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1.
Dev Genes Evol ; 226(1): 15-25, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26754485

RESUMO

The WRKY gene family, which encodes proteins in the regulation processes of diverse developmental stages, is one of the largest families of transcription factors in higher plants. In this study, by searching for interspecies gene colinearity (microsynteny) and dating the age distributions of duplicated genes, we found 35 chromosomal segments of subgroup I genes of WRKY family (WRKY I) in four Gramineae species (Brachypodium, rice, sorghum, and maize) formed eight orthologous groups. After a stepwise gene-by-gene reciprocal comparison of all the protein sequences in the WRKY I gene flanking areas, highly conserved regions of microsynteny were found in the four Gramineae species. Most gene pairs showed conserved orientation within syntenic genome regions. Furthermore, tandem duplication events played the leading role in gene expansion. Eventually, environmental selection pressure analysis indicated strong purifying selection for the WRKY I genes in Gramineae, which may have been followed by gene loss and rearrangement. The results presented in this study provide basic information of Gramineae WRKY I genes and form the foundation for future functional studies of these genes. High level of microsynteny in the four grass species provides further evidence that a large-scale genome duplication event predated speciation.


Assuntos
Duplicação Gênica , Proteínas de Plantas/genética , Poaceae/genética , Fatores de Transcrição/genética , Evolução Molecular , Genoma de Planta , Poaceae/classificação , Seleção Genética , Sintenia
2.
Artigo em Inglês | MEDLINE | ID: mdl-36078319

RESUMO

The assessment of regional economic security (RES) is mainly based on the theoretical ideas of political economy and marginalism, and the research areas are mainly concentrated in European and American countries/regions, especially Eastern Europe. Taking the Qinghai-Tibet Plateau in China as an example, this paper constructs a triple-dimensional analytical framework, resources, and environmental-economic foundation-driving forces, based on the institutional approach of economic geography, with the purpose of making up for the deficiency of the extant literature, which pays little attention to regional characteristics and the dynamic mechanism concerning RES, and to provide a tool to identify key factors affecting RES. This paper obtained the main conclusions as follows. (1) The index of the economic security in the Qinghai-Tibet Plateau is on the rise, and the difference at the level of RES among cities is significant but tends to decrease. (2) There is a significant spatial autocorrelation among cities in the Qinghai-Tibet Plateau in terms of RES. The high-value areas are concentrated along the southeast edge, and the low-value areas are concentrated in the central areas of the west. (3) Despite lower weight values, the weakness of the economic foundation and the fragility of the ecological environment has increasingly hampered the improvement of the economic security in the Qinghai-Tibet Plateau. In terms of driving forces, it is the support of the central government and aid programs of other provinces that contributes to its economic development.


Assuntos
Meio Ambiente , China , Cidades , Geografia , Tibet
3.
Artigo em Inglês | MEDLINE | ID: mdl-35010582

RESUMO

As an important cause of global warming, CO2 emissions have become a research hotspot in recent years. Industrial transfer impacts regional CO2 emissions and is related to the low-carbon development of regional industries. Taking the Beijing-Tianjin-Hebei region (BTH region) as an example, this study analysed industrial transfer's direct and indirect impacts on CO2 emissions based on a mediating model and two-way fixed effect panel regression. The results obtained indicate that industrial transfer-in has promoted CO2 emissions to a small extent, and the positive impact of industrial transfer-in on CO2 emissions wanes over time. Industrial transfer affects CO2 emissions by acting on the economic level, on population size, and on urbanisation level, but the indirect effect is weaker than the direct effect. Industrial transfer does not lead to technological upgrading, but the latter is an effective means of carbon emission reduction. Industrial transfer-in has shown a positive effect on CO2 emissions for most cities, but there are exceptions, such as Cangzhou. In the future, the BTH region should maintain coordinated development among cities and improve the cooperative innovation mechanism for energy conservation and emission reduction.


Assuntos
Poluição do Ar , Poluição do Ar/análise , Pequim , Dióxido de Carbono/análise , China , Cidades , Monitoramento Ambiental
4.
Materials (Basel) ; 14(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205499

RESUMO

The use of cement emulsified asphalt mortar (CA mortar) in the track structure of high-speed speed railways has been gaining considerations by many researchers due to its coupled merits of the strength of cement as well as the flexibility of asphalt material. The asphalt to cement ratio (A/C) and the compatibility among constituent materials are crucial to the properties of CA mortar. To improve the performance properties and application of CA mortar, it is imperative to have a broad understanding of the composition mechanisms and compatibility between constituent materials. This paper summarizes interesting research outcomes related to the composition and properties of CA mortar. The consumption of water by cement promotes the breakdown of emulsified asphalt, likewise, the adsorption of asphalt droplets on the surface of cement grains retards the hydration process of cement. An appropriate A/C is required for the cement hydration rate to match the speed of demulsification of asphalt emulsion. Depending on the type and properties for which the CA mortar is designed to possess, the A/C ranges from 0.2 to 0.6 for type 1 (CAM I), and 0.6 to 1.2 for type 2 (CAM II). This paper also discusses measures taken to improve performance properties, compatibility, the interaction between constituent materials of CA mortar, and the use of additives as a partial replacement of cement in CA mortar production. The current review also suggests areas of interest for future research studies. This paper is useful to those who aim to understand or study the composition mechanisms and performance properties of CA mortar.

