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1.
Poult Sci ; 103(9): 103989, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38981362

RESUMO

Protein arginine methyltransferases (PRMTs) in mammals play a role in various signaling pathways, such as virus infection, inflammasome responses, and cancer growth. While some PRMTs have been found to regulate interferon production in mammals, the mechanism in chickens remains to be fully understood. This study focused on investigating the function of chicken PRMTs. Our findings indicate that chicken PRMTs act as inhibitors of interferon production in response to dsRNA or MDA5 stimulation. Each PRMT is involved in different stages of interferon induction through the MDA5-MAVS-TBK1 pathway. Furthermore, we observed the colocalization of multiple PRMTs with the viral protein VP3 of infectious bursal disease virus (IBDV). Among the chicken PRMTs studied, PRMT3 was found to be widely expressed in various organs and its expression was upregulated during IBDV infection. Notably, PRMT3 supported IBDV replication, as demonstrated by ectopic expression and inhibition studies using SGC-707. Silencing of PRMT3 led to enhanced interferon production and inhibition of IBDV replication. This study provides novel insights into the role of chicken PRMTs, particularly PRMT3, in promoting IBDV replication by suppressing interferon signaling.

2.
Neural Regen Res ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38993141

RESUMO

ABSTRACT: Recent studies have suggested that abnormal acidification of lysosomes induces autophagic accumulation of amyloid-ß in neurons, which is a key step in senile plaque formation. Therefore, restoring normal lysosomal function and rebalancing lysosomal acidification in neurons in the brain may be a new treatment strategy for Alzheimer's disease. Microtubule acetylation/deacetylation plays a central role in lysosomal acidification. Here, we show that inhibiting the classic microtubule deacetylase histone deacetylase 6 with an histone deacetylase 6 shRNA or thehistone deacetylase 6 inhibitor valproic acid promoted lysosomal reacidification by modulating V-ATPase assembly in Alzheimer's disease. Furthermore, we found that treatment with valproic acid markedly enhanced autophagy, promoted clearance of amyloid-ß aggregates, and ameliorated cognitive deficits in a mouse model of Alzheimer's disease. Our findings demonstrate a previously unknown neuroprotective mechanism in Alzheimer's disease, in which histone deacetylase 6 inhibition by valproic acid increases V-ATPase assembly and lysosomal acidification.

3.
Adv Mater ; : e2404010, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935245

RESUMO

The imperfect charge behavior at the interfaces of perovskite/electron-transport layer (ETL)/transparent conducting oxide (TCO) limits the further performance improvement of perovskite/silicon tandem solar cells. Herein, an indium tin oxide interlayer is deposited between ETL and TCO to address this issue. Specifically, the interlayer is prepared using an all-physical and H2O-free method, electron-beam evaporation, which can avoid any potential damage to the underlying perovskite and ETL layers. Moreover, the interlayer's composition can be readily tuned by changing the evaporator component, enabling authors to regulate the contact resistance and energy-level alignment of the ETL/TCO interface. Consequently, the resultant perovskite/silicon tandem solar cells exhibit an impressive power conversion efficiency (PCE) of 30.8% (certified 30.3%). Moreover, the device retains 98% of its initial PCE after continuous operation under ambient conditions for 1078 h, representing one of the most stable and efficient perovskite/silicon tandem solar cells.

4.
SLAS Discov ; 29(5): 100160, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38761981

RESUMO

Four years after the beginning of the COVID-19 pandemic, it is important to reflect on the events that have occurred during that time and the knowledge that has been gained. The response to the pandemic was rapid and highly resourced; it was also built upon a foundation of decades of federally funded basic and applied research. Laboratories in government, pharmaceutical, academic, and non-profit institutions all played roles in advancing pre-2020 discoveries to produce clinical treatments. This perspective provides a summary of how the development of high-throughput screening methods in a biosafety level 3 (BSL-3) environment at Southern Research Institute (SR) contributed to pandemic response efforts. The challenges encountered are described, including those of a technical nature as well as those of working under the pressures of an unpredictable virus and pandemic.


