color AR display system.

10.
Vet Res ; 54(1): 119, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38093398

RESUMEN

Clinical avian coccidiosis is typically caused by coinfection with several Eimeria species. Recombinant protein and DNA vaccines have shown promise in controlling coccidiosis. On this basis, DNA vaccines that encode multiple epitopes from different Eimeria species may provide broad protection against coinfections. In this study, we designed a fusion gene fragment, 14EGT, that contained concentrated T-cell epitopes from four common antigens of Eimeria species (14-3-3, elongation factor 2, glyceraldehyde-3-phosphate dehydrogenase, and transhydrogenase). The multiepitope DNA vaccine pVAX1-14EGT and recombinant protein vaccine pET-32a-14EGT (r14EGT) were then created based on the 14EGT fragment. Subsequently, cellular and humoral immune responses were measured in vaccinated chickens. Vaccination-challenge trials were also conducted, where the birds were vaccinated with the 14EGT preparations and later exposed to single or multiple Eimeria species to evaluate the protective efficacy of the vaccines. According to the results, vaccination with 14EGT preparations effectively increased the proportions of CD4+ and CD8+ T cells and the levels of Th1 and Th2 hallmark cytokines. The levels of serum IgG antibodies were also significantly increased. Animal vaccination trials revealed alleviated enteric lesions, weight loss, and oocyst output compared to those of the control groups. The preparations were found to be moderately effective against single Eimeria species, with the anticoccidial index (ACI) ranging from 160 to 180. However, after challenge with multiple Eimeria species, the protection provided by the 14EGT preparations was not satisfactory, with ACI values of 142.18 and 146.41. Collectively, the results suggest that a multiepitope vaccine that encodes the T-cell epitopes of common antigens derived from Eimeria parasites could be a potential and effective strategy to control avian coccidiosis.


Asunto(s)
Coccidiosis , Eimeria tenella , Eimeria , Enfermedades de las Aves de Corral , Vacunas Antiprotozoos , Vacunas de ADN , Animales , Eimeria/genética , Pollos , Epítopos de Linfocito T , Linfocitos T CD8-positivos , Antígenos de Protozoos/genética , Coccidiosis/prevención & control , Coccidiosis/veterinaria , Proteínas Recombinantes , Eimeria tenella/genética
11.
Vet Res ; 54(1): 80, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37740213

RESUMEN

Th9 cells play a crucial role in parasite immunity. The development of Th9 cells is facilitated by several cytokines. Key transcription factors, such as STAT6, STAT5, and PU.1, are known to enhance IL-9 expression during the Th9 immune response. NF-κB-mediated transduction pathways participate in the induction of IL-9. In a previous study, we unveiled a unique ribosomal protein derived from Haemonchus contortus excretory-secretory proteins (HcESPs) that interact with host Th9 cells. In the present study, the effects of the Haemonchus contortus ribosomal protein L6 domain DE-containing protein (HcL6) on IL-9 secretion, Th9 differentiation, and IL-9 transcription were assessed by employing ELISA, flow cytometry, and qPCR methodologies. The observations revealed the transcriptional upregulation of several key genes within the Th9 immune response pathway. Moreover, silencing STAT6, PU.1, and NF-κB was found to attenuate the Th9 immune response. In this study, we unveiled the Th9 immune response-inducing capabilities of HcL6 and elucidated some of its underlying mechanisms. These findings suggest that HcL6 is an immunostimulatory antigen capable of inducing the Th9 immune response. These insights could prove instrumental in identifying potential candidate antigens for the development of immunoprophylactic strategies against H. contortus infections.


Asunto(s)
Haemonchus , FN-kappa B , Animales , Cabras , Interleucina-9/genética , Inmunidad
12.
Appl Opt ; 62(5): 1364-1368, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36821240

RESUMEN

Distributed feedback quantum cascade lasers lased at 3.0 THz were prepared and their output performance was analyzed. The optimized grating parameters were obtained by theoretical analyses. Single-mode emission was obtained and a maximum output power of more than 166 mW at 15 K was achieved. The corresponding threshold current density was 257A/c m 2, and the side-mode suppression ratio was more than 15 dB. By changing the input voltage, the frequency was stable with a variation of less than 3 GHz. A beam with obviously fast and slow axis features was observed. Further improvement and the potential application of distributed feedback quantum cascade lasers are discussed.

13.
Appl Opt ; 62(15): 4102-4109, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37706723

RESUMEN

This study explores the application of optical fiber lasers in display systems by integrating a P r3+-doped green all-fiber laser into a laser projection display system. As a control group to compare the results, a 520 nm semiconductor green laser diode module was integrated, similar to the experimental group. The color gamut and speckle performances were studied and compared. The results showed that the experimental group performed slightly better in the color gamut volume. The speckle contrast decreased rapidly in the experimental group when power increased. To our knowledge, this is the first study to apply a fiber laser to a laser display system. The results shed light on developing laser display systems with fewer or no speckle reduction elements.

