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1.
BMC Public Health ; 24(1): 1459, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822310

RESUMO

OBJECTIVE: This study aimed to develop and validate the Salt Reduction Behavior Scale (SRBS) to measure the behavior of hypertensive Chinese individuals in adhering to salt reduction practices. METHODS: The SRBS was constructed based on the Health Belief Model, consisting of five constructs: knowledge, perceived severity, perceived benefits, perceived barriers, and cues to action. Data were collected from 2,082 hypertensive patients in Beijing, China, who completed a questionnaire administered through an online platform. Kaiser-Meyer-Olkin (KMO) test was used to assess the adequacy of the sample and the Bartlett's test of sphericity to examine the factorability of the dataset. Confirmatory Factor Analysis (CFA) was used to assess the structural validity and reliability of the SRBS. RESULTS: The KMO analysis yielded a notably elevated value of 0.95, indicating that the data was highly suitable for Exploratory Factor Analysis (EFA). Bartlett's test of sphericity yielded a statistically significant test statistic (P < 0.001). The 32-item SRB questionnaire demonstrated strong internal consistency with a Cronbach's alpha coefficient of 0.923. A second-order Confirmatory Factor Analysis (CFA) revealed that, after removing the unrelated construct of barriers, SRB could be represented by four sub-constructs: knowledge, severity, benefits, and action. The final version of the SRBS consists of 21 items. These items displayed high factor loadings, indicating a strong relationship between the items and their respective sub-constructs. The discriminant validity analysis revealed that the SRBS sub-constructs were distinct from each other. The SRBS scores were positively correlated with self-reported salt reduction practices. This demonstrates that individuals with higher SRBS scores were more likely to engage in actual salt reduction behaviors, indicating concurrent validity. CONCLUSION: The results illustrate that the Salt Reduction Behavior Scale is a robust and comprehensive instrument for assessing salt reduction behavior among hypertensive Chinese individuals. The scale's specific sub-constructs provide a detailed understanding of their knowledge, attitudes, and practices related to salt consumption. Healthcare professionals and policymakers can utilize this tool to tailor interventions and educational programs to encourage healthier dietary habits, thereby reducing the risk of cardiovascular diseases in China.


Assuntos
Hipertensão , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Hipertensão/psicologia , Inquéritos e Questionários/normas , China , Reprodutibilidade dos Testes , Análise Fatorial , Adulto , Psicometria , Conhecimentos, Atitudes e Prática em Saúde , Comportamentos Relacionados com a Saúde , Idoso , Cloreto de Sódio na Dieta , Modelo de Crenças de Saúde , População do Leste Asiático
2.
Sensors (Basel) ; 24(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38474944

RESUMO

In this paper, we introduce a novel panoptic segmentation method called the Mask-Pyramid Network. Existing Mask RCNN-based methods first generate a large number of box proposals and then filter them at each feature level, which requires a lot of computational resources, while most of the box proposals are suppressed and discarded in the Non-Maximum Suppression process. Additionally, for panoptic segmentation, it is a problem to properly fuse the semantic segmentation results with the Mask RCNN-produced instance segmentation results. To address these issues, we propose a new mask pyramid mechanism to distinguish objects and generate much fewer proposals by referring to existing segmented masks, so as to reduce computing resource consumption. The Mask-Pyramid Network generates object proposals and predicts masks from larger to smaller sizes. It records the pixel area occupied by the larger object masks, and then only generates proposals on the unoccupied areas. Each object mask is represented as a H × W × 1 logit, which fits well in format with the semantic segmentation logits. By applying SoftMax to the concatenated semantic and instance segmentation logits, it is easy and natural to fuse both segmentation results. We empirically demonstrate that the proposed Mask-Pyramid Network achieves comparable accuracy performance on the Cityscapes and COCO datasets. Furthermore, we demonstrate the computational efficiency of the proposed method and obtain competitive results.