Assuntos
COVID-19 , Ensaios de Triagem em Larga Escala , Pandemias , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/virologia , SARS-CoV-2/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Antivirais/uso terapêutico , Antivirais/farmacologia
5.
Poult Sci ; 103(7): 103833, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38810563

RESUMO

The family of cell cycle-dependent kinases (CDKs) serves as catalytic subunits within protein kinase complexes, playing a crucial role in cell cycle progression. While the function of CDK proteins in regulating mammalian innate immune responses and virus replication is well-documented, their role in chickens remains unclear. To address this, we cloned several chicken CDKs, specifically CDK6 through CDK10. We observed that CDK6 is widely expressed across various chicken tissues, with localization in the cytoplasm, nucleus, or both in DF-1 cells. In addition, we also found that multiple chicken CDKs negatively regulate IFN-ß signaling induced by chicken MAVS or chicken STING by targeting different steps. Moreover, during infection with infectious bursal disease virus (IBDV), various chicken CDKs, except CDK10, were recruited and co-localized with viral protein VP1. Interestingly, overexpression of CDK6 in chickens significantly enhanced IBDV replication. Conversely, knocking down CDK6 led to a marked increase in IFN-ß production, triggered by chMDA5. Furthermore, targeting endogenous CDK6 with RNA interference substantially reduced IBDV replication. These findings collectively suggest that chicken CDKs, particularly CDK6, act as suppressors of IFN-ß production and play a facilitative role in IBDV replication.


Assuntos
Proteínas Aviárias , Galinhas , Quinases Ciclina-Dependentes , Replicação Viral , Animais , Galinhas/genética , Proteínas Aviárias/metabolismo , Proteínas Aviárias/genética , Quinases Ciclina-Dependentes/metabolismo , Quinases Ciclina-Dependentes/genética , Vírus da Doença Infecciosa da Bursa/fisiologia , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/genética , Infecções por Birnaviridae/veterinária , Infecções por Birnaviridae/virologia , Imunidade Inata
6.
Sensors (Basel) ; 24(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38793837

RESUMO

A typical magnetometer-based measurement-while-drilling (MWD) system determines the azimuth of the bottom hole assembly during the drilling process by employing triaxial accelerometers and magnetometers. The geomagnetic azimuth solution is susceptible to magnetic interference, especially strong magnetic interference and so a rotary norm constraint filtering (RNCF) method for azimuth estimation, designed to support a gyroscope-aided magnetometer-based MWD system, is proposed. First, a new magnetic dynamical system, one whose output is observed by the magnetometers triad, is designed based on the Coriolis equation of the desired geomagnetic vector. Second, given that the norm of the non-interfered geomagnetic vector can be approximated as a constant during a short-term drilling process, a norm constraint procedure is introduced to the Kalman filter. This is achieved by the normalization of the geomagnetic part of the state vector of the dynamical system and is undertaken in order to obtain a precise geomagnetic component. Simulation and actual drilling experiments show that the proposed RNCF method can effectively improve the azimuth measurement precision with 98.5% over the typical geomagnetic solution and 37.1% over the KF in a RMSE sense when being strong magnetic interference environment.

7.
Drug Des Devel Ther ; 18: 1415-1438, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707614

RESUMO

Objective: This study aims to explore the mechanism of action of Yixintai in treating chronic ischemic heart failure by combining bioinformatics and experimental validation. Materials and Methods: Five potential drugs for treating heart failure were obtained from Yixintai (YXT) through early mass spectrometry detection. The targets of YXT for treating heart failure were obtained by a search of online databases. Gene ontology (GO) functional enrichment analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analyses were conducted on the common targets using the DAVID database. A rat heart failure model was established by ligating the anterior descending branch of the left coronary artery. A small animal color Doppler ultrasound imaging system detected cardiac function indicators. Hematoxylin-eosin (HE), Masson's, and electron microscopy were used to observe the pathological morphology of the myocardium in rats with heart failure. The network pharmacology analysis results were validated by ELISA, qPCR, and Western blotting. Results: A total of 107 effective targets were obtained by combining compound targets and eliminating duplicate values. PPI analysis showed that inflammation-related proteins (TNF and IL1B) were key targets for treating heart failure, and KEGG enrichment suggested that NF-κB signaling pathway was a key pathway for YXT treatment of heart failure. Animal model validation results indicated the following: YXT can significantly reduce the content of intestinal microbiota metabolites such as trimethylamine oxide (TMAO) and improve heart failure by improving the EF and FS values of heart ultrasound in rats and reducing the levels of serum NT-proBNP, ANP, and BNP to improve heart failure. Together, YXT can inhibit cardiac muscle hypertrophy and fibrosis in rats and improve myocardial ultrastructure and serum IL-1ß, IL-6, and TNF-α levels. These effects are achieved by inhibiting the expressions of NF-κB and PKC. Conclusion: YXT regulates the TMAO/PKC/NF-κB signaling pathway in heart failure.


