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1.
Waste Manag Res ; : 734242X231192766, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37641494

RESUMO

Prediction of municipal solid waste (MSW) generation plays an essential role in effective waste management. The main objectives of this study were to develop models for accurate prediction of MSW generation (MSWG) and analyze the influence of dominant variables on MSWG. To elevate the model's prediction accuracy, more than 50 municipal variables were considered original variables, which were selected from 12 categories. According to the screening results, the dominant variables are classified into four categories: urban greening, population size and residential density, regional economic development and resident income and expenditure. Among the seven machine learning methods, back propagation (BP) neural network has the best model evaluation effect. The R2 of the BP neural network model of Jiangsu, Zhejiang and Shandong provinces were 0.969, 0.941 and 0.971 respectively. The prediction accuracy of Shandong province (93.8%) was the best, followed by Jiangsu province (92.3%) and Zhejiang province (72.7%). The correlation between dominant variables and the MSWG was mined, suggesting that regional GDP and the total retail sales of consumer goods were the most important dominant variables affecting MSWG. Moreover, the MSWG might not absolutely associate with the population size and residential density. The method used in this study is a practical tool for policymakers on regional/local waste management and MSWG control.

2.
Plant Cell ; 31(3): 563-578, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30760562

RESUMO

Pseudogenes (Ψs), nonfunctional relatives of functional genes, form by duplication or retrotransposition, and loss of gene function by disabling mutations. Evolutionary analysis provides clues to Ψ origins and effects on gene regulation. However, few systematic studies of plant Ψs have been conducted, hampering comparative analyses. Here, we examined the origin, evolution, and expression patterns of Ψs and their relationships with noncoding sequences in seven angiosperm plants. We identified ∼250,000 Ψs, most of which are more lineage specific than protein-coding genes. The distribution of Ψs on the chromosome indicates that genome recombination may contribute to Ψ elimination. Most Ψs evolve rapidly in terms of sequence and expression levels, showing tissue- or stage-specific expression patterns. We found that a surprisingly large fraction of nontransposable element regulatory noncoding RNAs (microRNAs and long noncoding RNAs) originate from transcription of Ψ proximal upstream regions. We also found that transcription factor binding sites preferentially occur in putative Ψ proximal upstream regions compared with random intergenic regions, suggesting that Ψs have conditioned genome evolution by providing transcription factor binding sites that serve as promoters and enhancers. We therefore propose that rapid rewiring of Ψ transcriptional regulatory regions is a major mechanism driving the origin of novel regulatory modules.


Assuntos
Evolução Molecular , Genoma de Planta/genética , Magnoliopsida/genética , Pseudogenes/genética , Elementos Reguladores de Transcrição/genética , Sítios de Ligação , DNA Intergênico/genética , Genômica , Mutação , RNA Longo não Codificante/genética , RNA não Traduzido/genética , Recombinação Genética
3.
BMC Infect Dis ; 22(1): 880, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36424534

RESUMO

The Omicron transmission has infected nearly 600,000 people in Shanghai from March 26 to May 31, 2022. Combined with different control measures taken by the government in different periods, a dynamic model was constructed to investigate the impact of medical resources, shelter hospitals and aerosol transmission generated by clustered nucleic acid testing on the spread of Omicron. The parameters of the model were estimated by least square method and MCMC method, and the accuracy of the model was verified by the cumulative number of asymptomatic infected persons and confirmed cases in Shanghai from March 26 to May 31, 2022. The result of numerical simulation demonstrated that the aerosol transmission figured prominently in the transmission of Omicron in Shanghai from March 28 to April 30. Without aerosol transmission, the number of asymptomatic subjects and symptomatic cases would be reduced to 130,000 and 11,730 by May 31, respectively. Without the expansion of shelter hospitals in the second phase, the final size of asymptomatic subjects and symptomatic cases might reach 23.2 million and 4.88 million by May 31, respectively. Our results also revealed that expanded vaccination played a vital role in controlling the spread of Omicron. However, even if the vaccination rate were 100%, the transmission of Omicron should not be completely blocked. Therefore, other control measures should be taken to curb the spread of Omicron, such as widespread antiviral therapies, enhanced testing and strict tracking quarantine measures. This perspective could be utilized as a reference for the transmission and prevention of Omicron in other large cities with a population of 10 million like Shanghai.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , China/epidemiologia , Quarentena , Aerossóis e Gotículas Respiratórios
4.
Biophys J ; 118(4): 898-908, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-31699333

