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Medium-sized heterocycles are widespread among a spectrum of structurally intriguing and biologically significant natural products and synthetic pharmaceuticals. Metal-catalyzed high-order dipolar annulations resembling reactions of metal-containing reactive dipoles with dipolarophiles constitute a highly efficient and flexible strategy for constructing medium-sized heterocycles. Mechanistically, these annulation reactions usually proceeding through stepwise pathways are different from the classic high-order pericyclic reactions that follow the Woodward-Hoffman rules. More significantly, asymmetric high-order dipolar annulations using chiral organometallic catalysts have been proven successful for constructing chiral medium-sized heterocycles with high enantio- and diastereoselectivity. This review highlights the impressive advances in this area and is focused on the reactivity, scope, mechanisms and applications of high-order dipolar annulation reactions.
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Metais , CatáliseRESUMO
AIMS: To explore the psychological changes of nurses during home isolation, the factors that related with these changes, and coping strategies in home isolation during the epidemic of COVID-19 in China. DESIGN: A qualitative study based on grounded theory. METHODS: Individual semi-structured telephone interviews were conducted from January 2020-February 2020 with 10 nurses who were isolated at home sharing the experiences of the epidemic of COVID-19. All interviews were audio recorded, transcribed, and analysed using constant comparative data analysis. RESULTS: Analyses of the collected data reveal that the psychological changes of nurses during home isolation reflect a complex, dynamic, and gradually adaptive process that was affected by many factors. Nurses had many negative emotional reactions in the early stages of isolation and positive emotions gradually increased during home isolation. After release from home isolation, they become more confident and calm after. Six categories of coping strategies were identified, including reasoned cognition; autosuggestion; develop healthy protective behaviours; shifting attention; social support; and the power of a role model. CONCLUSIONS: The study provides a better understanding of the psychological changes and the coping strategies used among nurses isolated at home. It is necessary to pay more attention to negative emotions in the early stages of home isolation to help nurses adjust quickly. The coping strategies used by nurses are likely to help those in home isolation reduce negative psychological changes and experience more optimal self-adjustment. IMPACT: This study explored the psychological changes and coping strategies of home isolation among nurses, providing useful advice for psychologists to develop psychological crisis interventions to help individuals reduce negative psychological and have more actively coping strategies when faced sudden stressful infectious diseases.
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Adaptação Psicológica , Povo Asiático/psicologia , COVID-19/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Quarentena/psicologia , Estresse Psicológico , Adulto , China , Feminino , Teoria Fundamentada , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adulto JovemRESUMO
AIM: To describe a protocol that examines the feasibility and effectiveness of a face-to-face guided self-disclosure intervention for facilitating benefit finding and other related psychological outcomes for breast cancer patients. BACKGROUND: Benefit finding can promote a positive attitude among patients facing disease. However, limited studies have focused on improving benefit finding among breast cancer patients. Previous research has been based on group interventions, which may not suit all patients. Self-disclosure was recognized as a strong predictor of benefit finding. This protocol is based on a brief face-to-face disclosure intervention to improve benefit finding for breast cancer patients. DESIGN: A non-blinded randomized controlled trial. METHODS: A total of 154 patients with breast cancer who have undergone radical mastectomy will be randomly assigned to either the experimental group, which will participate in a six-session face-to-face individual intervention, or the control group at a ratio of 1:1. Baseline assessments will take place after the breast cancer diagnosis, with follow-up assessments at 3, 6 and 9 months after baseline. The primary outcome is benefit finding; other outcomes are self-disclosure, cognitive reappraisal, social support, optimism and medical coping modes. DISCUSSION: This study is to design a protocol for guided self-disclosure interventions to promote benefit finding in Chinese breast cancer patients. If this intervention is feasible and effective, it could be implemented in clinical practice. IMPACT: This study will provide useful advice for health professionals to guide breast cancer patients in benefit finding during stressful events. If it is effective, it will be implemented broadly in clinical practice.
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Adaptação Psicológica , Povo Asiático/psicologia , Neoplasias da Mama/psicologia , Revelação , Sobreviventes/psicologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adulto JovemRESUMO
The palladium-catalyzed Heck reaction is a well-known, Nobel Prize winning transformation for producing alkenes. Unlike the alkenyl and aryl variants of the Heck reaction, the alkyl-Heck reaction is still underdeveloped owing to the competitive side reactions of alkyl-palladium species. Herein, we describe the development of a deaminative alkyl-Heck-type reaction that proceeds through C-N bond activation by visible-light photoredox catalysis. A variety of aliphatic primary amines were found to be efficient starting materials for this new process, affording the corresponding alkene products in good yields under mild reaction conditions. Moreover, this strategy was successfully applied to deaminative carbonylative alkyl-Heck-type reactions.