3.
Br J Cancer ; 128(7): 1377-1390, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36681728

RESUMO

BACKGROUND: Castration-resistant prostate cancer (CRPC) is refractory to hormone treatment. This study aims to explore the effect and underlying mechanisms of immunoproteasome inhibition, a novel immunotherapy, on the progression of CRPC. METHODS: The immunoproteasome subunit LMP7 was silenced by using gene knockout or inhibited by the epoxyketone inhibitor ONX 0914 in a mouse CRPC tumour graft model and in interferon-γ-pretreated human CRPC cell lines in vitro. RESULTS: CRPC tissues reveal a significant "tumour-elicited" Th17-type inflammatory response which induces immunoproteasome subunit expression. LMP7 deficiency in host mice or in CRPC tumour grafts had no effect on the "tumour-elicited" Th17-type inflammatory response and tumour progression. However, the selective LMP7 inhibitor ONX 0914 strongly suppressed the "tumour-elicited" Th17-type inflammatory response and CRPC tumour progression. Treatment of wild-type mice receiving LMP7-deficient CRPC tumour grafts with ONX 0914 further suggested that immunoproteasome inhibition prevents CRPC progression through suppressing IL-17-induced angiogenesis and epithelial-mesenchymal transition via inactivation of COX-2/VEGF-A signalling and ß-catenin/Snail signalling. Treatment of LMP7-deficient mice receiving wild-type CRPC tumour grafts with ONX 0914 and inhibition of LMP7 in PC3 and 22Rv.1 cells with ONX 0914 showed that immunoproteasome inhibition also prevents CRPC progression through inducing CRPC cell apoptosis via activation of the unfolded protein response. CONCLUSIONS: We define a critical role of the immunoproteasome in CRPC and propose immunoproteasome inhibition as a promising therapeutic approach to suppress CRPC progression.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Masculino , Camundongos , Humanos , Animais , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Transdução de Sinais , Interferon gama , Modelos Animais de Doenças , Complexo de Endopeptidases do Proteassoma/metabolismo
4.
Mol Genet Genomics ; 298(6): 1301-1308, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37498359

RESUMO

OBJECTIVES: Previous studies suggested that the Y-chromosome haplogroups O2-N6-B451-AM01756 and O1a-M119 are two founder lineages of proto-Austronesians at about five thousand years ago. The objective of this study was to investigate the formation of proto-Austronesians from the perspective of the paternal gene pool. MATERIALS AND METHODS: In this study, we developed a highly evised phylogenetic tree with age estimates for haplogroup O2-N6 and early branches of O1a-M119 (M110, F1036, and F819). In addition, we also explored the geographical distribution of eight sub-branches of O2-N6 and O1a-M119, and spatial autocorrelation analysis was conducted for each sub-branch. RESULTS: The paternal lineage combination of proto-Austronesians is a small subset of a diverse gene pool of populations from the mainland of East Asia. The distribution map and results of the spatial autocorrelation analysis suggested that the eastern coastal region of northern China is likely the source of lineage O2-N6 while the coastal region of southeastern China is likely the diffusion center of early branches of O1a-M119. We developed an evolutionary diagram for Austronesians and their ancestors in the past 18,000 years. DISCUSSION: We proposed that the millet farming community in North China is the common ancestor group of the Austronesians and the Han people, while the diverse ancient people in the southeast coastal areas of East Asia form the common ancestor group of the Austronesians and the East Asian mainland population. The demographic history of multiple ancestral groups of the most recent common ancestor group itself in the more ancient period is helpful to understand the deep roots of the genetic components and cultural traditions of Austronesians.


Assuntos
Cromossomos Humanos Y , Genética Populacional , Humanos , Filogeografia , Filogenia , Haplótipos/genética , Cromossomos Humanos Y/genética , Ásia Oriental
5.
J Org Chem ; 88(18): 13327-13330, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37615542

RESUMO

Salicylaldehyde works as an efficient photocatalyst for the intermolecular transalkylation of phthalimide. The well-designed dimethyl N-hydroxyphthalimide ester proves to be a good alkylation reagent. It inhibits the competing intramolecular alkylation of alkylating reagent, enabling the site-specific synthesis of N-substituted phthalimide.

6.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1463-1482, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37005834

RESUMO

Dolomiaea plants are perennial herbs in the Asteraceae family with a long medicinal history. They are rich in chemical constituents, mainly including sesquiterpenes, phenylpropanoids, triterpenes, and steroids. The extracts and chemical constituents of Dolomiaea plants have various pharmacological effects, such as anti-inflammatory, antibacterial, antitumor, anti-gastric ulcer, hepatoprotective and choleretic effects. However, there are few reports on Dolomiaea plants. This study systematically reviewed the research progress on the chemical constituents and pharmacological effects of Dolomiaea plants to provide references for the further development and research of Dolomiaea plants.


