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Compound/silicon heterojunction (SCH) solar cells have been widely studied due to the low parasitic absorption of the window layer, high short-circuit current, and simple preparation process. So far, most reported SCH solar cells are small-area devices. By depositing MoO hole transport layer using hot-wire oxidation-sublimation deposition technique and employing a front-contact back-junction cell architecture, the large-area SCH solar cells are successfully fabricated on M6 (166 mm) n-type silicon wafers. Indium cerium oxide (ICO) film with the optimal thickness of about 110 nm is inserted between MoO and Ag. The ICO/Ag stack functions well as a back reflector and is beneficial for increasing the short-circuit current density, reducing the contact resistance, and improving the device stability. A power conversion efficiency of 21.59% is achieved on the champion SCH solar cell with the device area of 274.15 cm .

The relations between carbon and oil market is concerned by many scholars but little research has focused on the dependence between their quantiles. We use Quantile on Quantile Regression method to study the impact of WTI crude oil price and Daqing crude oil price on carbon price and use wavelet analysis to clean and decompose the time series. Results show that the impact of crude oil on carbon is heterogeneous. Research based on the original sequence shows that crude oil price has a positive impact on carbon price at all quantile levels. Research based on decomposition sequence shows that the positive impact of crude oil on carbon begins to weaken, the zero effect begins to increase, and the negative impact also begins to appear. However, the negative impact on carbon price becomes stronger with the stability of the time series data obtained from the decomposition of crude oil price series gradually improving, while the positive impact gradually weakens.

A modification strategy of the SnO2ETLs by incorporating an organic ammonium chloride salt, PACl, to the commercial SnO2colloidal solution is presented. A PCE up to 22.27% is achieved on the n-i-p planar PSCs based on the PACl incorporated SnO2ETLs.

In this work, high quality hafnium and hydrogen co-doped In O (IHfO:H) transparent conductive films are developed via a reactive plasma deposition (RPD) technique followed by air atmosphere annealing. Crystallinity, valence states, and opto-electronic properties of the IHfO:H films under different H concentration (0-1.5 %) and different annealing temperature (100-250 °C) are systematically investigated. The effects of hydrogen doping and annealing temperature on the properties of the IHfO:H films are discussed. The high average transmittances (400-800 nm: 87.92 %; 800-2300 nm: 86.68 %), a sheet resistance of 27.53 Ω/□, and a Hall mobility of 102.92 cm V s are achieved on the optimized IHfO:H thin film fabricated using 0.8 % H concentration with a 200 °C annealing temperature. Finally, the IHfO:H films are applied to the bifacial silicon heterojunction (SHJ) solar cells to serve as the front-side transparent electrode. The significant improvement in the long wavelength spectral response compared to the control SHJ device with an indium tin oxide (ITO) front-side transparent electrode leads to an increase of about 0.3 % in the efficiency and an efficiency of over 25 % is achieved on the SHJ solar cell with an IHfO:H front-side transparent electrode.

Poly(3,4-ethylenedioxythiophene) mixed with poly (styrenesulfonate) (PEDOT:PSS) is considered as one of the most valuable conductive polymers due to its high conductivity, transparency and mechanical flexibility. Many experiments have proved that H2SO4 post-treatment is an effective way to enhance the electrical conductivity of PEDOT:PSS films. Here we reported a method for the fabrication of PEDOT:PSS films with conductivity as high as 6323.9 ± 364.5 S/cm, based on a two-step H2SO4 post-treatment. This very high conductivity is, as far as we know, the highest reported value for PEDOT:PSS films by solution preparation. The removal of PSS and redox reaction are the keys to enhance the conductivity of PEDOT:PSS films.

In the context of the increasing global economic policy uncertainty (EPU) and the gradual reduction of US Treasuries holdings in many countries, based on the ADCC-GARCH model and sensitivity analysis, we find that the relative increase of instability in the global economic system will affect foreign investors’ decision-making of investing in the US Treasuries, especially during the high uncertainty period. Shocks in global uncertainty significantly and negatively explain most samples’ time-varying correlations with a lag of one or two months. To some extent, the sustainability and investors’ inherent understanding of US Treasuries’ safety has been shaken in the recent years. Our findings hold important implications for both foreign investors and financial advisors who are interested in US Treasuries.

