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1.
J Pept Sci ; 29(11): e3497, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37088557

RESUMO

Antimicrobial peptides and their analogues have become substitutes for antibiotics in recent years. The antimicrobial peptide analogue SAMP-A4-C8 (n-octanoic-VRLLRRRI) with high antimicrobial activity was found in our lab. We speculate that it may kill pathogens by some lethal mechanism of action. In the present investigation, the microbicidal activities of SAMP-A4-C8 and its mechanism of action were investigated. The results demonstrated that SAMP-A4-C8 had lethal activities against Staphylococcus aureus and Candida albicans by cell disruption. Based on its microbicidal activities, we believe that it is worth further research for its potential as drug candidate. The results showed that SAMP-A4-C8, with low propensity to induce the resistance of S. aureus and C. albicans, could kill the persister cells of S. aureus and C. albicans, exhibited biofilm forming inhibition activity and preformed biofilm eradication ability against S. aureus and C. albicans, and displayed therapeutic potential on pneumonia in S. aureus-infected mice by reducing lung inflammation. The present study provided a promising drug candidate in the war against multidrug resistance.


Assuntos
Anti-Infecciosos , Infecções Estafilocócicas , Animais , Camundongos , Staphylococcus aureus , Peptídeos Antimicrobianos , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Candida albicans , Biofilmes , Testes de Sensibilidade Microbiana
2.
Bioorg Chem ; 132: 106355, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36669359

RESUMO

Candida tropicalis is a major non-albicans species that causes invasive candidiasis. CGA-N12, an anti-Candida peptide found by our group, disrupted cell wall architecture by inhibiting the activity of the protein killer-resistant 9 (KRE9), a ß-1,6-glucan synthase specific to Candida spp. and plants. Herein, a set of CGA-N12 analogues were rationally designed based on the interaction networks between CGA-N12 and C. tropicalis KRE9 (CtKRE9). Seven CGA-N12 analogues with significantly improved antifungal activity against C. tropicalis were screened by reducing the docking energy of CGA-N12 and CtKRE9 and increasing the number of positive charges on CGA-N12 based on a stable three-dimensional model of CtKRE9. CGA-N12 and its analogues exhibited antifungal activity against C. tropicalis and its persist cells; they also inhibited biofilm formation and eradicated preformed biofilms. Compared with fluconazole, they displayed higher activities against the growth of persister cells and more effective preformed biofilm eradication. Among them, CGA-N12-0801, CGA-N12-0902 and CGA-N12-1002 displayed much higher activity and anti-proteinase digestion stability than CGA-N12. Specifically, CGA-N12-0801 was the optimal analogue, with a minimum inhibitory concentration of 3.46 µg/mL and a therapeutic index of 158.07. The results of electronic microscopy observations and KRE9 activity inhibition assays showed that CGA-N12 and its analogues killed C. tropicalis by disrupting the architecture of the cell wall and the integrity of the cell membrane. In conclusion, for the first time, we provide a simple and reliable method for the rational design of antimicrobial peptides and ideal candidates for treating Candida infections that not effectively eliminated by azole drugs.


Assuntos
Antifúngicos , Peptídeos , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Peptídeos/farmacologia , Peptídeos/metabolismo , Candida , Fluconazol/farmacologia , Candida tropicalis , Testes de Sensibilidade Microbiana , Biofilmes , Candida albicans
3.
J Pept Sci ; 27(10): e3352, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34028137

RESUMO

Infections with multidrug-resistant (MDR) pathogens are increasingly concerning for public health. Synthesized antimicrobial peptide A4 (SAMP-A4), a peptide computationally designed by our research team, is a potential drug candidate. However, the antimicrobial peptide SAMP-A4 is easily degraded in serum. To obtain SAMP-A4 analogues with high biostability, chemical modifications at its N-terminus, including fatty acid conjugation, glycosylation and PEGylation, were carried out. The results showed that the introduction of hydrophobic fatty acids at the N-terminus of SAMP-A4 is better than hydrophilic glycosylation and PEGylation. With increasing fatty acid chain length, the stability of SAMP-A4 analogues in serum and trypsin solutions is significantly improved, and the activities against MDR bacteria and Candida are significantly enhanced. There is no obvious change in haemolysis even when hexanoic acid is coupled with SAMP-A4, so the resulting analogue SAMP-A4-C6, SAMP-A4 conjugated with hexanoic acid, is the most likely of the analogues to become a drug.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Antibacterianos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases , Compostos de Fenilmercúrio
4.
Glob Chang Biol ; 22(2): 513-29, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26242490

RESUMO

Time series of environmental measurements are essential for detecting, measuring and understanding changes in the Earth system and its biological communities. Observational series have accumulated over the past 2-5 decades from measurements across the world's estuaries, bays, lagoons, inland seas and shelf waters influenced by runoff. We synthesize information contained in these time series to develop a global view of changes occurring in marine systems influenced by connectivity to land. Our review is organized around four themes: (i) human activities as drivers of change; (ii) variability of the climate system as a driver of change; (iii) successes, disappointments and challenges of managing change at the sea-land interface; and (iv) discoveries made from observations over time. Multidecadal time series reveal that many of the world's estuarine-coastal ecosystems are in a continuing state of change, and the pace of change is faster than we could have imagined a decade ago. Some have been transformed into novel ecosystems with habitats, biogeochemistry and biological communities outside the natural range of variability. Change takes many forms including linear and nonlinear trends, abrupt state changes and oscillations. The challenge of managing change is daunting in the coastal zone where diverse human pressures are concentrated and intersect with different responses to climate variability over land and over ocean basins. The pace of change in estuarine-coastal ecosystems will likely accelerate as the human population and economies continue to grow and as global climate change accelerates. Wise stewardship of the resources upon which we depend is critically dependent upon a continuing flow of information from observations to measure, understand and anticipate future changes along the world's coastlines.


