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The performance of perovskite cells closely relies on the quality of films, leading to a special focus on crystallization manipulation and defect control. In this study, a novel approach using 1D metal‐free perovskites, specifically DABCO‐NH4Cl3, is proposed to facilitate the crystallization process of 3D FAPbI3 perovskites, while simultaneously addressing surface defects. Analysis of crystallization kinetics reveals that the introduction of 1D metal‐free perovskites provides numerous nucleation sites, effectively slowing down crystal growth rates and resulting in the formation of uniform, large‐grain perovskite films. Furthermore, the organic groups present in 1D perovskites play a crucial role in passivating defects within the perovskite structure. The synergistic impact of these factors enables the perovskite to achieve an efficiency of 24.72% while demonstrating exceptional stability. This research offers a promising approach for controlling perovskite crystallization, leading to the development of high‐efficiency and stable perovskite materials. [ABSTRACT FROM AUTHOR]

Forest fires are a primary driver of biogeochemical processes in ecosystems and affect the soil nutrient balance by altering the distribution of organic matter and associated nutrients as well as the composition and availability of elemental nutrients. We investigated the changes in soils' phosphorus (P) fractions and the adsorption characteristics of potassium dihydrogen orthophosphate (orthoP) and myo‐inositol hexakisphosphate (IHP) at two depths (0–5 and 5–10 cm) in soils from two sites differing in fire severity: long‐unburned and heavily burned. Five years after the fire, there were increases in the total P and extractable inorganic P (H2O‐P, NaHCO3‐Pi, NaOH‐Pi, D.HCl‐Pi and C.HCl‐Pi) contents. Conversely, there was a decrease in organic P (NaHCO3‐Po, NaOH‐Po and C.HCl‐Po). The adsorption of soil for orthoP at a depth of 0–5 cm was dependent on the amount of P supplied by the soil; at low concentrations, heavily burned soil showed a lower adsorption than long‐unburned soil. However, at high concentrations, the adsorption of heavily burned soil was significantly larger than that of long‐unburned soil. With respect to IHP, the adsorption of long‐unburned soil was also more significant at depths of 0–5 cm. The adsorption of both orthoP and IHP of heavily burned soil was significantly higher than that of long‐unburned soil at a depth of 5–10 cm. Fire also decreased the binding degree (k1) of soil‐P and the solid phase at depths of 0–5 and 5–10 cm. The increase in P adsorption capacity outweighed the addition of P from ash, resulting in less leaching in heavily burned areas and minimizing P loss. Overall, forest fires significantly affect the adsorption characteristics and P fractions of soil, specifically orthoP and IHP, during the initial stage of postfire recovery. These effects are closely related to the direct influences of iron oxide, soil organic matter and aluminium oxide in the soil and may even produce relatively long‐term effects on the P recycling process of the entire ecosystem. [ABSTRACT FROM AUTHOR]

Problem‐oriented teaching (POT) activities are important in classroom instruction. The level of student response can be influenced by different teacher behaviours in POT. However, the characteristics of teachers' multimodal behaviours at different levels of response are unclear. This study applied epistemic network analysis to explore the characteristics of teachers' multimodal behaviours in POT with different response levels. Using 256 POT segments from 12 classroom teaching videos in primary and secondary schools, this study found that authentic questions and iconic gestures occupied a central position in multimodal behaviours. The concomitant use of multimodal behaviours and the flexibility in eye contact could improve the response levels of students. These findings help understand how teachers' multimodal behaviours can promote students' responses. Practitioner notesWhat is already known about this topic Various behaviours have been shown to impact learners' response, such as teachers' responses to students and teachers' non‐verbal behaviours.Epistemic network analysis can be used to analyse the structure of the connections between cognitive, social and interaction data.What this paper adds This study analyses the characteristics of teachers' multimodal behaviours during problem‐oriented activities.It also compares the salient properties of non‐verbal, verbal and multimodal behavioural networks generated by interactive fragments of students' responses of different cognitive levels.Implications for practice and policy Teachers should ask more authentic questions in the classroom to promote in‐depth thinking processes in students.The appropriate coordination of multimodal behaviours by teachers is crucial to promote the cognitive level of students' responses.Upon making eye contact with students, teachers should also use iconic gestures and be flexible regarding the use of eye contact. [ABSTRACT FROM AUTHOR]

