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Accessibility of health services signifies the quality and equitability of universal health provision. The hierarchical medical system recently implemented in China offers the policy instruments to improve medical services to the elderly in an aging society. As the critical primary care gateway, accessibility to community hospitals has significant impacts on people’s health. However, current research has paid little attention to spatial accessibility within walking distance of community hospitals, especially for the elderly. This study selected four districts with different urbanization levels in the rapidly developing Beijing metropolis. The spatial interaction model was applied to measure the accessibility of community hospitals for the elderly at the community level. An attractiveness index was computed based on key hospital traits. The results showed that: (1) community hospitals could cover 82.66% of elderly residents, and 77.63% of the communities were within walking distance. The served elderly proportion was relatively high in central urban areas and low in the suburbs. (2) The attractiveness indices of hospitals varied notably between districts, with higher values in more urbanized areas. (3) The spatial accessibility for the elderly of hospitals differed significantly between the four districts, with a descending gradient from central to suburban and rural areas, as indicated by the Gini coefficients and Lorenz curves. (4) The accessibility index was strongly related to the served elderly population and the hospital–residence distance. The findings provide policy directions to the government, including providing more primary-care resources to suburban and rural areas, building new community hospitals in identified provision gaps, upgrading some clinics to hospitals in rural areas, and planning hospitals according to the projected trend of the elderly population in terms of quantity and distribution. The considerable provision disparity between core urban, suburban and rural areas can be addressed by refined spatial health planning informed by research.

Background The transcription factor WRKYs play significant roles in plant growth, development, and defense responses. However, in cotton, the molecular mechanism of most WRKY proteins and their involvement in Verticillium wilt tolerance are not well understood. Results GhWRKY70 was greatly up-regulated in cotton by Verticillium dahliae. Subcellar localization suggested that the GhWRKY70 was only located in the nucleus. Transcriptional activation of GhWRKY70 was further demonstrated that the GhWRKY70 functioned as a transcriptional activator. The transgenic Arabidopsis with GhWRKY70 plants exhibited better growth performance, higher lignin content, antioxidant enzyme activities and Jasmonic acid (JA) levels compared to wild type after infection with V. dahliae. In addition, the transgenic Arabidopsis resulted in enhanced expression level of AtAOS1, related JA synthesis gene, further leading to an increase in higher JA accumulation compared to wild type. However, the proportion of disease index (DI) values of the VIGS-treated cotton plants with TRV:WRKY70 plants were also significantly higher than VIGS-treated with TRV:00. Chlorophyll, lignin content and JA level of TRV:WRKY70 plants were significantly lower than that of TRV:00 plants. The GhAOS1 expression and JA abundance in TRV:WRKY70 plants was decreased. The GhWRKY70 protein was confirmed to bind to the W-box element in the promoter region of GhAOS by yeast one-hybrid assay and transient expression. Conclusions These results indicate that the GhWRKY70 transcription factor was a positive regulator in Verticillium wilt tolerance of cotton, and may promote production of JA via regulation of GhAOS1 expression.

Cotton produces natural fiber for the textile industry. The genetic effects of genomic structural variations underlying agronomic traits remain unclear. Here, we generate two high-quality genomes of Gossypium hirsutum cv. NDM8 and Gossypium barbadense acc. Pima90, and identify large-scale structural variations in the two species and 1,081 G. hirsutum accessions. The density of structural variations is higher in the D-subgenome than in the A-subgenome, indicating that the D-subgenome undergoes stronger selection during species formation and variety development. Many structural variations in genes and/or regulatory regions potentially influencing agronomic traits were discovered. Of 446 significantly associated structural variations, those for fiber quality and Verticillium wilt resistance are located mainly in the D-subgenome and those for yield mainly in the A-subgenome. Our research provides insight into the role of structural variations in genotype-to-phenotype relationships and their potential utility in crop improvement., High-quality genomes of two cultivated tetraploid cottons Gossypium hirsutum cv. NDM8 and Gossypium barbadense acc. Pima90 and resequencing of 1,081 G. hirsutum accessions provide insights into the role of structural variations.

