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Quantum dot solar cells (QDSCs) are regarded as one of the most efficient devices due to their intermediate band structures. A suitable light-trapping (LT) strategy matching the absorption spectrum is important to improve the photocurrent conversion efficiency of QDSCs. In this paper, we have proposed a design of the periodically patterned top and bottom dielectric nanopyramid arrays for highly efficient light trapping in GaAs-based QDSCs. The dielectric nanopyramid arrays significantly improve the light absorption of QDSCs in the longer wavelength between 0.8 µm and 1.2 µm. In addition, this LT structure ensures a completely flat window layer and back surface field layer while passivating these semiconductor surfaces. For the optimized double-sided structure, the short-circuit current generated by QDSC is 34.32m A/c m 2, where the photocurrent from the quantum dots (QDs) is 5.17m A/c m 2. Compared to the photocurrent of the QDSC without an LT structure, the photocurrent of the double-sided structure is increased by 84%. The QD photocurrent of the double-sided structure is increased by 570% compared to that of the QDSC without the LT structure.
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BACKGROUNDS/AIMS: Pycnogenol (PYC) is a patented mix of bioflavonoids with potent anti-oxidant and anti-inflammatory properties. In this study, we investigated the effects of PYC on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced injury in primary rat astrocytes. METHODS: The primary rat astrocytes were randomly divided into 6 groups, blank control, OGD/R, OGD/R+PYC (10, 20, 40, and 60 µg/mL). The cell activity were detected by MTT and LDH assays, then the levels of oxidant products [malondialdehyde (MDA) and reactive oxygen species (ROS)] , antioxidants [superoxide dismutase (SOD)], mitochondrial membrane potential (MMP) and inflammatory cytokines were detected. In addition, the expression levels of apoptosis-related proteins (Bax, Bcl-2 and Cleaved caspase 3), proinflammatory factors (NF-κB p65), and p-ERK1/2 were measured by Western blot analysis. RESULTS: The results showed that PYC incubation dose-dependently attenuated cell viability loss, LDH leakage, oxidative stress, inflammatory cytokines accumulation and cell apoptosis caused by OGD/R. Furthermore, PYC pretreatment dose-dependently suppressed OGD/R-induced NF-κB p65 nuclear translocation, NF-κB activity and ERK1/2 phosphorylation. Similarly to PYC, NF-κB inhibitor PDTC and ERK1/2 inhibitor PD098059 dramatically inhibited OGD/R-induced NF-κB activation, ERK1/2 phosphorylation, and ROS production, as well as TNF-α secretion. CONCLUSIONS: These findings revealed that PYC has neuroprotective effects against OGD/R-induced injury via NF-κB and ERK1/2 pathways in primary rat astrocytes.
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Astrócitos/efeitos dos fármacos , Flavonoides/farmacologia , Glucose/metabolismo , Sistema de Sinalização das MAP Quinases , NF-kappa B/imunologia , Fármacos Neuroprotetores/farmacologia , Oxigênio/metabolismo , Animais , Astrócitos/imunologia , Astrócitos/metabolismo , Células Cultivadas , Glucose/imunologia , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/imunologia , Extratos Vegetais , Ratos , Ratos Sprague-Dawley , Transdução de SinaisRESUMO
Particles in space cause irradiation damage to the solar cells (SCs), resulting in the degradation of their performance. Quantum dot solar cells (QDSCs) have higher theoretical efficiency and better irradiation resistance than the conventional GaAs SCs, which makes them highly promising for application in space. In this paper, we study the proton irradiation effect on InAs/GaAs0.8Sb0.2 QDSCs by SRIM program. The simulation result shows that the InAs/GaAs0.8Sb0.2 QDSCs have fewer vacancies than GaAs SCs when irradiated with low-energy proton, which indicates that the InAs/GaAs0.8Sb0.2 QDSCs have better anti-irradiation characteristics. The study about displacements per atom and proton concentration in two SCs shows that protons with low energy and high irradiation fluences will cause more serious damage in InAs/GaAs0.8Sb0.2 QDSCs. In addition, the proton incident angle affects the vacancy distribution, while the number of QD layers has little effect on it.
