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Previous studies have verified that teacher-student relationship quality has a positive effect on students' academic engagement. Few studies, however, have examined whether school psychological capital mediates the linkage between teacher-student relationship and academic engagement. The present study aimed to examine the mediated role of school PsyCap between teacher-student relationship and academic engagement in a sample of 986 Chinese college students in their English as a foreign language (EFL) learning. Having controlled for gender and family resources, structural equation modelling (SEM) analysis was conducted to explore the predictive effect of the teacher-student relationship on academic engagement via mediator of school PsyCap. Results showed that the teacher-student relationship predicted school PsyCap. School PsyCap, in turn, predicted EFL learners' academic engagement. The present study provides evidence for the linkage between teacher-student relationship and academic engagement and contributes to the literature by uncovering the mediator mechanism between these two constructs. Both theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

Due to the demand for temporary rapid grid connection in renewable energy power plants, the topology structure of T-connected power lines has been widely used in the power grid. In this three-terminal system, fault localization is difficult because of traditional impedance-based or traveling wave-based fault localization methods; the three-terminal data should be synchronized and communicated. Since different terminal assets belong to different enterprises, it is actually difficult to maintain good synchronization between them. Therefore, in practical applications, the fault location of T-connected power lines often fails. This article proposes a single terminal fault location method for a T-connection power line to address this issue. It is based on the fact that the local topology of the T-connected power line in the healthy phase remains unchanged during the fault-clearing process. It utilizes the sequential current and voltage data changes generated by the sequential tripping ping emitted by the circuit breaker from different terminals to describe the constant topology of the healthy phase as an equation and calculates the accurate fault location after solving the equation. The Levenberg–Marquardt algorithm was used to calculate fault distance and transition resistance, and the effectiveness of this method was verified through simulation. [ABSTRACT FROM AUTHOR]

With the large-scale integration of distributed renewable energy into low-voltage distribution station areas, rapidly growing services put forward new requirements on transparent monitoring. In order to accurately and objectively quantify the transparency of various distribution station areas and measure the impact of different dimensional indexes on the transparency evaluation of distribution station areas, this paper proposes a confidence relative offtarget distance-based multi-dimensional transparency evaluation method. First, a multi-dimensional transparency evaluation index system with electrical and communication integration is constructed. Second, an improved gray target model combining both positive and negative target vectors is established to realize bi-directional quantitative analysis. Then, the relative off-target distance is calculated based on the endowment coefficient by leveraging both subjective and objective weights. Finally, the confidence of the relative off-target distance is calculated based on fuzzy entropy to improve the reliability of transparency evaluation. The simulation results show that this method can effectively distinguish the transparency gap between different distribution station areas, identify the single dimensional index with the greatest contribution or potential, and verify the effectiveness of the proposed method applied to the transparency evaluation of distribution station areas. [ABSTRACT FROM AUTHOR]

Necroptosis is a form of regulated cell death that has been implicated in multiple diseases. TNF-induced necroptosis is regulated by necrosomes, complexes consisting of RIPK1, RIPK3 and MLKL. In this study, by screening of a small-compound library, we identified dozens of compounds that inhibited TNF-induced necroptosis. According to the mechanisms by which they inhibited necroptosis, these compounds were classified into different groups. We then identified Ibrutinib as an inhibitor of RIPK3 and found that Quizartinib protected against the TNF-induced systemic inflammatory response syndrome in mice by inhibiting the activation of RIPK1. Altogether, our work revealed dozens of necroptosis inhibitors, suggesting new potential approaches for treating necroptosis-related diseases. Screening a library of compounds identifies several inhibitors of TNF-induced necroptosis, including Ibrutinib as an inhibitor of RIPK3 and Quizartinib as an indirect RIPK1 kinase activity inhibitor. [ABSTRACT FROM AUTHOR]