Cotton (Gossypium hirsutum) is constantly attacked by pathogens and insects. The most efficient control strategy is to develop resistant varieties using broad-spectrum gene resources. Several resistance loci harboured by superior varieties have been identified through genome-wide association studies. However, the key genes and/or loci have not been functionally identified. In this study, we identified a locus significantly associated with Verticillium wilt (VW) resistance, and within a 145.5-kb linkage disequilibrium, two non-specific lipid transfer protein genes (named GhnsLTPsA10) were highly expressed under Verticillium pathogen stress. The expression of GhnsLTPsA10 significantly increased in roots upon Verticillium dahliae stress but significantly decreased in leaves under insect attack. Furthermore, GhnsLTPsA10 played antagonistic roles in positively regulating VW and Fusarium wilt resistance and negatively mediating aphid and bollworm resistance in transgenic Arabidopsis and silenced cotton. By combining transcriptomic, histological and physiological analyses, we determined that GhnsLTPsA10-mediated phenylpropanoid metabolism further affected the balance of the downstream metabolic flux of flavonoid and lignin biosynthesis. The divergent expression of GhnsLTPsA10 in roots and leaves coordinated resistance of cotton against fungal pathogens and insects via the redirection of metabolic flux. In addition, GhnsLTPsA10 contributed to reactive oxygen species accumulation. Therefore, in this study, we elucidated the novel function of GhnsLTP and the molecular association between disease resistance and insect resistance, balanced by GhnsLTPsA10. This broadens our knowledge of the biological function of GhnsLTPsA10 in crops and provides a useful locus for genetic improvement of cotton.

Emerging microplastics (MPs) pollution and continuing acid rain (AR) co-exist in terrestrial ecosystems, and are considered as threats to ecosystems health. However, few data are available on MPs-AR interactions in plant-microbe-soil systems. Here, a microcosm experiment was manipulated to elucidate the co-exposure of polyethylene MPs (PE MPs; 1%, 5% and 10%) and AR (pH 4.0) on soil-lettuce system, in which the properties of soil and lettuce, and their links were explored. We found that 10% PE MPs increased soil CO

WRKY transcription factors are involved in complex signalling processes that occur during stress responses. However, in contrast to the exploration of such mechanisms in model plants, far less research has focussed on the WRKY family in cotton. We previously identified GbWRKY1 in cotton (Gossypium barbadense), the expression of which is induced upon infection by Verticillium dahliae. Our current results indicate that this gene with three introns, has a group of cis-acting elements in its promoter that are associated with plant growth and development as well as responses to environmental stresses. Here, we used virus-induced gene silencing to characterize the role of GbWRKY1. Silencing in cotton simultaneously up-regulated salicylic acid (SA)-mediated responses and inhibited jasmonate (JA)-inducible and ethylene (ET)-inducible defences, resulting in an increased susceptibility to V. dahliae. However, when compared with wild-type Arabidopsis, transgenic plants exhibited more resistance to infection with V. dahliae. In the latter genotype, expression was increased for pathogen-related PR4 and ACS2, two genes involved in the JA pathway and ET biosynthesis, while expression of PR5, involved in the SA pathway, decreased after V. dahliae infection. Moreover, POD activity and lignin content related to ethylene synthesis in transgenic Arabidopsis were higher than those in wild-type Arabidopsis after V. dahliae infection. Collectively, these findings suggest that GbWRKY1 is regulated by signalling pathways for SA, JA and ET, and mainly involved in resistance to V. dahliae attack by ET signalling pathway the response. This highlights the importance of WRKYs in regulating pathogen-induced responses and plant development.

