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Power conversion efficiencies of inverted perovskite solar cells (PSCs) based on methylammonium- and bromide-free formamidinium lead triiodide (FAPbI 3 ) perovskites still lag behind PSCs with a regular configuration. Here we improve the quality of both the bulk and surface of FA 0.98 Cs 0.02 PbI 3 perovskite films to reduce the efficiency gap. First, we use dibutyl sulfoxide, a Lewis base additive, to improve the crystallinity and reduce the defect density and internal residual stress of the perovskite bulk. Then, we treat the surface of the perovskite film with trifluorocarbon-modified phenethylammonium iodide to optimize the energy levels, passivate defects and protect the film against moisture. The inverted PSCs simultaneously achieve 25.1% efficiency (24.5% from the reverse current–voltage scan measured by a third-party institution) and improved stability. The devices maintained 97.4% and 98.2% of their initial power conversion efficiencies after operating under continuous 1-sun air mass 1.5 G illumination for 1,800 h and under damp heat conditions (85 °C and 85% relative humidity) for 1,000 h, respectively. The efficiency and stability of methylammonium- and bromide-free perovskite inverted solar cells need improvement. Now, Chen et al. combine a Lewis-based additive with a fluorocarbon-modified ammonium salt to reduce defects in the perovskite, increasing the device performance.

The long-term stability of perovskite solar cells remains one of the most important challenges for the commercialization of this emerging photovoltaic technology. Here, we adopt a non-noble metal/metal oxide/polymer multiple-barrier to suppress the halide consumption and gaseous perovskite decomposition products release with the chemically inert bismuth electrode and Al 2 O 3 /parylene thin-film encapsulation, as well as the tightly closed system created by the multiple-barrier to jointly suppress the degradation of perovskite solar cells, allowing the corresponding decomposition reactions to reach benign equilibria. The resulting encapsulated formamidinium cesium-based perovskite solar cells with multiple-barrier maintain 90% of their initial efficiencies after continuous operation at 45 °C for 5200 h and 93% of their initial efficiency after continuous operation at 75 °C for 1000 h under 1 sun equivalent white-light LED illumination. The long-term stability of perovskite solar cells remains a critical challenge for the commercialization of the technology. Here, the authors adopt a non-noble metal/metal oxide/polymer multiple-barrier to suppress device degradation, achieving long-term stability in encapsulated p-i-n devices.

Nonsyndromic orofacial cleft (NSOFC) is a severe birth defect that occurs early in embryonic development and includes the subtypes cleft palate only (CPO), cleft lip only (CLO) and cleft lip with cleft palate (CLP). Given a lack of specific genetic factor analysis for CPO and CLO, the present study aimed to dissect the landscape of genetic factors underlying the pathogenesis of these two subtypes using 6,986 cases and 10,165 controls. By combining a genome-wide association study (GWAS) for specific subtypes of CPO and CLO, as well as functional gene network and ontology pathway analysis, we identified 18 genes/loci that surpassed genome-wide significance (P < 5 × 10-8) responsible for NSOFC, including nine for CPO, seven for CLO, two for both conditions and four that contribute to the CLP subtype. Among these 18 genes/loci, 14 are novel and identified in this study and 12 contain developmental transcription factors (TFs), suggesting that TFs are the key factors for the pathogenesis of NSOFC subtypes. Interestingly, we observed an opposite effect of the genetic variants in the IRF6 gene for CPO and CLO. Moreover, the gene expression dosage effect of IRF6 with two different alleles at the same single-nucleotide polymorphism (SNP) plays important roles in driving CPO or CLO. In addition, PAX9 is a key TF for CPO. Our findings define subtypes of NSOFC using genetic factors and their functional ontologies and provide a clue to improve their diagnosis and treatment in the future.

