This work reveals the intrinsic carrier transport behavior of 2D organolead halide perovskites based on phase‐pure homologous (n = 1, 2, and 3) Ruddelsden–Popper perovskite (RPP) (BA)2(MA)n−1PbnI3n+1 ...single crystals. The 2D perovskite field effect transistors with high‐quality exfoliated 2D perovskite bulk crystals are fabricated, and characteristic output and transfer curves are measured from individual single‐crystal flakes with various n values under different temperatures. Unipolar n‐type transport dominated the electrical properties of all these 2D RPP single crystals. The transport behavior of the 2D organolead halide hybrid perovskites exhibits a strong dependence on the n value and the mobility substantially increases as the ratio of the number of inorganic perovskite slabs per organic spacer increases. By extracting the effect of contact resistances, the corrected mobility values for n = 1, 2, and 3 are 2 × 10−3, 8.3 × 10−2, and 1.25 cm2 V−1 s−1 at 77 K, respectively. Furthermore, by combining temperature‐dependent electrical transport and optical measurements, it is found that the origin of the carrier mobility dependence on the phase transition for 2D organolead halide perovskites is very different from that of their 3D counterparts. Our findings offer insight into fundamental carrier transport behavior of 2D organic–inorganic hybrid perovskites based on phase‐pure homologous single crystals.
2D organolead halide perovskite field effect transistors, which are fabricated based on phase‐pure homologous (n = 1, 2, and 3) Ruddelsden–Popper perovskite (BA)2(MA)n−1PbnI3n+1 single crystals are demonstrated. A strong dependence of carrier transport behavior of the 2D organolead halide hybrid perovskites on the n value is revealed.
Organic–inorganic hybrid two-dimensional (2D) perovskites have recently attracted great attention in optical and optoelectronic applications due to their inherent natural quantum-well structure. We ...report the growth of high-quality millimeter-sized single crystals belonging to homologous two-dimensional (2D) hybrid organic–inorganic Ruddelsden–Popper perovskites (RPPs) of (BA)2(MA) n −1Pb n I3 n +1 (n = 1, 2, and 3) by a slow evaporation at a constant-temperature (SECT) solution-growth strategy. The as-grown 2D hybrid perovskite single crystals exhibit excellent crystallinity, phase purity, and spectral uniformity. Low-threshold lasing behaviors with different emission wavelengths at room temperature have been observed from the homologous 2D hybrid RPP single crystals. Our result demonstrates that solution-growth homologous organic–inorganic hybrid 2D perovskite single crystals open up a new window as a promising candidate for optical gain media.
Deeply involved with dyslipidemia, cardiovascular disease has becoming the leading cause of mortality since the early twentieth century in the modern world. Whose correlation with metabolic syndrome ...(MetS), hypertension and type 2 diabetes mellitus (T2DM) has been well established. We conducted a 9-year longitudinal study to identify the association between easily measured lipid parameters, future MetS, hypertension and T2DM by gender and age distribution. Divided into three groups by age (young age: < 40, middle age: ≥ 40 and < 65 and old age: ≥ 65), 7670 participants, receiving standard medical inspection at Tri-Service General Hospital (TSGH) in Taiwan, had been enrolled in this study. Atherogenic index of plasma (AIP) was a logarithmically transformed ratio of triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C). Through multivariate regression analyses, the hazard ratio (HR) of AIP for MetS, hypertension and T2DM were illustrated. AIP revealed significant association with all the aforementioned diseases through the entire three models for both genders. Additionally, AIP revealed significant correlation which remained still after fully adjustment in MetS, hypertension, and T2DM groups for subjects aged 40-64-year-old. Nevertheless, for participants aged above 65-year-old, AIP only demonstrated significant association in MetS group. Our results explore the promising value of AIP to determine the high-risk subjects, especially meddle-aged ones, having MetS, hypertension, and T2DM in the present and the future.
•Landslide modeling use optimized KLR with different kernel functions.•Optimization of factors using FR analysis and multicollinearity analysis.•Comparison of landslide susceptibility maps to reveal ...difference affected by factors.