14.
Mikrochim Acta ; 190(6): 223, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37184586

RESUMEN

This study aimed to design a sandwich electrochemiluminescence (ECL) immunosensor with double co-reaction accelerators for sensitively detecting squamous cell carcinoma antigen (SCCA). First, silver orthophosphate (Ag3PO4) nanoparticles were modified on the surface of EuPO4 nanowires to improve their poor dispersibility/solubility. At the same time, EuPO4 was used as a co-reaction accelerator to catalyze S2O82- to produce more intermediates (SO4•-), significantly enhancing the ECL signal of Ag3PO4. Ag nanoparticles (AgNP) modified on Ag3PO4@EuPO4 composite nanomaterials were used not only as linkers of luminescence groups and biomarkers but also as a co-reaction accelerator to effectively enhance ECL signal. The designed ECL immunosensor displayed several advantages, including good stability and reproducibility. Under the optimal conditions, its linear range in detecting SCCA was 0.0001-50 ng·mL-1, the detection limit was 25 fg·mL-1 (S/N = 3), the recovery was 96.6-100.4%, and the relative standard deviation was less than 4.8%. It was successfully applied to detect SCCA in human serum.


Asunto(s)
Antígenos de Neoplasias , Técnicas Biosensibles , Nanopartículas del Metal , Serpinas , Humanos , Técnicas Electroquímicas , Inmunoensayo , Mediciones Luminiscentes , Reproducibilidad de los Resultados , Plata , Antígenos de Neoplasias/análisis , Serpinas/análisis
15.
Sensors (Basel) ; 23(13)2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37447720

RESUMEN

Composite materials have been widely used in spacecraft structures. Due to the harsh environment in space, gas leakage will occur in the structure, so it is necessary to locate the leakage position in time. In this paper, a beamforming localization method based on a U-shaped sensor array is studied. The array can be divided into two subarrays, which can orientate the direction of leakage sources, respectively. To solve the problem of uneven wave velocity caused by the anisotropy of composite materials, this method modifies the relationship between wave velocity and direction and combines it with the dispersion curve to select a filtering frequency band to reduce the influence of dispersion. The experiment simulates vacuum leakage by pumping holes with a diameter of 3 mm with a vacuum pump. The results show that the U-shaped array beamforming algorithm proposed in this paper can obtain a positioning error of 2.21 cm, which provides a new idea for the structural health detection of spacecraft.

16.
Sensors (Basel) ; 23(6)2023 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-36991763

RESUMEN

Composite materials are widely used, but they are often subjected to impacts from foreign objects, causing structural damage. To ensure the safety of use, it is necessary to locate the impact point. This paper investigates impact sensing and localization technology for composite plates and proposes a method of acoustic source localization for CFRP composite plates based on wave velocity-direction function fitting. This method divides the grid of composite plates, constructs the theoretical time difference matrix of the grid points, and compares it with the actual time difference to form an error matching matrix to localize the impact source. In this paper, finite element simulation combined with a lead-break experiment is used to explore the wave velocity-angle function relationship of Lamb waves in composite materials. The simulation experiment is used to verify the feasibility of the localization method, and the lead-break experimental system is built to locate the actual impact source. The results show that the acoustic emission time-difference approximation method can effectively solve the problem of impact source localization in composite structures, and the average localization error is 1.44 cm and the maximum localization error is 3.35 cm in 49 experimental points with good stability and accuracy.

17.
J Environ Sci Health B ; 58(9): 583-593, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37614009

RESUMEN

In this work, vermicompost was prepared with maize stover and cattle dung in ratios of 60:40 (VC1), 50:50 (VC2) and 40:60 (VC3), and the physicochemical properties of the vermicompost were related to the ratio of the raw materials used. The effect of the vermicomposts on the adsorption kinetics, adsorption isotherms and desorption of atrazine were investigated in unamended soil (S) and soil amended with 4% (w/w) of VC1(S-VC1), VC2(S-VC2) and VC3(S-VC3). The total organic carbon (TOC) content of VC1, VC2 and VC3 was 38.46, 37.33 and 34.47%, the HA content was 43.50, 42.22 and 39.28 g/kg, and the HA/FA ratios was 1.47, 0.44 and 0.83, respectively. The adsorption of atrazine on the soil, on the vermicompost and on soils amended with vermicompost followed a pseudo-second-order kinetic model. The Freundlich equation better fitted the adsorption isotherm of atrazine. The vermicomposts enhanced atrazine adsorption and decreased atrazine desorption. Correlation analysis showed that the TOC and HA were significantly positively correlated with Kf, which indicated that TOC and HA of the vermicomposts contributed significantly to the adsorption and desorption of atrazine. This study demonstrated that vermicomposts have great potential in the bioremediation of atrazine pollution and that their role is related to the raw materials used to prepare them.


