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1.
Ecol Indic ; 150: 110221, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37265509

RESUMO

The global climate warming caused by urbanization has significantly affected the urban environment. Whilst land surface temperature (LST) is an important factor reflecting urban temperature, previous research on LST mostly focused on two-dimensional (2D) factors and rarely mentioned about the role of three-dimensional (3D) factors, particularly the LST variation characteristics of island cities. Therefore, this study examined the seasonal variation characteristics of urban LST by analyzing the impact of 2D and 3D urban morphology factors of different urban block types on LST in Xiamen Island. The main results are as follows. First, compact low layer (CL), a block type with a higher density of low-rise buildings, has a higher LST in any season. Under the same block density (BD), the higher the block average height (BH), the lower the LST. Second, among the 2D urban morphology factors, normalized difference vegetation index (NDVI) was the main factor for cities to reduce urban LST, especially in summer, while normalized difference built-up index (NDBI) was the opposite. Different from land cities, we found a positive correlation between modified normalized difference water body index (MNDWI) and LST in autumn and winter. Third, in the 3D urban morphology factors, sky view factor (SVF) was significantly positively correlated with LST, while building fluctuation (BF) was negatively correlated. The higher the SVF, the worse the radiation shielding effect between buildings. On the contrary, the higher the BF, the higher the building undulation, and the better the building radiation shielding. These findings should provide some quantitative insights for the future construction and planning of island cities, which can be used to improve the thermal environment of island cities and support the sustainable development of cities.

2.
PLoS Biol ; 15(12): e2002978, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29284002

RESUMO

Ion homeostasis is essential for plant growth and environmental adaptation, and maintaining ion homeostasis requires the precise regulation of various ion transporters, as well as correct root patterning. However, the mechanisms underlying these processes remain largely elusive. Here, we reported that a choline transporter gene, CTL1, controls ionome homeostasis by regulating the secretory trafficking of proteins required for plasmodesmata (PD) development, as well as the transport of some ion transporters. Map-based cloning studies revealed that CTL1 mutations alter the ion profile of Arabidopsis thaliana. We found that the phenotypes associated with these mutations are caused by a combination of PD defects and ion transporter misregulation. We also established that CTL1 is involved in regulating vesicle trafficking and is thus required for the trafficking of proteins essential for ion transport and PD development. Characterizing choline transporter-like 1 (CTL1) as a new regulator of protein sorting may enable researchers to understand not only ion homeostasis in plants but also vesicle trafficking in general.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/metabolismo , Glicosídeo Hidrolases/fisiologia , Transporte de Íons/genética , Proteínas de Membrana Transportadoras/fisiologia , Adenosina Trifosfatases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Proteínas de Transporte de Cátions/metabolismo , Clonagem Molecular , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Homeostase , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Mutação , Transporte Proteico , Simportadores/metabolismo
3.
EMBO Rep ; 19(10)2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30126927

RESUMO

Cryptochromes are photolyase-like photoreceptors. Arabidopsis CRY2 (cryptochrome 2) primarily mediates the photoperiodic regulation of floral initiation. CRY2 has been shown to promote FT (FLOWERING LOCUS T) mRNA expression in response to blue light by suppressing the degradation of the CO (CONSTANS) protein and activating CIB1 (CRY2-interacting bHLH1). Although CIB1 and CO are both transcriptional activators of FT, their relationship is unknown. Here, we show that CIB1 physically interacts with CO and promotes FT transcription in a CO-dependent manner. CRY2, CIB1, and CO form a protein complex in response to blue light to activate FT transcription, and the complex is regulated by the photoperiod and peaks at dusk along with higher FT expression. We also determined that CRY2 was recruited to the FT chromatin by CIB1 and CO and that all three proteins are bound to the same region within the FT promoter. Therefore, there is crosstalk between the CRY2-CO and CRY2-CIBs pathways, and CIB1 and CO act together to regulate FT transcription and flowering.


