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1.
PLoS Pathog ; 20(10): e1012649, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39453974

RESUMEN

Cottontail rabbit papillomavirus (CRPV), the first papillomavirus associated with tumor development, has been used as a powerful model to study papillomavirus pathogenesis for more than 90 years. However, lack of a comprehensive analysis of the CRPV transcriptome has impeded the understanding of CRPV biology and molecular pathogenesis. Here, we report the construction of a complete CRPV transcription map from Hershey CRPV-induced skin tumor tissues. By using RNA-seq in combination with long-reads PacBio Iso-seq, 5' and 3' RACE, primer-walking RT-PCR, Northern blot, and RNA in situ hybridization, we demonstrated that the CRPV genome transcribes its early and late RNA transcripts unidirectionally from at least five distinct major promoters (P) and polyadenylates its transcripts at two major polyadenylation (pA) sites. The viral early transcripts are primarily transcribed from three "early" promoters, P90, P156, and P907 and polyadenylated at nt 4368 by using an early polyadenylation signal (PAS) at nt 4351. Like other low-risk human papillomaviruses and animal papillomaviruses, CRPV E6 and E7 transcripts are transcribed from three separate early promoters. Transcripts from two "late" promoters, P7525, and P1225, utilize either an early PAS for E1^E4 or a late PAS at 7399 for L2 and L1 RNA polyadenylation at nt 7415 to express capsid L2 and L1 proteins respectively. By using the mapped four 5' splice sites and three 3' splice sites, CRPV RNA transcripts undergo extensive alternative splicing to produce more than 33 viral RNA isoforms for production of at least 12 viral proteins, some of which without codon optimization are expressible in rabbit RK13 and human HEK293T cells. The constructed full CRPV transcription map in this study for the first time will enhance our understanding of the structures and expressions of CRPV genes and their contribution to molecular pathogenesis and tumorigenesis.


Asunto(s)
Papillomavirus del Conejo de Rabo Blanco , Infecciones por Papillomavirus , Animales , Conejos , Papillomavirus del Conejo de Rabo Blanco/genética , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/metabolismo , Regiones Promotoras Genéticas , Neoplasias Cutáneas/virología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Transcripción Genética , Genoma Viral , ARN Viral/genética , ARN Viral/metabolismo
2.
J Transl Med ; 22(1): 368, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637886

RESUMEN

In this study, we investigated CD70 as a promising target for renal cell carcinoma (RCC) therapy and developed a potent chimeric antigen receptor T (CAR-T) cells for potential clinical testing. CD70, found to be highly expressed in RCC tumors, was associated with decreased survival. We generated CAR-T cells expressing VHH sequence of various novel nanobodies from immunized alpaca and a single-chain variable fragment (scFv) derived from human antibody (41D12). In our in vitro experiments, anti-CD70 CAR-T cells effectively eliminated CD70-positive tumor cells while sparing CD70-negative cells. The nanobody-based CAR-T cells demonstrated significantly higher production of cytokines such as IL-2, IFN-γ and TNF-ɑ during co-culture, indicating their potential for enhanced functionality. In xenograft mouse model, these CAR-T cells exhibited remarkable anti-tumor activity, leading to the eradication of RCC tumor cells. Importantly, human T cell expansion after infusion was significantly higher in the VHH groups compared to the scFv CAR-T group. Upon re-challenging mice with RCC tumor cells, the VHH CAR-T treated group remained tumor-free, suggesting a robust and long-lasting anti-tumor response. These findings provide strong support for the potential of nanobody-based CD70 CAR-T cells as a promising therapeutic option for RCC. This warrants further development and consideration for future clinical trials and applications.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Receptores Quiméricos de Antígenos , Humanos , Animales , Ratones , Carcinoma de Células Renales/terapia , Linfocitos T , Línea Celular Tumoral , Neoplasias Renales/terapia , Inmunoterapia Adoptiva , Ensayos Antitumor por Modelo de Xenoinjerto , Ligando CD27
3.
Inorg Chem ; 2024 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-39496554