5.
Materials (Basel) ; 13(8)2020 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-32290602

RESUMO

In order to improve the stability of air bubbles in fresh concrete, it is of great significance to have a better understanding of the mechanisms and main influencing factors of bubble stability. In the present review, the formation and collapse process of air bubbles in fresh concrete are essentially detailed; and the advances of major influencing factors of bubble stability are summarized. The results show that the surface tension of air-liquid interface exerts a huge impact on bubble stability by reducing surface free energy and Plateau drainage, as well as increasing the Gibbs surface elasticity. However, surface tension may not be the only determinant of bubble stability. Both the strength of bubble film and the diffusion rate of air through the membrane may also dominate bubble stability. The application of nano-silica is a current trend and plays a key role in ameliorating bubble stability. The foam stability could be increased by 6 times when the mass fraction of nano-particle reached 1.5%.

6.
Materials (Basel) ; 13(7)2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32260063

RESUMO

In order to solve the problems of the sudden loss of fluidity and low expansion rate of CAM I (cement asphalt mortar type I) in a construction site with high environmental temperature, this paper studies the effect of temperature on the fluidity, expansion ratio and pH value of CAM I. The mechanism of action was analyzed by IR (infrared spectrometry), SEM (scanning electron microscopy) and other test methods. The results showed that a high temperature accelerates aluminate formation in cement paste. Aluminate adsorbs emulsifiers leading to demulsification of emulsified asphalt, and wrapped on the surface of cement particles, this causes CAM I to lose its fluidity rapidly. The aluminum powder gasification reaction is inhibited, resulting in an abnormal change in the expansion ratio. Based on findings, the application of an appropriate amount of superplasticizers can effectively improve the workability and expansion characteristics of CAM I at a high temperature.

7.
J Genet ; 95(3): 691-704, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27659341

RESUMO

Multidrug and toxic compound extrusion (MATE) proteins are a group of secondary active transporters, which widely exist in all living organisms and play important role in the detoxication of endogenous secondary metabolites and exogenous agents. However, to date, no systematic and comprehensive study of this family is reported in maize. Here, a total of 49 MATE genes (ZmMATE) were identified and divided into seven groups by phylogenetic analysis. Conserved intro-exon structures and motif compositions were investigated in these genes. Results by gene locations indicated that these genes were unevenly distributed among all 10 chromosomes. Tandem and segmental duplications appeared to contribute to the expansion and evolution of this gene family. The Ka/Ks ratios suggested that the ZmMATE has undergone large-scale purifying selection on the maize genome. Interspecies microsynteny analysis revealed that there were independent gene duplication events of 10 ZmMATE. In addition, most maize MATE genes exhibited different expression profiles in diverse tissues and developmental stages. Sixteen MATE genes were chosen for further quantitative real-time polymerase chain reaction analysis showed differential expression patterns in response to aluminum treatment. These results provide a useful clue for future studies on the identification of MATE genes and functional analysis of MATE proteins in maize.


Assuntos
Alumínio/toxicidade , Cromossomos de Plantas/química , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Proteínas de Transporte de Cátions Orgânicos/genética , Proteínas de Plantas/genética , Zea mays/efeitos dos fármacos , Sequência de Aminoácidos , Sequência Conservada , Éxons , Perfilação da Expressão Gênica , Ontologia Genética , Íntrons , Anotação de Sequência Molecular , Família Multigênica , Motivos de Nucleotídeos , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Duplicações Segmentares Genômicas , Seleção Genética , Sintenia , Zea mays/classificação , Zea mays/genética
8.
World J Gastroenterol ; 10(16): 2406-8, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15285029

RESUMO

AIM: To investigate the expressions of E-cadherin and calretinin in exfoliated cells of serous effusions and evaluate their values in distinguishing malignant effusions from benign ones. METHODS: Fresh serous effusion specimens were centrifuged and exfoliated cells were collected. Cells were then processed with a standardized procedure, including paraformaldehyde fixation, BSA-PBS solution washing and smears preparation. E-cadherin and calretinin were detected by immunocytochemistry (ICC). RESULTS: In the exfoliated cells of serous effusions, most of carcinoma cells only expressed E-cadherin, and most of mesothelial cells only expressed calretinin, and benign cells (lymphocytes and granulocytes) did not express either of them. For E-cadherin, 85.7% (30/35) of malignant effusions and 8.1% (3/37) of benign fluids were ICC-positive (P<0.001). The sensitivity of E-cadherin ICC in the diagnosis of malignant effusions was 85.7%, specificity 91.9%, and diagnostic rate 88.9%. For calretinin, 94.6% (35/37) of benign effusions and 11.4% (4/35) of malignant effusions were ICC-positive (P<0.001). The sensitivity of calretinin ICC in the diagnosis of benign effusions was 94.6%, specificity 88.6%, and diagnostic rate 91.7%. For diagnosis of benign and malignant effusions by combining E-cadherin ICC and calretinin ICC, the specificities were up to 100% and 97.1%, respectively. CONCLUSION: E-cadherin ICC and calretinin ICC are sensitive and specific in differential diagnosis of benign and malignant serous effusion specimens and specificities are evidently improved when both markers are combined.


Assuntos
Líquido Ascítico/patologia , Caderinas/análise , Derrame Pleural Maligno/patologia , Proteína G de Ligação ao Cálcio S100/análise , Adolescente , Adulto , Idoso , Calbindina 2 , Membrana Celular/patologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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