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Leaf rolling is considered as one of the most important agronomic traits in rice breeding. It has been previously reported that SEMI-ROLLED LEAF 1 (SRL1) modulates leaf rolling by regulating the formation of bulliform cells in rice (Oryza sativa); however, the regulatory mechanism underlying SRL1 has yet to be further elucidated. Here, we report the functional characterization of a novel leaf-rolling mutant, curled leaf and dwarf 1 (cld1), with multiple morphological defects. Map-based cloning revealed that CLD1 is allelic with SRL1, and loses function in cld1 through DNA methylation. CLD1/SRL1 encodes a glycophosphatidylinositol (GPI)-anchored membrane protein that modulates leaf rolling and other aspects of rice growth and development. The cld1 mutant exhibits significant decreases in cellulose and lignin contents in secondary cell walls of leaves, indicating that the loss of function of CLD1/SRL1 affects cell wall formation. Furthermore, the loss of CLD1/SRL1 function leads to defective leaf epidermis such as bulliform-like epidermal cells. The defects in leaf epidermis decrease the water-retaining capacity and lead to water deficits in cld1 leaves, which contribute to the main cause of leaf rolling. As a result of the more rapid water loss and lower water content in leaves, cld1 exhibits reduced drought tolerance. Accordingly, the loss of CLD1/SRL1 function causes abnormal expression of genes and proteins associated with cell wall formation, cuticle development and water stress. Taken together, these findings suggest that the functional roles of CLD1/SRL1 in leaf-rolling regulation are closely related to the maintenance of cell wall formation, epidermal integrity and water homeostasis.
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Parede Celular/fisiologia , Oryza/fisiologia , Epiderme Vegetal/fisiologia , Folhas de Planta/fisiologia , Proteínas de Plantas/fisiologia , Clonagem Molecular , Desidratação/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Epiderme Vegetal/metabolismo , Proteínas de Plantas/metabolismo , Proteostase , Água/metabolismoRESUMO
Pheochromocytoma is a kind of rare tumor, occurring at any site in the sympathoadrenal system. Main lesions occur within the adrenal gland; only 1%-2% occur within the chest, and most of these are located in the posterior mediastinum. Intrapericardial pheochromocytoma is extremely rare in clinic, only about 100 cases have been reported in total in both the domestic and foreignliterature since Besterman et al. first reported in 1974. It is often difficult to diagnose and locate these tumors. Hence, we present here a case of adrenal combined with heart multiple pheochromocytomas and discuss about techniques contributed to diagnosis and localization.
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Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias Cardíacas/diagnóstico por imagem , Feocromocitoma/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Cintilografia , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
Here, we describe a novel [3 + 2] cycloaddition of 3-substituted indoles with vinyl aziridines and vinyl epoxides that provides a straightforward approach to pyrroloindolines and furoindolines bearing vinyl groups (up to 96% yield and 9:1 dr). In contrary to previous reports involving Lewis acid activation, this work reports successful reactions based on the activation of indole using t-BuOK and BEt3 (triethylborane), thereby preserving the free N-H group on indoles. In addition, a gram-scale reaction and a ring-closing metatheis reaction are performed to provide good demonstrations of the synthetic utility of this approach.
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Plasma membrane NADPH oxidases are major producers of reactive oxygen species (ROS) in plant cells under normal growth and stress conditions. In the present study the total activity of rice NADPH oxidases and the transcription of OsRbohA, which encodes an Oryza sativa plasma membrane NADPH oxidase, were stimulated by drought. OsRbohA was expressed in all tissues examined throughout development. Its mRNA was upregulated by a number of factors, including heat, drought, salt, oxidative stress and methyl jasmonate treatment. Compared with wild-type (WT), the OsRbohA-knockout mutant osrbohA exhibited upregulated expression of other respiratory burst oxidase homolog genes and multiple abnormal agronomic traits, including reduced biomass, low germination rate and decreased pollen viability and seed fertility. However, OsRbohA-overexpressing transgenic plants showed no differences in these traits compared with WT. Although osrbohA leaves and roots produced more ROS than WT, the mutant had lesser intracellular ROS. In contrast, OsRbohA-overexpressing transgenic plants exhibited higher ROS production at the intracellular level and in tissues. Ablation of OsRbohA impaired the tolerance of plants to various water stresses, whereas its overexpression enhanced the tolerance. In addition, a number of genes related to energy supply, substrate transport, stress response and transcriptional regulation were differentially expressed in osrbohA plants even under normal growth conditions, suggesting that OsRbohA has fundamental and broad functions in rice. These results indicate that OsRbohA-mediated processes are governed by complex signaling pathways that function during the developmental regulation and drought-stress response in rice.
