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1.
Opt Express ; 32(9): 15390-15409, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859191

RESUMO

Shock wave measurement is vital in assessing explosive power and designing warheads. To obtain satisfactory observation data of explosive shock waves, it is preferable for optical sensors to possess high-dynamic range and high-time resolution capabilities. In this paper, the event camera is first employed to observe explosive shock waves, leveraging its high dynamic range and low latency. A comprehensive procedure is devised to measure the motion parameters of shock waves accurately. Firstly, the plane lines-based calibration method is proposed to compute the calibration parameters of the event camera, which utilizes the edge-sensitive characteristic of the event camera. Then, the fitted ellipse parameters of the shock wave are estimated based on the concise event data, which are gained by utilizing the characteristics of the event triggering and shock waves' morphology. Finally, the geometric relationship between the ellipse parameters and the radius of the shock wave is derived, and the motion parameters of the shock wave are estimated. To verify the performance of our method, we compare our measurement results in the TNT explosion test with the pressure sensor results and empirical formula prediction. The relative measurement error compared to pressure sensors is the lowest at 0.33% and the highest at 7.58%. The experimental results verify the rationality and effectiveness of our methods.

2.
Medicine (Baltimore) ; 103(18): e38021, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701273

RESUMO

Uveal melanoma (UM) is a rare but aggressive malignant ocular tumor with a high metastatic potential and limited therapeutic options, currently lacking accurate prognostic predictors and effective individualized treatment strategies. Public databases were utilized to analyze the prognostic relevance of programmed cell death-related genes (PCDRGs) in UM transcriptomes and survival data. Consensus clustering and Lasso Cox regression analysis were performed for molecular subtyping and risk feature construction. The PCDRG-derived index (PCDI) was evaluated for its association with clinicopathological features, gene expression, drug sensitivity, and immune infiltration. A total of 369 prognostic PCDRGs were identified, which could cluster UM into 2 molecular subtypes with significant differences in prognosis and clinicopathological characteristics. Furthermore, a risk feature PCDI composed of 11 PCDRGs was constructed, capable of indicating prognosis in UM patients. Additionally, PCDI exhibited correlations with the sensitivity to 25 drugs and the infiltration of various immune cells. Enrichment analysis revealed that PCDI was associated with immune regulation-related biological processes and pathways. Finally, a nomogram for prognostic assessment of UM patients was developed based on PCDI and gender, demonstrating excellent performance. This study elucidated the potential value of PCDRGs in prognostic assessment for UM and developed a corresponding risk feature. However, further basic and clinical studies are warranted to validate the functions and mechanisms of PCDRGs in UM.


Assuntos
Melanoma , Neoplasias Uveais , Humanos , Neoplasias Uveais/genética , Neoplasias Uveais/mortalidade , Melanoma/genética , Melanoma/mortalidade , Melanoma/patologia , Prognóstico , Masculino , Feminino , Nomogramas , Biomarcadores Tumorais/genética , Transcriptoma , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Pessoa de Meia-Idade
3.
Theriogenology ; 209: 141-150, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37393744

RESUMO

DNA binding inhibitory factor 3 (ID3) has been shown to have a key role in maintaining proliferation and differentiation. It has been suggested that ID3 may also affect mammalian ovarian function. However, the specific roles and mechanisms are unclear. In this study, the expression level of ID3 in cumulus cells (CCs) was inhibited by siRNA, and the downstream regulatory network of ID3 was uncovered by high-throughput sequencing. The effects of ID3 inhibition on mitochondrial function, progesterone synthesis, and oocyte maturation were further explored. The GO and KEGG analysis results showed that after ID3 inhibition, differentially expressed genes, including StAR, CYP11A1, and HSD3B1, were involved in cholesterol-related processes and progesterone-mediated oocyte maturation. Apoptosis in CC was increased, while the phosphorylation level of ERK1/2 was inhibited. During this process, mitochondrial dynamics and function were disrupted. In addition, the first polar body extrusion rate, ATP production and antioxidation capacity were reduced, which suggested that ID3 inhibition led to poor oocyte maturation and quality. The results will provide a new basis for understanding the biological roles of ID3 as well as cumulus cells.