Assuntos
Asteraceae , Sesquiterpenos , Triterpenos , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Anti-Inflamatórios , Compostos Fitoquímicos/farmacologia
7.
Biomed Chromatogr ; 36(6): e5357, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35191054

RESUMO

Sophorae tonkinensis Radix et Rhizoma (S. tonkinensis) has been recorded as a 'poisonous' Chinese herbal medicine in Chinese Pharmacopoeia 2020. The clinical reaction reports of S. tonkinensis indicated its neurotoxicity; however, there still exists dispute about its toxic substances. At present, no report is available on the blood and brain prototype research of S. tonkinensis. Most studies focused on alkaloids and less on other compounds. Moreover, the constituents absorbed into the blood and brain have been rarely investigated so far. This study established a rapid and efficient qualitative analysis method using UPLC-Q-TOF-MSE to characterize the ingredients of S. tonkinensis and those entering into the rat's body after oral administration. A total of 91 compounds were identified in S. tonkinensis, of which 28 were confirmed by the standards. In addition, 30 and 19 prototypes were also first identified in the rat's blood and brain, respectively. It was found that most flavonoids, except alkaloids, were detected in the rat's body and distributed in the cerebrospinal fluid, suggesting that flavonoids may be one of the important toxic or effective substances of S. tonkinensis. This finding provides new clues and data for clarifying the toxicity or efficacy of this medicinal plant.


Assuntos
Alcaloides , Medicamentos de Ervas Chinesas , Sophora , Alcaloides/química , Animais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Flavonoides/análise , Ratos , Rizoma/química , Sophora/química
8.
Ecotoxicol Environ Saf ; 248: 114341, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36442401

RESUMO

Radiation-induced intestinal damage (RIID) is a serious disease with limited effective treatment. Nuclear explosion, nuclear release, nuclear application and especially radiation therapy are all highly likely to cause radioactive intestinal damage. The intestinal microecology is an organic whole with a symbiotic relationship formed by the interaction between a relatively stable microbial community living in the intestinal tract and the host. Imbalance and disorders of intestinal microecology are related to the occurrence and development of multiple systemic diseases, especially intestinal diseases. Increasing evidence indicates that the gut microbiota and its metabolites play an important role in the pathogenesis and prevention of RIID. Radiation leads to gut microbiota imbalance, including a decrease in the number of beneficial bacteria and an increase in the number of harmful bacteria that cause RIID. In this review, we describe the pathological mechanisms of RIID, the changes in intestinal microbiota, the metabolites induced by radiation, and their mechanism in RIID. Finally, the mechanisms of various methods for regulating the microbiota in the treatment of RIID are summarized.


Assuntos
Microbioma Gastrointestinal , Microbiota , Intestinos
9.
Chem Biodivers ; 19(3): e202101013, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35229460

RESUMO

Three new monoterpene alkaloids, delavatines C-E (1-3), along with five known ones (4-8), were separated from the whole plants of Incarvillea delavayi. All compounds were deduced by interpretation of comprehensive NMR spectral data and X-Ray single crystal diffraction, in combination with a quantum chemical calculation of NMR chemical shift coupled with an advanced statistical procedure DP4+. Compounds 1-8 were assessed NO suppressive effect in LPS-stimulated BV2 microglia cells. Compounds 2, 3, 6, and 8 exhibited significant inhibition against NO production in LPS-induced BV2 cells with IC50 values of 25.62, 17.29, 19.94 and 23.88 µM, stronger than or comparable to the positive control (AG) with IC50 value of 26.13 µM.


Assuntos
Alcaloides , Bignoniaceae , Alcaloides/farmacologia , Bignoniaceae/química , Lipopolissacarídeos/farmacologia , Microglia , Monoterpenos/farmacologia , Óxido Nítrico
10.
J Environ Manage ; 323: 116232, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36261982

RESUMO

Feed-in tariff (FIT) and renewable portfolio standard (RPS) policies have been implemented to facilitate wind and solar power technologies with the aim of achieving sustainable development in power system. It is essential to study how efficient these policies are in accelerating technical progress and how efficient the power system is in balancing development and environmental protection. Dynamic network data envelopment analysis and the global Malmquist productivity index are first employed to study the environmental efficiency and technical progress, after which a dynamic spatial Durbin model is applied to analyze the impact of policies on technical progress. The results reveal that both FIT and RPS lead to technical progress which is the main driving force in environmental efficiency improvement, but that RPS performs better than FIT. From a spatial perspective, the adjacent regions usually show similar characteristics in technical progress. Therefore, future policy design should carefully consider the regional agglomeration effects and should effectively strengthen the implementation of RPS policy.


