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Interfaces exist between functional layers inside thin film optoelectronic devices, and it is very important to minimize the energy loss when electrons move across the interfaces to improve the photovoltaic performance. For PbS quantum dots (QDs) solar cells with the classical n-i-p device architecture, it is particularly challenging to tune the electron transfer process due to limited material choices for each functional layer. Here, we introduce materials to tune the electron transfer across the three interfaces inside the PbS-QD solar cell: (1) the interface between the ZnO electron transport layer and the n-type iodide capped PbS QD layer (PbS-I QD layer), (2) the interface between the n-type PbS-I layer and the p-type 1,2-ethanedithiol (EDT) treated PbS QD layer (PbS-EDT QD layer), (3) the interface between the PbS-EDT layer and the Au electrode. After passivating the ZnO layer through APTES treating; tuning the band alignment through varying the QD size of PbS -EDT QD layer and a carbazole layer to tune the hole transport process, a power conversion efficiency of 9.23% (V

We study the arithmetic of algebraic varieties defined over number fields by applying Lagrange interpolation to fibrations. Assuming the finiteness of the Tate–Shafarevich group of a certain elliptic curve, we show, for Châtelet surface bundles over curves, that the violation of Hasse principle being accounted for by the Brauer–Manin obstruction is not invariant under an arbitrary finite extension of the ground field.

MoS2 nanosheets (NSs) are novel 2D nanomaterials (NMs) with potential uses in many areas, and therefore oral exposure route to MoS2 NSs is plausible. Currently, MoS2 NSs are considered as biocompatible NMs, but there is lacking of systemic investigations to study the interactions of MoS2 NSs with intestinal cells. In this study, we exposed the 3D Caco-2 spheroids to MoS2 NSs or MoS2 powders (denoted as MoS2-bulk), and investigated the potential adverse effects of MoS2-materials based on transcriptomics and lipidomics analysis. As expected, both MoS2 NSs and MoS2-bulk were dose-dependently internalized into 3D Caco-2 spheroids but did not induce cytotoxicity, membrane disruption or decrease of thiols. However, the Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) analysis indicated that nutrient absorption and metabolism was decreased. One of the most significantly decreased KEGG pathways is fat digestion and absorption (map04975), and Western blotting analysis further showed that fatty acid binding protein 1 and apolipoprotein A1, key proteins involved in fat digestion and absorption, were down-regulated by MoS2 NSs or MoS2-bulk. In addition, BODIPY 493/503 staining suggested that exposure to MoS2 NSs and MoS2-bulk decreased lipid levels in the spheroids. However, lipidomics data indicated that MoS2 materials only decreased 8 lipid classes, including lysophosphatidylcholine, lysodimethylphosphatidylethanolamine, N-acylethanolamine, ceramide phosphoethanolamines, gangliosides, lysosphingomyelin and sulfatide, whereas most of the lipid classes were indeed increased. In addition, MoS2 NSs was more potent to decrease the lipid classes compared with MoS2-bulk. Combined, the results from this study showed that MoS2 NSs and bulk materials were non-cytotoxic but altered lipid profiles in 3D Caco-2 spheroids.

Close-to intrinsic doped MAPbBr3 thick films are depleted and photogenerated carriers drift fast before they get selectively extracted by the electrodes.