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Quantum dot intermediate band solar cell (QD-IBSC) has high efficiency theoretically. It can absorb photons with energy lower than the bandgap of the semiconductor through the half-filled intermediate band, extending the absorption spectrum of the cell. However, issues in the IBSC, such as the strain around multi-stacking QDs, low thermal excitation energy, and short carrier lifetime, lead to its low conversion efficiency. In recent years, many efforts have been made from different aspects. In this paper, we focus on In(Ga)As QD-IBSC, list the experimental technologies used to improve the performance of the cell and review the recent research progress. By analyzing the effects of different technologies on conversion efficiency, the development direction of the In(Ga)As QD-IBSC in the future is proposed.
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OBJECTIVE: In order to find similarity of the protein X in maize with other species we performed a BLASTP search to identify the maize ZmPR-1 family genes. METHODS: We used a BLASTP search to identify the maize ZmPR-1 family genes that may show similarities between the protein X in maize and other species. RESULTS: A total of 17 ZmPR-1 genes were identified and these genes were unevenly distributed on 8 chromosomes of maize. All ZmPR-1 gene predicted proteins contained a conserved CAP domain, according to the results of multiple sequence alignment and gene structure analysis. Phylogenetic tree analysis of a total of 85 PR-1 protein sequences from maize, sorghum, rice and Arabidopsis showed that the PR-1 family proteins were divided into four categories, and the maize ZmPR-1 was closely related to sorghum PR-1. In the promoter of maize ZmPR-1 gene, hypothetical cis-elements related to fungal induction, defense stress response, plant hormones, low temperature and drought response were detected. Microarray data analysis showed that ZmPR-1 displayed a tissue-specific expression pattern at different developmental stages, and responded to the infections of five maize pathogens. In addition, we further verified that four ZmPR-1 genes (ZmPR-1-5, 12, 14 and 16) were not only significantly up-regulated after Setosphearia turcica infection, but also affected by exogenous cues such as SA, ABA, MeJA and H2O2. CONCLUSION: The ZmPR-1 family may be important in plant disease resistance. This study's data provide important clues for future research on the function of ZmPR-1 family genes.
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BACKGROUND: It was a meta-analysis on the efficacy of statins in the treatment of atherosclerosis. METHODS: The PubMed, Medline, Embase, Web of Sciences, and other Chinese and English databases were used to retrieve literature on randomized controlled trials (RCTs) of statins in the treatment of atherosclerosis, published from January 2000 to January 2021. The Cochrane Handbook for Systematic Reviews of Intervention 5.0.2 was used to conduct bias risk assessment, and Review Manager 5.3 software (RevMan) was used for meta-analysis. RESULTS: A total of 12 articles with 1,180 participants were included in the meta-analysis. In the observation group, the plaque area [mean difference (MD) =-1.21; 95% confidence interval (CI): -2.03 to -0.38; Z =2.87; P=0.004], total cholesterol (TC) level (MD =-0.72; 95% CI: -1.01 to -0.43; Z =4.83; P<0.00001), triglyceride (TG) level (MD =-0.43; 95% CI: -0.76 to -0.09; Z =2.51; P=0.01), and the low-density lipoprotein (LDL-C) level (MD =-0.79; 95% CI: -1.41 to -0.18; Z =2.54; P=0.01) were lower, while the clinical effective rate (MD =3.64; 95% CI: 1.39 to 9.53; Z =2.64; P=0.008) was higher, and the difference was notable. No notable difference was noted in intra-media thickness (IMT) (MD =-0.41; 95% CI: -0.88 to -0.06; Z =1.7; P=0.09), hypersensitive C-reactive protein (hs-CRP) level (MD =-1.61; 95% CI: -3.59 to 0.37; Z =1.7; P=0.09), and high-density lipoprotein (HDL-C) level (MD =0.14; 95% CI: -0.02 to 0.30; Z =2.54; P=0.09) between the 2 groups. DISCUSSION: The use of statins in the treatment of atherosclerosis can reduce the levels of TC, TG, and LDL-C, mitigate clinical symptoms, and reduce blood lipids with good efficacy.