The perovskite layer contains a large number of charged defects that seriously impair the efficiency and stability of perovskite solar cells (PSCs), thus it is essential to develop an effective passivation strategy to heal them. Based on theoretical calculations, it is found that enhancing the electrostatic potential of passivators can improve passivation effect and adsorption energy between charged defects and passivators. Herein, an electrostatic potential modulation (EPM) strategy is developed to design passivators for highly efficient and stable PSCs. With the EPM strategy, 1‐phenylethylbiguanide (PEBG) and 1‐phenylbiguanide (PBG) are designed. It is found that the charge distribution and electrostatic potential of phenyl‐ and phenylethyl‐ substituent on the biguanide are significantly enhanced. The N atom directly bonding to the phenyl group shows larger positive charge than that bonding to the phenylethyl group. The modulated electrostatic potential makes PBG bind stronger with the defects on perovskite surface. Based on the effective passivation of EPM, a champion efficiency of 24.67% is realized and the device retain 91.5% of its initial PCE after ≈1300 h. The promising EPM strategy, which provides a principle of passivator design and allows passivation to be controllable, may advance further optimization and application of perovskite solar cells toward commercialization. [ABSTRACT FROM AUTHOR]

A decoupling control strategy of three‐phase inverter, which can realize complete decoupling of the active and reactive current in the synchronous reference frame (SRF) is proposed here. There are two coupling factors of current loop in SRF, one is time delay caused by digital control, and the other is AC filter. Dynamic time delay compensation is applied to eliminate coupling caused by the first factor. The phase of the bridge leg voltage can be predicted. The difference between it and the phase of reference voltage which takes part in pulse width modulation (PWM) is the dynamic compensation angle, which can compensate the time delay. High‐order feedforward compensation is applied to eliminate coupling caused by the second factor. Complex vector model of the LCL filter is derived and the high‐order coupling coefficients can be offset by feedforward compensation. The coupling characteristics and compensation principles are analysed in detail. The system stability is discussed. Finally, the simulation and experimental results are given to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

The identification of bioactive compounds in complex matrices remains a major challenge due to the lack of highly efficient and specific methods. This work developed an approach based on high‐performance affinity chromatography to identify the potential antitussive compounds from Zhisou oral liquid. The main methods include the synthesis of immobilized beta2‐adrenoceptor by a one‐step method, the screening and identification of the potential bioactive compounds by the receptor column coupled with mass spectrometry, and the binding mechanism analysis of the compounds to the receptor by the in vivo experiment, injection amount dependent method and molecular simulation. We identified the potential bioactive compounds of Zhisou oral liquid as glycyrrhizic acid, platycodin D, tuberostemonine, and hesperidin. In vivo experiment showed that the combinational utilization of the four compounds was possible to present an equivalent antitussive effect to the formula. The docking results demonstrated that hydrogen bonds and Van der Waals forces were the main forces to drive the binding of the four compounds to beta2‐adrenoceptor. We concluded that the four compounds are the effective components in Zhisou oral liquid. The proposed strategy is possible to provide an alternative for the development of highly efficient methods to pursue the bioactive compounds of complex matrices. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: An intermolecular [4 + 2] cycloaddition was realized through C—C bond cleavage in the presence of Rh(I) catalyst. The selective ring opening of 2‐alkylenecyclobutanols enables the generation of active alkenylrhodium species, which underwent smooth cross addition over alkynes and (E)‐2‐nitroethenylbenzene, leading to highly substituted all‐carbon six‐membered rings in a single step and in a complete atom economy. [ABSTRACT FROM AUTHOR]

Abstract: The state‐of‐power (SOP) of a Li‐ion battery (LIB) is an important evaluation index for safety control and energy recovery in electric vehicles. Major state estimation methods are only applicable to fixed room temperature at 20 °C, although the battery capacity and resistance vary dramatically with a change in battery surface temperature in the working process of the battery. This causes significant errors in state estimation if only room temperature is assumed. The inaccurate state may cause further excessive current at high or low temperatures to affect safety and life cycle of the battery. Therefore, a novel state estimation method applicable to various battery surface temperatures is developed here. This method uses capacity–temperature and resistance–temperature relationships from experimental data to more accurately predict battery capacity and resistance over the full temperature range. It then applies the extended Kalman filter (EKF) technique to estimate the state‐of‐charge, and a method of constrained multi‐parameter algorithm (CMPA) to estimate the SOP of LIBs. Simulation and experimental results show that the proposed method can obtain accurate SOP results at different temperatures. [ABSTRACT FROM AUTHOR]