Weitong Li,1,* Haiyan Yin,1,* Yulei Song,1 Wenjing Tu,1 Lulu Wang,1 Yongqi Liang,1 Yamei Bai,1,* Guihua Xu2,* 1School of Nursing, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China; 2Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Guihua Xu, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China, Email 7115@njucm.edu.cnBackground: Social isolation is a serious and pervasive health issue among older people, and it is difficult to identify and assess effectively. Based on a thorough and scientific evaluation index system, AHP-Fuzzy comprehensive evaluation could be a valuable technique.Objective: It is crucial to establish interventions that focus on risk factors for the prevention of social isolation in order to give a strong scientific foundation for enhancing older people’s health habits. This can be achieved by using a fuzzy comprehensive evaluation method to assess the risk of social isolation in older people.Methods: A hundred community members over 60 from Nanjing were selected as the evaluation subjects in China. After the element layer was split into three categories of “social risk, economic risk, and cultural risk” using the analytic hierarchy process approach, a total of 22 assessment indicators were picked to develop a risk evaluation index system.Results: The risk level of social isolation belonging to the “low risk, relatively low risk, medium risk, relatively high risk, high risk” of membership degree are respectively “ 0.3392, 0.2632, 0.2257, 0.1069, 0.0650”. Fuzzy comprehensive evaluation analysis showed that social relations (0.4934), monthly income (0.4654), health status (0.5960) were significant factors of social isolation risk in older people. The results showed that factors related to social risk had the most significant impact on social isolation.Conclusion: It is scientific and feasible to construct the risk evaluation index model of social isolation risk for the elderly by using AHP-Fuzzy comprehensive evaluation method. In preventing social isolation of older people in the future, we should pay attention to the impact of social and cultural factors on them, and provide practical intervention programs and references from the government, community, family.Keywords: AHP, fuzzy comprehensive evaluation method, social isolation, older people

To understand the current situation and progress of nursing students' professional self-concept, this review aimed to perform a general analysis of research related to the connotation of professional self-concept, measurement tools, influencing factors, effects, and intervention experiments.Three databases (Web of Science, PubMed, and CNKI) were searched for relevant articles. Research articles that met specific criteria were included, with identified articles initially screened by title and keyword. Then the abstracts were screened for relevance, and the full text was read for validation before inclusion. Descriptive analysis was performed with relevant findings from data retrieved from various sources.Finally, 54 articles that met the criteria were included, which organised the connotation of self-concept of nursing speciality, and introduced six measurement scales, such as Professional Self-Concept of Nurses Instrument and Nurse's Self-Concept Questionnaire. A total of 16 investigations on influencing factors were described, and the results showed that there were internal individual and external environmental factors. The professional self-concept was formed by analysing both factors. This paper described 17 effect surveys and found that professional self-concept had an important impact on students' mental health, academic performance, and professional values, and so on. Eight intervention experiments including attribution training and hierarchical teaching were evaluated.Research articles on the professional self-concept included in this review were rich. These articles clarified the basic connotation of the concept, developed relatively mature measurement tools, found many influencing factors and effects, and proposed effective intervention strategies. They were of great value for understanding the professional self-concept and could provide a reference for scholars to conduct relevant research and practice. It also presents research prospects in this field, aiming to inspire future research.

With the gradual acceleration of population ageing, social isolation in older people has increasingly become a hot topic of social concern. The reduction of valid social participation will cause older people to weaken their sense of belonging to the community and social acquisition, negatively impacting on older people's quality of life. This study is aimed to explore the main related factors affecting the social isolation of older people, so as to provide a solid scientific basis for improving the health behaviour of older people in China.A cross-sectional study was conducted among 2267 community residents over 60 years old from four cites in Jiangsu Province, China. Perceived social support scale, Geriatric Depression Scale, Connor-Davidson Resilience Scale, Comprehensive Ability of Older People Assessment Scale and other influencing factors scales were used to investigate the current situation. Social isolation was measured with the Lubben Social Network Scale. Demographic data were evaluated using descriptive statistical analyses and relationships among study variables were determined to use a path analysis. All data were analyzed using SPSS version 22 and AMOS version 26 using T-test, analysis of variance, logistic regression analyses, and path analysis method. The test level was set at alpha = 0.05, and the difference was statistically significant at P-value0.05.The results of the model test analysis indicated that the hypothesised paths were supported by data from our samples and demonstrated significance on the path coefficients (P 0.05). Related factors in the three dimensions of social risk, economic risk and cultural risk have an impact on the social isolation of older people in the community through direct and indirect pathways, and also indirectly through the partially mediated role of depression. Overall, our hypothesised model was retained, indicating empirical support and adequate model fit indices for the theoretical model.The findings demonstrated the predictive role of related factors of social isolation in older people. In the future, we should focus on developing interventions by uniting many forces such as society, family and older people themselves to reduce social isolation among this vulnerable population and improve the quality of life of older people and promote healthy ageing.