RESUMO

Defective nitrate signaling in plants causes disorder in nitrogen metabolism, and it negatively affects nitrate transport systems, which toggle between high- and low-affinity modes in variable soil nitrate conditions. Recent discovery of a plasma membrane nitrate transceptor protein NRT1.1-a transporter cum sensor-provides a clue on this toggling mechanism. However, the general mechanistic description still remains poorly understood. Here, we illustrate adaptive responses and regulation of NRT1.1-mediated nitrate signaling in a wide range of extracellular nitrate concentrations. The results show that the homodimeric structure of NRT1.1 and its dimeric switch play an important role in eliciting specific cytosolic calcium waves sensed by the calcineurin-B-like calcium sensor CBL9, which activates the kinase CIPK23, in low nitrate concentration that is, however, impeded in high nitrate concentration. Nitrate binding at the high-affinity unit initiates NRT1.1 dimer decoupling and priming of the Thr101 site for phosphorylation by CIPK23. This phosphorylation stabilizes the NRT1.1 monomeric state, acting as a high-affinity nitrate transceptor. However, nitrate binding in both monomers, retaining the unmodified NRT1.1 state through dimerization, attenuates CIPK23 activity and thereby maintains the low-affinity mode of nitrate signaling and transport. This phosphorylation-led modulation of NRT1.1 activity shows bistable behavior controlled by an incoherent feedforward loop, which integrates nitrate-induced positive and negative regulatory effects on CIPK23. These results, therefore, advance our molecular understanding of adaptation in fluctuating nutrient availability and are a way forward for improving plant nitrogen use efficiency.


Assuntos
Arabidopsis , Nitratos , Proteínas de Transporte de Ânions , Arabidopsis/metabolismo , Transportadores de Nitrato , Nitratos/metabolismo , Proteínas de Plantas/metabolismo
5.
Entropy (Basel) ; 22(9)2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-33286794

RESUMO

As humanity struggles to find a path to resilience amidst global change vagaries, understanding organizing principles of living systems as the pillar for human existence is rapidly growing in importance. However, finding quantitative definitions for order, complexity, information and functionality of living systems remains a challenge. Here, we review and develop insights into this problem from the concept of the biotic regulation of the environment developed by Victor Gorshkov (1935-2019). Life's extraordinary persistence-despite being a strongly non-equilibrium process-requires a quantum-classical duality: the program of life is written in molecules and thus can be copied without information loss, while life's interaction with its non-equilibrium environment is performed by macroscopic classical objects (living individuals) that age. Life's key energetic parameter, the volume-specific rate of energy consumption, is maintained within universal limits by most life forms. Contrary to previous suggestions, it cannot serve as a proxy for "evolutionary progress". In contrast, ecosystem-level surface-specific energy consumption declines with growing animal body size in stable ecosystems. High consumption by big animals is associated with instability. We suggest that the evolutionary increase in body size may represent a spontaneous loss of information about environmental regulation, a manifestation of life's algorithm ageing as a whole.

6.
Planta ; 249(3): 635-646, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30327883

RESUMO

MAIN CONCLUSION: Cell-size enlargement plays a pivotal role in increasing the leaf size of triploid poplar, and polyploidization could change leaf shape. ABP1 was highly expressed in triploid plants and positively related to cell size. In the plant kingdom, the leaf is the most important energy production organ, and polyploidy often exhibits a "Gigas" effect on leaf size, which benefits agriculture and forestry. However, little is known regarding the cellular and molecular mechanisms underlying the leaf size superiority of polyploid woody plants. In the present study, the leaf area and abaxial epidermal cells of diploid and triploid full-sib groups and their parents were measured at three different positions. We measured the expression of several genes related to cell division and cell expansion. The results showed that the leaf area of triploids was significantly larger than that of diploids, and the triploid group showed transgressive variation compared to their full-sib diploid group. Cell size but not cell number was the main reason for leaf size variation. Cell expansion was in accordance with leaf enlargement. In addition, the leaf shape changes in triploids primarily resulted from a significant decrease in the leaf ratio of length to -width. Auxin-binding protein 1 (ABP1) was highly expressed in triploids and positively related to leaf size. These results enhanced the current understanding that giant leaf is affected by polyploidy vigor. However, significant heterosis is not exhibited in diploid offspring. Overall, polyploid breeding is an effective strategy to enhance leaf size, and Populus, as an ideal material, plays an important role in studying the leaf morphological variations of polyploid woody plants.