Background Verticillium wilt is a widespread and destructive disease, which causes serious loss of cotton yield and quality. Long non-coding RNA (lncRNA) is involved in many biological processes, such as plant disease resistance response, through a variety of regulatory mechanisms, but their possible roles in cotton against Verticillium dahliae infection remain largely unclear. Results Here, we measured the transcriptome of resistant G. hirsutum following infection by V. dahliae and 4277 differentially expressed lncRNAs (delncRNAs) were identified. Localization and abundance analysis revealed that delncRNAs were biased distribution on chromosomes. We explored the dynamic characteristics of disease resistance related lncRNAs in chromosome distribution, induced expression profiles, biological function, and these lncRNAs were divided into three categories according to their induced expression profiles. For the delncRNAs, 687 cis-acting pairs and 14,600 trans-acting pairs of lncRNA-mRNA were identified, which indicated that trans-acting was the main way of Verticillium wilt resistance-associated lncRNAs regulating target mRNAs in cotton. Analyzing the regulation pattern of delncRNAs revealed that cis-acting and trans-acting lncRNAs had different ways to influence target genes. Gene Ontology (GO) enrichment analysis revealed that the regulatory function of delncRNAs participated significantly in stimulus response process, kinase activity and plasma membrane components. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that delncRNAs participated in some important disease resistance pathways, such as plant-pathogen interaction, alpha-linolenic acid metabolism and plant hormone signal transduction. Additionally, 21 delncRNAs and 10 target genes were identified as being involved in alpha-linolenic acid metabolism associated with the biosynthesis of jasmonic acid (JA). Subsequently, we found that GhlncLOX3 might regulate resistance to V. dahliae through modulating the expression of GhLOX3 implicated in JA biosynthesis. Further functional analysis showed that GhlncLOX3-silenced seedlings displayed a reduced resistance to V. dahliae, with down-regulated expression of GhLOX3 and decreased content of JA. Conclusion This study shows the dynamic characteristics of delncRNAs in multiaspect, and suggests that GhlncLOX3-GhLOX3-JA network participates in response to V. dahliae invasion. Our results provide novel insights for genetic improvement of Verticillium wilt resistance in cotton using lncRNAs.

Plant receptor-like kinases (RLKs) are important players in response to pathogen infections. Verticillium and Fusarium wilts, caused by Verticillium dahliae (Vd) and Fusarium oxysporum f. sp vasinfectum (Fov), respectively, are among the most devastating diseases in cotton (Gossypium spp). To understand the cotton response to these soil-borne fungal pathogens, we performed a genome-wide in silico characterization and functional screen of diverse RLKs for their involvement in cotton wilt diseases. We identified Gossypium hirsutum GhWAK7A, a wall-associated kinase, that positively regulates cotton response to both Vd and Fov infections. Chitin, the major constituent of the fungal cell wall, is perceived by lysin-motif-containing RLKs (LYKs/CERK1), leading to the activation of plant defense against fungal pathogens. A conserved chitin sensing and signaling system is present in cotton, including chitin-induced GhLYK5-GhCERK1 dimerization and phosphorylation, and contributes to cotton defense against Vd and Fov. Importantly, GhWAK7A directly interacts with both GhLYK5 and GhCERK1 and promotes chitin-induced GhLYK5-GhCERK1 dimerization. GhWAK7A phosphorylates GhLYK5, which itself does not have kinase activity, but requires phosphorylation for its function. Consequently, GhWAK7A plays a crucial role in chitin-induced responses. Thus, our data reveal GhWAK7A as an important component in cotton response to fungal wilt pathogens by complexing with the chitin receptors.