Malus hupehensis is an extensively used apple rootstock in China. In the current study, M. hupehensis seedlings were treated with exogenous 2.2 µm 6-benzyladenine (6-BA) so as to investigate the mechanism by which 6-BA affects lateral root development. The results indicate that 6-BA treatment promotes elongation and thickening of both root and shoot in M. hupehensis, but reduces the number of lateral roots, as well as reducing the auxin level after 6-BA treatment. Moreover, MhAHK4, MhRR1 and MhRR2 were also significantly up-regulated in response to 6-BA treatment. Expression levels of auxin synthesis- and transport-related genes, such as MhYUCCA6, MhYUCCA10, MhPIN1 and MhPIN2, were down-regulated, which corresponds with lower auxin levels in the 6-BA-treated seedlings. A negative regulator of auxin, MhIAA3, was induced by 6-BA treatment, leading to reduced expression of MhARF7 and MhARF19 in 6-BA-treated seedlings. As a result, expression of MhWOX11, MhWOX5, MhLBD16 and MhLBD29 was blocked, which in turn inhibited lateral root initiation. In addition, a lower auxin level decreased expression of MhRR7 and MhRR15, which repressed expression of key transcription factors associated with root development, thus inhibiting lateral root development. In contrast, 6-BA treatment promoted secondary growth (thickening) of the root by inducing expression of MhCYCD3;1 and MhCYCD3;2. Collectively, the changes in hormone levels and gene expression resulted in a reduced number of lateral roots and thicker roots in 6-BA-treated plants.

Consider strong approximation for algebraic varieties defined over a number field k k . Let S S be a finite set of places of k k containing all archimedean places. Let E E be an elliptic curve of positive Mordell–Weil rank and let A A be an abelian variety of positive dimension and of finite Mordell–Weil group. For an arbitrary finite set T \mathfrak {T} of torsion points of E × A E\times A , denote by X X its complement. Supposing the finiteness of ⨿ ⨿ ( E × A ) {\amalg \kern -.25pc\amalg } (E\times A) , we prove that X X satisfies strong approximation with Brauer–Manin obstruction off S S if and only if the projection of T \mathfrak {T} to A A contains no k k -rational points.

Indium (In)-based halide perovskites are desirable for next-generation phosphors and emitting devices, due to their broad emission, nontoxicity, and oxidization avoidance capabilities. However, the...

BACKGROUND With the gradual acceleration of population aging, social isolation in older people has increasingly become a hot topic of social concern. The reduction of valid social participation will cause older people to weaken their sense of belonging to the community and social acquisition, negatively impact on the older people’s quality of life. The study is aimed to explore the main risk factors affecting the social isolation of older people, so as to provide a solid scientific basis for improving the health behavior of older people in China. OBJECTIVE The purpose of the present study is twofold: (i) to describe the prevalence of social isolation and (ii) to identify risk factors that predict social isolation amongst older people living in the community in China. Our study will provide a scientific basis for reducing social isolation and improving the health behavior of older people. METHODS A cross-sectional study was conducted among 2267 community residents over 60 years old from 4 cites in Jiangsu Province, China. Perceived social support scale, Geriatric Depression Scale, Connor-Davidson Resilience Scale, Comprehensive Ability of Older People Assessment Scale and other influencing factors scale were used to investigate the current situation. Social isolation was measured with the Lubben Social Network Scale. Demographic data were evaluated using descriptive statistical analyses and relationships among study variables were determined to use a path analysis. All data were analyzed using SPSS version 22 and AMOS version 26 using T-test, Analysis of Variance (ANOVA), logistic regression analyses, and path analysis method. The test level was set at alpha = 0.05, and the difference was statistically significant at p value < 0.05. RESULTS The results of the model test analysis indicated that the hypothesized paths were supported by data from our samples and demonstrated significance on the path coefficients (p < 0.05). Risk factors in the three dimensions of social risk, economic risk and cultural risk have an impact on the social isolation of older people in the community through direct and indirect pathways, and also indirectly through the partially mediated role of depression. Overall, our hypothesized model was retained, indicating empirical support and adequate model’s fit indices for the theoretical model. CONCLUSIONS The findings demonstrated the predictive role of risk factors of social isolation in older people. In the future, we should focus on developing interventions by uniting many forces such as society, family and older people themselves to reduce social isolation among this vulnerable population and improve the quality of life of older people and promote healthy aging.