Assuntos
Conservação dos Recursos Naturais , Eficiência , Tecnologia , Políticas , China
11.
Zhongguo Zhong Yao Za Zhi ; 47(10): 2759-2766, 2022 May.
Artigo em Zh | MEDLINE | ID: mdl-35718496

RESUMO

Based on network pharmacology and molecular docking, the mechanism of danshensu and tetramethylpyrazine, the main active components of Shenxiong Glucose Injection(SGI), against myocardial ischemia-reperfusion injury(MIRI) was explored. Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP), GeneCards, and Online Mendelian Inheri-tance in Man(OMIM) were used to search the targets of the active components and the disease, and the common targets were screened. The "drug-component-disease-target" network was constructed by Cytoscape, and the protein-protein interaction network was established by STRING, followed by Gene Ontology(GO) term and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment by R software. AutoDock Vina was employed for the molecular docking between active components and core targets. A total of 15 potential targets of danshensu and tetramethylpyrazine against MIRI were screened out, involving the major GO terms of cyclooxyge-nase pathway, extracellular matrix binding, and antioxidant activity, and the main pathways of platelet activation and regulation of lipolysis in adipocytes. Danshensu and tetramethylpyrazine can form stable conformations with core targets prostaglandin G/H synthase 2(PTGS2), vascular endothelial growth factor A(VEGFA), and acetylcholinesterase(ACHE) with low binding energy. This study reflects the multi-component, multi-target, multi-pathway, and synergistic action characteristics of SGI, which provides a theoretical re-ference for further clarifying the anti-MIRI mechanism of SGI.


Assuntos
Medicamentos de Ervas Chinesas , Traumatismo por Reperfusão Miocárdica , Acetilcolinesterase , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fator A de Crescimento do Endotélio Vascular
12.
Zhongguo Zhong Yao Za Zhi ; 47(3): 593-602, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35178941

RESUMO

Chinese medicine processing is a procedure to process medicinal materials under the guidance of traditional Chinese medicine(TCM) theories by using unique methods in China. The medicinal materials can only be used clinically after proper processing. With the development of the modernization of TCM, it is difficult to solve the problems in the inheritance, development, and internationalization of Chinese medicine processing. Metabonomics, a new omics technology developed at the end of the last century, is used to infer the physiological or pathological conditions of the organism with the methods such as NMR and LC-MS via investigating the changes in endogenous small molecule metabolic network after the organism is stimulated by external environment. Metabonomics coincides with the holistic view of TCM because it displays the characteristics of integrity, comprehensiveness, and dynamics, and it has been widely applied in the field of Chinese medicine processing in recent years. This study summarized the application of metabonomics in the processing mechanism and quality control of Chinese medicine processing and prospected the development of this technology in the field of Chinese medicine processing.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Cromatografia Líquida , Espectrometria de Massas , Metabolômica/métodos , Controle de Qualidade
13.
Zhongguo Zhong Yao Za Zhi ; 47(2): 367-375, 2022 Jan.
Artigo em Zh | MEDLINE | ID: mdl-35178978

RESUMO

Syndrome is a nonlinear "internal-excess external-deficiency", "dynamic spatial-temporal" and "multi-dimensional" complex system and thus only by using a versatile method can the connotation be expounded. Metabonomics, which is dynamic, holistic, and systematic, is consistent with the overall mode of traditional Chinese medicine(TCM)(holistic view and syndrome differentiation and treatment). Therefore, metabonomics is very important for the research on the differentiation, material basis, and metabolic pathways of syndromes, and efficacy on syndromes. This study reviewed the application of metabonomics in the study of TCM syndromes in recent years, which is expected to objectify the research on TCM syndromes.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Metabolômica , Síndrome
14.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(12): 1311-1312, 2022 Dec 15.
Artigo em Zh | MEDLINE | ID: mdl-36544409

RESUMO

This article reports a case of incomplete Kawasaki disease with no response to intravenous immunoglobulin (IVIG). A girl, aged 1 year, had the symptoms of fever, rash, finger desquamation, and coronary artery ectasia. She still had fever at 36 hours after the first dose of IVIG treatment, and her temperature returned to normal after the second dose of IVIG treatment. The follow-up after 1 month showed that the coronary artery diameter returned to normal. This article summarizes the experience in the treatment of incomplete Kawasaki disease with no response to IVIG in order to reduce the incidence of coronary artery damage.