RESUMEN

The hexagonal perovskite derivatives Ba3M'M″O8.5 featuring a hybrid structure composed of 9R hexagonal perovskite and palmierite structure motifs exhibit significant oxide ionic conductivity due to the highly disordered oxide-ion and M-cation sublattices. Herein, we report the structure and electrical properties of the perovskite Ba3Ti0.4W1.6O8.6. Three-dimensional (3D) electron diffraction (ED), neutron powder diffraction (NPD), and neutron pair distribution functions (nPDF) revealed a 9R hexagonal perovskite structure for Ba3Ti0.4W1.6O8.6 with fully occupied central M2 sites, partially occupied outer M1 sites, and oxygen-deficient cubic c-BaO2.6 sublayers. These cation and oxygen arrangements differ significantly from those in Ba3M'M″O8.5 and enable Ba3Ti0.4W1.6O8.6 to capture atmospheric water and O2, resulting in triple conduction (oxide ion, proton, and hole) under wet air conditions. Proton and oxide ion conductions predominate at temperatures <400 and >650 °C in wet Ar and dry air, respectively. Bond-valence site energy calculations, together with structure analysis, deciphered that the two-dimensional oxide-ion diffusion pathways along the c-BaO2.6 layers are disrupted by the M1 vacancies, thereby resulting in relatively low oxide ionic conductivity. Our findings open up a new strategy of utilizing the cation's propensity of coordination geometry to design new oxygen- and B-site-deficient perovskites and thus achieve desired conductivity.

4.
Sensors (Basel) ; 24(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38276342

RESUMEN

Current research on the interference of GNSS (Global Navigation Satellite System) array antennas focuses on the single interference effect and the improvement of interference hardware capability, while the multi-degree-of-freedom (DOF) interference model and mechanism remain to be fully studied. Aiming at this problem, this paper analyzes the preconditions for the definition of anti-jamming degrees of freedom and the characteristics of super-DOF interference through formula derivation and simulation. First, by analyzing the influence of the number of interfering signals on the angular resolution, the prerequisite of the definition of anti-interference degrees of freedom in the airspace is proposed. Second, the definition of anti-interference degrees of freedom is used to calculate the change rule of the critical power of the interference under different numbers of interfering signals. Finally, the influence of super-DOF interference on the array antenna is analyzed. The results show that the prerequisite for the anti-interference freedom of the array antenna is that the distribution interval of the interfering signal is greater than 15°, taking a four-array element uniform circular array antenna as an example. The critical interference power of the array antenna decreases by about 15 dB when the number of interfering signals exceeds the degrees of freedom of the array antenna's interference immunity, provided that the interference resolution is satisfied. The conclusions of this paper give the critical power change rule of multi-DOF interference and the effect of super-DOF interference, as well as the prerequisites for the setting of interference signals, which can be used, for example, in the deployment of distributed interference sources and the development of anti-jamming algorithms.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38652217

RESUMEN

Thrombus age determination in fatal venous thromboembolism cases is an important task for forensic pathologists. In this study, we investigated the time-dependent expressions of formyl peptide receptor 2 (FPR2) and Annexin A1 (ANXA1) in a stasis-induced deep vein thrombosis (DVT) murine model, with the aim of obtaining useful information for thrombus age timing. A total of 75 ICR mice were randomly classified into thrombosis group and control group. In thrombosis group, a DVT model was established by ligating the inferior vena cava (IVC) of mice, and thrombosed IVCs were harvested at 1, 3, 5, 7, 10, 14, and 21 days after modeling. In control group, IVCs without thrombosis were taken as control samples. The expressions of FPR2 and ANXA1 during thrombosis were detected using immunohistochemistry and double immunofluorescence staining. Their protein and mRNA levels in the samples were determined by Western blotting and quantitative real-time PCR. The results reveal that FPR2 was predominantly expressed by intrathrombotic neutrophils and macrophages. ANXA1 expression in the thrombi was mainly distributed in neutrophils, endothelial cells of neovessels, and fibroblastic cells. After thrombosis, the expressions of FPR2 and ANXA1 were time-dependently up-regulated. The percentage of FPR2-positive cells and the level of FPR2 protein significantly elevated at 1, 3, 5 and 7 days after IVC ligation as compared to those at 10, 14 and 21 days after ligation (p < 0.05). Moreover, the mRNA level of FPR2 were significantly higher at 5 days than that at the other post-ligation intervals (p < 0.05). Besides, the levels of ANXA1 mRNA and protein peaked at 10 and 14 days after ligation, respectively. A significant increase in the mRNA level of ANXA1 was found at 10 and 14 days as compared with that at the other post-ligation intervals (p < 0.01). Our findings suggest that FPR2 and ANXA1 are promising as useful markers for age estimation of venous thrombi.