Asunto(s)
Atrazina , Animales , Bovinos , Adsorción , Contaminación Ambiental , Heces , Suelo
18.
Angew Chem Int Ed Engl ; 62(40): e202305371, 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37291046

RESUMEN

Ammonia borane (AB) is a promising material for chemical H2 storage owing to its high H2 density (up to 19.6 wt %). However, the development of an efficient catalyst for driving H2 evolution through AB hydrolysis remains challenging. Therefore, a visible-light-driven strategy for generating H2 through AB hydrolysis was implemented in this study using Ni-Pt nanoparticles supported on phosphorus-doped TiO2 (Ni-Pt/P-TiO2 ) as photocatalysts. Through surface engineering, P-TiO2 was prepared by phytic-acid-assisted phosphorization and then employed as an ideal support for immobilizing Ni-Pt nanoparticles via a facile co-reduction strategy. Under visible-light irradiation at 283 K, Ni40 Pt60 /P-TiO2 exhibited improved recyclability and a high turnover frequency of 967.8 mol H 2 ${{_{{\rm H}{_{2}}}}}$ molPt -1 min-1 . Characterization experiments and density functional theory calculations indicated that the enhanced performance of Ni40 Pt60 /P-TiO2 originated from a combination of the Ni-Pt alloying effect, the Mott-Schottky junction at the metal-semiconductor interface, and strong metal-support interactions. These findings not only underscore the benefits of utilizing multipronged effects to construct highly active AB-hydrolyzing catalysts, but also pave a path toward designing high-performance catalysts by surface engineering to modulate the electronic metal-support interactions for other visible-light-induced reactions.

19.
Cancer Sci ; 113(12): 4104-4119, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36047971

RESUMEN

Osteosarcoma is the most prevalent form of primary bone malignancy affecting adolescents. Secretion-associated Ras-related GTPase 1A (SAR1A) is a key regulator of endoplasmic reticulum (ER) homeostasis, but its role as a regulator of osteosarcoma metastasis has yet to be clarified. Bioinformatics analyses revealed SAR1A and RHOA to be upregulated in osteosarcoma patients, with the upregulation of these genes being associated with poor 5-year metastasis-free survival rates. In addition, the upregulation of SAR1A and RHOA in osteosarcoma was highly positively correlated. Immunohistochemical analyses additionally revealed that SAR1A levels were increased in osteosarcoma pulmonary metastases. In vitro wound healing and Transwell assays indicated that knocking down SAR1A or RHOA impaired the invasive and migratory activity of osteosarcoma cells, whereas RHOA overexpression had the opposite effect. Western blotting and immunofluorescent staining revealed the inhibition of osteosarcoma cell epithelial-mesenchymal transition following SAR1A or RHOA knockdown; RHOA overexpression had the opposite effect. Following SAR1A knockdown, phalloidin staining indicated that osteosarcoma cells showed reduced lamellipodia formation. Endoplasmic reticulum stress levels and reactive oxygen species production were enhanced following the knockdown of SAR1A, as was autophagic activity, with lung metastases being reduced in vivo after such knockdown. Knocking down SAR1A suppresses osteosarcoma cell metastasis through the RhoA/YAP, ER stress, and autophagic pathways, offering new insights into the regulation of autophagic activity in the context of osteosarcoma cell metastasis and suggesting that these pathways could be amenable to therapeutic intervention.


Asunto(s)
Neoplasias Óseas , Neoplasias Pulmonares , Proteínas de Unión al GTP Monoméricas , Osteosarcoma , Adolescente , Humanos , Proteínas ras/metabolismo , Proliferación Celular , Línea Celular Tumoral , Osteosarcoma/patología , Neoplasias Óseas/patología , Autofagia/genética , Transducción de Señal , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Movimiento Celular/genética , Proteína de Unión al GTP rhoA/genética , Proteína de Unión al GTP rhoA/metabolismo , Proteínas de Unión al GTP Monoméricas/metabolismo
20.
Opt Express ; 30(8): 13356-13371, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35472950

RESUMEN

We propose and demonstrate a resolution-preserving passive 2D/3D convertible display by two individual wavelengths. It uses a holographic optical element to generate two images and passively separate the exit pupils for these two wavelengths, which forms two viewpoints for each of the observer's eyes. Due to Bragg-mismatched reconstruction of two similar but distinct wavelengths, the images are separated in space. They can be fused into one through the convergence function of human eyes. By switching the input image source, the conversion between 2D and 3D mode can be realized. This method is resolution-preserving and 2D/3D convertible with no extra active components. For experimental verification, a proof-of-concept projection-type prototype is assessed.

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