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1.
PLoS One ; 19(5): e0298410, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758951

RESUMO

In the context of the digital information era, the impact of "The Internet Plus," "Big Data," and other technologies on urban social development has been far beyond any preceding era, under the influence of information technology, urban agglomeration space exhibits a new layout. Based on the search engine data of eleven cities in the Guangdong-Hong Kong-Macao Greater Bay Area from 2012 to 2021, this research constructs the inter-city information network strength linkage matrix to examine the evolution characteristics of city network structure and its driving causes. The results reveal that (1) the overall information linkage strength exhibits a pattern of steadily growing the radiating effect from the leading cities of Guangdong, Shenzhen, and Hong Kong to the surrounding cities, and a closer and more balanced information linkage network is gradually built. (2) Guangzhou-Shenzhen-Hong Kong-Guangdong-Hong Kong-Macao Greater Bay Area information linkage absolute control advantage, four cities Foshan, Dongguan, Zhuhai, Macao regional hub position steadily highlighted. The entire information connection network of the urban agglomerations tends to be flat and polycentric at the same time. (3) The regional core-edge hierarchy is well established, with the four cities of Guangzhou, Dongguan, Shenzhen, and Hong Kong creating a northwest-southeast orientation. The core metropolis regions of Guangdong, Hong Kong, and Macao in the Greater Bay Area increasingly exert a radiation spreading effect to the northeast and southwest. (4) The urban economy, transportation distance, and information infrastructure have substantial effects on the information connection intensity network of urban clusters.


Assuntos
Cidades , Hong Kong , China , Humanos , Macau , Baías
3.
Behav Neurol ; 2023: 7017106, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37383091

RESUMO

Methods: Gene expression profiles and apoptosis-related data were downloaded from the Gene Expression Omnibus and Molecular Signature databases, respectively. Apoptosis-related differentially expressed mRNAs (DEGs) and miRNAs (DEMs) from blood samples between the schizophrenia and healthy control individuals were screened. A diagnostic model was developed using the data from univariate and least absolute shrinkage and selection operator (LASSO) regression analyses, followed by validation using the GSE38485 dataset. Cases were divided into low-risk (LR) and high-risk (HR) groups based on the risk score of the model, and differences in immune gene sets and pathways between these two groups were compared. Finally, a ceRNA network was constructed by integrating long non-coding RNAs (lncRNAs), DEMs, and DEGs. Results: A diagnostic model containing 15 apoptosis-related genes was developed and its diagnostic efficiency was found to be robust. The HR group was correlated with higher immune scores of chemokines, cytokines, and interleukins; it was also significantly involved in pathways such as pancreatic beta cells and early estrogen response. A ceRNA network composed of 2 lncRNAs, 14 miRNAs, and 5 mRNAs was established. Conclusions: The established model is a potential tool to improve the diagnostic efficiency of patients with schizophrenia, and the nodes included in the ceRNA network might serve as biomarkers and therapeutic targets for schizophrenia.


Assuntos
MicroRNAs , RNA Longo não Codificante , Esquizofrenia , Humanos , RNA Longo não Codificante/genética , Esquizofrenia/genética , MicroRNAs/genética , Apoptose/genética , Bases de Dados Factuais , RNA Mensageiro/genética
4.
Altern Ther Health Med ; 29(5): 268-273, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37083647