Vascular smooth muscle cells (VSMCs) proliferation is a critical event that contributes to the pathogenesis of vascular remodeling such as hypertension, restenosis, and pulmonary hypertension. Increasing evidences have revealed that VSMCs proliferation is associated with the activation of receptor tyrosine kinases (RTKs) by their ligands, including the insulin-like growth factor receptor (IGFR), fibroblast growth factor receptor (FGFR), epidermal growth factor receptor (EGFR), vascular endothelial growth factor receptor (VEGFR), and platelet-derived growth factor receptor (PDGFR). Moreover, some receptor tyrosinase inhibitors (TKIs) have been found and can prevent VSMCs proliferation to attenuate vascular remodeling. Therefore, this review will describe recent research progress on the role of RTKs and their inhibitors in controlling VSMCs proliferation, which helps to better understand the function of VSMCs proliferation in cardiovascular events and is beneficial for the prevention and treatment of vascular disease. [ABSTRACT FROM AUTHOR]

Circuit breakers on the filter bank branches in converter stations are vulnerable to contact wear and mechanical deterioration caused by frequent operations, which can lead to circuit breaker breakdowns and explosions. It is imperative to conduct research on the early detection of abnormal states in circuit breakers. Existing electrical quantity-based detection methods are constrained by a priori assumptions, and their measurement methods are susceptible to interference, leading to misjudgments. To address this issue, this paper examines the influence of changes in critical breakdown field strength and contact spacing on circuit breaker operation states. It also proposes a technical scheme that employs breakdown current values to comprehensively characterize circuit breaker operation states, replacing the use of critical breakdown field strength and contact spacing. An early detection method for abnormal circuit breaker states based on a sequence of breakdown current ratios at different times is proposed, and its effectiveness is verified through simulation and field recording data. [ABSTRACT FROM AUTHOR]

Under the current trend of power electronics in energy systems, a high percentage of renewable energy transports clean energy to the grid through grid-connected inverters. The pulse-width modulation (PWM) technique brings high-order harmonics near to the switching frequency, and LCL filters with low-pass characteristics become the common choice for grid-connected inverters. However, the low-order harmonics caused by nonideal switching characteristics are difficult to filter out, and the new resonance point introduced by the LCL filter causes a security problem for the energy systems. Firstly, the generation mechanism of the 6 k ± 1 order harmonic and high-frequency resonance from a PV grid-connected inverter is analyzed. Then, a virtual resistor is constructed by the active damping method to absorb the resonant component. Meanwhile, this paper also presents an adaptive modulation voltage compensation method to decrease the low-order harmonics. Finally, the actual measured data of user photovoltaic (PV) and multiple comparative simulations verify these theories. Simulation results show that the proposed coordinated control algorithm reduces the peak of the resonance point, and the rate of low-order harmonics mitigation is more than 50%. The proposed method is suitable for various operating conditions. [ABSTRACT FROM AUTHOR]

The primary control goals of a wind turbine (WT) are structural load shedding, maximum wind energy capture in the underpowered situation, and consistent power production in the full power condition. A crucial component of the control problem for wind turbines with varying speeds is maximum power tracking control. Conventional maximum power tracking control tracks the ideal blade tip speed ratio to provide the most wind power at the specified wind speeds. However, because of the wind turbine's great nonlinearity and the significant external disturbances it encounters, it is difficult to react quickly to variations in wind speed, and the tracking speed is sluggish, which lowers the amount of electricity produced annually. In light of this, this work develops a novel preset performance controller for a wind power system maximum power tracking control. With this technique, the convergence rate and tracking precision may be set. In particular, based on the concept of time-varying feedback, a time-varying function, known as the preset performance function, is first created to allow the convergence speed and accuracy to be predetermined; then this time-varying function is used to transform the actual specified time problem of the original system into a bounded time problem of the new system; finally, a direct robust controller design strategy with pre-defined performance is suggested based on the design concept of the backstepping technique. The plan may maximize the rotor power coefficient by altering the wind turbine speed, track the ideal blade tip speed ratio for a given tracking accuracy and speed, and get the most wind power to produce the most power with the strongest robustness. The simulation results show that the recommended control technique works. [ABSTRACT FROM AUTHOR]