Verticillium dahliae is a phytopathogenic fungal pathogen that causes vascular wilt diseases responsible for considerable decreases in cotton yields. The lignification of cell wall appositions is a conserved basal defence mechanism in the plant innate immune response. However, the function of laccase in defence-induced lignification has not been described. Screening of an SSH library of a resistant cotton cultivar, Jimian20, inoculated with V. dahliae revealed a laccase gene that was strongly induced by the pathogen. This gene was phylogenetically related to AtLAC15 and contained domains conserved by laccases; therefore, we named it GhLAC15. Quantitative reverse transcription-polymerase chain reaction indicated that GhLAC15 maintained higher expression levels in tolerant than in susceptible cultivars. Overexpression of GhLAC15 enhanced cell wall lignification, resulting in increased total lignin, G monolignol and G/S ratio, which significantly improved the Verticillium wilt resistance of transgenic Arabidopsis. In addition, the levels of arabinose and xylose were higher in transgenic plants than in wild-type plants, which resulted in transgenic Arabidopsis plants being less easily hydrolysed. Furthermore, suppression of the transcriptional level of GhLAC15 resulted in an increase in susceptibility in cotton. The content of monolignol and the G/S ratio were lower in silenced cotton plants, which led to resistant cotton cv. Jimian20 becoming susceptible. These results demonstrate that GhLAC15 enhances Verticillium wilt resistance via an increase in defence-induced lignification and arabinose and xylose accumulation in the cell wall of Gossypium hirsutum. This study broadens our knowledge of defence-induced lignification and cell wall modifications as defence mechanisms against V. dahliae.

Phosphorescence is among the many functional features of the excited organic molecules. Organic molecules with long-lived triplet excited states enable exciton migration over long distance, which is essential in a variety of optoelectronic applications such as photovoltaics, photocatalytic reactions, display and lighting system, molecular sensing and biological imaging. In general, phosphorescence materials involve the organometallic compounds that are expensive, such as Pt, Ir and so on. Owing to the presence of metal, the phosphorescence materials is toxic and are also intrinsically unstable in the case of high-energy blue emitters. Therefore the purely organic materials that show room-temperature phosphorescence (RTP) are attractive alternatives to organometallic phosphors. The triplet excitons are not commonly generated in organic materials and are mostly consumed through radiationless processes, such as vibrational dissipation and oxygen-mediated quenching, under ambient conditions. Recently, a variety of methods from molecular design to material design to access organic room temperature phosphorescence have been explored. This review focus on the recent advancements in the field of organic phosphorescence, classifying the strategies based on material design. The outlook of organic room temperature phosphorescence is also discussed. The basic concepts for RTP process are introduced to demonstrate what’s the key factors to obtain efficient RTP. They are: (1) the promotion of both singlet-to-triplet and triplet-to-singlet intersystem crossing, and (2) suppression of the nonradiative quenching processes from the triplet to the ground state. Comparisons between RTP and delayed fluorescence are also made in the review. The triplet excited states of organic molecules can be stabilized by interactions of host molecules and guest molecules, rigid solid-crystallized structures and the chromophore embedded in polymer, which can suppress the nonradiative deactivation pathways and rates of triplet excitons by restricting the vibrational dissipation of long-lived triplets, and considerably increase the possibility of radiative decay. The directed intermolecular halogen bonding can also promote the intersystem-crossing processes by enhancing spin-orbit coupling, and improve the radiative decay. In most studies, various methods are combined to obtain phosphorescence materials of long-lived triplet excited states with high quantum yield.

Face-to-face interfacial assembly of TiO

The function of a member of the actin-depolymerizing factor family from Gossypium barbadense, GbADF1, was investigated. Tobacco (Nicotiana tabacum) lines expressing GbADF1 were produced by Agrobacterium-mediated transformation. Southern and northern blot analyses showed that GbADF1 was successfully incorporated as a single copy into the tobacco genome and stably expressed in three lines of T1 transgenic tobacco plants. Biological changes were detected in these transgenic lines, wherein GbADF1 transgenic seedlings exhibited shorter hypocotyls along with fewer root hairs than those of control plants. Moreover, guard cells of leaves of the transgenic plants were induced to close stomata, while flowering was delayed 5 days in T1 lines compared to those of empty vector transgenic control plants. Segregation of GbADF1 in the T2 generation fits the expected 3:1 ratio corresponding to a single dominant gene. Subsequently, GbADF1 was fused to the green fluorescent protein gene to generate a fusion expression vector. Transient expression analysis indicated that this fusion protein was localized in the nucleus and cytoskeleton of epidermal cells of onion. These results suggest that actin-depolymerizing factor 1 gene from G. barbadense plays an important role in the process of plant cell morphogenesis.