Assuntos
Células do Cúmulo , Oócitos , Oogênese , Progesterona , Animais , Bovinos , Feminino , Células do Cúmulo/metabolismo , Mamíferos , Mitocôndrias , Oócitos/fisiologia , Oogênese/genética , Progesterona/farmacologia , Progesterona/metabolismo , Proteínas Inibidoras de Diferenciação/metabolismo
4.
Nutrients ; 15(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37299390

RESUMO

Changes in the composition and ratio of the flora during colitis have been found to potentially affect ovarian function through nutrient absorption. However, the mechanisms have not been fully explored. To investigate whether colitis-induced dysbacteriosis of the intestinal flora affects ovarian function, mice were given dextran sodium sulfate (DSS) through drinking water. High-throughput sequencing technology was used to clarify the composition and proportion of bacterial flora as well as gene expression changes in the colon. Changes in follicle type, number, and hormone secretion in the ovary were detected. The results showed that 2.5% DSS could induce severe colitis symptoms, including increased inflammatory cell infiltration, severe damage to the crypt, and high expression of inflammatory factors. Moreover, vitamin A synthesis metabolism-related genes Rdh10, Aldh1a1, Cyp26a1, Cyp26b1, and Rarß were significantly decreased, as well as the levels of the steroid hormone synthase-related proteins STAR and CYP11A1. The levels of estradiol, progesterone, and Anti-Mullerian hormone as well as the quality of oocytes decreased significantly. The significantly changed abundances of Alistipes, Helicobacter, Bacteroides, and some other flora had potentially important roles. DSS-induced colitis and impaired vitamin A absorption reduced ovarian function.


Assuntos
Colite , Microbioma Gastrointestinal , Feminino , Camundongos , Animais , Vitamina A/metabolismo , Disbiose/metabolismo , Colite/metabolismo , Colo/metabolismo , Hormônios/metabolismo , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
5.
Vet Med Sci ; 9(1): 326-335, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36446749

RESUMO

BACKGROUND: T-box transcription factor 2 (TBX2) is a member of T-box gene family whose members are highly conserved in evolution and encoding genes and are involved in the regulation of developmental processes. The encoding genes play an important role in growth and development. Although TBX2 has been widely studied in cancer cell growth and development, its biological functions in bovine cumulus cells remain unclear. OBJECTIVES: This study aimed to investigate the regulatory effects of TBX2 in bovine cumulus cells. METHODS: TBX2 gene was knockdown with siRNA to clarify the function in cellular physiological processes. Cell proliferation and cycle changes were determined by xCELLigence cell function analyzer and flow cytometry. Mitochondrial membrane potential and autophagy were detected by fluorescent dye staining and immunofluorescence techniques. Western blot and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) were used to detect the expression changes of proliferation and autophagy-related proteins. Aadenosine triphosphate (ATP) production, glucose metabolism, and cholesterol synthesis of cumulus cells were measured by optical density and chemiluminescence analysis. RESULTS: After inhibition of TBX2, the cell cycle was disrupted. The levels of apoptosis, ratio of light chain 3 beta II/I, and reactive oxygen species were increased. The proliferation, expansion ability, ATP production, and the amount of cholesterol secreted by cumulus cells were significantly decreased. CONCLUSIONS: TBX2 plays important roles in regulating the cells' proliferation, expansion, apoptosis, and autophagy; maintaining the mitochondrial function and cholesterol generation of bovine cumulus cells.


Assuntos
Autofagia , Células do Cúmulo , Feminino , Animais , Bovinos , Células do Cúmulo/metabolismo , Proliferação de Células , Apoptose/genética , Mitocôndrias , Colesterol/metabolismo , Colesterol/farmacologia , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia
6.
Front Genet ; 13: 934829, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36452153

RESUMO

Purpose: The study aimed to report a rare case of a patient with Alport syndrome, which was manifested as unilateral non-infectious uveitis after bilateral cataract surgery. Methods: A case report. Results: A 2-year-old boy was diagnosed with unilateral panuveitis based on the clinical and multimodal imaging findings. Intraocular fluid samples for metagenomic next-generation sequencing (mNGS) and microbial culture were negative. However, urine tests found proteinuria and microscopic hematuria. Pathologic findings of the kidney revealed a thickened membrane, and a diagnosis of Alport syndrome was considered. Gene analysis found deletions in exon 1 of COL4A5 and exons 1 and 2 of COL4A6. The uveitis resolved gradually, following the administration of oral steroids. Conclusion: Uveitis may be an ocular manifestation of Alport syndrome.