Assuntos
Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Farmacologia em Rede , Transdução de Sinais , Animais , Masculino , Ratos , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Metilaminas/farmacologia , NF-kappa B/metabolismo , Proteína Quinase C/metabolismo , Proteína Quinase C/antagonistas & inibidores , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
8.
Vet Sci ; 11(4)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38668450

RESUMO

This study aimed to identify active miRNA editing sites during adipose development in Ningxiang pigs and analyze their characteristics and functions. Based on small RNA-seq data from the subcutaneous adipose tissues of Ningxiang pigs at four stages-30 days (piglet), 90 days (nursery), 150 days (early fattening), and 210 days (late fattening)-we constructed a developmental map of miRNA editing in the adipose tissues of Ningxiang pigs. A total of 505 miRNA editing sites were identified using the revised pipeline, with C-to-U editing types being the most prevalent, followed by U-to-C, A-to-G, and G-to-U. Importantly, these four types of miRNA editing exhibited base preferences. The number of editing sites showed obvious differences among age groups, with the highest occurrence of miRNA editing events observed at 90 days of age and the lowest at 150 days of age. A total of nine miRNA editing sites were identified in the miRNA seed region, with significant differences in editing levels (p < 0.05) located in ssc-miR-23a, ssc-miR-27a, ssc-miR-30b-5p, ssc-miR-15a, ssc-miR-497, ssc-miR-15b, and ssc-miR-425-5p, respectively. Target gene prediction and KEGG enrichment analyses indicated that the editing of miR-497 might potentially regulate fat deposition by inhibiting adipose synthesis via influencing target binding. These results provide new insights into the regulatory mechanism of pig fat deposition.

9.
Exp Ther Med ; 27(3): 111, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38361523

RESUMO

[This corrects the article DOI: 10.3892/etm.2018.5967.].

10.
Poult Sci ; 103(3): 103344, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38277892

RESUMO

Protein arginine methyltransferase 5 (PRMT5), a type II arginine methyltransferase, controls arginine dimethylation of a variety of substrates. While many papers have reported the function of mammalian PRMT5, it remains unclear how PRMT5 functions in chicken cells. In this study, we found that chicken (ch) PRMT5 is widely expressed in a variety of chicken tissues and is distributed in both the cytoplasm and the nucleus. Ectopic expression of chPRMT5 significantly suppresses chIFN-ß activation induced by chMDA5. In addition, a prmt5 gene-deficient DF-1 cell line was constructed using CRISPR/Cas9. In comparison with the wild-type cells, the prmt5-/- DF-1 cells displays normal morphology and maintain proliferative capacity. Luciferase reporter assay and overexpression showed that prmt5-/- DF-1 cells had increased IFN-ß production. With identified chicken PRMT5 and CRISPR/Cas9 knockout performed in DF-1 cells, we uncovered a functional link of chPRMT5 in suppression of IFN-ß production and interferon-stimulated gene expression.


Assuntos
Galinhas , Interferons , Animais , Interferons/metabolismo , Galinhas/genética , Galinhas/metabolismo , Sistemas CRISPR-Cas , Técnicas de Inativação de Genes/veterinária , Linhagem Celular , Mamíferos/metabolismo
11.
Animals (Basel) ; 13(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37893916