6.
Zhongguo Zhong Yao Za Zhi ; 49(11): 3040-3049, 2024 Jun.
Artículo en Zh | MEDLINE | ID: mdl-39041164

RESUMEN

This study aims to explore the effect of Lycii Fructus and Salviae Miltiorrhizae Radix et Rhizoma(LFSMR), a drug pair possesses the function of nourishing Yin, promoting blood circulation, and brightening the eyes, in treating retinitis pigmentosa(RP)by inhibiting the gliosis of Müller cells(MCs) and inducing their reprogramming and differentiation into various types of retinal nerve cells. Twelve C57 mice were used as the normal control group, and 48 transgenic RP(rd10) mice were randomly divided into the model group, positive control group, and low and high dose LFSMR groups, with 12 mice in each group. HE staining was used to detect pathological changes in the retina, and an electroretinogram was used to detect retinal function. Retinal optical coherence tomography was used to detect retinal thickness and perform fundus photography, and laser speckle perfusion imaging was used to detect local retinal blood flow. Digital PCR was used to detect gene expression related to retinal nerve cells, and immunofluorescence was used to detect protein expression related to retinal nerve cells. LFSMR could significantly improve the pathological changes, increase the amplitude of a and b waves, increase the retinal thickness, restore retinal damage, and increase retinal blood flow in mice with RP lesions. LFSMR could also significantly inhibit the m RNA expression of the glial fibrillary acidic protein( GFAP) during the pathogenesis of RP and upregulate m RNA expression of sex determining region Y box protein 2(SOX2), paired box protein 6(Pax6),rhodopsin, protein kinase C-α(PKCα), syntaxin, and thymic cell antigen 1. 1(Thy1. 1). LFSMR could significantly inhibit GFAP protein expression and enhance protein expression of SOX2, Pax6, rhodopsin, PKCα, syntaxin, and Thy1. 1. It could also reverse the pathological changes in the retina of rd10 mice, improve retinal function and fundus performance, increase retinal thickness, enhance local retinal blood flow, and exert therapeutic effects on RP. The mechanism of action of LFSMR may be related to inhibiting the gliosis of MCs and promoting their reprogramming and differentiation into various types of retinal nerve cells.


Asunto(s)
Medicamentos Herbarios Chinos , Células Ependimogliales , Lycium , Ratones Endogámicos C57BL , Retinitis Pigmentosa , Salvia miltiorrhiza , Animales , Ratones , Células Ependimogliales/efectos de los fármacos , Células Ependimogliales/metabolismo , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/administración & dosificación , Lycium/química , Retinitis Pigmentosa/tratamiento farmacológico , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/metabolismo , Retinitis Pigmentosa/fisiopatología , Salvia miltiorrhiza/química , Masculino , Retina/efectos de los fármacos , Rizoma/química , Humanos
7.
Plant J ; 110(1): 129-146, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34981873

RESUMEN

Enzymes are essential components of all biological systems. The key characteristics of proteins functioning as enzymes are their substrate specificities and catalytic efficiencies. In plants, most genes encoding enzymes are members of large gene families. Within such families, the contributions of active site motifs to the functional divergence of duplicate genes have not been well elucidated. In this study, we identified 41 glutaredoxin (GRX) genes in the Populus trichocarpa genome. GRXs are ubiquitous enzymes in plants that play important roles in developmental and stress tolerance processes. In poplar, GRX genes were divided into four classes based on clear differences in gene structure and expression pattern, subcellular localization, enzymatic activity, and substrate specificity of the encoded proteins. Using site-directed mutagenesis, this study revealed that the divergence of the active site motif among different classes of GRX proteins resulted in substrate switches and thus provided new insights into the molecular evolution of these important plant enzymes.