BackgroundCesarean scar pregnancy (CSP) is a rare and new form of ectopic pregnancy. With increasing rate of cesarean delivery worldwide during the decades, the incidence of CSP increases as well. It may cause massive hemorrhage, uterine rupture, placenta percreta, hysterectomy or even maternal death. This study is to compare the efficacy of high-intensity focused ultrasound (HIFU) and uterine artery embolization (UAE) associated with ultrasound-guided dilatation and curettage (UGDC) in three types of CSP. Methods403 CSP patients were treated with UGDC after pretreatment. Among them, 288 patients chose HIFU before UGDC, while the others (n=115) chose UAE. The body mass index (BMI), gravidity, parity, the number of cesarean delivery, the interval of previous cesarean delivery (PCD), the length, thickness and width of uterus and gestational sac, fetal cardiac activity, the types of CSP, the baseline of beta-human chorionic gonadotropin (β-HCG), the value of β-HCG before and 24 hours after pretreatment, hospital expenditure, the value of hemoglobin before and 24 hours after dilatation and curettage (D&C) and severe complications were collected and compared between the two groups. ResultsAll patients were successfully treated without severe complications. There was no significant difference in maternal age, BMI, gravidity, parity, the number of cesarean delivery, the interval of PCD, the volume of uterus and gestational sac, fetal heart activity, types of CSP and baseline serum β-HCG level between the two groups. The median hospital expenditure and blood loss were less in HIFU group and the median decline rate of β-HCG was higher in HIFU group (p=0.000, p=0.000, p=0.006, respectively). 39 (13.54%) patients in HIFU group, while 21 (18.26%) cases in UAE group used Foley balloon to control the vaginal bleeding.ConclusionBoth HIFU and UAE combined with UGDC have high successful rate in the treatment of CSP. While, HIFU followed by UGDC might be better for less hospital expenditure, blood loss and higher decline rate of β-HCG.

In the evaluation of the druggability of candidate compounds, it was vital to predict the oral bioavailability of compounds from apparent permeability (Papp) across Caco-2 cell-culture model of intestinal epithelium cultured on commercial transwell plate inserts. The study was to investigate the transport characteristics and permeability of FL118 (10, 11-Methylenedioxy-20(S)-camptothecin) derivatives 7-Q6 (7-(4-Ethylphenyl)-10, 11-methylenedioxy-20(S)-camptothecin) and 7-Q20 (7-(4-Trifluoromethylphenyl)-10, 11-methylenedioxy-20(S)-camptothecin). Transport characteristics and permeability of the tested compounds to the small intestine were assessed at different concentrations (0.5, 1 µM) via Caco-2 cell monolayers model in vitro. Uptake studies based on Caco-2 cells, including temperatures, concentrations, and the influence of efflux transporters, were combined to confirm the transport characteristics of the tested compounds. Furthermore, cytotoxicity results showed that the concentrations used in the experiments were non-toxic and harmless to cells. In addition, The Papp of 7-Q6 was (3.69 ± 1.07) × 10-6 cm/s with efflux ratio (ER) 0.98, while the Papp of 7-Q20 was (7.78 ± 0.89) × 10-6 cm/s with ER 1.05 for apical-to-basolateral (AP→BL) at 0.5 µM, suggesting that 7-Q20 might possess higher oral bioavailability in vivo. Furthermore, P-glycoprotein (P-gp) was proved to slightly affect the accumulations of 7-Q20, while the absorption of 7-Q6 was irrelevant with P-gp and breast cancer resistant protein (BCRP) based on the cellular uptake assays. Accordingly, 7-Q6 was completely absorbed by passive diffusion, and 7-Q20 was mainly dependent on passive diffusion with being effluxed by P-gp slightly. Meanwhile, both 7-Q6 and 7-Q20 were potential antitumor drugs that might exhibit high oral bioavailability in the body.