UDP-glucuronate decarboxylase (UDP-xylose synthase; UXS, EC 4.1.1.35) is an essential enzyme of the non-cellulosic polysaccharide biosynthetic pathway. In the present study, using transient expression of fluorescently labeled Gossypium hirsutum UXS (GhUXS3) protein in onion epidermal cells, we observed that this protein was distributed in the cytoplasm. The GhUXS3 cDNA of cotton was expressed in an antisense orientation in Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation. Homozygous plants showing down-regulation of UXS were analyzed with northern blots. Compared to the untransformed control, transgenic plant showed shorter roots, earlier blossom formation, and delayed senescence. Biochemical analysis indicated that levels of rhamnose, mannose, galactose, glucose, xylose, and cellulose were reduced in some of the down-regulated antisense plants. These results suggest that GhUXS3 regulates the conversion of non-cellulosic polysaccharides and modulates their composition in plant cell walls. We also discuss a possible cellular function for GhUXS in determining the quality of cotton fibers.

Hydrogen evolution was observed from the noble-metal-free catalyst systems, comprising Rose Bengal, BFx-bridged cobaloximes, and triethylamine, in an aqueous solution under irradiation of visible light. Two types of BFx-bridged cobaloximes—namely, the annulated cobaloximes [Co(dmgBF2)2(H2O)2] (1, dmgBF2 = (difluoroboryl)dimethylglyoximate anion) and [Co(dpgBF2)2(H2O)2] (2, dpgBF2 = (difluoroboryl)diphenylglyoximate anion), and the clathrochelated cobaloximes [Co(dmg(BF)2/3)3](BF4) (3) and [Co(dpg(BF)2/3)3](BF4) (4)—were used as catalysts. Among the four cobalt complexes, complex 1 displayed the highest hydrogen-evolving efficiency, with turnovers up to 327. Complexes 2 and 4 that bear the diphenylglyoximate ligands exhibited much lower efficiencies as compared with their analogues 1 and 3 that have the dimethylglyoximate ligands. The hydrogen-evolving efficiency of the annulated cobalt(II) complex 1 that contains two labile axial ligands is more than three times as high as that of the encapsulated cobalt(...

To analyze the complex sympathetic inrush characteristics of HVDC and study the methods of suppression, making up the blank of Electromagnetic transient simulation software of PSCAD/EMTDC not considering the hysteresis characteristics of ferromagnetic material of transformer cores as well, a new three-phase transformer model with hysteresis characteristic for electromagnetic transients based on the PSCAD/EMTDC is presented, which derives from the ideas of the transformer model considering hysteresis characteristics in ATP-EMTP, it consists of Type96 and BCTRAN. This model adds magnetizing branch considering hysteresis characteristics based on UMEC model. It's full use of the advantages of UMEC model, without using winding turns, the core cross-sectional area, the core length, etc, and the hysteresis characteristics of transformer can be described when using experimental data obtained. The simulation results show that the model both have high simulation accuracy, and because the parameters readily available, it's easy for user to use in PSCAD/EMTDC and to promote the use of the transformer model in engineering application when considering transformers with hysteresis characteristics.

Commutation failure caused by AC system failure is most common phenomenon of AC/DC dynamic interaction. The research about the DC commutation failure simply caused by AC system failure at a certain moment may not accurately reflect the complexity of HVDC commutation failure. This paper points out that the commutation voltage amplitude and phase angle and the closing time of fault are the main factors of commutation failure time discreteness in the HVDC transmission system, from the perspective of the physical nature of valve commutation process and the commutation voltage time area. Then, theoretically analyzed the features of the three-phase fault and single phase fault occur on AC bus, the paper concludes the change regularity of line voltage amplitude and line voltage phase which after Y-Y and Y-D1 transformer along with the change of transition resistance. Finally, Using PSCAD/EMTDC, the typical bipolar 12 Pulses DC system model with detailed control system is set up. The regularity of critical transition resistance in different fault moment of two fault types is analyzed to conclude the influence factors and regularity of commutation failure time discreteness in the HVDC transmission system. The results show that the most unfavorable condition to the commutation is when the AC system fault time corresponds to the pulse triggering time of commutation valve.