RESUMO

Ningxiang pigs exhibit a diverse array of fatty acids, making them an intriguing model for exploring the genetic underpinnings of fatty acid metabolism. We conducted a genome-wide association study using a dataset comprising 50,697 single-nucleotide polymorphisms (SNPs) and samples from over 600 Ningxiang pigs. Our investigation yielded novel candidate genes linked to five saturated fatty acids (SFAs), four monounsaturated fatty acids (MUFAs), and five polyunsaturated fatty acids (PUFAs). Significant associations with SFAs, MUFAs, and PUFAs were found for 37, 21, and 16 SNPs, respectively. Notably, some SNPs have significant PVE, such as ALGA0047587, which can explain 89.85% variation in Arachidic acid (C20:0); H3GA0046208 and DRGA0016063 can explain a total of 76.76% variation in Elaidic Acid (C18:1n-9(t)), and the significant SNP ALGA0031262 of Arachidonic acid (C20:4n-6) can explain 31.76% of the variation. Several significant SNPs were positioned proximally to previously reported genes. In total, we identified 11 candidate genes (hnRNPU, CEPT1, ATP1B1, DPT, DKK1, PRKG1, EXT2, MEF2C, IL17RA, ITGA1 and ALOX5), six candidate genes (ALOX5AP, MEDAG, ISL1, RXRB, CRY1, and CDKAL1), and five candidate genes (NDUFA4L2, SLC16A7, OTUB1, EIF4E and ROBO2) associated with SFAs, MUFAs, and PUFAs, respectively. These findings hold great promise for advancing breeding strategies aimed at optimizing meat quality and enhancing lipid metabolism within the intramuscular fat (IMF) of Ningxiang pigs.

12.
Materials (Basel) ; 16(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37895701

RESUMO

A microwave transmitter/receiver using the low-temperature co-fired ceramic substrate and ball grid array packaging demonstrates superior properties, including high integration, miniaturization, and high electromagnetic shielding. However, it holds limitations of inadequate hermeticity (that is, gas or moist impermeability), high cost, and low reproducibility. In this work, we aim to overcome these difficulties by introducing a new packing technique. The packaging utilizes an electroless plated Ni/Pd/Au surface, resulting in a significant enhancement of the packaging hermeticity by orders of magnitude, approaching the level of <5 × 10-9 Pa·m3/s. Both Sn63Pb37 and Au80Sn20 solder alloys demonstrate exceptional solderability, attributed to Pd atoms diffusing to the Au layer during soldering at 310 °C. A reliability test of the packaging shows that the shear strength of the solder balls drops after thermal shocks but negligibly affects the hermeticity of the packaging. Furthermore, a meticulously designed internal vertical interconnect structure and I/O interconnections were engineered in the ball grid array packaging, showcasing excellent transmission characteristics within the 10-40 GHz frequency range while ensuring effective isolation between ports.

13.
Innovation (Camb) ; 4(5): 100486, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37636278

RESUMO

The gut microbiota consistently shows strong correlations with lipid metabolism in humans and animals, and whether the gut microbiota contributes to muscle fatty acid (FA) deposition and meat traits in farm animals has not been fully resolved. In this study, we aimed to unveil the microbial mechanisms underlying muscle FA deposition in pigs. First, we systematically revealed the correlation between the gut microbiome and muscle FA levels in 43 obese Ningxiang pigs and 50 lean Duroc Landrace Yorkshire (DLY) pigs. Mutual fecal microbial transplantation showed that the obese Ningxiang pig-derived microbiota increased the muscle FA content and improved meat quality by reshaping the gut microbial composition in lean DLY pigs. Lactobacillus reuteri has been identified as a potential microbial biomarker in obese Ningxiang pig-derived microbiota-challenged DLY pigs. A gavage experiment using lean DLY pigs confirmed that L. reuteri XL0930 isolated from obese Ningxiang pigs was the causal species that increased the muscle FA content. Mechanistically, SLC22A5, a carnitine transporter, was downregulated in L. reuteri XL0930-fed DLY pigs, resulting in reduced muscle carnitine levels. Muscle and intestinal L-carnitine levels, which correlated with the muscle FA content, impeded fat synthesis and FA accumulation in in vitro and in vivo models. In conclusion, we uncovered an unexpected and important role of the obese Ningxiang pig-derived microbiota in regulating muscle FA metabolism via the SLC22A5-mediated carnitine system.