Assuntos
Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Criptocromos/genética , Proteínas de Ligação a DNA/genética , Flores/genética , Fatores de Transcrição/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Desoxirribodipirimidina Fotoliase/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Luz , Complexos Multiproteicos/genética , Fotoperíodo , Transcrição Gênica
4.
PLoS Genet ; 13(10): e1007086, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29084222

RESUMO

Arabidopsis thaliana high-affinity potassium transporter 1 (AtHKT1) limits the root-to-shoot sodium transportation and is believed to be essential for salt tolerance in A. thaliana. Nevertheless, natural accessions with 'weak allele' of AtHKT1, e.g. Tsu-1, are mainly distributed in saline areas and are more tolerant to salinity. These findings challenge the role of AtHKT1 in salt tolerance and call into question the involvement of AtHKT1 in salinity adaptation in A. thaliana. Here, we report that AtHKT1 indeed drives natural variation in the salt tolerance of A. thaliana and the coastal AtHKT1, so-called weak allele, is actually hyper-functional in reducing flowers sodium content upon salt stress. Our data showed that AtHKT1 positively contributes to saline adaptation in a linear manner. Forward and reverse genetics analysis established that the single AtHKT1 locus is responsible for the variation in the salinity adaptation between Col-0 and Tsu-1. Reciprocal grafting experiments revealed that shoot AtHKT1 determines the salt tolerance of Tsu-1, whereas root AtHKT1 primarily drives the salt tolerance of Col-0. Furthermore, evidence indicated that Tsu-1 AtHKT1 is highly expressed in stems and is more effective compared to Col-0 AtHKT1 at limiting sodium flow to the flowers. Such efficient retrieval of sodium to the reproductive organ endows Tsu-1 with stronger fertility compared to Col-0 upon salt stress, thus improving Tsu-1 adaptation to a coastal environment. To conclude, our data not only confirm the role of AtHKT1 in saline adaptation, but also sheds light on our understanding of the salt tolerance mechanisms in plants.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Transporte de Cátions/genética , Flores/genética , Tolerância ao Sal/genética , Sódio/metabolismo , Simportadores/genética , Alelos , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Salinidade , Cloreto de Sódio/metabolismo
5.
Plant Physiol ; 172(3): 1708-1719, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27702843

RESUMO

Rice is a major dietary source of the toxic metalloid arsenic (As). Reducing its accumulation in rice (Oryza sativa) grain is of critical importance to food safety. Rice roots take up arsenate and arsenite depending on the prevailing soil conditions. The first step of arsenate detoxification is its reduction to arsenite, but the enzyme(s) catalyzing this reaction in rice remains unknown. Here, we identify OsHAC1;1 and OsHAC1;2 as arsenate reductases in rice. OsHAC1;1 and OsHAC1;2 are able to complement an Escherichia coli mutant lacking the endogenous arsenate reductase and to reduce arsenate to arsenite. OsHAC1:1 and OsHAC1;2 are predominantly expressed in roots, with OsHAC1;1 being abundant in the epidermis, root hairs, and pericycle cells while OsHAC1;2 is abundant in the epidermis, outer layers of cortex, and endodermis cells. Expression of the two genes was induced by arsenate exposure. Knocking out OsHAC1;1 or OsHAC1;2 decreased the reduction of arsenate to arsenite in roots, reducing arsenite efflux to the external medium. Loss of arsenite efflux was also associated with increased As accumulation in shoots. Greater effects were observed in a double mutant of the two genes. In contrast, overexpression of either OsHAC1;1 or OsHAC1;2 increased arsenite efflux, reduced As accumulation, and enhanced arsenate tolerance. When grown under aerobic soil conditions, overexpression of either OsHAC1;1 or OsHAC1;2 also decreased As accumulation in rice grain, whereas grain As increased in the knockout mutants. We conclude that OsHAC1;1 and OsHAC1;2 are arsenate reductases that play an important role in restricting As accumulation in rice shoots and grain.