Globally, but especially in China, landslides are considered to be one of the most severe and significant natural hazards. In this study, bivariate statistical-based kernel logistic regression (KLR) models with different kernel functions (Polynomial, PUK, and Radial Basis Function), named the PLKLR, PUKLR, and RBFKLR models, were proposed for landslide susceptibility evaluation in Zichang City, China. Meanwhile, the present study aims to build landslide susceptibility maps based on bivariate statistical correlation analysis, optimization of different kernel functions, comparison of three landslide susceptibility maps and systematic analysis of spatial patterns. The steps of this article are organized as follows: Firstly, a landslide inventory containing 263 historical landslide locations was constructed. For the purpose of training and validation of models, 263 landslide locations were randomly divided into two parts with a ratio of 70/30. Secondly, 14 landslide conditioning factors were extracted from the spatial database. Subsequently, correlation analysis between the conditioning factors and the occurrence of landslides was conducted using frequency ratios. Then, the conditioning factors with normalized frequency ratios values were used as inputs to build the landslide susceptibility maps using the three models. A multicollinearity analysis was performed using collinearity statistics. Finally, the area under the receiver operating characteristic curve (AUC) was used for comparison and validation of models for recognizing the prediction capability. By further quantitative comparing mapped susceptibility values on a pixel-by-pixel basis, which can acquire underestimations and overestimations of factors (distance to river and slope) and susceptibility area. The results indicated that the PUKLR model had superior performance in landslide susceptibility assessment, with the highest AUC values of 0.884 and 0.766 for training and validation datasets, respectively. This model was followed by the RBFKLR model and the PLKLR model for the training datasets (AUC values of 0.879 and 0.797, respectively), and the PLKLR model and the RBFKLR model for the validation datasets (AUC values of 0.758 and 0.752, respectively). The landslide susceptibility map could help government agencies and decision-makers make wise decisions for future natural hazards prevention in Zichang region.
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•WGSR is an important reaction for H2 production and CO2 capture.•A comprehensive review of the research progress in the WGSR is given.•State-of-the-art thermodynamic and kinetic ...characteristics of the WGSR are underlined.•WGSR behaviors in certain special environments are emphasized.•WGSR in membrane reactors for carbon capture and H2 production is addressed.
The water gas shift reaction is an important and commonly employed reaction in the industry. In the water gas shift reaction, hydrogen is produced from water or steam while carbon monoxide is converted into carbon dioxide. Over the years, on account of the progress in hydrogen energy and carbon capture and storage for developing alternative fuels and mitigating the atmospheric greenhouse effect, the water gas shift reaction has become a crucial route to simultaneously reach the requirements of hydrogen production and carbon dioxide enrichment, thereby enhancing CO2 capture. This article provides a comprehensive review of the research progress in the water gas shift reaction, with particular attention paid to the thermodynamic and kinetic characteristics. The performance of the water gas shift reaction highly depends on the adopted catalysts whose progress in recent years is extensively reviewed. The behaviors of the water gas shift reaction in special environments are also illustrated, several cases have the ability to proceed with water gas shift reaction without any catalyst. The utilization of several separation technologies on the water gas shift reaction such as carbon capture and storage and membrane reactors for purifying hydrogen and enriching carbon dioxide will be addressed as well. Reviewing past studies suggests that separating hydrogen and carbon dioxide in the product gas from the water gas shift reaction can not only increase efficiency but also enhance the usability for further application. The CO conversion is beyond the thermodynamic limitation after applying membrane for the water gas shift reaction.
A turbulent flow can be characterized by Taylor correlation functions which are obtained empirically, understood by statistical mechanics and regarded as universal. Here, we show that Taylor ...correlations are analytically derived by hypothesizing turbulence as a phenomenon of superfluids at resonance. Leveraging from a recent study on heat transfer at the speed of sound, we derived and fitted the longitudinal and lateral turbulent velocities in an isotropic, turbulent flow. The concept of the boundary of the second law helps to specify the integration constants in the solution. From the velocity profiles, Taylor's correlation functions are analytically determined. From the linearity of the eigenfunction, we introduce amplitude and frequency factors. These factors are curve-fitted with two experimental dataset. Additional experimental datasets in the public domain are compared to the correlations, which shows that the theory agrees with experiments very well in isotropic flows. The analytical correlation functions help to elucidate observations that experiments and statistical mechanics have challenges to explain.