Assuntos
Aneurisma Coronário , Síndrome de Linfonodos Mucocutâneos , Humanos , Feminino , Lactente , Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Febre , Aneurisma Coronário/etiologia , Estudos Retrospectivos
15.
Mol Plant Microbe Interact ; 34(3): 240-254, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33507814

RESUMO

Verticillium wilt is a vascular disease causing tremendous damage to cotton production worldwide. However, our knowledge of the mechanisms of cotton resistance or susceptibility to this disease is very limited. In this study, we compared the defense transcriptomes of cotton (Gossypium hirsutum) cultivars Shidalukang 1 (Verticillium dahliae resistant, HR) and Junmian 1 (V. dahliae susceptible, HS) before and after V. dahliae infection, identified hub genes of the network associated with responses to V. dahliae infection, and functionally characterized one of the hub genes involved in biosynthesis of lignin and phenolics. We identified 6,831 differentially expressed genes (DEGs) between the basal transcriptomes of HR and HS; 3,685 and 3,239 of these DEGs were induced in HR and HS, respectively, at different time points after V. dahliae infection. KEGG pathway analysis indicated that DEGs were enriched for genes involved in lignin biosynthesis. In all, 23 hub genes were identified based on a weighted gene coexpression network analysis of the 6,831 DEGs and their expression profiles at different time points after V. dahliae infection. Knockdown of Gh4CL30, one of the hub genes related to the lignin biosynthesis pathway, by virus-induced gene silencing, led to a decreased content of flavonoids, lignin, and S monomer but an increased content of G monomer, G/S lignin monomer, caffeic acid, and ferulic acid, and enhanced cotton resistance to V. dahliae. These results suggest that Gh4CL30 is a key gene modulating the outputs of different branches of the lignin biosynthesis pathway, and provide new insights into cotton resistance to V. dahliae.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Resistência à Doença , Gossypium , Lignina , Fenóis , Proteínas de Plantas , Verticillium , Ascomicetos/fisiologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Gossypium/química , Gossypium/genética , Gossypium/metabolismo , Gossypium/microbiologia , Lignina/genética , Fenóis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Verticillium/metabolismo
16.
Herz ; 46(3): 262-268, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32435839

RESUMO

BACKGROUND: The optimal coronary revascularization strategy for patients with unprotected left main coronary artery (ULMCA) disease and left ventricular systolic dysfunction (LVSD) remains uncertain. The purpose of this study was to evaluate the clinical outcomes after percutaneous coronary intervention (PCI) with a drug-eluting stent (DES) versus coronary artery bypass grafting (CABG) in patients with ULMCA disease with or without LVSD. METHODS: A total of 984 patients with ULMCA disease who received a DES (n = 511) or underwent CABG (n = 473) were included in this study. We retrospectively analyzed the clinical parameters and outcomes of ULMCA disease patients with different left ventricular ejection fraction levels. RESULTS: There were no significant differences in major adverse cardiac and cerebral events, all-cause death, cardiac death, myocardial infarction, or stroke between the CABG and DES groups with or without LVSD. The rate of target vessel revascularization was significantly higher with DES compared with CABG in patients without LVSD; however, the difference was not significant between the mild LVSD and severe LVSD groups. CONCLUSION: For patients with ULMCA disease and LVSD, there was no significant difference between DES and CABG in terms of efficacy and safety. Treatment with DES was an acceptable alternative to CABG.


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Doença da Artéria Coronariana/cirurgia , Humanos , Estudos Retrospectivos , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda
17.
J Asian Nat Prod Res ; 23(11): 1100-1106, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33345615

RESUMO

A new 4-hydroxy-α-pyrone, namely capsulactone (1), was isolated from an endophytic fungus Penicillium capsulatum XL027 obtained from the leaves of Panax notoginseng. The structure and absolute configuration of 1 were elucidated through a combination of spectroscopic data and computed methods, as well as by comparison with literature data. Compound 1 exhibited weak activity against methicinllin-resistant Staphylococcus aureus with an MIC value of 100 µg/ml.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Penicillium , Antibacterianos/farmacologia , Fungos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pironas/farmacologia
18.
Nano Lett ; 20(9): 6815-6823, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32786952