Asunto(s)
Populus , Dominio Catalítico , Regulación de la Expresión Génica de las Plantas/genética , Glutarredoxinas/genética , Humanos , Filogenia , Proteínas de Plantas/metabolismo , Populus/metabolismo
8.
Crit Rev Food Sci Nutr ; : 1-15, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37222573

RESUMEN

In this review, the physicochemical and conformational changes of myofibrillar proteins (MPs) of freeze-induced mince-based aquatic foods were comprehensively summarized in depth. Studies have demonstrated that temperature fluctuation and long-time freezing negatively affect food quality, resulting in texture alteration, drip fluid, flavor degradation, and nutrition loss due to MPs denaturation, aggregation, and oxidation. Attempts have been made in ice-recrystallization inhibition, freezing point depression, and ice shape and growth control for better cryopreservation. Moreover, to further minimize the quality deterioration, cryoprotectants were acknowledged to reduce the denaturation and aggregation of the MPs effectively. Recently, interest in novel functional ingredients, including oligosaccharides, protein hydrolysates, and natural polyphenols demonstrated excellent cryoprotective effects while avoiding health concerns and undesirable flavor caused by traditional sugar-based or phosphates-based cryoprotectants. Therefore, the present review provides a systematic overview of these low molecular weight multifunctional substances with a particular sequence and highlights their underlying mechanism in the inhibition of ice recrystallization the stabilization of MPs.

9.
Inorg Chem ; 62(14): 5872-5879, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-36978229

RESUMEN

The d10 metal oxides with low effective mass and high mobility of photoexcited electrons have received much attention in photocatalytic water splitting. However, there are still challenges in practical application due to insufficient visible light absorption. Here, an unusual phenomenon of the In2+ cation in PtIn6(GeO4)2O and PtIn6(Ga/InO4)2 with a narrow band gap is systematically investigated using density functional theory calculations. According to chemical bond analysis, the final band edge structure results from the interaction between the empty In-5p orbitals and the occupied antibonding state of the In 5s-O 2p orbitals as well as the further hybridization of adjacent In cations in PtIn6 octahedrons. The unique bonding characteristic of In2+ cations endows them with a narrow band gap and visible light response ability. Moreover, the occupied antibonding state could weaken the strength of the In-O covalent bond and strengthen the orbital hybridization of the In-In bond, causing the conduction band minimum to be located in the electroactive In6 cavity. This work reveals the origin of the narrow band gap of PtIn6(GeO4)2O and PtIn6(Ga/InO4)2 in view of bond theory and shows that they are promising semiconductors for the application of photocatalytic H2 generation.

10.
Environ Res ; 237(Pt 1): 116895, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37586454

RESUMEN

BACKGROUND: The cancer-testis protein melanoma antigen A3 (MAGE-A3) is highly expressed in a broad range of malignant tumor forms. It has been confirmed that affibody molecules, a novel family of small (∼6.5 kDa) targeting proteins, are useful agents for molecular imaging and targeted tumor treatment. As a novel agent for in vivo molecular imaging detection of MAGE-A3-positive tumors, the efficacy of affibody molecules was assessed in this research. METHODS: In this study, three cycles of phage display library screening resulted in the isolation of two new affibody molecules (ZMAGE-A3:172 and ZMAGE-A3:770) that attach to MAGE-A3. These molecules were then expressed in bacteria and purified. The affibody molecules with high affinity and specificity were evaluated using western blotting, immunohistochemistry, indirect immunofluorescence, surface plasmon resonance, and near-infrared optical imaging of tumor-bearing nude mice. RESULTS: The selected ZMAGE-A3 affibodies can precisely bind to the MAGE-A3 protein in living cells and display high-affinity binding to the MAGE-A3 protein at the molecular level. Furthermore, the accumulation of DyLight755-labeled ZMAGE-A3:172 or ZMAGE-A3:770 in MAGE-A3-positive tumors was achieved as early as 30 min and disappeared at 48 h post-injection. CONCLUSION: Our findings support the potential of the two MAGE-A3 protein-binding affibody molecules for their use as molecular imaging agents.

11.
Cardiol Young ; 33(2): 183-189, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35086607

RESUMEN

Cardiac involvement associated with multi-system inflammatory syndrome in children has been extensively reported, but the prevalence of cardiac involvement in children with SARS-CoV-2 infection in the absence of inflammatory syndrome has not been well described. In this retrospective, single centre, cohort study, we describe the cardiac involvement found in this population and report on outcomes of patients with and without elevated cardiac biomarkers. Those with multi-system inflammatory syndrome in children, cardiomyopathy, or complex CHD were excluded. Inclusion criteriaz were met by 80 patients during the initial peak of the pandemic at our institution. High-sensitivity troponin T and/or N-terminal pro-brain type natriuretic peptide were measured in 27/80 (34%) patients and abnormalities were present in 5/27 (19%), all of whom had underlying comorbidities. Advanced respiratory support was required in all patients with elevated cardiac biomarkers. Electrocardiographic abnormalities were identified in 14/38 (37%) studies. Echocardiograms were performed on 7/80 patients, and none demonstrated left ventricular dysfunction. Larger studies to determine the true extent of cardiac involvement in children with COVID-19 would be useful to guide recommendations for standard workup and management.