RESUMO

Objective: To compare and analyze the effects of proximal femoral nail anti-rotation (PFNA) and femoral head replacement in treating elderly patients with femoral intertrochanteric fracture. Methods: A retrospective analysis was performed on clinical data of elderly patients with femoral intertrochanteric fractures from February 2019 to February 2021 in the hospital. Patients were divided into a control group (PFNA) and a study group (femoral head replacement) based on surgical methods after propensity score matching. Perioperative indicators, hematocrit (HCT), hemoglobin (Hb), hip function, and complications one year after surgery were compared between the two groups after excluding confounding factors. Result: Both groups had complete follow-ups without any cases lost. The study group had longer surgical time, higher intraoperative blood loss, and greater postoperative drainage volume compared to the control group, while the hospital stay and weight-bearing starting time were shorter in the study group (P < .05). There were statistically significant differences in HCT and Hb after surgery between the two groups (P < .05). One year after surgery, the excellent and good rate of hip function was 90.28% in the study group and 76.39% in the control group (P < .05). The total incidence rate of postoperative early complications was higher in the study group, while the total incidence rate of late postoperative complications was lower in the study group compared to the control group (P < .05). Conclusion: PFNA and femoral head replacement have their respective advantages in treating elderly patients with femoral intertrochanteric fractures. PFNA causes less trauma to patients but has poorer postoperative hip function recovery, while femoral head replacement causes greater trauma to patients but has better postoperative hip function recovery. Therefore, the appropriate surgical method can be selected based on the patient's specific conditions.


Assuntos
Fraturas do Fêmur , Fixação Intramedular de Fraturas , Fraturas do Quadril , Humanos , Idoso , Estudos Retrospectivos , Cabeça do Fêmur , Pinos Ortopédicos , Fixação Intramedular de Fraturas/métodos , Resultado do Tratamento , Fraturas do Quadril/cirurgia , Fraturas do Fêmur/cirurgia , Complicações Pós-Operatórias/epidemiologia
5.
BMC Genom Data ; 24(1): 22, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-37061663

RESUMO

BACKGROUND: Previous reports revealed that a history of major depressive disorder (MDD) increased the risk of Alzheimer's disease (AD). The immune disorder is associated with MDD and AD pathophysiology. We aimed to identify differentially expressed immune-related genes (DEIRGs) that are involved in the pathogenesis of MDD and AD. METHODS: We downloaded mRNA expression profiles (GSE76826 and GSE5281) from the Gene Expression Omnibus (GEO) database. The R software was used to identify DEIRGs for the two diseases separately. Functional enrichment analysis and PPI network of DEIRGs were performed. Finally, the relationship between shared DEIRGs and immune infiltrates of AD and MDD were analyzed, respectively. RESULTS: A total of 121 DEIRGs linking AD and MDD were identified. These genes were significantly enriched in immune-related pathways, such as the JAK-STAT signaling pathway, regulation of chemotaxis, chemotaxis, cytokine-cytokine receptor interaction, and primary immunodeficiency. Furthermore, three shared DEIRGs (IL1R1, CHGB, and NRG1) were identified. Correlation analysis between DEIRGs and immune cells revealed that IL1R1 and NRG1 had a negative or positive correlation with some immune cells both in AD and MDD. CONCLUSION: Both DEIRGs and immune cell infiltrations play a vital role in the pathogenesis of AD and MDD. Our findings indicated that there are common genes and biological processes between MDD and AD, which provides a theoretical basis for the study of the comorbidity of MDD and AD.


Assuntos
Doença de Alzheimer , Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/genética , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Biologia Computacional , Mapas de Interação de Proteínas/genética , Biomarcadores
6.
Ecol Lett ; 26(5): 765-777, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36958933

RESUMO

Forest soil CO2 efflux (FCO2 ) is a crucial process in global carbon cycling; however, how FCO2 responds to disturbance regimes in different forest biomes is poorly understood. We quantified the effects of disturbance regimes on FCO2 across boreal, temperate, tropical and Mediterranean forests based on 1240 observations from 380 studies. Globally, climatic perturbations such as elevated CO2 concentration, warming and increased precipitation increase FCO2 by 13% to 25%. FCO2 is increased by forest conversion to grassland and elevated carbon input by forest management practices but reduced by decreased carbon input, fire and acid rain. Disturbance also changes soil temperature and water content, which in turn affect the direction and magnitude of disturbance influences on FCO2 . FCO2 is disturbance- and biome-type dependent and such effects should be incorporated into earth system models to improve the projection of the feedback between the terrestrial C cycle and climate change.