14.
Genes (Basel) ; 14(7)2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37510213

RESUMO

Ningxiang pig is a breed renowned for its exceptional meat quality, but it possesses suboptimal carcass traits. To elucidate the genetic architecture of meat quality and carcass traits in Ningxiang pigs, we assessed heritability and executed a genome-wide association study (GWAS) concerning carcass length, backfat thickness, meat color parameters (L.LD, a.LD, b.LD), and pH at two postmortem intervals (45 min and 24 h) within a Ningxiang pig population. Heritability estimates ranged from moderate to high (0.30~0.80) for carcass traits and from low to high (0.11~0.48) for meat quality traits. We identified 21 significant SNPs, the majority of which were situated within previously documented QTL regions. Furthermore, the GRM4 gene emerged as a pleiotropic gene that correlated with carcass length and backfat thickness. The ADGRF1, FKBP5, and PRIM2 genes were associated with carcass length, while the NIPBL gene was linked to backfat thickness. These genes hold the potential for use in selective breeding programs targeting carcass traits in Ningxiang pigs.


Assuntos
Estudo de Associação Genômica Ampla , Carne , Suínos/genética , Animais , Genótipo , Fenótipo , Carne/análise , Genes cdc
15.
Cell Rep ; 42(7): 112765, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37421622

RESUMO

Plant clock function relies on precise timing of gene expression through complex regulatory networks consisting of activators and repressors at the core of oscillators. Although TIMING OF CAB EXPRESSION 1 (TOC1) has been recognized as a repressor involved in shaping oscillations and regulating clock-driven processes, its potential to directly activate gene expression remains unclear. In this study, we find that OsTOC1 primarily acts as a transcriptional repressor for core clock components, including OsLHY and OsGI. Here, we show that OsTOC1 possesses the ability to directly activate the expression of circadian target genes. Through binding to the promoters of OsTGAL3a/b, transient activation of OsTOC1 induces the expression of OsTGAL3a/b, indicating its role as an activator contributing to pathogen resistance. Moreover, TOC1 participates in regulating multiple yield-related traits in rice. These findings suggest that TOC1's function as a transcriptional repressor is not inherent, providing flexibility to circadian regulations, particularly in outputs.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Relógios Circadianos , Relógios Circadianos/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Regiões Promotoras Genéticas/genética , Regulação da Expressão Gênica de Plantas , Ritmo Circadiano/genética
16.
IEEE Trans Pattern Anal Mach Intell ; 45(11): 13467-13488, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37384469

RESUMO

With the rise of deep convolutional neural networks, object detection has achieved prominent advances in past years. However, such prosperity could not camouflage the unsatisfactory situation of Small Object Detection (SOD), one of the notoriously challenging tasks in computer vision, owing to the poor visual appearance and noisy representation caused by the intrinsic structure of small targets. In addition, large-scale dataset for benchmarking small object detection methods remains a bottleneck. In this paper, we first conduct a thorough review of small object detection. Then, to catalyze the development of SOD, we construct two large-scale Small Object Detection dAtasets (SODA), SODA-D and SODA-A, which focus on the Driving and Aerial scenarios respectively. SODA-D includes 24828 high-quality traffic images and 278433 instances of nine categories. For SODA-A, we harvest 2513 high resolution aerial images and annotate 872069 instances over nine classes. The proposed datasets, as we know, are the first-ever attempt to large-scale benchmarks with a vast collection of exhaustively annotated instances tailored for multi-category SOD. Finally, we evaluate the performance of mainstream methods on SODA. We expect the released benchmarks could facilitate the development of SOD and spawn more breakthroughs in this field.