Assuntos
Diploide , Folhas de Planta/anatomia & histologia , Ploidias , Populus/genética , Triploidia , Tamanho Celular , Regulação da Expressão Gênica de Plantas/genética , Melhoramento Vegetal , Folhas de Planta/citologia , Folhas de Planta/genética , Populus/anatomia & histologia , Populus/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
7.
Plant Biotechnol J ; 17(3): 608-624, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30133117

RESUMO

In perennial woody plants, the coordinated increase of stem height and diameter during juvenile growth improves competitiveness (i.e. access to light); however, the factors underlying variation in stem growth remain unknown in trees. Here, we used linkage-linkage disequilibrium (linkage-LD) mapping to decipher the genetic architecture underlying three growth traits during juvenile stem growth. We used two Populus populations: a linkage mapping population comprising a full-sib family of 1,200 progeny and an association mapping panel comprising 435 unrelated individuals from nearly the entire natural range of Populus tomentosa. We mapped 311 quantitative trait loci (QTL) for three growth traits at 12 timepoints to 42 regions in 17 linkage groups. Of these, 28 regions encompassing 233 QTL were annotated as 27 segmental homology regions (SHRs). Using SNPs identified by whole-genome re-sequencing of the 435-member association mapping panel, we identified significant SNPs (P ≤ 9.4 × 10-7 ) within 27 SHRs that affect stem growth at nine timepoints with diverse additive and dominance patterns, and these SNPs exhibited complex allelic epistasis over the juvenile growth period. Nineteen genes linked to potential causative alleles that have time-specific or pleiotropic effects, and mostly overlapped with significant signatures of selection within SHRs between climatic regions represented by the association mapping panel. Five genes with potential time-specific effects showed species-specific temporal expression profiles during the juvenile stages of stem growth in five representative Populus species. Our observations revealed the importance of considering temporal genetic basis of complex traits, which will facilitate the molecular design of tree ideotypes.


Assuntos
Pleiotropia Genética/genética , Caules de Planta/genética , Populus/crescimento & desenvolvimento , Locos de Características Quantitativas/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Ligação Genética/genética , Populus/genética , Fatores de Tempo , Árvores/genética , Árvores/crescimento & desenvolvimento
8.
Mol Genet Genomics ; 291(3): 1069-82, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26732268

RESUMO

MicroRNAs (miRNAs) play important roles in the regulation of gene expression in various biological processes. However, the interactions between miRNAs and their targets are largely unknown in plants. As a powerful tool for identification of variation associated with traits, association genetics provides another strategy for exploration of interactions between miRNAs and their targets. Here, we conducted expression analysis and association mapping to evaluate the interaction between Pto-miR160a and its target Pto-ARF16 in Populus tomentosa. By examining the expression patterns of Pto-MIR160a and Pto-ARF16, we identified a significant, negative correlation between their expression levels, indicating that Pto-miR160a may affect the expression of Pto-ARF16. Among the single nucleotide polymorphisms (SNPs) identified in this study, one common SNP in the pre-miRNA region of Pto-miR160a altered its predicted secondary structure while another common SNP in the predicted miRNA target site changed the binding affinity of Pto-miR160a. Linkage disequilibrium (LD) analysis revealed low LD levels of Pto-MIR160a and Pto-ARF16, indicating that they are suitable for candidate gene-based association analysis. Single SNP-based association analysis identified 19 SNPs (false discovery rate Q < 0.05) in Pto-MIR160a and Pto-ARF16 associated with three phenotypic traits. Epistasis analysis further identified 36 SNP-SNP interactions between SNPs in Pto-MIR160a and SNPs in Pto-ARF16, reflecting the possible genetic interaction of Pto-miR160a and Pto-ARF16. Taking these results together, our study identified SNPs in Pto-MIR160a and Pto-ARF16 associated with tree growth and wood properties, providing SNPs with potential applications in marker-assisted breeding and evidence for the genetic interaction of Pto-miR160a and Pto-ARF16.