This study aims to evaluate the effectiveness and safety of oral Chinese herbal medicine (CHM) in the treatment of knee osteoarthritis (KOA).Systematic review and meta-analysis of randomized controlled trials (RCTs).A computer was used to retrieve all RCTs of CHM in the treatment of KOA from 7 databases (PubMed; Embase; Cochrane Central Register of Controlled Trials; China National Knowledge Infrastructure; Chinese VIP Information Database; Chinese Biomedical Database and Wanfang Med Database) from the establishment to August 2021. The literature was organized using NoteExpress, and literature screening and data extraction were conducted by two researchers independently by the inclusion and exclusion criteria. Quality evaluation was performed using GRADE, and the meta-analysis was performed using RevMan5.4.A total of 31 RCTs and 3115 cases are included. The following meta-analysis results are observed: (1) WOMAC: CHM vs. placebo (SMD = -0.87, 95% CI: -1.27 to -0.47, P0.0001), CHM vs. Western medicine (SMD = -1.64, 95% CI: -2.09 to -1.19, P0.00001), and CHM + Western medicine vs. Western medicine (SMD = -2.17, 95% CI: -3.01 to -1.33, P0.00001); (2) VAS: CHM vs. Western medicine (SMD = -1.02, 95% CI: -1.63 to -0.41, P0.00001) and CHM + Western medicine vs. Western medicine (SMD = -2.68, 95% CI: -4.36 to -1.00, P0.00001); (3) Lequesne severity index: CHM vs. Western medicine (SMD = -0.90, 95% CI: -1.40 to -0.39, P = 0.0005) and CHM + Western medicine vs. Western medicine (SMD = -0.94, 95% CI: -1.36 to -0.52, P0.0001); (4) Lysholm knee joint function score: CHM vs. Western medicine (MD = 9.10, 95% CI: 4.20 to 14.01, P = 0.0003), and CHM + Western medicine vs. Western medicine in a single trial (MD = 21.15, 95% CI: 19.71 to 22.59, P0.00001); (5) SOD: in a single trial, CHM vs. Western medicine (MD = 1.62, 95% CI: 0.9 to 2.30, P0.00001) and CHM + Western medicine vs. Western medicine (MD = 17.08, 95% CI: 10.71 to 23.44, P0.00001); (6) TNF-α: CHM vs. Western medicine (SMD = -1.90, 95% CI: -2.04 to -0.14, P = 0.02) and CHM + Western medicine vs. Western medicine (SMD = -2.32, 95% CI: -4.33 to -0.30, P = 0.02); (7) IL-1β: CHM vs. Western medicine (SMD = -1.60, 95% CI: -2.36 to -0.84, P0.0001); and (8) IL-6: in a single trial, CHM vs. Western medicine (MD = -0.75, 95% CI: -1.20 to -0.30, P = 0.001) and CHM + Western medicine vs. Western medicine (MD = -3.18, 95% CI: -6.24 to -0.12, P = 0.04).The efficacy of CHM in the treatment of KOA is superior to those of placebo and Western medicine. At the same time, the combination of CHM + Western medicine is superior to Western medicine alone in the treatment of KOA. However, due to the existence of certain biases in the included studies, and the need for further study on the effective components of Chinese medicine, a positive conclusion on the efficacy of traditional CHM in the treatment of KOA cannot be drawn and needs to be confirmed by high-quality clinical RCTs.