RESUMO

Spin-dependent transport at heavy metal/magnetic insulator interfaces is at the origin of many phenomena at the forefront of spintronics research. A proper quantification of the different interfacial spin conductances is crucial for many applications. Here, we report the first measurement of the spin Hall magnetoresistance (SMR) of Pt on a purely ferromagnetic insulator (EuS). We perform SMR measurements in a wide range of temperatures and fit the results by using a microscopic model. From this fitting procedure, we obtain the temperature dependence of the spin conductances (Gs, Gr, and Gi), disentangling the contribution of field-like torque (Gi), damping-like torque (Gr), and spin-flip scattering (Gs). An interfacial exchange field of the order of 1 meV acting upon the conduction electrons of Pt can be estimated from Gi, which is at least three times larger than Gr below the Curie temperature. Our work provides an easy method to quantify this interfacial spin-splitting field, which plays a key role in emerging fields such as superconducting spintronics and caloritronics as well as topological quantum computation.

19.
BMC Plant Biol ; 20(1): 125, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32293290

RESUMO

BACKGROUND: The function of 4-coumarate-CoA ligases (4CL) under abiotic stresses has been studied in plants, however, limited is known about the 4CL genes in cotton (G. hirsutum L.) and their roles in response to drought stress. RESULTS: We performed genome-wide identification of the 4CL genes in G. hirsutum and investigated the expression profiles of the identified genes in various cotton tissues and in response to stress conditions with an aim to identify 4CL gene(s) associated with drought tolerance. We identified 34 putative 4CL genes in G. hirsutum that were clustered into three classes. Genes of the same class usually share a similar gene structure and motif composition. Many cis-elements related to stress and phytohormone responses were found in the promoters of the Gh4CL genes. Of the 34 Gh4CL genes, 26 were induced by at least one abiotic stress and 10 (including Gh4CL7) were up-regulated under the polyethylene glycol (PEG) simulated drought stress conditions. Virus-induced gene silencing (VIGS) in cotton and overexpression (OE) in Arabidopsis thaliana were applied to investigate the biological function of Gh4CL7 in drought tolerance. The Gh4CL7-silencing cotton plants showed more sensitive to drought stress, probably due to decreased relative water content (RWC), chlorophyll content and antioxidative enzyme activity, increased stomatal aperture, and the contents of malondialdehyde (MDA) and hydrogen peroxide (H2O2). Arabidopsis lines overexpressing Gh4CL7, however, were more tolerant to drought treatment, which was associated with improved antioxidative enzyme activity, reduced accumulation of MDA and H2O2 and up-regulated stress-related genes under the drought stress conditions. In addition, compared to their respective controls, the Gh4CL7-silencing cotton plants and the Gh4CL7-overexpressing Arabidopsis lines had a ~ 20% reduction and a ~ 10% increase in lignin content, respectively. The expression levels of genes related to lignin biosynthesis, including PAL, CCoAOMT, COMT, CCR and CAD, were lower in Gh4CL7-silencing plants than in controls. Taken together, these results demonstrated that Gh4CL7 could positively respond to drought stress and therefore might be a candidate gene for improvement of drought tolerance in cotton. CONCLUSION: We characterized the 4CL gene family in upland cotton and revealed a role of Gh4CL7 in lignin biosynthesis and drought tolerance.


Assuntos
Coenzima A Ligases/genética , Secas , Gossypium/fisiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/fisiologia , Coenzima A Ligases/metabolismo , Gossypium/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética
20.
Nano Lett ; 19(9): 6330-6337, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31378061

RESUMO

We present a theory of the spin Hall magnetoresistance of metals in contact with magnetic insulators. We express the spin mixing conductances, which govern the phenomenology of the effect, in terms of the microscopic parameters of the interface and the spin-spin correlation functions of the local moments on the surface of the magnetic insulator. The magnetic-field and temperature dependence of the spin mixing conductances leads to a rich behavior of the resistance due to an interplay between the Hanle effect and the spin mixing at the interface. We describe an unusual negative magnetoresistance originating from a nonlocal Hanle effect. Our theory provides a useful tool for understanding the experiments on heavy metals in contact with magnetic insulators of different kinds, and it enables the spin Hall magnetoresistance effect to be used as a technique to study magnetism at interfaces.

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