Asunto(s)
COVID-19 , Humanos , Niño , Adolescente , COVID-19/epidemiología , Estudios Retrospectivos , SARS-CoV-2 , Estudios de Cohortes , Biomarcadores , Péptido Natriurético Encefálico
12.
J Sci Food Agric ; 103(2): 524-533, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36054511

RESUMEN

BACKGROUND: The contribution and mechanism of κ-/ι-carrageenan (CG) with different hydration characteristics on the gelling properties of shrimp myofibrillar protein (MP) gelation was studied. RESULTS: The gel strength, water-holding capacity and viscoelastic properties of MP gels were significantly enhanced by 1.0% κ-/ι-CG (P < 0.05), but the microstructure showed that excessive carrageenan caused fragmentation of the gel network and a corresponding decrease in gel properties. Compared to MP-ιCG, MP-κCG showed larger breaking force and shorter breaking distance, thus enhancing the hardness and brittleness of the gel, which might be ascribed to a reinforced network skeleton and a tighter binding of κCG-myosin. However, MP-ιCG stabilized more moisture in the gel network, thereby improving the tenderness of the gel, which might be related to the electrostatic repulsion observed between the sulfate groups of ιCG and the myosin observed by molecular docking. In addition, the ß-sheet content and intermolecular interactions might be positively correlated with gel properties. CONCLUSION: In this study, a composite gel system was constructed based on the interaction of MP and CG. The quality differences of two kinds of CG-MP gels were clarified, which will provide guidance for the application of different kinds of carrageenan and the development of recombinant meat products with specific quality. © 2022 Society of Chemical Industry.


Asunto(s)
Coloides , Proteínas , Carragenina/química , Simulación del Acoplamiento Molecular , Geles/química , Miosinas , Reología
13.
Carcinogenesis ; 43(5): 479-493, 2022 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-35134836

RESUMEN

Human papillomavirus (HPV) E7 oncogene plays the most important role in cervical cancer. However, whether E7 oncoprotein is continuously expressed, associated with AKT(Ser473)/p-Src(Tyr527) signaling to trigger cervical carcinogenesis remains unclear. Here, we explored first if HPV16 E7 oncoprotein could be detected in clinical biopsies and is sustainedly expressed, and then investigated how this oncoprotein interacted with AKT(Ser473)/p-Src(Tyr527) signaling in cancer progression. We used ZHPV16E7384 affibody to detect E7 expression in HPV16-positive cervical cancer biopsies and animal tumors by immunohistochemistry (IHC). Results showed that ZHPV16E7384 affibody had intense and specific staining for E7 oncoprotein in the detected specimen. The E7 oncoprotein was continuously expressed to correspond with the development of precancerous lesions to invasive cervical cancer. IHC staining also revealed that AKT, p-AKT(Ser473), Src and p-Src(Tyr527) proteins were expressed in both patient biopsies and animal tumors, with the highest levels of p-AKT(Ser473)/p-Src(Tyr527) present in invasive cancer. Furthermore, siRNA experiments revealed that HPV16 E7 knockdown significantly impaired expression of p-AKT(Ser473)/p-Src(Tyr527) in both HPV16 E7-positive cancer cells and transformed cells. In addition, transient expression of HPV16 E7 protein promoted significantly expression of p-AKT(Ser473)/p-Src(Tyr527) in primary human keratinocytes. Finally, co-immunoprecipitation analysis proved that HPV 16 E7 protein interacted reciprocally with p-AKT(Ser473)/p-Src(Tyr527). In conclusion, we demonstrate that HPV16 E7 oncoprotein is continuously expressed to promote expression of p-AKT(Ser473)/p-Src(Tyr527) leading to drive the initiation and progression of cervical cancer. Our data provide a novel insight that HPV16 E7 activates p-AKT(Ser473)/p-Src(Tyr527) to establish a mechanistic link between the oncogene and the AKT/Src signaling to trigger cervical carcinogenesis.


