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Flexible solar cells have a lot of market potential for application in photovoltaics integrated into buildings and wearable electronics because they are lightweight, shockproof and self-powered. Silicon solar cells have been successfully used in large power plants. However, despite the efforts made for more than 50 years, there has been no notable progress in the development of flexible silicon solar cells because of their rigidity1-4. Here we provide a strategy for fabricating large-scale, foldable silicon wafers and manufacturing flexible solar cells. A textured crystalline silicon wafer always starts to crack at the sharp channels between surface pyramids in the marginal region of the wafer. This fact enabled us to improve the flexibility of silicon wafers by blunting the pyramidal structure in the marginal regions. This edge-blunting technique enables commercial production of large-scale (>240 cm2), high-efficiency (>24%) silicon solar cells that can be rolled similarly to a sheet of paper. The cells retain 100% of their power conversion efficiency after 1,000 side-to-side bending cycles. After being assembled into large (>10,000 cm2) flexible modules, these cells retain 99.62% of their power after thermal cycling between -70 °C and 85 °C for 120 h. Furthermore, they retain 96.03% of their power after 20 min of exposure to air flow when attached to a soft gasbag, which models wind blowing during a violent storm.
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AIMS: To estimate the association between long-term changes in frailty and the risk of incident type 2 diabetes (T2DM) and to evaluate the effect of preventing the worsening of frailty on the risk of T2DM. METHODS: We included 348 205 participants free of baseline T2DM and with frailty phenotype (FP) data from the UK Biobank; among them, 36 175 had at least one follow-up assessment. According to their FP score, participants were grouped into nonfrailty, prefrailty and frailty groups. Frailty assessed at baseline and at follow-up was used to derive the trajectory of frailty (ΔFP). Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: Compared with those in the nonfrailty group at baseline, the HRs of T2DM for the prefrailty and frailty groups were 1.38 (95% CI 1.33-1.43) and 1.69 (95% CI 1.59-1.79), respectively (both p < 0.001), in the multivariable-adjusted model. During a median follow-up of 5.4 years after the final assessment, data for 472 T2DM patients were recorded. A 1-point increase in the final FP was associated with a 25% (95% CI 1.14-1.38; p < 0.001) increased risk of T2DM. For the trajectory of frailty, each 0.5-point/year increase in ΔFP was associated with a 52% (95% CI 1.18-1.97; p < 0.001) greater risk of T2DM, independent of the FP score at baseline. Compared with those that remained in the nonfrailty group, the greatest risk of T2DM over time was prefrailty aggravation (HR 3.03, 95% CI 2.00-4.58; p < 0.001). Using the frailty index did not materially change the results. CONCLUSIONS: Long-term changes in frailty were associated with the risk of incident T2DM, irrespective of baseline frailty status. Preventing the worsening of frailty may reduce T2DM risk.
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Bancos de Espécimes Biológicos , Diabetes Mellitus Tipo 2 , Fragilidade , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Fragilidade/epidemiologia , Feminino , Masculino , Reino Unido/epidemiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Bancos de Espécimes Biológicos/estatística & dados numéricos , Incidência , Fatores de Risco , Seguimentos , Adulto , Modelos de Riscos Proporcionais , Idoso Fragilizado/estatística & dados numéricos , Estudos de Coortes , Biobanco do Reino UnidoRESUMO
The combination of a PD-L1 inhibitor and an anti-angiogenic agent has become the new reference standard in the first-line treatment of non-excisable hepatocellular carcinoma (HCC) due to the survival advantage, but its objective response rate remains low at 36%. Evidence shows that PD-L1 inhibitor resistance is attributed to hypoxic tumor microenvironment. In this study, we performed bioinformatics analysis to identify genes and the underlying mechanisms that improve the efficacy of PD-L1 inhibition. Two public datasets of gene expression profiles, (1) HCC tumor versus adjacent normal tissue (N = 214) and (2) normoxia versus anoxia of HepG2 cells (N = 6), were collected from Gene Expression Omnibus (GEO) database. We identified HCC-signature and hypoxia-related genes, using differential expression analysis, and their 52 overlapping genes. Of these 52 genes, 14 PD-L1 regulator genes were further identified through the multiple regression analysis of TCGA-LIHC dataset (N = 371), and 10 hub genes were indicated in the protein-protein interaction (PPI) network. It was found that POLE2, GABARAPL1, PIK3R1, NDC80, and TPX2 play critical roles in the response and overall survival in cancer patients under PD-L1 inhibitor treatment. Our study provides new insights and potential biomarkers to enhance the immunotherapeutic role of PD-L1 inhibitors in HCC, which can help in exploring new therapeutic strategies.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Antígeno B7-H1/metabolismo , Genes Reguladores , Hipóxia/genética , Biologia Computacional , Microambiente Tumoral/genéticaRESUMO
Background: There is growing interest in the intersection of frailty and heart failure (HF); however, large-sample longitudinal studies in the general population are lacking. Objectives: The goal of this study was to examine the longitudinal relationship between frailty and incident HF, and whether age and genetic predisposition could modify this association. Methods: This prospective cohort study included 340,541 participants (45.7% male; mean age 55.9 ± 8.1 years) free of HF at baseline in the UK Biobank. Frailty was assessed by using the Fried frailty phenotype and included weight loss, exhaustion, low physical activity, slow gait speed, and low grip strength. The weighted polygenetic risk score was calculated. Cox models were used to estimate these associations and the interaction between the 2 factors. Results: During a median 14.1 years of follow-up, 7,590 patients with HF were documented. Compared with nonfrail participants, both prefrail and frail participants had a positive association with the risk of incident HF (prefrail HR: 1.40 [95% CI: 1.17-1.67]; frail HR: 2.07 [95% CI: 1.67-2.57]). Exhaustion (HR: 1.21; 95% CI: 1.03-1.43), slow gait speed (HR: 1.62; 95% CI: 1.39-1.90), and low grip strength (HR: 1.31; 95% CI: 1.14-1.51) were associated with a greater risk of incident HF. Furthermore, genetic susceptibility did not significantly modify the associations (P interaction = 0.094), and the association was significantly strengthened in younger participants (P interaction = 0.008). Conclusions: Frailty status was associated with a higher risk of incident HF independent of genetic risk. A younger population may be more susceptible to HF when exposed to frailty. Whether the modification of frailty status represents another avenue for preventing HF warrants further investigation.