Sedum alfredii is one of a few plant species known to hyperaccumulate cadmium (Cd). Uptake, localization, and tolerance of Cd at cellular levels in shoots were compared in hyperaccumulating (HE) and non-hyperaccumulating (NHE) ecotypes of Sedum alfredii. X-ray fluorescence images of Cd in stems and leaves showed only a slight Cd signal restricted within vascular bundles in the NHEs, while enhanced localization of Cd, with significant tissue- and age-dependent variations, was detected in HEs. In contrast to the vascular-enriched Cd in young stems, parenchyma cells in leaf mesophyll, stem pith and cortex tissues served as terminal storage sites for Cd sequestration in HEs. Kinetics of Cd transport into individual leaf protoplasts of the two ecotypes showed little difference in Cd accumulation. However, far more efficient storage of Cd in vacuoles was apparent in HEs. Subsequent analysis of cell viability and hydrogen peroxide levels suggested that HE protoplasts exhibited higher resistance to Cd than those of NHE protoplasts. These results suggest that efficient sequestration into vacuoles, as opposed to rapid transport into parenchyma cells, is a pivotal process in Cd accumulation and homeostasis in shoots of HE S. alfredii. This is in addition to its efficient root-to-shoot translocation of Cd.

IGBT parallel connections are an effective way to increase the capacity of power electronic converters. The junction temperature balance between IGBTs is one of the key factors in the safe and stable operation of parallel IGBTs system. Therefore, it is very important to study the influence of junction temperature on the power loss of parallel IGBTs system to improve their stability. However, existing research mainly focuses on the loss of a single IGBT or the optimal operating frequency range of parallel IGBTs. It does not involve research on the optimal operating duty cycle range (ODCR) of parallel IGBTs. When IGBT devices work in the positive temperature coefficient range, the on-state loss difference caused by the junction temperature difference and the switching loss difference have different temperature characteristics. Therefore, the concept of the inflection point duty cycle (IPDC) is proposed to evaluate the trend of the junction temperature mismatch between parallel IGBTs. In this paper, an inflection point duty cycle model (IPDCM) is established to analyze the influence of circuit design parameters, IGBT device parameters, and junction temperature differences on the ODCR of parallel IGBTs. Experimental results show that the IPDCM can provide a feasible reference for the reliability, circuit design parameters, and device selection of parallel power devices.

In cascaded H-bridge (CHB) converters, each of the H-bridge carriers of the traditional modulated model predictive control (MPC) is synchronized. Therefore, the steady-state and transient performances are weak in high power applications that exhibit a low switching frequency. The traditional observer-based MPC uses estimation strategies to replace the prediction model under parametric uncertainties. However, there is no effective approach for the uncertainties in the open-loop optimal control law, which leads to a marked decrease in control performance in the presence of high uncertainties. For high power CHB converters, a robust closed-loop MPC using a linear matrix inequality is designed in this study to achieve robust current tracking. The augmented state is asymptotically decreased by the state feedback control law in the terminal elliptical invariant sets. Thus, the worst performance of the model mismatch is minimized. This study also proposes a phase-shifted modulated MPC to improve both the steady-state and transient performances. The voltage of the CHB converter is considered as a whole to implement the proposed method. The optimal duty cycle of each H-bridge, based on the piecewise strategy and voltage-second balanced rule, is implemented by a phase-shifted modulator. Better control performance with shorter response delays, faster tracking speed, and lower overshoot are achieved with a similar switching frequency. The effectiveness of the proposed method is verified by experimental results.

In view of the low sensitivity, high operating temperature and poor selectivity of acetone measurements, in this paper much effort has been paid to improve the performance of acetone sensors from three aspects: increasing the surface area of the material, improving the surface activity and enhancing gas diffusion. A hierarchical flower-like Pt-doped (1 wt %) 3D porous SnO2 (3DPS) material was synthesized by a one-step hydrothermal method. The micropores of the material were constructed by subsequent annealing. The results of the experiments show that the 3DPS-based sensor's response is strongly dependent on temperature, exhibiting a mountain-like response curve. The maximum sensor sensitivity (Ra/Rg) was found to be as high as 505.7 at a heating temperature of 153 °C and with an exposure to 100 ppm acetone. Additionally, at 153 °C, the sensor still had a response of 2.1 when exposed to 50 ppb acetone gas. The 3DPS-based sensor also has an excellent selectivity for acetone detection. The high sensitivity can be explained by the increase in the specific surface area brought about by the hierarchical flower-like structure, the enhanced surface activity of the noble metal nanoparticles, and the rapid diffusion of free-gas and adsorbed gas molecules caused by the multiple channels of the microporous structure.