Composition engineering of halide perovskite allows the tunability of the band gap over a wide range so that photons can be effectively harvested, an aspect that is of critical importance for increasing the efficiency of photocatalysis under sunlight. However, the poor stability and the low photocatalytic activity of halide perovskites prevent use of these defect-tolerant materials in wide applications involving photocatalysis. Here, an alcohol-based photocatalytic system for dye degradation demonstrated high stability through the use of double perovskite of Cs2 AgBiBr6 . The reaction rate on Cs2 AgBiBr6 is comparable to that on CdS, a model inorganic semiconductor photocatalyst. The fact of fast reaction between free radicals and dye molecules indicates the unique catalytic properties of the Cs2 AgBiBr6 surface. Deposition of metal clusters onto Cs2 AgBiBr6 effectively enhances the photocatalytic activity. Although the stability (five consecutive photocatalytic cycles without obvious decrease of efficiency) requires further improvements, the results indicate the significant potential of Cs2 AgBiBr6 -based photocatalysis.

Flexible solar cells represent a unique field in which hybrid perovskites may find complementary application to silicon solar cells. However, significant challenges in the fabrication of electron transport layers and hole transport layers at low temperatures have been imposed for perovskite solar cells since flexible substrates typically cannot withstand high processing temperatures (>150 °C). In this study, a low-temperature (140 °C) processed SnO2 layer was adopted as the electron transport layer in perovskite solar cells on a flexible PEN (polyethylene naphthalate) substrate, and a fullerene derivative with a carboxylic group (CPTA) that modified the interface between SnO2 and MAPbI3 was found to significantly improve the device performance. The beneficial effects of interface modification on increasing the carrier selectivity to electrons were elucidated, which resulted in a power conversion efficiency of 18.36% for the solar cells under simulated AM1.5 sunlight. The flexible solar cell still retained 75% of its initial efficiency after 500 cycles of bending with a curvature radius of 5 mm. The MAPbI3 solar cells were stable under ambient air conditions (25 °C, 30% relative humidity), and 87% of the initial efficiencies were retained for the unencapsulated devices after 46 days of storage in ambient air.

In this paper, bovine serum albumin served as the initial materials for preparing a kind of cyan-emitting fluorescent protein nanoparticles (BSA NPs). The BSA NPs were further adopted as a template to synthesize protein nanoparticles-stabilized silver nanoclusters (BSA NPs@Ag NCs) that offered two well-separated fluorescence emission peaks respectively at 470 nm and 670 nm. Dopamine could specifically induce the fluorescence enhancement at 470 nm and the fluorescence quenching at 670 nm of BSA NPs@Ag NCs. Moreover, cupric ions could cause the fluorescence quenching at 670 nm of BSA NPs@Ag NCs just with a negligible impact on the fluorescence intensity at 470 nm. The BSA NPs@Ag NCs can serve as a ratiometric probe for detection of dopamine and cupric ions.

Bromide-based hybrid perovskites are of particular interest not only due to the fact that they offer a way to go beyond the Shockley–Queisser limit via the tandem cell scheme but single-junction devices of them can also achieve reasonably high efficiency with high stability for solar energy conversion. However, the highest power conversion efficiency achieved up to now for FAPbBr3 single-junction solar cells is only 8.2%, which is far below the efficiency of ∼17% predicted from detailed balance analysis. Here, a two-step method (the intermolecule exchange pathway) was systematically optimized for the fabrication of high-quality FAPbBr3 films. A molecule of urea, structurally similar to formamidinium, is introduced as an additive to tune the intermolecular ion exchange procedure. SnO2 is introduced as an electron-selective contact to the planar structured FAPbBr3 solar cells. As a result, a power conversion efficiency of 10.61% and a Voc of 1.56 V are achieved with planar structured solar cells, both of wh...

