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• The effect of components in flue gas on commercial SCR catalyst was summarized. • The mechanisms of multifactorial synergism on VWT catalysts were first clarified. • Comprehensive approach to extend the lifetime of commercial catalysts was presented. • Concepts for catalyst lifetime prediction and management were reported. NO x does great harm to the environment and human beings. The selective catalytic reduction (SCR) of NO x with NH 3 is proven to be a mature technology to eliminate NO x from the waste gas, in which V 2 O 5 -WO 3 (MoO 3)/TiO 2 is the commercialized catalyst system. Lifetime is recognized as an important parameter to evaluate the practicality of the catalyst. However, this parameter is difficult to determine because of the variable flue gas conditions. Therefore, it is necessary to understand the impacts of different components on the deNO x performance of the catalysts so that rational lifetime management methods can be adopted. This advance would be introduced in this review first. Then the synergistic effects of multi-poisons on the catalysts would be summarized and illustrated. In accordance with these studies, some modification was conducted to enhance the catalyst's anti-poisoning ability to achieve the goal of prolonging the lifetime of the catalysts. Moreover, the latest research advances in the lifetime prediction of the SCR catalysts and the relevant management systems were summarized in the following section. This paper aims to provide theoretical guidance for simulating the catalyst deactivation process under actual conditions and shows a direction for constructing catalyst lifetime management systems. [ABSTRACT FROM AUTHOR]

To observe the clinical effect of acupoint catgut embedding combined with auricular plaster therapy in the treatment of children with vocal tic disorders. Catgut embedding was performed at the acupoints Bǎihuì (百会GV20), Shéntíng (神庭GV24), Dàzhuī (大椎GV14), Shēnzhù (身柱GV12), Fèishū (肺俞BL13), and Wèishū (胃俞BL21), and then auricular plaster sticking was applied to the acupoints Yānhóu(咽喉TG3), Fèi(肺CO14), Wèi (胃CO4), Jiāogăn(交感AH6a), Pízhìxià(皮质下AT4). After treatment, the Yale Global Tic Severity Scale (YGTSS) scores of the patients were significantly reduced (P <0.05), 5 cases were clinically cured, 8 cases remarkably effective, 12 cases effective, 5 cases ineffective, and the total effective rate was 83.33%. Acupoint catgut embedding combined with auricular plaster therapy for vocal tic disorders was effective, being worthy of clinical popularization. [ABSTRACT FROM AUTHOR]

To observe the clinical therapeutic effect on refractory peripheral facial paralysis treated with the combination of warming-needle moxibustion and stuck-needle-pulling therapy. A total of 33 patients with refractory peripheral facial paralysis were treated with the combination of warming-needle moxibustion and stuck-needle-pulling technique. The treatment was given once daily and there were 2 days at interval after consecutive 5 treatments. A total of 10 treatments made one course and consecutive 2 courses of treatment were required. Before and after treatment, House-Brackmann (H-B) facial nerve grading scale score was adopted to evaluate the degree of facial paralysis in the patients and the clinical effect was assessed. After treatment, the mean H-B score was higher than that before treatment in the patients, indicating a statistical significance (P < 0.05). After treatment, of 33 cases, 12 cases were cured, 9 cases effective remarkably, 8 cases effective and 4 cases no effect. The total effective rate was 87.88%. The combination treatment of warming-needle moxibustion and stuck-needle-pulling technique achieves a definite effect on refractory peripheral facial paralysis. [ABSTRACT FROM AUTHOR]