Asunto(s)
Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Lesiones Precancerosas , Neoplasias del Cuello Uterino , Animales , Carcinogénesis , Femenino , Humanos , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Lesiones Precancerosas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Neoplasias del Cuello Uterino/patología
14.
Plant J ; 108(6): 1597-1608, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34612535

RESUMEN

Maize leaf angle (LA) is a complex quantitative trait that is controlled by developmental signals, hormones, and environmental factors. However, the connection between histone methylation and LAs in maize remains unclear. Here, we reported that SET domain protein 128 (SDG128) is involved in leaf inclination in maize. Knockdown of SDG128 using an RNA interference approach resulted in an expanded architecture, less large vascular bundles, more small vascular bundles, and larger spacing of large vascular bundles in the auricles. SDG128 interacts with ZmGID2 both in vitro and in vivo. Knockdown of ZmGID2 also showed a larger LA with less large vascular bundles and larger spacing of vascular bundles. In addition, the transcription level of cell wall expansion family genes ZmEXPA1, ZmEXPB2, and GRMZM2G005887; transcriptional factor genes Lg1, ZmTAC1, and ZmCLA4; and auxin pathway genes ZmYUCCA7, ZmYUCCA8, and ZmARF22 was reduced in SDG128 and ZmGID2 knockdown plants. SDG128 directly targets ZmEXPA1, ZmEXPB2, LG1, and ZmTAC1 and is required for H3K4me3 deposition at these genes. Together, the results of the present study suggest that SDG128 and ZmGID2 are involved in the maize leaf inclination.


Asunto(s)
Hojas de la Planta/fisiología , Proteínas de Plantas/genética , Zea mays/fisiología , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Regulación de la Expresión Génica de las Plantas , Histonas , Ácidos Indolacéticos/metabolismo , Mutación , Hojas de la Planta/citología , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Interferencia de ARN , Zea mays/citología
15.
Opt Express ; 30(11): 18638-18654, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-36221661

RESUMEN

There exists the contradiction between imaging efficiency and imaging quality for Fourier single-pixel imaging (FSI). Although the deep learning approaches have solved this problem to some extent, the reconstruction quality at low sampling rate is still not enough to meet the practical requirements. To solve this problem, inspired by the idea of super-resolution, this paper proposes the paralleled fusing of the U-net and attention mechanism to improve the quality of FSI reconstruction at a low sampling rate. This paper builds a generative adversarial network structure to achieve recovery of high-resolution target images from low-resolution FSI reconstruction results under low sampling rate conditions. Compared with conventional FSI and other deep learning methods based on FSI, the proposed method can get better quality and higher resolution results at low sampling rates in simulation and experiments. This approach is particularly important to high-speed Fourier single pixel imaging applications.

16.
Opt Express ; 30(18): 32948-32964, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36242346

RESUMEN

A single photon avalanche diode (SPAD) is a high sensitivity detector that can work under weak echo signal conditions (≤1 photon per pixel). The measured digital signals can be used to invert the range and reflectivity images of the target with photon-efficient imaging reconstruction algorithm. However, the existing photon-efficient imaging reconstruction algorithms are susceptible to noise, which leads to poor quality of the reconstructed range and reflectivity images of target. In this paper, a non-local sparse attention encoder (NLSA-Encoder) neural network is proposed to extract the 3D information to reconstruct both the range and reflectivity images of target. The proposed network model can effectively reduce the influence of noise in feature extraction and maintain the capability of long-range correlation feature extraction. In addition, the network is optimized for reconstruction speed to achieve faster reconstruction without performance degradation, compared with other existing deep learning photon-efficient imaging reconstruction methods. The imaging performance is verified through numerical simulation, near-field indoor and far-field outdoor experiments with a 64 × 64 SPAD array. The experimental results show that the proposed network model can achieve better results in terms of the reconstruction quality of range and reflectivity images, as well as reconstruction speed.

17.
Inorg Chem ; 61(34): 13413-13420, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-35972288

RESUMEN

Cation disorder in hydroxide-based perovskites remains relatively under-researched. In this work, novel hydroxide-based perovskite Sn1/3Na2/3Sn(OH)6 was first fabricated by a direct hydrothermal method, and its ability to photodegrade 2,4-dichlorophenol was evaluated. The synthesized photocatalyst is isostructural with MSn(OH)6 (M = Mg, Ca, Sr, Mn, Fe, Co, Ni, or Zn), where the M site is occupied by disordered Sn4+/Na+. Sn1/3Na2/3Sn(OH)6 exhibits outstanding photocatalytic activity under ultraviolet light. Specifically, 99% of 2,4-DCP is photodegraded in 40 min, with approximately 94% of its total chlorine content converted to Cl- anions. Radical trapping experiments indicated that superoxide radical anions (·O2-) play a critical role during the photocatalytic process. Finally, liquid chromatography-tandem mass spectrometry was conducted to monitor the photocatalytic intermediates. Overall, our findings demonstrate that hydroxide-based perovskites with cation disorder show promise for application in photocatalysis.