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Regulação da Expressão Gênica de Plantas , NADPH Oxidases/metabolismo , Oryza/enzimologia , Transdução de Sinais , Acetatos/metabolismo , Membrana Celular/enzimologia , Ciclopentanos/metabolismo , Secas , Germinação , Mutação , NADPH Oxidases/genética , Oryza/citologia , Oryza/genética , Oryza/fisiologia , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/citologia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo , Plântula/citologia , Plântula/enzimologia , Plântula/genética , Plântula/fisiologia , Cloreto de Sódio/farmacologia , Estresse FisiológicoRESUMO
A copper-catalyzed decarboxylative amination/hydroamination sequence of propargylic carbamates with various nucleophiles is described for the first time. It features an earth-abundant metal catalyst, mild reaction conditions, and high efficiency. Further treatments of the resultant key intermediates using an acid or a base in one pot enable the controllable and divergent synthesis of two types of functionalized indoles. Moreover, experiments to demonstrate the synthetic potential of this methodology are performed.
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Wood electromagnetic shielding material, which was made by treating wood with electroless plating, not only keep the superior characteristics of wood, but also improve the conductivity, thermal conductivity and electromagnetic shielding properties of wood. The emergence of this material opens the way to the value-added exploitation of wood and widens the processing and application field for the electromagnetic shielding material. In order to explore the feasibility of using NIR technology to investigate the properties of wood electromagnetic shielding material, this study analysis the samples before and after copper plated process by the NIR spectroscopy coupled with principal component analysis (PCA). The results showed that (1) there exist significant differences between samples before and after copper plated process both on the spectral shape and absorption, and the great differences can also be seen in the samples with different treat time, especially for the samples with 5 min treat time; (2) after PCA analysis, six clusters from the samples before and after copper plated process were separately distributed in the score plot, and the properties of untreated wood and sensitized wood were similar, and the properties of samples for 25 and 40 min treat time were also similar in order that these samples were close to each other, all of which might suggest that the NIR spectroscopy reflected major feature information about material treatment; (3) After comparing the PCA performance between NIR and visible spectral region, it could be found that the classification performance of samples before and after copper plated process based on the NIR region were better than that based on the visible region, and the information of color on the surface of samples were preferably reflected in the visible region, which could indicate that there are more information about samples' surface characters using the visible spectroscopy coupled with NIR spectroscopy and it is feasible to use visible-NIR technology to investigate the surface characteristics of natural polymers treated with electroless copper plating.
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Cobre , Espectroscopia de Luz Próxima ao Infravermelho , Madeira , Análise de Componente PrincipalRESUMO
As one of the most important decorative materials for the modern household products, decorative papers impregnated with melamine not only have better decorative performance, but also could greatly improve the surface properties of materials. However, the appearance quality (such as color-difference evaluation and control) of decorative papers, as an important index for the surface quality of decorative paper, has been a puzzle for manufacturers and consumers. Nowadays, human eye is used to discriminate whether there exist color difference in the factory, which is not only of low efficiency but also prone to bring subjective error. Thus, it is of great significance to find an effective method in order to realize the fast recognition and classification of the decorative papers. In the present study, the visible spectroscopy coupled with principal component analysis (PCA) was used for the pattern recognition of decorative papers with different visual characteristics to investigate the feasibility of visible spectroscopy to rapidly recognize the types of decorative papers. The results showed that the correlation between visible spectroscopy and visual characteristics (L*, a* and b*) was significant, and the correlation coefficients wereup to 0.85 and some was even more than 0. 99, which might suggest that the visible spectroscopy reflected some information about visual characteristics on the surface of decorative papers. When using the visible spectroscopy coupled with PCA to recognize the types of decorative papers, the accuracy reached 94%-100%, which might suggest that the visible spectroscopy was a very potential new method for the rapid, objective and accurate recognition of decorative papers with different visual characteristics.