Assuntos
Dióxido de Carbono , Solo , Florestas , Ecossistema , Carbono
7.
Glob Chang Biol ; 29(7): 1922-1938, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36607160

RESUMO

Responses of the terrestrial biosphere to rapidly changing environmental conditions are a major source of uncertainty in climate projections. In an effort to reduce this uncertainty, a wide range of global change experiments have been conducted that mimic future conditions in terrestrial ecosystems, manipulating CO2 , temperature, and nutrient and water availability. Syntheses of results across experiments provide a more general sense of ecosystem responses to global change, and help to discern the influence of background conditions such as climate and vegetation type in determining global change responses. Several independent syntheses of published data have yielded distinct databases for specific objectives. Such parallel, uncoordinated initiatives carry the risk of producing redundant data collection efforts and have led to contrasting outcomes without clarifying the underlying reason for divergence. These problems could be avoided by creating a publicly available, updatable, curated database. Here, we report on a global effort to collect and curate 57,089 treatment responses across 3644 manipulation experiments at 1145 sites, simulating elevated CO2 , warming, nutrient addition, and precipitation changes. In the resulting Manipulation Experiments Synthesis Initiative (MESI) database, effects of experimental global change drivers on carbon and nutrient cycles are included, as well as ancillary data such as background climate, vegetation type, treatment magnitude, duration, and, unique to our database, measured soil properties. Our analysis of the database indicates that most experiments are short term (one or few growing seasons), conducted in the USA, Europe, or China, and that the most abundantly reported variable is aboveground biomass. We provide the most comprehensive multifactor global change database to date, enabling the research community to tackle open research questions, vital to global policymaking. The MESI database, freely accessible at doi.org/10.5281/zenodo.7153253, opens new avenues for model evaluation and synthesis-based understanding of how global change affects terrestrial biomes. We welcome contributions to the database on GitHub.


Assuntos
Dióxido de Carbono , Ecossistema , Biomassa , Mudança Climática , Clima , Solo
8.
Molecules ; 27(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558096

RESUMO

In this study, the calcium gangue material calcite (−10 µm) was used to investigate the effects of different kinds of metal ions and dosages on the dispersion behavior of calcite. The test results showed that the dispersion behavior of calcite was poor under strongly alkaline conditions without the addition of metal ions, and the reason for that was calcite dissolved ions. The degree of influence of different metal ions on calcite dispersion behavior was Fe3+ > Mg2+ > Na+. The three metal ion dosage tests showed that the dispersion behavior of calcite became poorer with the increase of metal ion dosage. This mainly showed that with the increase of Na+ dosage, the trend of the dispersion behavior of calcite was not obvious, but with the increase of Fe3+ and Mg2+ dosage, the trend of calcite dispersion behavior changed more. The dispersion behavior of calcite was devastated by 5 × 10−4 mol/L Fe3+ at pH = 4−12. The different mechanisms of the three metal ions were identified by zeta potential, solution chemistry, and XPS analysis. Na+ only changed the zeta potential value of the calcite surface, which acted as a compressed electric double layer. However, the formation of metal hydroxide species or metal hydroxide surface precipitation due to the adsorption of Fe3+ and Mg2+ on the mineral surface resulted in the change of the dispersion behavior of calcite.


Assuntos
Cálcio , Minerais , Carbonato de Cálcio , Hidróxidos
9.
Molecules ; 27(24)2022 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-36558159

RESUMO

The efficient dispersion of particles is a prerequisite for the efficient flotation of fine smithsonite. However, unavoidable ions (Ca2+) in the pulp have become a challenge for the efficient separation of fine smithsonite, due to the high content of pulp and small radius of hydrated ions. Therefore, the dispersion behavior and mechanism of Ca2+ action on smithsonite are important for improving the efficiency of smithsonite flotation. In this study, the effects of Ca2+ on the dispersion behavior of fine smithsonite were studied using a turbidity test. The results showed that the dispersion behavior of smithsonite was good in the absence of Ca2+ at a range of pH = 4−12. However, the measured turbidity values of smithsonite decreased with the addition of calcium ions. In particular, the dispersion behavior of smithsonite became worse at pH > 10. Zeta potential test results showed that the smithsonite's surface potential shifted positively, and the absolute value of potential decreased in the presence of Ca2+. The results of X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) analysis showed that calcium ions were adsorbed on the smithsonite surface, which may have caused ion exchange or the generation of calcium hydroxide precipitation leading to particle coalescence behavior. The calculations of solution chemistry and DLVO theory indicated that calcium ions adsorbed on the surface of smithsonite to form Ca(OH)+ or precipitation, which reduced the potential energy of interparticle interactions and led to the disruption of dispersion behavior of smithsonite.