Assuntos
Arseniato Redutases/metabolismo , Arsênio/metabolismo , Oryza/enzimologia , Proteínas de Plantas/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Arsênio/toxicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Técnicas de Inativação de Genes , Especiação Genética , Proteínas de Fluorescência Verde/metabolismo , Mutação/genética , Oryza/efeitos dos fármacos , Oryza/genética , Oryza/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/metabolismo , Solo , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Xilema/efeitos dos fármacos , Xilema/metabolismo
6.
PLoS Biol ; 12(12): e1002009, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25464340

RESUMO

Inorganic arsenic is a carcinogen, and its ingestion through foods such as rice presents a significant risk to human health. Plants chemically reduce arsenate to arsenite. Using genome-wide association (GWA) mapping of loci controlling natural variation in arsenic accumulation in Arabidopsis thaliana allowed us to identify the arsenate reductase required for this reduction, which we named High Arsenic Content 1 (HAC1). Complementation verified the identity of HAC1, and expression in Escherichia coli lacking a functional arsenate reductase confirmed the arsenate reductase activity of HAC1. The HAC1 protein accumulates in the epidermis, the outer cell layer of the root, and also in the pericycle cells surrounding the central vascular tissue. Plants lacking HAC1 lose their ability to efflux arsenite from roots, leading to both increased transport of arsenic into the central vascular tissue and on into the shoot. HAC1 therefore functions to reduce arsenate to arsenite in the outer cell layer of the root, facilitating efflux of arsenic as arsenite back into the soil to limit both its accumulation in the root and transport to the shoot. Arsenate reduction by HAC1 in the pericycle may play a role in limiting arsenic loading into the xylem. Loss of HAC1-encoded arsenic reduction leads to a significant increase in arsenic accumulation in shoots, causing an increased sensitivity to arsenate toxicity. We also confirmed the previous observation that the ACR2 arsenate reductase in A. thaliana plays no detectable role in arsenic metabolism. Furthermore, ACR2 does not interact epistatically with HAC1, since arsenic metabolism in the acr2 hac1 double mutant is disrupted in an identical manner to that described for the hac1 single mutant. Our identification of HAC1 and its associated natural variation provides an important new resource for the development of low arsenic-containing food such as rice.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Arseniato Redutases/metabolismo , Arsênio/metabolismo , Estudo de Associação Genômica Ampla , Sequência de Aminoácidos , Proteínas de Arabidopsis/genética , Arseniato Redutases/genética , Epistasia Genética , Genes de Plantas , Loci Gênicos , Modelos Biológicos , Dados de Sequência Molecular , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Reprodutibilidade dos Testes , Análise de Sequência de Proteína
7.
World J Orthop ; 15(1): 94-100, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38293263

RESUMO

BACKGROUND: Avulsion fracture of the ischial tuberosity is a relatively clinically rare type of trauma that is mainly incurred by adolescents during competitive sports activities. According to previous literature, the most commonly involved sports are soccer, sprinting, and gymnastics, in descending order. Dance-induced avulsion fracture of the ischial tuberosity and ischial ramus is extremely clinically rare. CASE SUMMARY: A case of a neglected avulsion fracture of the ischial tuberosity and ischial ramus was diagnosed in a young female dancer who complained of pain and restricted movement of her right hip. She stated that she had suffered the injury while performing a split leap during a dance performance 9 mo prior. Eventually, she underwent surgery and obtained satisfactory treatment results. CONCLUSION: Early diagnosis of these fractures is important to ensuring early proper treatment towards a quicker recovery. For old fractures with nonunion and chronic buttock pain, surgery is a preferred therapeutic choice with good treatment outcomes.

8.
Adv Mater ; 35(40): e2305149, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37528535

RESUMO

Optimizing charge transfer and alleviating volume expansion in electrode materials are critical to maximize electrochemical performance for energy-storage systems. Herein, an atomically thin soft-rigid Co9 S8 @MoS2 core-shell heterostructure with dual cation vacancies at the atomic interface is constructed as a promising anode for high-performance sodium-ion batteries. The dual cation vacancies involving VCo and VMo in the heterostructure and the soft MoS2 shell afford ionic pathways for rapid charge transfer, as well as the rigid Co9 S8 core acting as the dominant active component and resisting structural deformation during charge-discharge. Electrochemical testing and theoretical calculations demonstrate both excellent Na+ -transfer kinetics and pseudocapacitive behavior. Consequently, the soft-rigid heterostructure delivers extraordinary sodium-storage performance (389.7 mA h g-1 after 500 cycles at 5.0 A g-1 ), superior to those of the single-phase counterparts: the assembled Na3 V2 (PO4 )3 ||d-Co9 S8 @MoS2 /S-Gr full cell achieves an energy density of 235.5 Wh kg-1 at 0.5 C. This finding opens up a unique strategy of soft-rigid heterostructure and broadens the horizons of material design in energy storage and conversion.