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Surface glossiness is one of the important visual appearance parameters of natural polymer material (wood) and its related products. To realize the fast measurement of natural polymer material surface glossiness is of great significance to the online quality control and assessment of its surface. In order to broaden the application of near infrared (NIR) spectroscopy in the field of polymer material surface quality control and realize the feasibility of NIR as a fast measurement of surface glossiness, the NIR combined with partial least squares (PLS) analysis were used to analyse the correlations of natural polymer material wood surface glossiness between the NIR predicted and lab measured, and then to investigate the feasibility of NIR to rapidly predict the surface glossiness of natural polymer material wood. The results showed that the wood NIR diffuse reflectance spectroscopy regularly varied with the different wood surface glossiness, from which we can concluded that the NIR spectrums reflected the information of wood surface glossiness. The correlation coefficients of surface glossiness between the PLS models predicted and lab measured were up to 0.90. Additionally, by changing the degree between the fiber and sample surface, we collected the different wood NIR spectrums, the accuracy of NIR surface glossiness models based on these NIR spectrums had not significantly improved, and models based on the NIR spectrums collected by the 90 degree between the fiber and sample surface performed better.
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Espectroscopia de Luz Próxima ao Infravermelho , Madeira/análise , Análise dos Mínimos Quadrados , Polímeros , Controle de Qualidade , Propriedades de SuperfícieRESUMO
Ultrasmall copper nanoclusters have recently emerged as promising photocatalysts for organic synthesis, owing to their exceptional light absorption ability and large surface areas for efficient interactions with substrates. Despite significant advances in cluster-based visible-light photocatalysis, the types of organic transformations that copper nanoclusters can catalyze remain limited to date. Herein, we report a structurally well-defined anionic Cu40 nanocluster that emits in the second near-infrared region (NIR-II, 1000-1700 nm) after photoexcitation and can conduct single-electron transfer with fluoroalkyl iodides without the need for external ligand activation. This photoredox-active copper nanocluster efficiently catalyzes the three-component radical couplings of alkenes, fluoroalkyl iodides, and trimethylsilyl cyanide under blue-LED irradiation at room temperature. A variety of fluorine-containing electrophiles and a cyanide nucleophile can be added onto an array of alkenes, including styrenes and aliphatic olefins. Our current work demonstrates the viability of using readily accessible metal nanoclusters to establish photocatalytic systems with a high degree of practicality and reaction complexity.
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Morpholines are widespread in many biologically and catalytically active agents, thus being an important aim of pharmaceutical and synthetic chemists. However, efficient strategies for the catalytic asymmetric synthesis of chiral morpholines bearing crowded stereogenic centers still remain elusive. Herein, we disclose a Cu-catalyzed asymmetric propargylic amination/desymmetrization strategy to help resolve this challenge. As a result, two kinds of structurally various chiral morpholines bearing rich functional groups and N-α-quaternary stereocenters were produced with high efficiency and selectivity (42 examples, up to 91 % yield, 97:3 er and > 19:1 dr). In addition, a series of transformations were performed to demonstrate the synthetic utility of this methodology. In particular, a hit compound for new antitumor drugs was identified through cellular evaluation. Furthermore, mechanistic investigations reveal that, hydrogen bonding in the key copper-allenylidene intermediate together with π-π stacking aids remote enantioinduction.
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In order to investigate the feasibility of visible/Near Infrared(Vis-NIR)spectroscopy to predict the surface roughness of natural polymer material(wood) as a non-contact measurement method, the correlations between Vis-NIR spectroscopy and surface roughness measured by contact(stylus) instruments from three different sections of wood samples were analyzed. The results showed that the surface roughness parameters, arithmetical mean deviation of profile (Ra), ten-point height of irregularities (Rz) and the maximum height of profile (Ry), of wood samples were successfully predicted by using Vis-NIR (400-2,500 nm) models from the three sections of the samples. The correlations between values measured by the stylus instruments and the values predicted by the models were good. The correlation coefficients of Rz reached up to 0.92. Compared to the models based on the Vis-NIR from the radial section and tangential section of the samples, the predictive effect of the model based on cross section was the best. The correlation coefficients between the values measured by the stylus instruments and the values predicted by the models based on different spectrum wavelength range, 400-780, 780-1,100, 1,100-2 500, 780-2,500 and 400-2,500 nm, were generally above 0.80. The prediction results of the model based on spectrum wavelength range 400-2,500 nm was better than the models based on the other spectrum wavelength ranges. The results showed that the predictive effect was not improved by pretreatment of the spectrum. It is proposed to use the original spectrum to predict the surface roughness of natural polymer material.