Pulmonary arterial hypertension (PAH) is a chronic and fatal disease characterized by pulmonary vascular remodeling, similar to the 'Warburg effect' observed in cancer, which is caused by reprogramming of glucose metabolism. Oroxylin A (OA), an active compound derived from Scutellaria baicalensis, which can inhibit glycolytic enzymes [hexokinase 2 (HK2), Lactate dehydrogenase (LDH), and pyruvate dehydrogenase kinase 1 (PDK1) by downregulating aerobic glycolysis to achieve the treatment of liver cancer. To the best of our knowledge, however, the impact of OA on PAH has not been addressed. Consequently, the present study aimed to evaluate the potential protective role and mechanism of OA against PAH induced by monocrotaline (MCT; 55 mg/kg). The mean pulmonary artery pressure (mPAP) was measured using the central venous catheter method; HE and Masson staining were used to observe pulmonary artery remodeling. Non-targeted metabolomics was used to analyze the metabolic pathways and pathway metabolites in MCT-PAH rats. Western Blot analysis was employed to assess the levels of glucose transporter 1 (Glut1), HK2), pyruvate kinase (PK), isocitrate dehydrogenase 2 (IDH2), pyruvate dehydrogenase kinase 1(PDK1), and lactate dehydrogenase (LDH) protein expression in both lung tissue samples from MCT-PAH rats. The results demonstrated that intragastric administration of OA (40 and 80 mg/kg) significantly decreased mPAP from 43.61±1.88 mmHg in PAH model rats to 26.51±1.53 mmHg and relieve pulmonary artery remodeling. Untargeted metabolomic analysis and multivariate analysis indicated abnormal glucose metabolic pattern in PAH model rats, consistent with the Warburg effect. OA administration decreased this effect on the abnormal glucose metabolism. The protein levels of key enzymes involved in glucose metabolism were evaluated by western blotting, which demonstrated that OA could improve aerobic glycolysis and inhibit PAH by decreasing the protein levels of Glut1, HK2, LDH, PDK1 and increasing the protein levels of PK and IDH2. In conclusion, OA decreased MCT-induced PAH in rats by reducing the Warburg effect. [ABSTRACT FROM AUTHOR]

The hydraulic turbine governing system (HTGS) is a complex nonlinear system that regulates the rotational speed and power of a hydro-generator set. In this work, an incremental form of an HTGS nonlinear model was established and the Takagi–Sugeno (T-S) fuzzy linearization and mixed H2/H∞ robust control theory was applied to the design of an HTGS controller. A T-S fuzzy H2/H∞ controller for an HTGS based on modified hybrid particle swarm optimization and gravitational search algorithm integrated with chaotic maps (CPSOGSA) is proposed in this paper. The T-S fuzzy model of an HTGS that integrates multiple-state space equations was established by linearizing numerous equilibrium points. The linear matrix inequality (LMI) toolbox in MATLAB was used to solve the mixed H2/H∞ feedback coefficients using the CPSOGSA intelligent algorithm to optimize the weighting matrix in the process so that each mixed H2/H∞ feedback coefficients in the fuzzy control were optimized under the constraints to improve the performance of the controller. The simulation results show that this method allows the HTGS to perform well in suppressing system frequency deviations. In addition, the robustness of the method to system parameter variations is also verified. [ABSTRACT FROM AUTHOR]

This study validated the school psychological capital (PsyCap) scale in the Chinese context and examined the predictive effect of PsyCap resources on academic engagement and achievement emotions. Self-report data for PsyCap resources, student engagement, enjoyment, anxiety, and boredom toward English learning were collected from 1,000 sophomores. Item-level analyses and confirmatory factor analysis were used to verify the validity of the school PsyCap scale, and structural equation modeling was applied to reveal the predictive effect of school PsyCap resources on academic engagement and achievement emotions. Results showed that the school PsyCap scale retained superior psychometric properties. Besides, PsyCap resources were demonstrated to have a positive relationship to academic engagement and enjoyment, and a negative relationship to anxiety and boredom. The effectiveness of the school PsyCap scale was verified among Chinese college students, and besides the traditional predictors, school PsyCap is also critically important for students' academic engagement and achievement emotions. Limitations and implications are discussed. [ABSTRACT FROM AUTHOR]

Propane oxidative dehydrogenation (ODH) is an energy-efficient approach to produce propylene. However, ODH suffers from low propylene selectivity due to a relatively higher activation barrier for propylene formation compared with that for further oxidation. In this work, calculations based on density functional theory were performed to map out the reaction pathways of propane ODH on the surfaces (001) and (010) of nickel oxide hydroxide (NiOOH). Results show that propane is physisorbed on both surfaces and produces propylene through a two-step radical dehydrogenation process. The relatively low activation barriers of propane dehydrogenation on the NiOOH surfaces make the NiOOH-based catalysts promising for propane ODH. By contrast, the weak interaction between the allylic radical and the surface leads to a high activation barrier for further propylene oxidation. These results suggest that the catalysts based on NiOOH can be active and selective for the ODH of propane toward propylene. [ABSTRACT FROM AUTHOR]