Background Emerging evidence suggests that circadian rhythms play a role in the regulation of cardiovascular diseases (CVDs). We aim to examine the relationship between the 24-hour behavior rhythms (activity-rest and feeding-fasting rhythms) and stroke. Methods The study included 3201 adult participants with prediabetes/diabetes from the National Health and Nutrition Examination Survey (NHANES) 2011–2014. The 24-hour behavior rhythm indices were calculated using data from accelerometer wearable device and dietary recall for two nonconsecutive days. Six indices were calculated including interdaily stability (IS), intradaily variability (IV), relative amplitude (RA), average activity during the least active continuous 5-hour period (L5), Average activity during the most active continuous 10-hour period (M10) which reflects the activity-rest rhythm, and feeding rhythm score which reflects the feeding-fasting rhythm. These continuous variables were divided into quintiles for logistic regression models. Results Comparing participants in quintile 1, those in quintile 5 of IS and RA exhibited a lower odds of stroke. Conversely, participants in quintile 5 of IV, L5, and L5 start time demonstrated a higher odds of stroke. Furthermore, participants in quintile 5 of feeding rhythm score had a significantly lower odds of stroke. The associations of IV and feeding rhythm score with stroke were more pronounced in participants with diabetes compared to those with prediabetes/diabetes. No significant associations were observed between other 24-hour behavior rhythms and stroke. Conclusions Overall, this study highlights a significant association between 24-hour behavior rhythm and stroke in American adults with prediabetes/diabetes.

In the high-power applications of cascaded H-bridge (CHB) converters, when considering the limitations of the switching characteristics of the power device, the phase-shifted carrier’s pulse width modulation (PSC-PWM) is used to increase the equivalent switching frequency to improve the output quality. However, interleaved carriers make the CHB output characteristics change. Thus, the optimal performance of the traditional fixed switching frequency model predictive control (MPC) using synchronous carrier modulation is no longer applicable. Moreover, it is difficult for the traditional state-space predictive model to quickly eliminate the prediction error caused by a model mismatch in the transient response process. Therefore, parameter mismatch under high uncertainties leads to a significant decrease in the transient optimization performance. In this study, a PSC-PWM modulated MPC is proposed to replace the fixed switching frequency with PSC-PWM and to suppress the parameter mismatching in the predictive model by an adaptive observer. The CHB output voltage is regarded as a whole based on the voltage-second balanced rule within an equivalent switching period to use the adaptive observer. The CHB optimal vector duration calculated by the optimization strategy at each sampling time is implemented by the PSC-PWM within an associated H-bridge carrier period. Excellent dynamic and transient performances of the reference tracking can be obtained by the proposed method at similar carrier frequencies. Finally, the tracking performances are verified by experiments conducted on a 5L-CHB.

Accurately quantifying biological age is crucial for understanding the mechanisms of aging and developing effective interventions. Molecular aging clocks, particularly epigenetic clocks that use DNA methylation data to estimate biological age, have become essential tools in this area of research. However, the lack of a comprehensive, publicly accessible database with uniformly formatted DNA methylation datasets across various ages and tissues complicates the investigation of epigenetic clocks. Researchers face significant challenges in locating relevant datasets, accessing key information from raw data, and managing inconsistent data formats and metadata annotations. Additionally, there is a lack of dedicated resources for aging-related differentially methylated sites (DMSs, also named differentially methylated positions or differentially methylated cytosines) and regions (DMRs), which hinders progress in understanding the epigenetic mechanisms of aging. To address these challenges, we developed MethAgingDB, a comprehensive DNA methylation database for aging biology. MethAgingDB includes 93 datasets, with 11474 profiles from 13 distinct human tissues and 1361 profiles from 9 distinct mouse tissues. The database provides preprocessed DNA methylation data in a consistent matrix format, along with tissue-specific DMSs and DMRs, gene-centric aging insights, and an extensive collection of epigenetic clocks. Together, MethAgingDB is expected to streamline aging-related epigenetic research and support the development of robust, biologically informed aging biomarkers.