Background Sarcomere gene mutation and myocardial fibrosis are both associated with poorer clinical outcomes in patients with hypertrophic cardiomyopathy (HCM). The aim of this study was to determine the relationship between sarcomere gene mutation and myocardial fibrosis measured by both histopathology and cardiac magnetic resonance (CMR). Methods and Results Two hundred twenty-seven patients with HCM who underwent surgical treatment, genetic testing, and CMR were enrolled. We retrospectively analyzed basic characteristics, sarcomere gene mutation, and myocardial fibrosis measured by CMR and histopathology. In our study, the mean age was 43 years, and 152 patients (67.0%) were men. A total of 107 patients (47.1%) carried a positive sarcomere gene mutation. The myocardial fibrosis ratio was significantly higher in the late gadolinium enhancement (LGE)+ group (LGE+ 14.3±7.5% versus LGE- 9.0±4.3%; P =0.001). Patients with HCM with SARC+ showed a high probability of fibrosis both in histopathology (myocardial fibrosis ratio 15.3±8.0% versus 12.4±6.5%; P =0.003) and CMR examination (LGE+ 98.1% versus 84.2%; P <0.001; LGE quantification 8.3% versus 5.8%; P <0.001). Linear regression analysis showed that sarcomere gene mutation (B=2.661; P =0.005) and left atrial diameter (B=0.240; P =0.001) were related factors for histopathological myocardial fibrosis. Also, the myocardial fibrosis ratio was significantly higher in the MYH7 (myosin heavy chain) group ( MYH7 18.1±9.6% versus MYBPC3 [myosin binding protein C] 13.1±5.2%; P =0.019). Conclusions Patients with HCM with positive sarcomere gene mutation had a higher myocardial fibrosis extent than patients without mutation, and a significant difference in myocardial fibrosis was also observed between the MYBPC3 and MYH7 groups. In addition, a high consistency was found between CMR-LGE and histopathological myocardial fibrosis in patients with HCM.

Background Obesity is an established cardiovascular risk factor in patients with hypertrophic cardiomyopathy. Postoperative atrial fibrillation (POAF) is one of the most common complications after surgery in patients with obstructive hypertrophic cardiomyopathy (OHCM). We aimed to determine the impact of body mass index (BMI) on the occurrence of POAF in patients with OHCM who underwent septal myectomy. Methods and Results In all, 712 OHCM patients without previous atrial fibrillation who underwent septal myectomy were identified. Patients were stratified into 3 groups based on BMI. Of these, 224 (31.5%) had normal weight (BMI<24 kg/m 2 ), 339 (47.6%) were overweight (BMI, 24 to <28 kg/m 2 ), and 149 (20.9%) were obese (BMI≥28 kg/m 2 ). Overweight and obese patients had increased levels of left atrial diameter ( P <0.001) and left ventricular end-diastolic diameter ( P <0.001), compared with patients with normal weight. Among 184 patients (25.8%) developing POAF, 32 cases (14.3%) occurred in the normal weight group, 100 cases (29.5%) occurred in the overweight group, and 52 cases (34.9%) occurred in the obese group ( P <0.001). Logistic regression analysis indicated that overweight (odds ratio [OR]: 2.161, 95% CI, 1.333-3.503; P =0.002) or obesity (OR, 2.803; 95% CI, 1.589-4.944; P <0.001), age (OR, 1.037; 95% CI, 1.018-1.057; P <0.001), and left atrial diameter (OR, 1.060; 95% CI, 1.027-1.095; P <0.001) were independently associated with the occurrence of POAF in patients with OHCM. Conclusions Overweight and obesity are strong predictors of POAF in patients with OHCM. Strategies aimed at lowering BMI may be a potential way to prevent POAF.