While an increasing literature on multilingualism addresses the key role of language in access to social resources, including crisis communication, little attention has been paid to practices of English-mediated multilingualism. Based on semi-structured interviews with 10 international students from South Asia and Southeast Asia receiving their higher education in China, the study reveals what language-related challenges international students encounter, how they mobilize their multilingual resources to enhance their access to crisis communication and build a shared community, and how their multilingual competences are valorized and enacted in the shifting paradigm of the China-oriented new economy addressing mutual accountability in South-South cooperation. The study suggests that English-mediated multilingualism in China fails to bridge the needs of international students of diverse backgrounds. The study also calls attention to the shifting paradigm of multilingual studies and the necessity of addressing the real world problems of health communication in a diverse context. [ABSTRACT FROM AUTHOR]

Rhubarb is commonly used to treat constipation in China for its function of promoting intestinal movement and optimum water content in feces. However, its mechanism of mucus secretion is vague. The aim of the study is to investigate the role of mast cells and enteric neurons in rhubarb extract (RE)-induced mucus secretion in the rat colon. Immunofluorescence was used to detect histamine receptors. Western blotting and 3,3′-diaminobenzidine (DAB) were applied to explore the content changes of mast cells activation. The changes in colonic goblet cells (GCs) were determined by means of PAS/AB staining. An intestinal perfusion system with a Bradford protein assay kit was directly to estimate in vitro secretion. And the cytokines were investigated with ELISA. The longitudinal aspect of this study indicate that the number and water content of faecal pellets were enhanced after the administration of different doses of RE accompanied by mast cells accumulated and increased the content of interferon (IFN) -γ or decreased the levels of interleukin (IL) −10 at doses of 3 and 6 g/kg. Pretreatment with ketotifen, mast cell stabilizer, had partially inhibited on RE-induced mucus secretion. Furthermore, RE induced the release of acetylcholine and mucin-2 in the colonic tissue and the histamine levels from the faeces. The results suggest that RE induced colonic mucus secretion involves mast cell activation and some cytokine. [ABSTRACT FROM AUTHOR]

Introducing ethynylene linkages in a conjugated molecule can deepen the HOMO level, decrease the steric constraints and better delocalize the π electrons and so on, which are beneficial for organic solar cells. Furthermore, the typical method of introducing acetylene linkages by Sonogashira reactions can avoid the usage of toxic stannyl intermediates and potentially dangerous lithiation reactions. In this study, two simple small molecules BEDPP and NEDPP are designed and synthesized, in which two diketopyrrolopyrrole units are symmetrically connected to benzene and naphthalene cores, respectively, via acetylene linkages. And the BHJ (Bulk Heterojunction) solar cells based on BEDPP and NEDPP without using solvent additive and without any post-treatment for the active layers provide us power conversion efficiencies of 1.48% and 2.31% with remarkably high open circuit voltages up to 0.90 and 0.98 V, respectively. [ABSTRACT FROM AUTHOR]

The unique properties of boron dipyrromethene (BODIPY) dyes including facile synthesis, high absorption coefficients, and delocalized molecular orbitals as well as excellent photochemical and thermal stability, make them promising as materials for organic solar cells. Accordingly, in this study three A- D-A structural small molecules of BDTT-BODIPY, FL-BODIPY, and TT-BODIPY have been synthesized, in which two BODIPY acceptor units are symmetrically conjugated to 4,8-bis(5-(2-ethylhexyl) thiophen-2-yl)benzo[1,2-b:4,5-b]dithiophene (BDTT), 9,9-dioctyl-9H-fluorene (FL), and thieno[3,2-b]thiophene (TT) donor cores, respectively. The manipulation of the structural parameters significantly improves the performances of the BHJ OSCs, which show power conversion efficiencies of 4.75 %, 1.51 %, and 1.67 % based on [6,6]-phenyl C71-butyric acid methyl ester (PC71BM) as the acceptor material and BDTT-BODIPY, FL-BODIPY, and TT-BODIPY as the donor materials, respectively. [ABSTRACT FROM AUTHOR]