Prof. Min LI adopted acupoint catgut embedding at Zhōngwǎn (中脘CV12), Tiānshū (天枢ST25), Wèishū(胃俞BL21), Dàchángshū(大肠俞BL25), Zúsānlǐ (足三里ST36), Sányīnjiāo (三阴交SP6), and Tàichōng (太冲LR3), and combined with auricular plaster therapy at Wèi (胃 CO4) , Dà cháng (大肠 CO7) , Gān (肝CO12) ,Jiāogăn (交感 AH6a) ,Nèifēnmì (内分泌CO18) for the treatment of 18 cases of bulimia nervosa(BN). The result was that 9 cases were clinically cured, 6 cases improved, 3 case ineffective, and the total effective rate was 83.33%, no obvious adverse reactions. The therapeutic effect of acupoint catgut embedding combined with auricular plaster therapy for BN is good, without side effects. [ABSTRACT FROM AUTHOR]

Developing an understanding of the cavity stability underlying the metalorganic chemical vapor deposition (MOCVD) of ZnO is critical to the fabrication of oxide-based devices. Therefore, computational fluid dynamics (CFD) was used to study the process parameters (e.g., the growth temperature, total gas flow, chamber pressure, and substrate speed) of the MOCVD H-type reaction chamber for four states in the cavity: buoyancy-induced flow, plug flow, rotating-plug flow, and rotating flow. Based on these states, criteria for determining stable and unstable flows were determined. These can be presented on the pressure–rotation rate spectrum, which can be used to visualize the effects of specific process parameters on the flow stability. In order to obtain a good film deposition rate in the stable flow state of the cavity, a response surface model and genetic algorithm were also used to optimize the process parameters. The coefficient of variation of the optimized ZnO film was reduced to 2%, which greatly improved the film quality. This study provides a comprehensive insight into the transport phenomena of the MOCVD H-type reaction chamber, including coupled heat and mass transfer and chemical reactions, and presents the optimal combination of parameters to provide a useful reference for obtaining high-quality thin films. [ABSTRACT FROM AUTHOR]

Great efforts have been made in China to retrofit and upgrade the existing municipal wastewater treatment plants (WWTPs) for enhanced removal of organic substrates and in particular nutrients. However, the removal of trace recalcitrant or hazardous organic chemicals, e.g. steroid estrogens, one group of typical endocrine disrupting chemicals, has long been overlooked. The extensive investigations on estrogen removal rates in global and Chinese WWTPs and the estrogen biodegradation kinetics results in batch laboratory experiments are reviewed in this study. The effects of estrogen initial concentration and nitrifying activated sludge are highlighted. Challenges existing in current estrogen studies are pointed out, which are relevant for researches on fate and behavior of similar down-the-drain chemicals in both Chinese and global WWTPs. [Copyright &y& Elsevier]

• Cr and Mn atoms are the main active sites over CrMn 1.5 O 4 (1 0 0) surface. • A reaction scheme for the reduction of NO on the surface of CrMn 1.5 O 4 catalyst is proposed. • The generation of N 2 is accomplished in two main steps. • The energy barrier for the reaction to generate NO 2 is extremely low and contributes significantly to the reduction of NO. A comprehensive study of the catalytic behavior of CrMn 1.5 O 4 catalysts in the selective catalytic reduction (SCR) of nitrogen oxides (NO x) using NH 3 as the reductant was presented. The active sites for NO x reduction and NH 3 adsorption on the CrMn 1.5 O 4 surface were identified by density functional theory (DFT) calculations. The study elucidates the mechanism of NH 3 dehydrogenation and NO reduction, revealing key intermediates and reaction pathways. DFT calculation results showed that the chromium and manganese atoms on the surface, participating in the specifically d − sp hybridization with NH 3 , NO, played a key role in adsorption, and that NH 3 dehydrogenation led to the formation of NH 2 , which was a key intermediate in the selective catalytic reduction reaction. To further understand the process of NO generation to NO 2 and N 2 O on the surface of CrMn 1.5 O 4 catalyst, the chain reaction steps of NO reduction were proposed. Among them, NO was oxidized to NO 2 , and the very low reaction energy barrier contributed greatly to the fast SCR reaction, while the generation of the unwanted product N 2 O had a relatively high energy barrier, so the reaction was not easy to occur. These findings contribute to a deeper understanding of the intricate catalytic behavior of CrMn 1.5 O 4 catalysts, which will aid in the development of better SCR catalysts for the effective removal of NO x in industrial settings. [ABSTRACT FROM AUTHOR]