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Polímeros/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Madeira/química , Previsões , Propriedades de SuperfícieRESUMO
Transition metal-catalyzed cycloaddition has been established as a powerful tool for heterocycle synthesis. Despite impressive advances, the exploitation of new catalysis strategies and systems is still highly significant to enrich the heterocycle family. Herein, we disclosed a cooperative catalysis system merging an achiral Pd catalyst and a chiral Co catalyst for the asymmetric [4+2] cycloaddition between vinyl benzoxazinones and N-acylpyrazoles. Chiral tetrahydroquinolines bearing two contiguous, unusual cis-configured stereocenters were produced in high yields and enantio- and diastereoselectivities. The pyrazole directing group can be easily converted into many other functional groups, thus demonstrating the flexibility of the present methodology.
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PURPOSE: This pilot study aimed to evaluate the feasibility and effect of a guided self-disclosure intervention (GSDI) promoting benefit finding (BF) for breast cancer patients. METHODS: A total of 40 women with breast cancer were randomized either to a GSDI group, which included a 6-session face-to-face self-disclosure intervention, or to a control group. The Benefit Finding Scale (BFS) was used to measure BF, the Distress Disclosure Index (DDI) was used to measure self-disclosure, and the Impact of Event Scale-Revised (IES-R) was used to measure cognitive reappraisal. The outcomes were evaluated at baseline and the 3rd and 6th months. RESULTS: The GSDI group had more satisfaction (t = 2.35, P = .02) than the control group and had significant group effects of higher BF (t = 2.214, P = .03) and a lower avoidance of the IES-R (t = -2.353, P = .024) at the 3rd month. There was a significant difference of BF (t = 2.036, P = .049) between the two groups at the 6th month, and other outcomes were not significant (P > .05). Intention-to treat (ITT) analysis showed significant time effects for all outcomes (P < .05); there were slightly significant time × group effects for BF (F = 4.15, P = .052) and disclosure (F = 2.719, P = .090). There were no time × group effects for the other outcomes (all P > .05). CONCLUSION: This study suggests that the GSDI intervention may be feasible in the clinic and might improve BF for breast cancer patients. However, future research needs to further refine the intervention and expand the sample to carry out a full-scale randomized controlled trial.
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Neoplasias da Mama/psicologia , Otimismo/psicologia , Intervenção Psicossocial/métodos , Adaptação Psicológica , Adulto , Povo Asiático , Neoplasias da Mama/enfermagem , Revelação , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Angústia PsicológicaRESUMO
Catalytic asymmetric cycloadditions via transition-metal-containing dipolar intermediates are a powerful tool for synthesizing chiral heterocycles. However, within the field of palladium catalysis, compared with the well-developed normal electron-demand cycloadditions with electrophilic dipolarophiles, a general strategy for inverse electron-demand ones with nucleophilic dipolarophiles remains elusive, due to the inherent linear selectivity in the key palladium-catalyzed intermolecular allylations. Herein, based on the switched regioselectivity of iridium-catalyzed allylations, we achieved two asymmetric [4+2] cycloadditions of vinyl aminoalcohols with aldehydes and ß,γ-unsaturated ketones through synergetic iridium and amine catalysis. The activation of vinyl aminoalcohols by iridium catalysts and carbonyls by amine catalysts provide a foundation for the subsequent asymmetric [4+2] cycloadditions of the resulting iridium-containing 1,4-dipoles and (di)enamine dipolarophiles. The former provides a straightforward route to a diverse set of enantio-enriched hydroquinolines bearing chiral quaternary stereocenters, and the later represent an enantio- and diastereodivergent synthesis of chiral hydroquinolines.
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A copper-catalyzed Friedel-Crafts propargylation/hydroamination/aromatization sequence is described. In the presence of a catalytic amount of CuI, this sequential reaction can convert ethynyl benzoxazinanones and indoles into a diverse set of 3,3'-biindoles with high efficiency and selectivity. Moreover, the synthesis of other indole-heteroaryl molecules and the catalytic asymmetric formation of axially chiral 3,3'-biindoles are demonstrated.
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A novel copper-catalyzed decarboxylative cyclization of ethynyl benzoxazinanones with P(O)H compounds has been developed. This protocol leads to a series of 2-phosphorylmethyl indoles with high efficiency and selectivity (up to 99% yield) through tandem C-P/C-N bond formation under mild conditions.