Assuntos
Estudos de Associação Genética/métodos , MicroRNAs/genética , Populus/genética , Fatores de Transcrição/genética , Sítios de Ligação , Epistasia Genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Desequilíbrio de Ligação , MicroRNAs/química , MicroRNAs/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , RNA de Plantas/química , RNA de Plantas/genética , RNA de Plantas/metabolismo , Fatores de Transcrição/metabolismo
9.
New Phytol ; 212(1): 150-60, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27265357

RESUMO

Variation in regulatory factors, including microRNAs (miRNAs), contributes to variation in quantitative and complex traits. However, in plants, variants in miRNAs and their target genes that contribute to natural phenotypic variation, and the underlying regulatory networks, remain poorly characterized. We investigated the associations and interactions of single-nucleotide polymorphisms (SNPs) in miRNAs and their target genes with phenotypes in 435 individuals from a natural population of Populus. We used RNA-seq to identify 217 miRNAs differentially expressed in a tension wood system, and identified 1196 candidate target genes; degradome sequencing confirmed 60 of the target sites. In addition, 72 miRNA-target pairs showed significant co-expression. Gene ontology (GO) term analysis showed that most of the genes in the co-regulated pairs participate in biological regulation. Genome resequencing found 5383 common SNPs (frequency ≥ 0.05) in 139 miRNAs and 31 037 SNPs in 819 target genes. Single-SNP association analyses identified 232 significant associations between wood traits (P ≤ 0.05) and SNPs in 102 miRNAs and 1387 associations with 478 target genes. Among these, 102 miRNA-target pairs associated with the same traits. Multi-SNP associations found 102 epistatic pairs associated with traits. Furthermore, a reconstructed regulatory network contained 12 significantly co-expressed pairs, including eight miRNAs and nine targets associated with traits. Lastly, both expression and genetic association showed that miR156i, miR156j, miR396a and miR6445b were involved in the formation of tension wood. This study shows that variants in miRNAs and target genes contribute to natural phenotypic variation and annotated roles and interactions of miRNAs and their target genes by genetic association analysis.


Assuntos
Variação Genética , MicroRNAs/genética , Populus/genética , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Genes de Plantas , Estudos de Associação Genética , Genoma de Planta , MicroRNAs/metabolismo , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Estabilidade de RNA/genética , RNA de Plantas/genética , RNA de Plantas/metabolismo , Madeira/genética , Xilema/genética , Xilema/crescimento & desenvolvimento
10.
New Phytol ; 209(3): 1067-82, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26499329

RESUMO

Deciphering the genetic architecture underlying polygenic traits in perennial species can inform molecular marker-assisted breeding. Recent advances in high-throughput sequencing have enabled strategies that integrate linkage-linkage disequilibrium (LD) mapping in Populus. We used an integrated method of quantitative trait locus (QTL) dissection with a high-resolution linkage map and multi-gene association mapping to decipher the nature of genetic architecture (additive, dominant, and epistatic effects) of potential QTLs for growth traits in a Populus linkage population (1200 progeny) and a natural population (435 individuals). Seventeen QTLs for tree height, diameter at breast height, and stem volume mapped to 11 linkage groups (logarithm of odds (LOD) ≥ 2.5), and explained 2.7-18.5% of the phenotypic variance. After comparative mapping and transcriptome analysis, 187 expressed genes (10 046 common single nucleotide polymorphisms (SNPs)) were selected from the segmental homology regions (SHRs) of 13 QTLs. Using multi-gene association models, we observed 202 significant SNPs in 63 promising genes from 10 QTLs (P ≤ 0.0001; FDR ≤ 0.10) that exhibited reproducible associations with additive/dominant effects, and further determined 11 top-ranked genes tightly linked to the QTLs. Epistasis analysis uncovered a uniquely interconnected gene-gene network for each trait. This study opens up opportunities to uncover the causal networks of interacting genes in plants using an integrated linkage-LD mapping approach.


Assuntos
Estudo de Associação Genômica Ampla , Populus/crescimento & desenvolvimento , Populus/genética , Locos de Características Quantitativas/genética , Característica Quantitativa Herdável , Biomassa , Mapeamento Cromossômico , Epistasia Genética , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Genes de Plantas , Estudos de Associação Genética , Ligação Genética , Desequilíbrio de Ligação/genética , Modelos Genéticos , Anotação de Sequência Molecular , Caules de Planta/genética , Caules de Planta/crescimento & desenvolvimento , Polimorfismo de Nucleotídeo Único/genética , Especificidade da Espécie
11.
J Exp Bot ; 67(11): 3325-38, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27091876