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Aterosclerose , Inibidores de Hidroximetilglutaril-CoA Redutases , Aterosclerose/tratamento farmacológico , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipoproteínas LDL , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
MicroRNAs (miRNAs) have been reported to be involved in many neurodegenerative diseases. The present study focused on the role of hsa-miR-144-3p in one of the neurodegenerative diseases, Parkinson's disease (PD). Our study showed a remarkable down-regulation of miR-144-3p expression in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-treated SH-SY5Y cells. MiR-144-3p was then overexpressed and silenced in human SH-SY5Y cells by miRNA-mimics and miRNA-inhibitor transfections, respectively. Furthermore, ß-amyloid precursor protein (APP) was identified as a target gene of miR-144-3p via a luciferase reporter assay. We found that miR-144-3p overexpression significantly inhibited the protein expression of APP. Since mitochondrial dysfunction has been shown to be one of the major pathological events in PD, we also focused on the role of miR-144-3p and APP in regulating mitochondrial functions. Our study demonstrated that up-regulation of miR-144-3p increased expression of the key genes involved in maintaining mitochondrial function, including peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), nuclear respiratory factor 1 (NRF-1) and mitochondrial transcription factor A (TFAM). Moreover, there was also a significant increase in cellular ATP, cell viability and the relative copy number of mtDNA in the presence of miR-144-3p overexpression. In contrast, miR-144-3p silencing showed opposite effects. We also found that APP overexpression significantly decreased ATP level, cell viability, the relative copy number of mtDNA and the expression of these three genes, which reversed the effects of miR-144-3p overexpression. Taken together, these results show that miR-144-3p plays an important role in maintaining mitochondrial function, and its target gene APP is also involved in this process.
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1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , Precursor de Proteína beta-Amiloide/genética , MicroRNAs/genética , Mitocôndrias/fisiologia , Doença de Parkinson/genética , Precursor de Proteína beta-Amiloide/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA Mitocondrial/genética , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mitocôndrias/genética , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Fator 1 Nuclear Respiratório/metabolismo , Doença de Parkinson/etiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismoRESUMO
Some epidemiological studies have investigated the relationship between genetic polymorphisms of DRD2, COMT, DBH, and MAO-A and migraine susceptibility, but the results are still inconsistent. Thus, our aim was to further assess the association through a meta-analysis.We examined 5 single nucleotide polymorphisms (SNPs) in 4 genes, including DRD2 rs1799732 and rs6275, DBH rs7239728, MAI-A-VNTR, and COMT rs4680, and performed a meta-analysis of 11 published case-control studies including 3138 cases and 4126 controls. Odd ratios (ORs) with 95% confidence intervals (95% CIs) were used to evaluate the association between the 5 genetic polymorphisms and migraine susceptibility.There was no significant relationship between migraine susceptibility and 4 genetic polymorphisms of DRD2 rs1799732 and rs6275, DBH rs7239728, and MAO-A-VNTR. Nevertheless, decreased risk of migraine was observed to be in association with COMT rs4680 polymorphism in overall analysis (AA vs. GG + GA: OR = 0.76, 95% CI = 0.60-0.97, PHet > 0.642, I = 0), and in Caucasian group after subgroup analysis (AA vs. GG + GA: OR = 0.75, 95% CI = 0.58-0.96, PHet > 0.433, I = 0).Studied polymorphisms of DRD2, DBH, and MAO-A genes may not be associated with migraine susceptibility. However, COMT rs4680 polymorphism may decrease the risk of migraine, especially in Caucasians. The failure to evaluate environmental influence and provide adjusted effect size estimates highlights the need for additional studies in a large number to take these factors into consideration, thus better elucidating the role of the genes tested in migraine.
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Catecol O-Metiltransferase/genética , Transtornos de Enxaqueca/genética , Monoaminoxidase/genética , Receptores de Dopamina D2/genética , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo ÚnicoRESUMO
OBJECTIVE: With use of multiplex RT-PCR testing the five RNA viruses associated with viral encephalitis, the aim of research is to find out the epidemiological features of viral encephalitis in Cangzhou of China. METHODS: Patients hospitalized in Cangzhou central hospital with the diagnosis of viral encephalitis from January 2010 to December 2012 were retrospectively analyzed. The sensitivity and specificity of multiplex RT-PCR was compared with ELISA through testing CSF samples of enterovirus (EVs), Japanese encephalitis virus (JEV), mumps virus (MUV), measles virus (MV) and rubella virus (RV). RESULTS: Disease incidence of viral encephalitis in Cangzhou of China was 18.6 per 100 thousand, and the main pathogen focused on EVs, MUV, JEV, MV and RV, which positive rate were 27.8%, 14.4%, 12.2%, 6.7% and 3.3% respectively. The sensitivity and specificity were all higher than ELISA. CONCLUSION: The most common pathogens responsible for viral encephalitis in Cangzhou, Hebei province, China, were EVs, and the multiplex RT-PCR was a rapid, sensitive, accurate method of testing the viruses responsible for causing these illnesses.