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P-type hydrogenated nanocrystalline silicon (nc-Si:H) has been used as a hole-selective layer for efficient n-type crystalline silicon heterojunction (SHJ) solar cells. However, the presence of an additional valence band offset at the interface between intrinsic amorphous hydrogenated silicon and p-type nc-Si:H films will limit the hole carrier transportation. In this work, it has been found that when a heavily boron-doped silicon oxide layer deposited with high hydrogen dilution to silane (pB) was inserted into their interface, the fill factor of SHJ solar cells increases 3% absolutely because of the reduced valence band offset and the increased opportunity to provide a hopping tunnel assisted by the doping energy level and valence band tail states. Furthermore, the additional boron incorporation in intrinsic amorphous silicon adjacent to pB helps to enhance the built-in electric field, thus increasing the hole selectivity. By these means, the power conversion efficiency was improved from 23.9% to approximately 25%.
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Determining an optimal combination of laser process parameters can significantly improve the efficiency and quality of 40Cr13 steel surface processing. In this study, two machine learning models (ELMSS and ELMPS) were proposed to predict the processing results of surface features to optimize process parameters. The prediction accuracies of the proposed models were always higher than those of traditional back propagation (BP) and radial basis function (RBF) neural networks, and the calculation time of the proposed models was significantly reduced. In comparison, the prediction accuracy ranking for ablation depth was ELMSS (92.6%), BP (89.8%), and RBF (89.6%), and for the ablation width, it was ELMSS (98.3%), BP (97.4%), and RBF (96.1%). The material removal rate was 92.4%, 91.1%, and 89.1% for ELMSS, BP, and RBF, respectively. Finally, the prediction accuracy ranking for surface roughness was 86.8%, 80.7%, and 79.5% for ELMPS, BP, and RBF, respectively. After optimization by the genetic algorithm, the prediction accuracies of the proposed models for the depth, width, material removal rate, and surface roughness reached 94.0%, 99.0%, 93.2%, and 91.2%, respectively. With the support of ELMSS and ELMPS, the results of the surface features can be predicted before machining and the appropriate process parameters can be selected in advance.
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Inorganic photocatalyst-enzyme systems are a prominent platform for the photoreduction of CO2 to value-added chemicals and fuels. However, poor electron transfer kinetics and enzyme deactivation by reactive oxygen species in the photoexcitation process severely limit catalytic efficiency. In chloroplast, enzymatic CO2 reduction and photoexcitation are compartmentalized by the thylakoid membrane, which protects enzymes from photodamage, while the tightly integrated photosystem facilitates electron transfer, promoting photocatalysis. By mimicking this strategy, we constructed a novel functionally compartmental inorganic photocatalyst-enzyme system for CO2 reduction to formate. To accomplish efficient electron transfer, we first synthesized an integrated artificial photosystem by conjugation of the cocatalyst (a Rh complex) onto thiophene-modified C3N4 (TPE-C3N4), demonstrating an NADH regeneration rate of 9.33 µM·min-1, 2.33 times higher than that of a homogeneous counterpart. The enhanced NADH regeneration activity was caused by the tightly conjugated structure of the artificial photosystem, enabling rapid electron transfer from TPE-C3N4 to the Rh complex. To protect formate dehydrogenase (FDH) from photoinduced deactivation, FDH was encapsulated into MAF-7, a metal-organic framework (MOF) material, to compartmentalize FDH from the toxic photoexcitation process, similar to the function of the thylakoid membrane. Moreover, the triazole linkers of MAF-7 possess both hydrophilicity and pH-buffering capacity providing a stable microenvironment for FDH, which could enhance enzyme stability in photosynthesis. The synergy between the enhanced electron transfer of TPE-C3N4 for NADH cofactor regeneration and MOF-protection of the redox enzyme enables the construction of a functionally compartmental inorganic photocatalyst-enzyme association system, promoting CO2 photoconversion to formic acid with a yield of 16.75 mM after 9 h of illumination, 3.24 times greater than that of the homogeneous reaction counterpart.