RESUMO

Gibberellins (GAs) regulate a wide range of important processes in plant growth and development, including photosynthesis. However, the mechanism by which GAs regulate photosynthesis remains to be understood. Here, we used multi-gene association to investigate the effect of genes in the GA-responsive pathway, as constructed by RNA sequencing, on photosynthesis, growth, and wood property traits, in a population of 435 Populus tomentosa By analyzing changes in the transcriptome following GA treatment, we identified many key photosynthetic genes, in agreement with the observed increase in measurements of photosynthesis. Regulatory motif enrichment analysis revealed that 37 differentially expressed genes related to photosynthesis shared two essential GA-related cis-regulatory elements, the GA response element and the pyrimidine box. Thus, we constructed a GA-responsive pathway consisting of 47 genes involved in regulating photosynthesis, including GID1, RGA, GID2, MYBGa, and 37 photosynthetic differentially expressed genes. Single nucleotide polymorphism (SNP)-based association analysis showed that 142 SNPs, representing 40 candidate genes in this pathway, were significantly associated with photosynthesis, growth, and wood property traits. Epistasis analysis uncovered interactions between 310 SNP-SNP pairs from 37 genes in this pathway, revealing possible genetic interactions. Moreover, a structural gene-gene matrix based on a time-course of transcript abundances provided a better understanding of the multi-gene pathway affecting photosynthesis. The results imply a functional role for these genes in mediating photosynthesis, growth, and wood properties, demonstrating the potential of combining transcriptome-based regulatory pathway construction and genetic association approaches to detect the complex genetic networks underlying quantitative traits.


Assuntos
Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Fotossíntese/genética , Polimorfismo de Nucleotídeo Único , Populus/genética , Perfilação da Expressão Gênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/crescimento & desenvolvimento , Populus/metabolismo
12.
J Exp Bot ; 67(8): 2467-82, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26912799

RESUMO

Long non-coding RNAs (lncRNAs) participate in a wide range of biological processes, but lncRNAs in plants remain largely unknown; in particular, we lack a systematic identification of plant lncRNAs involved in hormone responses. Moreover, allelic variation in lncRNAs remains poorly characterized at a large scale. Here, we conducted high-throughput RNA-sequencing of leaves from control and gibberellin (GA)-treated Populus tomentosa and identified 7655 reliably expressed lncRNAs. Among the 7655 lncRNAs, the levels of 410 lncRNAs changed in response to GA. Seven GA-responsive lncRNAs were predicted to be putative targets of 18 miRNAs, and one GA-responsive lncRNA (TCONS_00264314) was predicted to be a target mimic of ptc-miR6459b. Computational analysis predicted 939 potential cis-regulated target genes and 965 potential trans-regulated target genes for GA-responsive lncRNAs. Functional annotation of these potential target genes showed that they participate in many different biological processes, including auxin signal transduction and synthesis of cellulose and pectin, indicating that GA-responsive lncRNAs may influence growth and wood properties. Finally, single nucleotide polymorphism (SNP)-based association analysis showed that 112 SNPs from 52 GA-responsive lncRNAs and 1014 SNPs from 296 potential target genes were significantly associated with growth and wood properties. Epistasis analysis also provided evidence for interactions between lncRNAs and their potential target genes. Our study provides a comprehensive view of P. tomentosa lncRNAs and offers insights into the potential functions and regulatory interactions of GA-responsive lncRNAs, thus forming the foundation for future functional analysis of GA-responsive lncRNAs in P. tomentosa.


Assuntos
Giberelinas/farmacologia , Populus/genética , RNA Longo não Codificante/genética , Alelos , Sequência de Bases , Epistasia Genética/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genética Populacional , Genoma de Planta , MicroRNAs/genética , MicroRNAs/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Desenvolvimento Vegetal/genética , Polimorfismo de Nucleotídeo Único/genética , Populus/efeitos dos fármacos , Populus/fisiologia , RNA Longo não Codificante/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Madeira/efeitos dos fármacos , Madeira/crescimento & desenvolvimento , Madeira/fisiologia
13.
BMC Genet ; 15 Suppl 1: S3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25079290