The auto-phosphorylation of murine receptor-interacting protein 3 (Rip3) on Thr 231 and Ser 232 in the necrosome is required to trigger necroptosis. However, how Rip3 phosphorylation is regulated is still largely unknown. Here we identified protein phosphatase 1B (Ppm1b) as a Rip3 phosphatase and found that Ppm1b restricts necroptosis in two settings: spontaneous necroptosis caused by Rip3 auto-phosphorylation in resting cells, and tumour necrosis factor-α (TNF)-induced necroptosis in cultured cells. We revealed that Ppm1b selectively suppresses necroptosis through the dephosphorylation of Rip3, which then prevents the recruitment of mixed lineage kinase domain-like protein (Mlkl) to the necrosome. We further showed that Ppm1b deficiency (Ppm1bd/d) in mice enhanced TNF-induced death in a Rip3-dependent manner, and the role of Ppm1b in inhibiting necroptosis was evidenced by elevated Rip3 phosphorylation and tissue damage in the caecum of TNF-treated Ppm1bd/d mice. These data indicate that Ppm1b negatively regulates necroptosis through dephosphorylating Rip3 in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Formation of multi-component signaling complex necrosomes is essential for tumor necrosis factor α (TNF)-induced programmed necrosis (also called necroptosis). However, the mechanisms of necroptosis are still largely unknown. We isolated a TNF-resistant L929 mutant cell line generated by retrovirus insertion and identified that disruption of the guanine nucleotide-binding protein γ 10 (Gγ10) gene is responsible for this phenotype. We further show that Gγ10 is involved in TNF-induced necroptosis and Gβ2 is the partner of Gγ10. Src is the downstream effector of Gβ2γ10 in TNF-induced necroptosis because TNF-induced Src activation was impaired upon Gγ10 knockdown. Gγ10 does not affect TNF-induced activation of NF-κB and MAPKs and the formation of necrosomes, but is required for trafficking of necrosomes to their potential functioning site, an unidentified subcellular organelle that can be fractionated into heterotypic membrane fractions. The TNF-induced Gβγ-Src signaling pathway is independent of RIP1/RIP3 kinase activity and necrosome formation, but is required for the necrosome to function. [ABSTRACT FROM AUTHOR]

Viruses hijack host factors for their high speed protein synthesis, but information about these factors is largely unknown. In searching for genes that are involved in viral replication, we carried out a forward genetic screen for Drosophila mutants that are more resistant or sensitive to Drosophila C virus (DCV) infection-caused death, and found a virus-resistant line in which the expression of pelo gene was deficient. Our mechanistic studies excluded the viral resistance of pelo deficient flies resulting from the known Drosophila anti-viral pathways, and revealed that pelo deficiency limits the high level synthesis of the DCV capsid proteins but has no or very little effect on the expression of some other viral proteins, bulk cellular proteins, and transfected exogenous genes. The restriction of replication of other types of viruses in pelo deficient flies was also observed, suggesting pelo is required for high level production of capsids of all kinds of viruses. We show that both pelo deficiency and high level DCV protein synthesis increase aberrant 80S ribosomes, and propose that the preferential requirement of pelo for high level synthesis of viral capsids is at least partly due to the role of pelo in dissociation of stalled 80S ribosomes and clearance of aberrant viral RNA and proteins. Our data demonstrated that pelo is a host factor that is required for high efficiency translation of viral capsids and targeting pelo could be a strategy for general inhibition of viral infection. [ABSTRACT FROM AUTHOR]

Solution processed organic near-infrared (NIR) photodetectors (PDs) based on a porphyrin small molecule as a donor material and (6,6)-phenyl-C61-butyric acid methyl ester (PC61BM) as an acceptor material are reported. Operating at room temperature, these PDs show a low dark current density of 3.44 nA cm−2, a broad spectral response from 380 to 960 nm with high external quantum efficiencies around 20% in the NIR region at a bias of 0 V. Detectivities over 1012 cm H1/2 W−1 in the whole range from 380 to 930 nm are achieved, which rank as one of the best performances among previously reported NIR PDs. [ABSTRACT FROM AUTHOR]