Combining the spillover index approach and LASSO-VAR method, we construct the spillover network of 19 specific countries' economic policy uncertainty (EPU). Then we deconstruct the constructed network into four blocks by the block models, the impacts of COVID-19 on EPU spillover effects between each country and blocks is analyzed gradually. The results reveal that: (1) The transnational contagion of EPU is significant, and the spillover network of policy uncertainty is time-varying. (2) EPU networks can be divided into four different blocks by block models. The role of blocks and the spatial spillover transmission path between blocks are different in different periods. (3) The new infection cases and deaths of COVID-19 have a significant effect on reception and transmission directional EPU spillovers, while there is no significant impact on net spillovers. The international movement restrictions during the period of COVID-19 significantly increase the directional and net EPU spillovers. Our findings have some implications for policy-makers and market regulators in the context of the COVID-19 pandemic.

Small and medium-sized enterprises have been the driving force of social economy. As the social formation and the rise of many emerging economies, the domestic economic environment changes dramatically, which makes small and medium-sized enterprises face severe challenges. In the face of the fierce competition environment, how to improve the performance of entrepreneurship and gain competitive advantage is a very important topic in the practical management of entrepreneurs. This exploration is carried out with the entrepreneurial passion and risk taking as the antecedent variable, entrepreneurial performance as the outcome variable, and then work engagement as the mediator. With the entrepreneurs of small and medium-sized enterprises as the research object, questionnaire method is used to carry out empirical research. The empirical analysis results show that entrepreneurial passion has a significant positive impact on work engagement; risk taking has a significant positive impact on work engagement; work engagement has a significant positive impact on entrepreneurship performance; in addition, work participation plays a mediating role in the process of entrepreneurial passion and risk taking. The results provide academic and practical implications for entrepreneurs.

Drug uptake and efflux are two of the critical factors required in order to be able to define drug efficacy. This study aims to investigate cytotoxicity and uptake mechanisms of two FL118 analogues (7-Q20 and val-FL118) in parallel with FL118 in three-dimensional multi-cellular spheroids model. The influence of compound concentration, time, temperature, cell lines, and the inhibitors of P-gp, BCRP and LAT1 on drug uptake and efflux were investigated. In vitro cytotoxicity studies revealed that FL118, 7-Q20 and val-FL118 exhibited sensitive cytotoxicity to the HCT-116 cell line and the water-soluble compound 7-Q20 showed the lowest IC(50). Cellular uptake and efflux of FL118 was independent of efflux pump proteins. Uptake and efflux of 7-Q20 were affected by P-gp, which was one of reasons that caused a lower uptake at 37 °C than at 4 °C. The carrier protein LAT1 played a role in the cellular intakes of val-FL118. These findings provided basic information for FL118 and the two novel FL118 derivatives for further development.

Water quality mechanism modeling and eutrophication analysis are important technical means for water pollution prevention and control of lake and reservoirs. However, the existing classical water quality mechanism models usually contain unknown parameters with empirical values range, which brings difficulty of predicting water quality changes of specific lakes and reservoirs to meet the accuracy requirements. Furthermore, the most existing water quality prediction methods output single-valued predictions of water quality indicators. These prediction results possess contingencies and uncertainties. Eutrophication analysis based on these results will bring errors, even become completely wrong. Therefore, combining the evolution mechanism of water quality, this paper proposes a fruit fly optimization algorithm (FFOA)-based water quality mechanism modeling method and studies a eutrophication risk assessment method of lakes and reservoirs based on the mechanism model. First, combining observed water quality data, unknown parameters of a water quality mechanism model are estimated by using FFOA. Then, Monte Carlo simulation is employed to predict the evolution of water quality, and the probability distribution functions (PDFs) of water quality indicators at predicted time indexes are obtained to achieve water quality prediction. Finally, to quantitatively assess the eutrophication status, a comprehensive eutrophication status index (CESI) is constructed. The PDF of CESI and the probabilities of being in different eutrophication levels are calculated to achieve water eutrophication risk assessment. The simulation results show that the proposed method can effectively estimate the unknown parameters of the water quality mechanism model, predict water quality evolution and assess the eutrophication risk with better accuracy and rationality by comparing the existing methods.