Assuntos
Cálcio , Cálcio/química , Íons , Microscopia Eletrônica de Varredura , Troca Iônica
10.
Acta Biochim Pol ; 69(1): 65-69, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35129942

RESUMO

In the present study isoxanthanol was investigated for treatment of monosodium iodoacetate (MIA)-induced osteoarthritis (OA) in vivo. The study demonstrated that isoxanthanol inhibited excessive release of interleukin-6, NO and PGE2 in RAW264.7 cells treated with LPS in dose dependent manner. The effects of isoxanthanol were examined in a rat model of osteoarthritis (OA) and observed to amelio-rate inflammatory damage and protect against OA. Moreover, in vivo data also confirmed inhibition of interleukin-6, NO and PGE2 levels in LPS-induced OA-rats. Deterioration of knee subchondral bone in LPS-induced OA-rats was also prevented effectively by isoxanthanol-treatment. Therefore, isoxanthanol prevents subchondral bone deterioration in OA rats via targeting inflammatory processes.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Osteoartrite/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Artrite Experimental/metabolismo , Osso e Ossos/metabolismo , Dinoprostona/metabolismo , Modelos Animais de Doenças , Interleucina-6/metabolismo , Masculino , Camundongos , Óxido Nítrico/metabolismo , Osteoartrite/metabolismo , Substâncias Protetoras/farmacologia , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Sesquiterpenos/farmacologia , Xanthium/química
11.
Front Psychol ; 13: 1075636, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36591087

RESUMO

Background: Mounting studies have reported altered neuroimaging features in generalized anxiety disorder (GAD). However, little is known about changes in degree centrality (DC) as an effective diagnostic method for GAD. Therefore, we aimed to explore the abnormality of DCs and whether these features can be used in the diagnosis of GAD. Methods: Forty-one GAD patients and 45 healthy controls participated in the study. Imaging data were analyzed using DC and receiver operating characteristic (ROC) methods. Results: Compared with the control group, increased DC values in bilateral cerebellum and left middle temporal gyrus (MTG), and decreased DC values in the left medial frontal orbital gyrus (MFOG), fusiform gyrus (FG), and bilateral posterior cingulate cortex (PCC). The ROC results showed that the DC value of the left MTG could serve as a potential neuroimaging marker with high sensitivity and specificity for distinguishing patients from healthy controls. Conclusion: Our findings demonstrate that abnormal DCs in the left MTG can be observed in GAD, highlighting the importance of GAD pathophysiology.

12.
ACS Omega ; 6(49): 33607-33613, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34926908

RESUMO

Semi-industrial tests were conducted to investigate the feasibility and efficiency of a combined column and mechanical flotation cell process for the beneficiation of Sanshandao low-grade gold ore. The results showed that the performance of the combined flotation process of the cyclonic-static microbubble flotation column (FCSMC) and mechanical flotation cells was superior to that of the mechanical flotation cell, while the flowsheet was simplified. FCSMC is efficient when used on fine particles, whereas a mechanical flotation cell is effective for coarse particles. Thus, the combined flotation process exhibited a better separation performance by employing the strengths of both methods. The use of the combined FCSMC and cell flotation process showed promising results for a producing grade of 48.24 g/t gold with 96.13% recovery. The combined column and cell flotation process introduces a new approach for the separation of low-grade gold ore.