RESUMO

BACKGROUND: To optimize marker-assisted selection programs, knowledge of the genetic architecture of phenotypic traits is very important for breeders. Generally, most phenotypes, e.g. morphological and physiological traits, are quantitatively inherited, and thus detection of the genes underlying variation for these traits is difficult. Association mapping based on linkage disequilibrium has recently become a powerful approach to map genes or quantitative trait loci (QTL) in plants. RESULTS: In this study, association analysis using 20 simple sequence repeat (SSR) markers was performed to detect the marker loci linked to 13 morphological traits and 10 physiological traits in a wild P. simonii population that consisted of 528 individuals sampled from 16 sites along the Yellow River in China. Based on a model controlling for both population structure (Q) and relative kinship (K), three SSR markers (GCPM_616-1 in 31.2 Mb on LG I, GCPM_4055-2 in 5.7 Mb on LG XV, and GCPM_3142 of unknown location) were identified for seven traits. GCPM_616-1 was associated with five morphological traits (R2 = 5.14-10.09%), whereas GCPM_3142 (15.03%) and GCPM_4055-2 (13.26%) were associated with one morphological trait and one physiological trait, respectively. CONCLUSIONS: The results suggest that this wild population is suitable for association mapping and the identified markers will be suitable for marker-assisted selection breeding or detection of target genes or QTL in the near future.


Assuntos
Mapeamento Cromossômico , Marcadores Genéticos , Populus/genética , Locos de Características Quantitativas , China , Genética Populacional , Genótipo , Repetições de Microssatélites , Modelos Genéticos , Fenótipo , Populus/fisiologia
14.
Materials (Basel) ; 17(14)2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39063774

RESUMO

The quartz sand-enhanced coagulation (QSEC) is an improved coagulation method for treating water, which uses quartz sand as a heavy medium to accelerate the sedimentation rate of flocs and reduce the sedimentation time. The factors that influence the QSEC effect and can be controlled manually include the quartz sand dosage, coagulant dosage, sewage pH, stirring time, settling time, etc., and their reasonable setting is critical to the result of water treatment. This paper aimed to study the optimal conditions of QSEC; first, single-factor tests were conducted to explore the optimal range of influencing factors, followed by response surface methodology (RSM) tests to accurately determine the optimum values of significant factors. The results show that the addition of quartz sand did not improve the water quality of the coagulation treatment, it took only 140 s for the floc to sink to the bottom, and the sediment volume only accounted for 12.2% of the total sewage. The quartz sand dosage, the coagulant dosage, and sewage pH all had a significant impact on the coagulation effect, and resulted in inflection points. A QSEC-guiding model was derived through RSM tests, and subsequent model optimization and experimental validation revealed the optimal conditions for treating domestic sewage as follows: the polyaluminum chloride (PAC) dosage, cationic polyacrylamide (CPAM) dosage, the sewage pH, quartz sand dosage, stirring time, and settling time were 0.97 g/L, 2.25 mg/L, 7.22, 2 g/L, 5 min, and 30 min, respectively, and the turbidity of the treated sewage was reduced to 1.15 NTU.

15.
J Hazard Mater ; 469: 134085, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38522197

RESUMO

Composite pollution by microplastics and heavy metals poses a potential threat to the soilplant system and has received increasing attention. Plant growth-promoting bacteria (PGPB) have good application potential for the remediation of combined microplastic and heavy metal pollution, but few related studies exist. The present study employed a pot experiment to investigate the effects of inoculation with the PGPB Bacillus sp. SL-413 and Enterobacter sp. VY-1 on sorghum growth and Cd accumulation under conditions of combined cadmium (Cd) and polyethylene (PE) pollution. Cd+PE composite contamination led to a significant reduction in sorghum length and biomass due to increased toxicity. Inoculation with Bacillus sp. SL-413 and Enterobacter sp. VY-1 alleviated the stress caused by Cd+PE complex pollution, and the dry weight of sorghum increased by 25.7% to 46.1% aboveground and by 12.3% to 45.3% belowground. Bacillus sp. SL-413 and Enterobacter sp. VY-1 inoculation increased the Cd content and accumulation in sorghum and improved the phytoremediation efficiency of Cd. The inoculation treatment effectively alleviated the nutrient stress caused by the reduction in soil mineral nutrients due to Cd+PE composite pollution. The composition of the soil bacterial communities was also affected by the Cd, Cd+PE and bacterial inoculation treatments, which affected the diversity of the soil bacterial communities. Network analyses indicated that bacterial inoculation regulated the interaction of rhizospheric microorganisms and increased the stability of soil bacterial communities. The Mantel test showed that the changes in the soil bacterial community and function due to inoculation with Bacillus sp. SL-413 and Enterobacter sp. VY-1 were important factors influencing sorghum growth and Cd remediation efficiency. The results of this study will provide new evidence for the research on joint plantmicrobe remediation of heavy metal and microplastic composite pollution.