Gabosines and their natural analogues, belonging to C7 carbasugars, have attracted great attention in synthesis due to their rich structural variety and promising biological activities. A new diversity-oriented approach for the gabosine-type carbasugars based on a tunable regioselective aldol cyclization of flexible precursor 2 is explored. Two cyclization modes (A and B) of the precursor can be well controlled by switching promoters to selectively produce two resulting cyclohexa(e)nones 3 and 10, both of which are versatile intermediates for various C7 carbasugars. After the conversion of 3 to eight natural carbasugars, the utility of intermediate 10 is illustrated by the first synthesis of (-)-gabosine L, as well as the new synthesis of (-)-gabosine A, (-)-gabosine B, (-)-gabosine N and (-)-gabosine O. The chemical structure and the absolute configuration of (-)-gabosine L are confirmed by its total synthesis.

Active disturbance rejection control (ADRC) is a kind of effective tool in dealing with dynamic instability, simultaneous internal and external disturbances, nonlinearity, etc. However, the application of ADRC is limited because the input and output signals of the system are not synchronized due to the existence of time-delay impact in a time-delay system. Modified twice optimal control (MTOC) is a control algorithm proposed for the time-delay system. It can effectively compensate the time-delay impact, synchronize the input and output signals of the system, and provide control conditions for a better application of ADRC to system control. In this paper, a new control algorithm, namely active disturbance rejection modified twice optimal control (ADRMTOC), is proposed based on the suppression capability of ADRC to system total disturbance and the compensation ability of MTOC to time-delay impact. The simulation experiments show that the system under this control method has strong robustness and interference suppression ability, which makes ADRMTOC have certain industrial practical values.

Hybrid heterojunction solar cells (HHSCs) using crystalline Si nanowires (SiNWs) as the absorber and conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as the hole-selective transport layer (HTL) show great potential in both low-cost and high-power conversion efficiency (PCE). However, due to the poor wettability of the PEDOT:PSS solution on SiNWs, conformal coverage of PEDOT:PSS on SiNWs is not easy to achieve. Here, an effective method was developed to decrease the surface tension of the PEDOT:PSS and increase the wettability between PEDOT:PSS and SiNWs by incorporating organosilane into the PEDOT:PSS solution. Two kinds of organosilanes including tetramethoxysilane (TMOS) and vinyltrimethoxysilane (VTMO) were selected as the additives. The surface passivation quality of the SiNWs was dramatically enhanced. The HHSCs utilizing VTMO as the additive show a higher open circuit voltage and higher PCE compared with the TMOS adding ones. By spin-coating Ag nanowires onto the PEDOT:PSS HTL layer and using spin-coated phenyl-C61-butyric acid methyl ester as the electron-selective transport layer, a champion PCE up to 18.12% and a fill factor of 80.1% have been achieved on the full solution processed PEDOT:PSS/n-type SiNWs HHSCs. The findings provide a simple and promising method to achieve high-performance PEDOT:PSS/SiNWs HHSCs.

Poly (3, 4 – ethylenedioxythiophene) – poly (styrenesulfonate) (PEDOT: PSS) thin film has caught much attention because of its high electrical conductivity, optical transmittance and mechanical flexibility. Reducing the PSS content can improve the conductivity of PEDOT: PSS film effectively. However, few studies have been reported on the corresponding degradation behaviors and mechanisms for the PEDOT: PSS films with different PSS contents. Here, we studied the degradation phenomena under various aging conditions. Our results indicated that the degradation behaviors are determined by the content of PSS, and the degradation mechanism is related to the change of molecular configuration of PEDOT chains under various aging conditions.

Silicon/organic hybrid solar cells, with relatively simple and low-energy consumption fabrication processes, hold the promise for over-all cost reduction. However, their performances are still not comparable to the commercial crystalline silicon (c-Si) solar cells. Here, hybrid devices with organic phenyl-C61-butyric acid methyl ester (PCBM) layer inserted between metal electrode and textured p-type crystalline silicon (c-Si(p)) substrate are investigated. The quality of the PCBM/c-Si(p) contact is much improved after a SiOx thin layer is formed on the a-Si:H(i) surface and a Voc of 706 mV and an efficiency of 20.0% are achieved on the hybrid solar cells. Analysis of the dark J-V-T characteristics of the hybrid device shows that the junction current is dominated by the minority-carrier diffusion current.