Commercially, semiconductor thin films for use in electronic devices are typically produced by processes such as chemical vapor deposition. This requires the gas flow, heat distribution, and concentration distribution above the substrate in the reactor to be carefully controlled to ensure that the growth rate and thickness uniformity of the thin film are appropriate. This work involved the simulation of a gallium nitride metal-organic chemical vapor deposition (GaN-MOCVD) reactor with a vertical spray structure. The simulation, which was conducted by using computational fluid dynamics software, enabled us to obtain a numerical solution under steady-flow low-pressure conditions with substrate axisymmetrical rotating. The temperature field, flow field, operating pressure, and rotation speed of the substrate were analyzed, and process conditions were optimized. These conditions make it possible to stabilize the flow field in the reactor to ensure thickness uniformity of the deposited thin film. These results not only provide an effective solution for high-quality epitaxial growth, but also provide a theoretical basis for follow-up experiment and equipment improvement. [ABSTRACT FROM AUTHOR]

Abstract: Early growth response (EGR) genes are thought to have a role in the pathogenesis of schizophrenia because of their conserved DNA binding domain and biologically activity in neuronal plasticity. This zinc-finger motif could influence gene post-translational modification and expression. The multigenetic association model, using markers in genes of similar or antagonistic biological effects within a signal pathway or gene family, might be more appropriate to this aspect of the schizophrenia hypothesis than the single gene strategy. In this study we investigated the role of EGR1, EGR2, EGR3 and EGR4 within the EGR family. Taqman technology was used to examine 12 single nucleotide polymorphisms (SNPs) covering these four genes in 2044 Chinese Han subjects. Case–control analyses were performed to detect association of these 4 genes with schizophrenia and multifactor dimensionality reduction (MDR) analysis was employed to examine their potential gene–gene interaction in schizophrenia. Neither allelic nor genotypic single-locus tests revealed any significant association between EGR1–4 and the risk of schizophrenia nor was any such association found with regard to interaction within EGR1–4 (p min =0.623, CV Consistency=10/10). We concluded that although multiple candidate genes are involved in schizophrenogenic development, the EGR family may not play a major role in schizophrenia susceptibility in the Chinese Han population. [Copyright &y& Elsevier]

Abstract: Schizophrenia has been linked with dysfunctions of glutamatergic, dopaminergic, and serotonergic neurotransmission. Dopamine- and cAMP-regulated phosphoprotein of relative molecular mass 32 kDa (DARPP-32), encoded by PPP1R1B (protein phosphatase 1, regulatory/inhibitor subunit 1B) gene, is enriched in neostriatal medium spiny neurons. It plays a key regulator role in dopaminergic and glutamatergic signaling pathways. The combined evidence from reduced DARPP-32 expression in the dorsolateral prefrontal cortex (DLPFC) in schizophrenic patients and from abnormalities in mice with a genetic deletion of DARPP-32 or with point mutations in phosphorylation sites of DARPP-32 suggested that it would be worthwhile to investigate the association between DARPP-32 and schizophrenia. In the present study, we genotyped five single nucleotide polymorphisms (SNPs) in the PPP1R1B gene and conducted a case-control study involving 520 schizophrenic patients and 386 healthy subjects drawn from the Chinese population. No allelic, genotypic or haplotypic association was found. However, our results do not preclude the possibility that the PPP1R1B is a susceptibility gene for schizophrenia in the Chinese population, since, as a central molecular switch, PPP1R1B may contribute to schizophrenia by interacting with other genes. Further functional analysis and genetic association studies are needed to determine the potential roles of PPP1R1B and other related genes in the pathophysiology of schizophrenia. [Copyright &y& Elsevier]