13.
Front Microbiol ; 12: 719725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34790175

RESUMO

A tight association between microbial function and taxonomy is the basis of functional prediction based on taxonomy, but such associations have been controversial in water biomes largely due to the probable prevalence of functional redundancy. However, previous studies on this topic used a relatively coarse resolution of ecosystem functioning, potentially inflating the estimated functional redundancy. Thus, a comprehensive evaluation of the association between high-resolution functional traits and taxonomic diversity obtained from fresh and saline water metagenomic data is urgently needed. Here, we examined 938 functionally and taxonomically annotated water metagenomes obtained worldwide to scrutinize the connection between function and taxonomy, and to identify the key driver of water metagenomes function or taxonomic composition at a global scale. We found that pairwise similarity of function was significantly associated with taxonomy, though taxonomy had higher global dissimilarity than function. Classification into six water biomes resulted in greater variation in taxonomic compositions than functional profiles, as the key regulating factor was salinity. Fresh water microbes harbored distinct functional and taxonomic structures from microbes in saline water biomes, despite that taxonomy was more susceptible to gradient of geography and climate than function. In summary, our results find a significant relationship between taxonomic diversity and microbial functioning in global water metagenomes, although microbial taxonomic compositions vary to a larger extent than functional profiles in aquatic ecosystems, suggesting the possibility and necessity for functional prediction of microorganisms based on taxonomy in global aquatic ecosystems.

14.
Int J Mol Sci ; 22(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34681733

RESUMO

Anthocyanin is a type of flavonoid pigment widely present in fruits and vegetables. It can not only be used as natural pigment, but also has a variety of health functions, for instance, anti-oxidant, anti-inflammatory, anti-tumor, and neuroprotective activities. Persistent proinflammatory status is a major factor in the development, progression, and complications of chronic diseases. Not surprisingly, there are thus many food ingredients that can potentially affect inflammation related diseases and many studies have shown that anthocyanins play an important role in inflammatory pathways. In this paper, the inflammation related diseases (such as, obesity, diabetes, cardiovascular disease, and cancer) of anthocyanins are introduced, and the anti-inflammatory effect of anthocyanins is emphatically introduced. Moreover, the anti-inflammatory mechanism of anthocyanins is elaborated from the aspects of NF-κB, toll like receptor, MAPKs, NO, and ROS and the main efficacy of anthocyanins in inflammation and related diseases is determined. In conclusion, this review aims to get a clear insight into the role of anthocyanins in inflammation related diseases.


Assuntos
Antocianinas/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Inflamação/complicações , Animais , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/etiologia , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/etiologia , Dinoprostona/metabolismo , Humanos , Inflamação/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Obesidade/tratamento farmacológico , Obesidade/etiologia
15.
Molecules ; 26(17)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34500800

RESUMO

Separating oxidized zinc minerals from flotation tailings is always a challenge. In this study, a flotation tailing from Wulagen zinc mine in China (Zn grade < 1%) was processed using froth flotation with combinations of amines (OPA 10, OPA 1214, OPA 13, DDA) and Na2S to study the effects of these amines on the zinc recovery as well as their interactions with other reagents, aiming to screen out a proper reagent scheme to improve zinc separation from extremely low-grade zinc flotation tailings. The results show that different amines led to different flotation performance, and the collectors were ranked as OPA 1214, OPA 13, OPA 10 and DDA in a decreasing order based on flotation collectivity and selectivity. An increase in the concentration of each collector increased the zinc recovery but reduced the concentrate zinc grade. Interactions were also observed between different amines and Na2S and Na2SiO3, and OPA 1214 outdid the others in saving the usage of both the Na2S and Na2SiO3. The measured adsorption of collector onto smithsonite was found to correlate well with flotation test results. It was concluded that hydrocarbon chains can be held accountable for the difference in the flotation performance with different amines. The longer the hydrocarbon chain, the stronger the hydrophobic association ability of amine, which is conducive to the selective amine adsorption onto sulfurized smithsonite particles and hence the smithsonite flotation.