Assuntos
Bacillus , Metais Pesados , Poluentes do Solo , Sorghum , Cádmio/análise , Biodegradação Ambiental , Plásticos , Polietileno , Solo , Rizosfera , Microplásticos , Metais Pesados/toxicidade , Metais Pesados/análise , Enterobacter , Poluentes do Solo/análise
16.
Microorganisms ; 12(5)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38792702

RESUMO

The green and efficient remediation of soil cadmium (Cd) is an urgent task, and plant-microbial joint remediation has become a research hotspot due to its advantages. High-throughput sequencing and metabolomics have technical advantages in analyzing the microbiological mechanism of plant growth-promoting bacteria in improving phytoremediation of soil heavy metal pollution. In this experiment, a pot trial was conducted to investigate the effects of inoculating the plant growth-promoting bacterium Enterobacter sp. VY on the growth and Cd remediation efficiency of the energy plant Hybrid pennisetum. The test strain VY-1 was analyzed using high-throughput sequencing and metabolomics to assess its effects on microbial community composition and metabolic function. The results demonstrated that Enterobacter sp. VY-1 effectively mitigated Cd stress on Hybrid pennisetum, resulting in increased plant biomass, Cd accumulation, and translocation factor, thereby enhancing phytoremediation efficiency. Analysis of soil physical-chemical properties revealed that strain VY-1 could increase soil total nitrogen, total phosphorus, available phosphorus, and available potassium content. Principal coordinate analysis (PCoA) indicated that strain VY-1 significantly influenced bacterial community composition, with Proteobacteria, Firmicutes, Chloroflexi, among others, being the main differential taxa. Redundancy analysis (RDA) revealed that available phosphorus, available potassium, and pH were the primary factors affecting bacterial communities. Partial Least Squares Discriminant Analysis (PLS-DA) demonstrated that strain VY-1 modulated the metabolite profile of Hybrid pennisetum rhizosphere soil, with 27 differential metabolites showing significant differences, including 19 up-regulated and eight down-regulated expressions. These differentially expressed metabolites were primarily involved in metabolism and environmental information processing, encompassing pathways such as glutamine and glutamate metabolism, α-linolenic acid metabolism, pyrimidine metabolism, and purine metabolism. This study utilized 16S rRNA high-throughput sequencing and metabolomics technology to investigate the impact of the plant growth-promoting bacterium Enterobacter sp. VY-1 on the growth and Cd enrichment of Hybrid pennisetum, providing insights into the regulatory role of plant growth-promoting bacteria in microbial community structure and metabolic function, thereby improving the microbiological mechanisms of phytoremediation.

17.
New Phytol ; 197(3): 763-776, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23278184

RESUMO

Chinese white poplar (Populus tomentosa), an important commercial tree species for timber and pulp production in northern China, has been used to examine the individual genes and allelic diversity responsible for complex traits controlling growth and lignocellulosic biosynthesis. Taking advantage of the low degree of linkage disequilibrium (LD) within P. tomentosa association populations, we examined associations between 15 cellulose synthase (PtoCesA) genes and traits including growth and wood properties. Thirty-six novel simple sequence repeat (SSR) markers within PtoCesA genes were detected by re-sequencing and genotyped in an association population (460 individuals). Single-marker and haplotype-based LD approaches were used to identify significant marker-trait associations. Family-based linkage studies and real-time PCR testing were conducted to validate the functional significance of SSR variation. Fifteen single-marker associations from seven PtoCesA genes and nine haplotype-based associations within six genes were identified in the association population (false discovery rate Q < 0.05). Next, five SSR marker-trait associations (Q < 0.05) from four PtoCesA genes were successfully validated in a linkage mapping population (1200 individuals). The results imply a functional role for these genes in mediating wood properties, demonstrating the potential of combining single-marker and haplotype-based LD approaches to detect functional allelic variation underlying quantitative traits in a low-LD population.