Prostate stromal cells play a crucial role in the promotion of tumor growth and immune evasion in the tumor microenvironment (TME) through intricate molecular alterations in their interaction with ...prostate cancer (PCa) cells. While the impact of these cells on establishing an immunosuppressive response and influencing PCa aggressiveness remains incompletely understood. Our study shows that the activation of the leukemia inhibitory factor (LIF)/LIF receptor (LIFR) pathway in both prostate tumor and stromal cells, following androgen deprivation therapy (ADT), leads to the development of an immunosuppressive TME. Activation of LIF/LIFR signaling in PCa cells induces neuroendocrine differentiation (NED) and upregulates immune checkpoint expression. Inhibition of LIF/LIFR attenuates these effects, underscoring the crucial role of LIF/LIFR in linking NED to immunosuppression. Prostate stromal cells expressing LIFR contribute to NED and immunosuppressive marker abundance in PCa cells, while LIFR knockdown in prostate stromal cells reverses these effects. ADT‐driven LIF/LIFR signaling induces brain‐derived neurotrophic factor (BDNF) expression, which, in turn, promotes NED, aggressiveness, and immune evasion in PCa cells. Clinical analyses demonstrate elevated BDNF levels in metastatic castration‐resistant PCa (CRPC) and a positive correlation with programmed death‐ligand 1 (PDL1) and immunosuppressive signatures. This study shows that the crosstalk between PCa cells and prostate stromal cells enhances LIF/LIFR signaling, contributing to an immunosuppressive TME and NED in PCa cells through the upregulation of BDNF.
Activation of LIF/LIFR/STAT3 signaling in the prostate cancer tumor microenvironment triggers BDNF production, linked to heightened PDL1 expression and neuroendocrine differentiation in prostate cancer cells. This pathway is crucial in stromal cells for regulating immune suppression and checkpoint responses, suggesting potential prognostic markers and therapies to combat immune evasion and neuroendocrine differentiation in prostate cancer.
Lockdown is an effective nonpharmaceutical intervention to reduce coronavirus disease 2019 (COVID-19) transmission, but it restricts daily activity. We aimed to investigate the impact of lockdown on ...pediatric body weight and body mass index (BMI).
The systematic review and meta-analysis were conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement. Four online databases (EMBASE, Medline, the Cochrane Library and CINAHL) were searched.
The pooled results showed that lockdown was associated with significant body weight gain (MD 2.67, 95% CI 2.12-3.23;
< 0.00001). The BMI of children with comorbidities or obesity did not change significantly. The BMI of general population was significantly higher during lockdown than before the pandemic (MD 0.94, 95% CI 0.32-1.56;
= 0.003). However, heterogeneity was high (I
= 84%). Among changes in weight classification, increases in the rates of obesity (OR 1.23, 95% CI 1.10-1.37;
= 0.0002) and overweight (OR 1.17, 95% CI 1.06-1.29;
= 0.001) were reported.
Our meta-analysis showed significant increases in body weight and BMI during lockdown among school-age children and adolescents. The prevalence of obesity and overweight also increased. The COVID-19 pandemic worsened the burden of childhood obesity.
Photodetectors based on reduced graphene oxide (rGO) have attracted much attention owing to their simple and low‐cost fabrication process. However, the aggregation and defects of rGO flakes still ...limit the performance of rGO photodetectors. Controlling the composition of rGO has become a vital factor for its prospective applications. For example, the interconnection between rGO and polymers for modified morphologies of rGO films leads to an enhanced performance of devices. In this work, a practical approach to engineer surface uniformity and enhance the performance of a photodetector by modifying the rGO film with hydrophilic polymers poly(vinyl alcohol) (PVA) is reported. Compared with the rGO photodetector, the on/off ratio for the PVA/rGO photodetector shows 3.5 times improvement, and the detectivity shows 53% enhancement even when the photodetector is operated at a low bias of 0.3 V. This study provides an effective route to realize PVA/rGO photodetectors with a low‐power operation which shows promising opportunities for the future development of green systems.
A practical approach to enhance the performance of a reduced graphene oxide (rGO) photodetector by modifying the rGO film with poly(vinyl alcohol) (PVA) is reported. Compared with the rGO photodetector, the on/off ratio for the PVA/rGO photodetector shows 3.5 times improvement, and the detectivity shows 53% enhancement at a low operating bias of 0.3 V.
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