17.
Biochem Biophys Res Commun ; 673: 145-152, 2023 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-37390747

RESUMO

Myostatin (MSTN) is a major gene target for skeletal muscle overgrowth in animals. We hypothesized that deletion of the entire mature peptide encoded by MSTN in pigs would knock out its bioactive form and accordingly stimulate skeletal muscle overgrowth. Thus, we engineered two pairs of single-guide RNAs (sgRNAs) to target exons 1 and 3 of MSTN in primary fetal fibroblasts of Taoyuan black pigs. We found that sgRNAs targeting exon 3, which encodes the mature peptide, had higher biallelic null mutation efficiency than those targeting exon 1. Somatic cell nuclear transfer was conducted using the exon 3 mutation cells as donor cells to generate five cloned MSTN null piglets (MSTN-/-). Growth testing revealed that both the growth rate and average daily weight gain of MST-/- pigs were greater than those of wild-type (MSTN+/+) pigs. Slaughter data demonstrated that the lean ratio of MSTN-/- pigs was 11.3% higher (P < 0.01) while the back-fat thickness was 17.33% lower (P < 0.01) than those of MSTN+/+ pigs. Haematoxylin-eosin staining indicated that the increased leanness of MSTN-/- pigs resulted from muscle fibre hyperplasia rather than hypertrophy.HE staining showed markedly decreased adipocyte size in MSTN-/- pigs. We also critically examined the off-target and random integration by resequencing, which showed that the founder MSTN-/- pigs contained no non-target mutations or exogenous plasmid elements. This study is the first to report the successful knock out of the mature MSTN peptide using dual sgRNA-mediated deletion, leading to the most prominent alteration of meat production traits in pigs published thus far. This new strategy is expected to have a wide impact on genetic improvements in food animals.


Assuntos
Miostatina , RNA Guia de Sistemas CRISPR-Cas , Animais , Suínos , Técnicas de Inativação de Genes , Miostatina/genética , Hiperplasia/genética , Hiperplasia/patologia , Fibras Musculares Esqueléticas , Músculo Esquelético/patologia , Adipócitos
18.
Sci Data ; 10(1): 319, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37236982

RESUMO

Soil conservation service (SC) is defined as the ability of terrestrial ecosystems to control soil erosion and protect soil function. A long-term and high-resolution estimation of SC is urgent for ecological assessment and land management on a large scale. Here, a 300-m resolution Chinese soil conservation dataset (CSCD) from 1992 to 2019, for the first time, is established based on the Revised Universal Soil Loss Equation (RUSLE) model. The RUSLE modelling was conducted based on five key parameters, including the rainfall erosivity (interpolation of daily rainfall), land cover management (provincial data), conservation practices (weighted by terrain and crop types), topography (30 m), and soil properties (250 m). The dataset agrees with previous measurements in all basins (R2 > 0.5) and other regional simulations. Compared with current studies, the dataset has long-term, large-scale, and relatively high-resolution characteristics. This dataset will serve as a base to open out the mechanism of SC variations in China and could help assess the ecological effects of land management policies.

19.
Nanomicro Lett ; 15(1): 111, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37121964

RESUMO

Wide-bandgap (WBG) perovskite solar cells suffer from severe non-radiative recombination and exhibit relatively large open-circuit voltage (VOC) deficits, limiting their photovoltaic performance. Here, we address these issues by in-situ forming a well-defined 2D perovskite (PMA)2PbCl4 (phenmethylammonium is referred to as PMA) passivation layer on top of the WBG active layer. The 2D layer with highly pure dimensionality and halide components is realized by intentionally tailoring the side-chain substituent at the aryl ring of the post-treatment reagent. First-principle calculation and single-crystal X-ray diffraction results reveal that weak intermolecular interactions between bulky PMA cations and relatively low cation-halide hydrogen bonding strength are crucial in forming the well-defined 2D phase. The (PMA)2PbCl4 forms improved type-I energy level alignment with the WBG perovskite, reducing the electron recombination at the perovskite/hole-transport-layer interface. Applying this strategy in fabricating semi-transparent WBG perovskite solar cells (indium tin oxide as the back electrode), the VOC deficits can be reduced to 0.49 V, comparable with the reported state-of-the-art WBG perovskite solar cells using metal electrodes. Consequently, we obtain hysteresis-free 18.60%-efficient WBG perovskite solar cells with a high VOC of 1.23 V.

20.
Sensors (Basel) ; 22(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36081024

RESUMO

Ku-band drive amplification and a 7-bit true-time-delay (TTD) function were realized as a part of a LTCC-based T/R module to increase integration. The 8-channel T/R module was fabricated and its key characteristics were measured, including a 3-bit (1/2/4 λ) TTD, 4-bit (0.25/0.5/1/2 λ) TTD, receive gain, noise figure and output power. The 8-channel T/R module can be further adopted to increase bandwidth and scanning angle of phased arrays without beam squint.

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