9.
Artigo em Inglês | MEDLINE | ID: mdl-35742276

RESUMO

Intensified urbanization has caused a linear decline in the quality of urban biodiversity and indirectly harms our current human settlement environment. Urban mountain parks provide a refuge for the animals and plants and play a vital role in satisfying residents' lives. At present, few studies are focusing on the impact of biodiversity on human mental health benefits of urban mountain parks in high-density construction areas along the coast of the Eastern Hemisphere. Here, we examined the relationship between bird abundance, Shannon diversity, Simpson diversity, and Richness and momentary mental health (positive, negative, and anxiety) in urban mountain parks. The timed species counts method was used to conduct three surveys of birds in urban mountain parks, and linear regression was performed on the relationship between bird diversity and mental health among sites. According to the regression model results, we found no significant correlation in any disturbance levels. As urban mountain parks are an essential part of the human settlement environment, how to improve the biodiversity and mental health of urban mountain parks is one of the focuses of research on biodiversity well-being in the future. Urban planning authorities and public mental health researchers should pay attention to the importance of biodiversity in urban development and consider how to realize the beautiful vision of the harmonious coexistence of humans, animals, plants, and the environment in which we live.


Assuntos
Aves , Saúde Mental , Animais , Biodiversidade , China , Cidades , Ecossistema , Parques Recreativos , Plantas
10.
Animals (Basel) ; 12(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36496963

RESUMO

Urban parks, as critical components of the urban green space, have practical significance in studying the influence of landscape characteristics on birds. Nine urban parks in Fuzhou, China, were used as study objects to explore the influence of landscape features (patch, landscape, and surrounding environment indices) on bird communities. The results showed that (1) from December 2021 to February 2022, we found a total of 2874 individuals belonging to 61 species of 9 orders, 32 families, which were dominated by the birds of Passeriformes (37 species of 24 families, accounting for 89.91% of the total number of individuals) and resident birds in Fuzhou urban parks (n = 30; 85.46%); (2) The park area, park perimeter, woodland area, grassland area, and the park shape index increased as the distance to the city center increases; (3) Bird diversity responds differently to different landscape features. The total abundance of birds, the abundance of winter migrant birds, and the richness of winter migrant birds increased with the park area. And the park shape index affects positively for the the α-diversity of birds and the abundance of resident birds. Woodland proportion and waterbody shape index affected positively on the richness and α-diversity of resident birds. To promote the diversity of regional birds, it is recommended that the construction and planning of urban parks should enlarge the park area as much as possible, increase the proportion of woodland, and make shorelines more irregular. Our study could serve as a reference for the construction of biodiversity enhancements in core green areas of urban parks.

11.
Mol Plant ; 14(4): 556-570, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33429094

RESUMO

Many important crops (e.g., tuber, root, and tree crops) are cross-pollinating. For these crops, no inbred lines are available for genetic study and breeding because they are self-incompatible, clonally propagated, or have a long generation time, making the identification of agronomically important genes difficult, particularly in crops with a complex autopolyploid genome. In this study, we developed a method, OutcrossSeq, for mapping agronomically important loci in outcrossing crops based on whole-genome low-coverage resequencing of a large genetic population, and designed three computation algorithms in OutcrossSeq for different types of outcrossing populations. We applied OutcrossSeq to a tuberous root crop (sweet potato, autopolyploid), a tree crop (walnut tree, highly heterozygous diploid), and hybrid crops (double-cross populations) to generate high-density genotype maps for the outcrossing populations, which enable precise identification of genomic loci underlying important agronomic traits. Candidate causative genes at these loci were detected based on functional clues. Taken together, our results indicate that OutcrossSeq is a robust and powerful method for identifying agronomically important genes in heterozygous species, including polyploids, in a cost-efficient way. The OutcrossSeq software and its instruction manual are available for downloading at www.xhhuanglab.cn/tool/OutcrossSeq.html.