16.
Sci Total Environ ; 796: 148975, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34271393

RESUMO

Adaptive multi-paddock (AMP) grazing, a grazing system in which individual paddocks are grazed for a short duration at a high stock density and followed by a long rest period, is claimed to be an effective tool to sustainably manage and improve grasslands and enhance their ecosystem services. However, whether AMP grazing is superior to conventional grazing (n-AMP) in reducing soil greenhouse gas (GHG) emissions is unclear. Here, we measured CO2, CH4, and N2O fluxes between August 2017 and August 2019 in 12 pairs of AMP vs. n-AMP ranches distributed across an agro-climatic gradient in Alberta, Canada. We found that field GHG fluxes did not differ between AMP and n-AMP grazing systems, but instead were regulated by specific management attributes, environmental conditions, and soil properties, including cattle stocking rate, cultivation history, soil moisture content, and soil bulk density. Specifically, we found that seasonal mean CO2 emissions increased with increasing cattle stocking rates, while CH4 uptake was lower in grasslands with a history of cultivation. Seasonal mean CO2 emissions increased while CH4 uptake decreased with increasing soil moisture content. In addition, CH4 uptake decreased with increasing soil bulk density. Observed N2O emissions were poorly predicted by the management, environmental conditions, and soil properties investigated in our study. We conclude that AMP grazing does not have an advantage over n-AMP grazing in reducing GHG fluxes from grasslands. Future efforts to develop optimal management strategies (e.g., the use of sustainable stocking rates and avoided cultivation) that reduce GHG emissions should also consider the environmental conditions and soil properties unique to every grassland ecosystem.


Assuntos
Gases de Efeito Estufa , Alberta , Animais , Dióxido de Carbono/análise , Bovinos , Ecossistema , Pradaria , Gases de Efeito Estufa/análise , Metano/análise , Óxido Nitroso/análise , Solo
17.
Sci Total Environ ; 771: 144779, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33736125

RESUMO

Plant invasion can markedly alter soil fungal communities and nitrogen (N) availability; however, the linkage between the fungal decomposition capacity and N mineralization during plant invasion remains largely unknown. Here, we examined the relationship between net mineralization rates and relevant functional genes, as well as fungal species composition and function following Moso bamboo (Phyllostachys edulis) invasion of evergreen broadleaf forests, by studying broadleaf forests (non-invaded), mixed bamboo-broadleaf forests (moderately invaded) and bamboo forests (heavily invaded). Fungal species composition and functional genes involved in organic matter decomposition (laccase and cellobiohydrolase), N mineralization (alkaline peptidases) and nitrification (ammonia monooxygenase) were determined via high-throughput sequencing and real-time PCR. Both net ammonification and nitrification rates were generally increased with bamboo invasion into the broadleaf forest, where the net ammonification rate, on average, was 10.8 times higher than the nitrification rate across the three forest types. The fungal species composition and ecological guilds were altered with bamboo invasion, as demonstrated by the increased proportion of saprotrophs but decreased proportion of symbiotrophs in the bamboo forest. The increased net ammonification rate in bamboo forest was positively correlated with both fungal species composition and functional groups, and the fungal lcc gene (for lignin breakdown) abundance explained 67% of the variation of the net ammonification rate. In addition, the gene abundance of ammonia-oxidizing bacteria (AOB) explained 62% of the variation of net nitrification rate across the three forest types. The increased soil ammonification and nitrification rates following bamboo invasion of broadleaf forests suggest that the bamboo-invasion associated increase in soil N supply provided a positive feedback that facilitated bamboo invasion into broadleaf forests.