Asunto(s)
Clorofenoles , Compuestos de Calcio , Catálisis , Hidróxidos , Óxidos , Titanio
18.
Sensors (Basel) ; 22(16)2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-36015921

RESUMEN

Underwater ghost imaging based on deep learning can effectively reduce the influence of forward scattering and back scattering of water. With the help of data-driven methods, high-quality results can be reconstructed. However, the training of the underwater ghost imaging requires enormous paired underwater datasets, which are difficult to obtain directly. Although the Cycle-GAN method solves the problem to some extent, the blurring degree of the fuzzy class of the paired underwater datasets generated by Cycle-GAN is relatively unitary. To solve this problem, a few-shot underwater image generative network method is proposed. Utilizing the proposed few-shot learning image generative method, the generated paired underwater datasets are better than those obtained by the Cycle-GAN method, especially under the condition of few real underwater datasets. In addition, to reconstruct high-quality results, an underwater deblurring ghost imaging method is proposed. The reconstruction method consists of two parts: reconstruction and deblurring. The experimental and simulation results show that the proposed reconstruction method has better performance in deblurring at a low sampling rate, compared with existing underwater ghost imaging methods based on deep learning. The proposed reconstruction method can effectively increase the clarity degree of the underwater reconstruction target at a low sampling rate and promotes the further applications of underwater ghost imaging.

19.
Nano Lett ; 21(6): 2634-2641, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33656896

RESUMEN

Graphene/hexagonal boron nitride (h-BN) van der Waals (vdW) heterostructure has aroused great interest because of the unique Moiré pattern. In this study, we use molecular dynamics simulation to investigate the influence of the interlayer rotation angle θ on the interfacial thermal transport across graphene/h-BN heterostructure. The interfacial thermal conductance G of graphene/h-BN interface reaches 509 MW/(m2K) at 500 K without rotation, and it decreases monotonically with the increase of the rotation angle, exhibiting around 50% reduction of G with θ = 26.33°. The phonon transmission function reveals that G is dominantly contributed by the low-frequency phonons below 10 THz. Upon rotation, the surface fluctuation in the interfacial graphene layer is enhanced, and the transmission function for the low-frequency phonon is reduced with increasing θ, leading to the rotation angle-dependent G. This work uncovers the physical mechanisms for controlling interfacial thermal transport across vdW heterostructure via interlayer rotation.

20.
Int J Mol Sci ; 23(7)2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35409186

RESUMEN

Catalases (CATs) are important self-originating enzymes and are involved in many of the biological functions of plants. Multiple forms of CATs suggest their versatile role in lesion mimic mutants (LMMs), H2O2 homeostasis and abiotic and biotic stress tolerance. In the current study, we identified a large lesion mimic mutant9428 (llm9428) from Ethyl-methane-sulfonate (EMS) mutagenized population. The llm9428 showed a typical phenotype of LMMs including decreased agronomic yield traits. The histochemical assays showed decreased cell viability and increased reactive oxygen species (ROS) in the leaves of llm9428 compared to its wild type (WT). The llm9428 showed enhanced blast disease resistance and increased relative expression of pathogenesis-related (PR) genes. Studies of the sub-cellular structure of the leaf and quantification of starch contents revealed a significant decrease in starch granule formation in llm9428. Genetic analysis revealed a single nucleotide change (C > T) that altered an amino acid (Ala > Val) in the candidate gene (Os03g0131200) encoding a CATALASE C in llm9428. CRISPR-Cas9 targetted knockout lines of LLM9428/OsCATC showed the phenotype of LMMs and reduced starch metabolism. Taken together, the current study results revealed a novel role of OsCATC in starch metabolism in addition to validating previously studied functions of CATs.


Asunto(s)
Oryza , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Peróxido de Hidrógeno/metabolismo , Mutación , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Almidón/metabolismo
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