7.
Front Bioeng Biotechnol ; 10: 905516, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36452207

RESUMO

With continued expansion of the aged population, the number of patients with retinal degeneration, which is a leading cause of vision loss worldwide, is growing. Stem cell therapies offer hope for regeneration and repair of damaged retinal tissue. Recent reports have highlighted stem cell-derived paracrine mediators, such as exosomes, which appear to exert a therapeutic benefit similar to their cell of origin and do not carry the risk of cell transplantation. One speculated role is that exosomes likely mediate intercellular communication and material exchange. This review depicts the molecular mechanisms underlying exosome-based therapy, especially in retina degeneration diseases. In the future, the use of stem cell-derived exosomes could be considered a novel and cell-free therapeutic strategy in regenerative medicine.

8.
Sci Rep ; 12(1): 13203, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915140

RESUMO

To improve the multidirectional motion control accuracy and driving stability of Distributed Drive Autonomous Vehicles (DDAVs) under extreme conditions, the extreme speed estimation method based on dynamic boundary and the multidirectional motion coupling control law design method based on multi degrees of freedom vehicle dynamic model are proposed. The extreme speed estimation method identifies the stable state of DDAVs by the dynamic boundary composed of yaw rate, sideslip angle and roll angle, and then estimates the extreme speed of the vehicle. The design method of multidirectional motion coupling control law adopts eight-degrees-of-freedom (8-DOF) vehicle dynamic model to design path tracking control law, speed tracking control law, yaw stability control law, and active suspension control law at the same time, so as to realize multidirectional motion coupling control. Based on the above method, the Multidirectional Motion Coupling Control System (MMCCS) of DDAVs is designed. The effectiveness of the proposed method is verified by double-line-shifting and serpentine driving simulations under different road adhesion conditions. The superiority of the method is proved by comparing the existing integrated control method.

9.
Adv Sci (Weinh) ; 9(27): e2202408, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35780486

RESUMO

Perovskite light-emitting diodes (LEDs) are emerging light sources for next-generation lighting and display technologies; however, their development is greatly plagued by difficulty in achieving yellow electroluminescence, environmental instability, and lead toxicity. Copper halide CsCu2 I3 with intrinsic yellow emission emerges as a highly promising candidate for eco-friendly LEDs, but the electroluminescent performance is limited by defect-related nonradiative losses and inefficient charge transport/injection. To solve these issues, a hole-transporting poly(9-vinlycarbazole) (PVK)-incorporated engineering into CsCu2 I3 emitter is proposed. PVK with carbazole groups is permeated at the grain boundaries of CsCu2 I3 films by interacting with the uncoordinated Cu+ , reducing the CuCs and CuI antisite defects to increase the radiative recombination and enhancing the hole mobility to balance the charge transport/injection, resulting in substantially enhanced device performances. Eventually, the yellow LEDs exhibit an 8.5-fold enhancement of external quantum efficiency, and the half-lifetime reaches 14.6 h, representing the most stable yellow LEDs based on perovskite systems reported so far.

10.
Appl Opt ; 60(22): 6479-6486, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34612883

RESUMO

The relative pose estimation of uncooperative spacecraft is an essential technology in space missions. However, lacking the prior knowledge of uncooperative targets brings great challenges to accurately measure their pose, which hinders their application in space. To overcome these problems, an accurate and robust pose estimation approach for uncooperative spacecraft is proposed based on a time-of-flight camera coupled with a gray-scale camera. We reconstruct the target model using our hierarchical registration strategy by the ToF camera and extract 2D lines from image sequences captured by the gray-scale camera. We attempt to establish 2D-3D line correspondences for pose estimation, which effectively associates the 2D image information with the reconstructed 3D model. Experimental results manifest that, when dealing with a completely unknown model, our method computes its relative position and attitude with significantly high accuracy.

11.
Molecules ; 23(9)2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30213061

RESUMO

A versatile and practical "on-water" protocol was newly developed to synthesize quinazolinones using o-bromobenzonitrile as a novel starting material. Studies have found that air as well as water plays an important role in synthesis of quinazolinones. Further investigation indicated that dihydroquinazolinones can be prepared with this protocol under the protection of N2. The protocol can be extended to other substrates and various quinazolinones and dihydroquinazolinones were obtained. o-Bromobenzamide, o-aminobenzonitrile, and o-aminobenzamide were also evaluated as starting materials, and the results further proved the versatility of this protocol, especially towards dihydroquinazolinones.


Assuntos
Benzamidas/química , Quinazolinonas/síntese química , Água/química , Estrutura Molecular , Nitrilas/química , Quinazolinonas/química
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