Expression of DHS1 in cotton is induced upon infection by Verticillium dahliae , and overexpression of GhDHS1 endows transgenic Arabidopsis plants excellent Verticillium resistance. Verticillium wilt is caused by a soil-borne fungus Verticillium dahliae. Resistance in most cotton cultivars is either scarce or unavailable, making Verticillium wilt a major obstacle in cotton production. Here, we identified a 3-deoxy-7-phosphoheptulonate synthase (DHS, EC 4.1.2.15) gene from Gossypium hirsutum, named GhDHS1. Its 1620 bp open reading frame encodes a putative 59.4 kDa protein. Phylogenetic analysis indicated that GhDHS1 is clustered in a clade with potato and tomato DHSs that can be induced by wounding and elicitors, respectively. Expression analysis demonstrated that GhDHS1 is constitutively expressed in cotton roots and stems, but transcripts are rare or non-existent in the leaves. Subcellular localization showed that GhDHS1 occurs in the plastids. When plants of three cultivars were inoculated with V. dahliae, DHS1 expression was more significantly up-regulated in the roots of resistant G. barbadense cv. Pima90-53 and G. hirsutum cv. Jimian20 than in the susceptible G. hirsutum cv. Han208. This suggested that DHS1 is involved in the cotton resistance to Verticillium wilt. Furthermore, GhDHS1 overexpressing transgenic lines of Arabidopsis were developed via Agrobacterium tumefaciens-mediated transformation. Compared with the untransformed WT (wild type), these transgenic plants showed excellent Verticillium wilt resistance with a significantly lower disease index. The overexpressing transgenic lines also had significantly longer primary roots and greatly increased xylem areas under V. dahliae infection. Overall, our results indicate that GhDHS1 performs a role in the cotton resistance to V. dahliae and would be potential to breeding cottons of Verticillium wilt resistance.

Plant phosphoinositide-specific phospholipases C (PI-PLCs) function in several essential plant processes associated with either development or environmental stress. In this report, we examined the expression patterns of TaPLC1 under drought and high salinity stress at the transcriptional and post-transcriptional levels. TaPLC1 mRNA was expressed in all wheat organs examined. U73122 and edelfosine, the PLC inhibitor, impaired seedling growth and enhanced seedling sensitivity to drought and high salinity stress. Though TaPLC1 expression in wheat was lowest at the seedling stage, it was strongly induced under conditions of stress. When 6-day-old wheat seedlings were treated with 200 mM NaCl or 20% (w/v) PEG 6000 for 6 or 12 h, respectively, the TaPLC1 transcript level increased by 16-fold compared to the control. Western blotting showed that the TaPLC protein concentration was also maintained at a high level from 24 to 48 h during stress treatment. Together, our results indicate the possible biological functions of TaPLC1 in regulating seedling growth and the response to drought and salinity stress.

Overexpression of a cotton defense-related gene GbSTK in Arabidopsis resulted in enhancing pathogen infection and oxidative stress by activating multiple defense-signaling pathways. Serine/threonine protein kinase (STK) plays an important role in the plant stress-signaling transduction pathway via phosphorylation. Most studies about STK genes have been conducted with model species. However, their molecular and biochemical characterizations have not been thoroughly investigated in cotton. Here, we focused on one such member, GbSTK. RT-PCR indicated that it is induced not only by Verticillium dahliae Kleb., but also by signaling molecules. Subcellular localization showed that GbSTK is present in the cell membrane, cytoplasm, and nucleus. Overexpression of GbSTK in Arabidopsis resulted into the enhanced resistance to V. dahliae. Moreover, Overexpression of GbSTK elevated the expression of PR4, PR5, and EREBP, conferring on transgenic plants enhanced reactive oxygen species scavenging capacity and oxidative stress tolerance. Our results suggest that GbSTK is active in multiple defense-signaling pathways, including those involved in responses to pathogen infection and oxidative stress.