Four new donor-acceptor (donor) [D-A(D)], PBDT-PTQ, PBDT-PTTQ, PBDT-TQ, and PBDT-TTQ, bearing the same backbone of alternative benzodithiophene (BDT) and quinoxaline units but with phenylene thienyl, phenylene di-thienyl, thienyl and di-thienyl groups (other donors), respectively, at the acceptor quinoxaline units, were designed and synthesized to investigate the impacts of the conjugated side chains at the acceptor units on the photovoltaic properties of polymers. The power conversion efficiencies (PCEs) of the polymer solar cells (PSCs) based on PBDT-TQ:[6,6]-phenyl-C-70-butyric acid methyl ester (PC70BM) and PBDT-PTQ:PC70BM reach to 4.39 and 3.58%, respectively, which are 43 and 17% higher, respectively, than that of a reported alkylphenyl substituted polymer with the same main chain. However, the PCEs based on PBDT-TTQ and PBDT-PTTQ, in which an additional thiophene is added at a side chain of PBDT-TQ and PBDT-PTQ, respectively, decline. The mechanism how the conjugated side chains affect the performance of the PSCs is also discussed. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 [ABSTRACT FROM AUTHOR]

Background: Myeloid cell leukaemia 1 (MCL1) is a pro-survival Bcl-2 family protein that plays important roles in cell survival, proliferation, differentiation and tumourigenesis. MCL1 is a fast-turnover protein that is degraded via an ubiquitination/proteasome-dependent mechanism. Although several E3 ligases have been discovered to promote the ubiquitination of MCL1, the deubiquitinating enzyme (DUB) that regulates its stability requires further investigation. Methods: The immunoprecipitation was used to determine the interaction between OTUD1 and MCL1. The ubiquitination assays was performed to determine the regulation of MCL1 by OTUD1. The cell viability was used to determine the regulation of BH3-mimetic inhibitor induced cell death by OTUD1. The survival analysis was used to determine the relationship between OTUD1 expression levels and the survival rate of cancer patients. Results: By screening a DUB expression library, we determined that the deubiquitinating enzyme OTUD1 regulates MCL1 protein stability in an enzymatic-activity dependent manner. OTUD1 interacts with MCL1 and promotes its deubiquitination. Knockdown of OTUD1 increases the sensitivity of tumour cells to the BH3-mimetic inhibitor ABT-263, while overexpression of OTUD1 increases tumour cell tolerance of ABT-263. Furthermore, bioinformatics analysis data reveal that OTUD1 is a negative prognostic factor for liver cancer, ovarian cancer and specific subtypes of breast and cervical cancer. Conclusions: The deubiquitinating enzyme OTUD1 antagonizes BH3-mimetic inhibitor induced cell death through regulating the stability of the MCL1 protein. Thus, OTUD1 could be considered as a therapeutic target for curing these cancers. [ABSTRACT FROM AUTHOR]

Free-surface related multiples exist widely in marine seismic data. Imaging with multiples rather than suppression has particular benefits because multiples have more information than primaries, such as wider illumination and higher vertical resolution. One-way wave-equation based pre-stack depth migration (OWPSDM) is an effective imaging tool with high calculation efficiency. By using an OWPSDM operator, primaries and multiples are imaged simultaneously. The artifacts caused by the cross-correlation between forward-propagated source and backward-propagated multiples can be suppressed by an approach with the following three steps: for the first step, the source is replaced by the recorded field data together with a wavelet and the data is the recorded field data. The imaging results contain both real structure images and artifacts. For the second step, the source is the wavelet and the data is replaced by the predicted free-surface related multiples. Artifacts can be obtained after using the imaging condition at each depth. Lastly, artifacts can be suppressed by adaptive subtraction from the images obtained in the first step. Numerical tests on synthetic data of a three-layer model show that our scheme provides regions with wider illumination and balanced image amplitudes compared to the images obtained with primaries only. Artifacts caused by the cross-correlation between a forward-propagated wavelet and backward-propagated free-surface multiples were properly predicted and suppressed. Applying the proposed method to real deep marine data shows that the image quality of deep target layers is improved, with balanced illumination and fewer artifacts. [ABSTRACT FROM AUTHOR]

The cover page of the journal "Chinese Journal of Chemistry" is presented.