Assuntos
Glucosiltransferases/genética , Repetições de Microssatélites , Populus/genética , Alelos , Mapeamento Cromossômico , Estudos de Associação Genética , Marcadores Genéticos , Glucosiltransferases/química , Haplótipos , Lignina/biossíntese , Desequilíbrio de Ligação , Populus/anatomia & histologia , Populus/crescimento & desenvolvimento
18.
J Environ Manage ; 128: 192-203, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23747370

RESUMO

The way in which disturbances from human land use are patterned in space across scales can have important consequences for efforts to govern human/environment with regard to, but not only, invasive spread-dispersal processes. In this context, we explore the potential of disturbance patterns along a continuum of scales as proxies for identifying the geographical regions prone to spread of invasive plant species. To this end, we build on a previous framework of cross-scale disturbance patterns, exercising the approach for the Apulia region (South Italy). We first review procedures and results introducing disturbance maps and sliding windows to measure composition (amount) and configuration (contagion) of disturbance patterns both for real and simulated landscapes from random, multifractal and hierarchical neutral models. We introduce cross-scale disturbance profiles obtained by clustering locations from real and simulated landscapes, which are used as foils for comparison to the real landscapes on the same pattern transition space. Critical percolation thresholds derived from landscape observations and theoretical works are discussed in order to identify critical scale domains. With reference to the actual land use and invasive alien flora correlates of disturbance patterns, a cross-scale "invasibility" map of the Apulia region is derived, which shows sub-regions and scale domains with different potentials for the invasive spread of undesirable species. We discuss the potential effect of contagious and non-contagious disturbances like climate change and why multifractal-like disturbance patterns might be more desirable than others to counter biological invasions in a multi-scale and multi-level context of adaptive planning, design and management of disturbance.


Assuntos
Espécies Introduzidas , Modelos Teóricos , Plantas , Mudança Climática , Análise por Conglomerados , Simulação por Computador , Conservação dos Recursos Naturais , Ecossistema , Humanos , Itália , Técnicas de Planejamento
19.
Sci Total Environ ; 900: 165608, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474064

RESUMO

Small floodgates in the river network area own some characteristics: considerable quantity, wide range and short adjustment time, and intercepts the one-dimensional constant flow of rivers, which induce a great impact on riverine water quality. In this study, a typical urban floodgate-controlled reach was selected, and analyzed through the monthly data of four pollutant indicators TN, TP, CODMn and NH3-N at six sampling sites S1-S6 in 2016-2018. The principal component analysis and correlation analysis showed that TP was a representative indicator and there was a positive correlation between various pollutants. The difference test and linear regression showed that the concentration of pollutants at different sampling points varied greatly, and the pollutant concentrations in the longitudinal direction of the river showed a cubic-linear regression. The cluster system and CCME WQI showed that the water quality in the urban floodgate-controlled reach is "marginal" state, and TN and NH3-N are severely exceeding the standard. The "cumulative changes" of the floodgate on the pollutant input to the environment appeared spatial heterogeneity.

20.
Chemosphere ; 311(Pt 2): 136926, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36272625

RESUMO

Acid mine drainage (AMD) is the term used to describe drainage from coal mines with high sulfur-bearing rocks. The oxidative weathering of metal sulfides leads to AMD. The acidic environment corrodes more harmful compounds in the soil, which is spread throughout the working area. One such significant metal is copper, which is extracted in massive quantities from ores rich in sulfide. A copper-extraction resin might be created by combining diatomaceous earth (DE) particles with polyethyleneimine (PEI), which is shown to have great selectivity and affinity for copper. In this effort, PEI-DE particles' copper absorption level was examined by using synthetic and actual acid mine drainage samples at varied pH values. The findings of the copper uptake particles have been examined through the Support Vector Machine (SVM) model. Using the n-fold 14 cross-validation approach, the quantities of parameters and C are estimated to be 0.001 and 0.01, respectively. The SVM analysis was correct, and the findings indicated that copper could bind to the material efficiently and preferentially at pH 4. Subsequent water elution studies at a pH value of 1 confirmed the pH-reliant interaction between dissolved Cu and PEI by demonstrating full release of the adsorbed Cu. In this research, the copper absorption of PEI-DE particles from synthetic and genuine AMD specimens was studied based on several pH conditions. The findings suggest that copper may attach to the material effectively and preferentially at pH 4. Studies of filtering water at pH1 later confirmed that all of the adsorbed Cu was released. This shows that the interaction between PEI and dissolved Cu depends on PH.


Assuntos
Cobre , Poluentes Químicos da Água , Cobre/análise , Água , Metais/análise , Mineração , Poluentes Químicos da Água/análise , Aprendizado de Máquina
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