Assuntos
Nitrogênio , Solo , Florestas , Fungos/genética , Nitrogênio/análise , Poaceae , Microbiologia do Solo
18.
Commun Biol ; 4(1): 105, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483627

RESUMO

Coconut (Cocos nucifera) is the emblematic palm of tropical coastal areas all around the globe. It provides vital resources to millions of farmers. In an effort to better understand its evolutionary history and to develop genomic tools for its improvement, a sequence draft was recently released. Here, we present a dense linkage map (8402 SNPs) aiming to assemble the large genome of coconut (2.42 Gbp, 2n = 32) into 16 pseudomolecules. As a result, 47% of the sequences (representing 77% of the genes) were assigned to 16 linkage groups and ordered. We observed segregation distortion in chromosome Cn15, which is a signature of strong selection among pollen grains, favouring the maternal allele. Comparing our results with the genome of the oil palm Elaeis guineensis allowed us to identify major events in the evolutionary history of palms. We find that coconut underwent a massive transposable element invasion in the last million years, which could be related to the fluctuations of sea level during the glaciations at Pleistocene that would have triggered a population bottleneck. Finally, to better understand the facultative halophyte trait of coconut, we conducted an RNA-seq experiment on leaves to identify key players of signaling pathways involved in salt stress response. Altogether, our findings represent a valuable resource for the coconut breeding community.


Assuntos
Evolução Biológica , Cocos/genética , Genoma de Planta , Tolerância ao Sal/genética , Transdução de Sinais/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Elementos de DNA Transponíveis , Técnicas de Genotipagem , Padrões de Referência
19.
Sci Total Environ ; 752: 141958, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32892054

RESUMO

Biochar addition can reduce methane (CH4) emissions from paddy soils while the mechanisms involved are not entirely clear. Here, we studied the effect of biochar addition on CH4 emissions, and the abundance and community composition of methanogens and methanotrophs over two rice cultivation seasons. The experiment had the following five treatments: control (CK), chemical fertilizer application only (BC0), and 0.5% (w/w) (BC1), 1% (BC2), and 2% of biochar applied with chemical fertilizers (BC3). The season-wide CH4 emissions were decreased (P < 0.05) by 22.2-95.7% in biochar application compared with BC0 in the two rice seasons (2017 and 2018). In 2017, biochar application decreased methanogenic archaea (mcrA) but increased methanotrophic bacteria (pmoA) abundances, and decreased the ratio of mcrA/pmoA, as compared with BC0 (P < 0.05). In 2018, the abundance of mcrA was lower in BC2 and BC3 than in BC0 (P < 0.05) but was not different between BC0 and BC1, and the abundance of pmoA was lower in BC1, BC2 and BC3 than in BC0 (P < 0.05). The CH4 emissions were positively related to abundances of the mcrA gene (P < 0.01) but not to that of the pmoA gene in two rice seasons. Rice grain yield was increased by 62.2-94.1% in biochar addition treatments compared with BC0 in the first year (P < 0.01) and by 29.9-37.6% in BC2 and BC3 compared with BC0 in the second year (P < 0.05). Biochar application decreased CH4 emissions by reducing methanogenic archaea abundance in the studied flooded paddy soil.


Assuntos
Oryza , Solo , Archaea/genética , Carvão Vegetal , Metano , Microbiologia do Solo
20.
Biol Rev Camb Philos Soc ; 95(1): 167-183, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31625247

RESUMO

Soil organic carbon (SOC) is a valuable resource for mediating global climate change and securing food production. Despite an alarming rate of global plant diversity loss, uncertainties concerning the effects of plant diversity on SOC remain, because plant diversity not only stimulates litter inputs via increased productivity, thus enhancing SOC, but also stimulates microbial respiration, thus reducing SOC. By analysing 1001 paired observations of plant mixtures and corresponding monocultures from 121 publications, we show that both SOC content and stock are on average 5 and 8% higher in species mixtures than in monocultures. These positive mixture effects increase over time and are more pronounced in deeper soils. Microbial biomass carbon, an indicator of SOC release and formation, also increases, but the proportion of microbial biomass carbon in SOC is lower in mixtures. Moreover, these species-mixture effects are consistent across forest, grassland, and cropland systems and are independent of background climates. Our results indicate that converting 50% of global forests from mixtures to monocultures would release an average of 2.70 Pg C from soil annually over a period of 20 years: about 30% of global annual fossil-fuel emissions. Our study highlights the importance of plant diversity preservation for the maintenance of soil carbon sequestration in discussions of global climate change policy.

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