Assuntos
Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Genoma de Planta/genética , Genótipo , Melhoramento Vegetal , Poliploidia
18.
Front Plant Sci ; 9: 270, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29545819

RESUMO

Zinc (Zn) is an essential element for plant growth and development, and Zn derived from crop plants in the diet is also important for human health. Here, we report that genetic variation in Heavy Metal-ATPase 4 (HMA4) controls natural variation in leaf Zn content. Investigation of the natural variation in leaf Zn content in a world-wide collection of 349 Arabidopsis thaliana wild collected accessions identified two accessions, Van-0 and Fab-2, which accumulate significantly lower Zn when compared with Col-0. Both quantitative trait loci (QTL) analysis and bulked segregant analysis (BSA) identified HMA4 as a strong candidate accounting for this variation in leaf Zn concentration. Genetic complementation experiments confirmed this hypothesis. Sequence analysis revealed that a 1-bp deletion in the third exon of HMA4 from Fab-2 is responsible for the lose of function of HMA4 driving the low Zn observed in Fab-2. Unlike in Fab-2 polymorphisms in the promoter region were found to be responsible for the weak function of HMA4 in Van-0. This is supported by both an expression analysis of HMA4 in Van-0 and through a series of T-DNA insertion mutants which generate truncated HMA4 promoters in the Col-0 background. In addition, we also observed that Fab-2, Van-0 and the hma4-2 null mutant in the Col-0 background show enhanced resistance to a combination of high Zn and high Cd in the growth medium, raising the possibility that variation at HMA4 may play a role in environmental adaptation.

19.
Artigo em Inglês | MEDLINE | ID: mdl-30322076

RESUMO

Atmospheric visibility (AV), one of the most concerning environmental issues, has shown a continuous decline in China's urban areas, especially in Southeastern China. Existing studies have shown that AV is affected by air pollutants and climate change, which are always caused by human activities that are linked to socioeconomic factors, such as urban size, residents' activities, industrial activities, and urban greening. However, the contribution of socioeconomic factors to AV is still not well understood, especially from a long-term perspective, which sometimes leads to ineffective policies. In this study, we used the structural equation model (SEM) in order to quantify the contribution of socioeconomic factors on AV change in Xiamen City, China, between 1987⁻2016. The results showed that the annual average AV of Xiamen between 1987⁻2016 was 12.00 km, with a change rate of -0.315 km/year. Urban size, industrial activities, and residents' activities were found to have a negative impact on AV, while the impact of urban greening on the AV was modest. Among all of the indicators, the number of resident's vehicles, total retail sales of consumer goods, and household electricity consumption were found to have the highest negative direct impact on the AV. The resident population, urban built-up area, and secondary industry gross domestic product (GDP) were the most important indirect impact factors. Based on our results, we evaluated the existing environmental regulations and policies of Xiamen City.


Assuntos
Poluição do Ar/efeitos adversos , Atmosfera/análise , Fatores Socioeconômicos , China , Cidades , Política Ambiental/legislação & jurisprudência , Regulamentação Governamental
20.
Artigo em Inglês | MEDLINE | ID: mdl-30551634

RESUMO

Air pollution has become a critical issue in the urban areas of southeastern China in recent years. A complete understanding of the tempo-spatial characteristics of air pollution can help the public and governmental bodies manage their lives and work better. In this study, data for six criteria air pollutants (including particulate matter (PM2.5, PM10), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2) and ozone (O3)) from 37 sites in nine major cities within Fujian Province, China were collected between January 2015 to December 2016, and analyzed. We analyzed the spatial and temporal variations of these six criteria pollutants, as well as the attainment rates, and identified what were the major pollutants. Our results show that: (1) the two-year mean values of PM2.5 and PM10 exceeded the Chinese National Ambient Air Quality Standard (CAAQS) standard I levels, whereas other air pollutants were below the CAAQS standard I; (2) the six criteria air pollutants show spatial variations (i.e. most air pollutants were higher in the city center areas, followed by suburban areas and exurban areas, except for O3; and the concentrations of PM10, PM2.5, NO2, O3 were higher in coastal cities than in inland cities); (3) seasonal variations and the no attainment rates of air pollutants were found to be higher in cold seasons and lower in warm seasons, except for O3; (4) the most frequently present air pollutant was PM10, with PM2.5 and O3 being the second and third most frequent, respectively; (5) all the air pollutants, except O3, showed positive correlations with each other. These results provide additional information for the effective control of air pollution in the province of Fujian.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Poluentes Atmosféricos/normas , China , Cidades , Estações do Ano
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