RésuméConsidérons l'approximation faible de 0-cycles sur une variété propre lisse définie sur un corps de nombres, elle est conjecturée d'étre contrôlée par le groupe de Brauer de la variété. Soit X une surface de Châtelet ou une compactification lisse d'un espace homogéne d'un groupe algébrique linéaire connexe à stabilisateur connexe. Soit Y une variété rationnellement connexe. Nous montrons que l'approximation faible de 0-cycles sur le produit X × Y est contrôlée par son groupe de Brauer si c'est le cas pour Y après toute extension finie du corps de base. Nous ne supposons l'existence de 0-cycles de degré 1 ni sur X ni sur Y.

In spite of great progress in the surface modification of semiconductor photoelectrodes, the role of the metal oxide cocatalyst on photoelectrochemical (PEC) performance is still not well understood. In this study, ferrihydrite (Fh) as a novel cocatalyst was decorated on a wormlike nanoporous BiVO4 photoanode. A surface kinetics study of Fh/BiVO4 by intensity-modulated photocurrent spectroscopy (IMPS) evidences the primary role of Fh on PEC performance enhancement, varying with the loading of Fh. It was found that dispersed Fh nanoparticles accelerate hole transfer for water oxidation, but the resulting photoanode suffers from poor stability. The thick layers of Fh address the stability of the electrode by suppressing surface charge recombination but result in reduced hole transfer rates. Modification of a BiVO4 film with optimally thick layers of discrete nanoflakes effectively reduces charge recombination without compromising stability, leading to a high AM 1.5 G photocurrent of 4.78 mA/cm2 at 1.23 V ve...

We study the Brauer–Manin obstruction to the Hasse principle and to weak approximation for 0-cycles on algebraic varieties that possess a fibration structure. The issue is to establish the exactness of a local-to-global sequence (E) of Chow groups of 0-cycles. Recently, Harpaz and Wittenberg proved the exactness of (E) for rationally connected fibrations whose smooth fibres verify the exactness of (E) and whose base is either the projective space or a curve verifying the exactness of (E) . In the present paper, we prove the exactness of (E) for fibrations whose bases are Châtelet surfaces or smooth proper models of homogeneous spaces of connected linear algebraic groups with connected stabilizers. We require that either the fibration is valuatively split in codimension 1 and most closed fibres satisfy weak approximation for 0-cycles, or the generic fibre has a 0-cycle of degree 1 and (E) is exact for most fibres.

Pure inorganic perovskite of CsPbI3 attracts great attentions due to its excellent thermal stability and more suitable bandgap for tandem solar cells. The power conversion efficiency (PCE) of CsPbI3 perovskite solar cells has swiftly increased to 19.03%. However, extensive researches on the material property and photovoltaic characterization are rather rare in the literatures. In this study, a remarkable light soaking effect is found in the CsPbI3 based perovskite solar cells as the PCE increases from 10.8% to 18.3% after 180 s soaking under AM 1.5G sunlight. Mechanisms behind this reproducible soaking effect have also been studied. It reveals that the depressed dark current caused by a stronger built-in field and the decreased defects density passivated by the photogenerated electrons result in the enhanced PCE after light soaking. Moreover, we carefully characterize that the supposed “HPbI3” should be “DMAPbI3” synthesized through anti-solvent vapor recrystallisation method.

Maneuvering reentry vehicle (MaRV) model based multiple model algorithm has been tried to track the hypersonic gliding reentry vehicle (HGRV), while there exists a process noise covariance difficulty to modulate. The aerodynamic parameters are assumed to be the first-order Markov processes. The aerodynamic parameter variances of the stochastic reentry ballistic trajectory are prior analyzed, based on which the process noise variances are obtained, and the uniform model set is designed. The target state is estimated with the autonomous multiple-model (AMM) approach, and the expected model augmentation (EMA) is used for a better performance. The HGRV with a constant attack angle and with a type of controlled attack angle are considered, respectively. Simulation results show that the proposed algorithm has a better performance than present algorithms.

Understanding interfacial loss and the ways to improving interfacial property is critical to fabricate highly efficient and reproducible perovskite solar cells (PSCs). In SnO