Assuntos
Mudança Climática , Estuários , Atividades Humanas , Animais , Ecossistema , Humanos
5.
J Phycol ; 50(3): 602-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26988331

RESUMO

The ability of nutrient-deprived phytoplankton to recover in the short term when nutrients are resupplied has been studied for nitrogen and phosphorus, but the case for silicate (Si) is poorly understood. Si-limited Thalassiosira weissflogii (Grunow) Fryxell et Hasle (grown in batch culture) was harvested in stationary phase (when cell numbers stopped increasing ~2 d after Si depletion) and senescence (when cell numbers declined ~4 d after Si depletion) and Si was resupplied at different concentrations (from 0 to 100 µM). Cell numbers, proportion of dead cells, variable fluorescence emissions (Fv /Fm ), and activities of proteases were measured during Si depletion and for 24 h after Si resupply. As Si was depleted, the specific growth rate declined, dead cells increased from ~2% in log phase, to ~25% in stationary phase to over 35% in senescence, and activities of proteases associated with cell death increased several-fold. Concentration-dependent recovery of growth rate was seen after 24 h for cultures resupplied with Si in stationary phase but not in senescence. However, resupply of Si at 100 µM to stationary phase cultures alone increased protease activity to nearly the levels seen in senescence. Differences in the responses to Si resupply suggest that the ability and time to recover from Si depletion depend not only on the growth phase but also on the concentration resupplied.

6.
Mar Pollut Bull ; 200: 116079, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309179

RESUMO

Phosphorus is the most limiting nutrient in coastal waters of China, particularly in the Pearl River (PR) estuary. Rivers have different P forms including dissolved inorganic phosphorus (DIP), dissolved organic phosphorus (DOP), particulate inorganic phosphorus (PIP), and particulate organic phosphorus (POP). Their input to coastal seas has been overlooked. We hypothesize that DIP is a small fraction of total phosphorus (TP). We investigated these P forms and estimated their fluxes in PR eight outlets during 2015-2019. DIP on average is only a 30.90 % fraction of TP with PIP, POP and DOP accounting for 22.43, 31.56 and 15.37 %, respectively. The average annual fluxes of TP, DIP, DOP, PIP and POP were 12.58×, 3.34×, 1.68×, 3.19× and 4.26 × 106 mol/month, respectively, which are regulated by runoff and suspended particulate matter (SPM). The finding reveals the importance of other P forms for phytoplankton in the Pearl River estuary and their bio-availability deserves further study.


Assuntos
Estuários , Poluentes Químicos da Água , Fósforo/análise , Rios , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Matéria Orgânica Dissolvida , China
7.
Heliyon ; 10(8): e28976, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38628718

RESUMO

The massive consumption of fossil energy has resulted in high CO2 emissions, posing a formidable challenge to global sustainable economic development (SED). As countries endeavor to shift from fossil to clean energy sources to achieve SED, research on the impact of clean energy is scarce, and quantitative analysis is lacking. This study measured China's SED and used a spatial econometric model to examine the impact of clean energy consumption and production on SED across 30 provinces in China from 2008 to 2020. Results show that (1) China's SED exhibits significant positive spatial autocorrelation characteristics, forming a "point-to-area" development pattern. (2) Clean energy consumption, production, and consumption structure all contribute to the promotion of SED in the region and have positive spatial spillover effects. (3) A considerable regional disparity exists in the spatial impact of clean energy on SED. The eastern and central regions have significant positive spatial spillover effects, whereas the western region is opposite. Notably, the estimated coefficient of the spatial Durbin model is relatively small, reflecting China's ongoing transition to clean energy and its limited role in promoting economic sustainability. Joint efforts and differentiated policies are essential to develop clean energy and sustainable economic.

8.
Microbiol Spectr ; 12(1): e0203323, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38047693

RESUMO

IMPORTANCE: Reactive oxygen species (ROS), including superoxide anion, is a series of substances that cause oxidative stress for all organisms. Marine group II (MGII) archaea are mainly live in the surface seawater and exposed to considerable ROS. Therefore, it is important to understand the antioxidant capacity of MGII. Our research found that Fe/Mn- superoxide dismutase (Fe/MnSOD) may be more suitable for MGII to resist oxidative damage, and the changes in oxygen concentrations and SOD metallic cofactors play an important role in the selection of SOD by the 17 clades of MGII, which in turn affects the species differentiation of MGII. Overall, this study provides insight into the co-evolutionary history of these uncultivated marine archaea with the earth system.


Assuntos
Archaea , Oxigênio , Archaea/genética , Espécies Reativas de Oxigênio , Superóxido Dismutase/genética , Superóxidos
9.
Life Sci ; 350: 122767, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38843993

RESUMO

AIMS: Candida albicans is the most prevalent pathogenic fungus, exhibiting escalating multidrug resistance (MDR). Antimicrobial peptides (AMPs) represent promising candidates for addressing this issue. In this research, five antimicrobial peptides, ACP1 to ACP5 which named ACPs were studied as alternative fungicidal molecules. MAIN METHODS: CD assay was used to analyze the 2D structures, Absorbance method was used to test the antimicrobial activity, haemolytic activity, time-kill kinetics, biofilm inhibition and reduction activity, resistance induction activity and assessment against fluconazole-resistant C. albicans. SEM, TEM, CLSM, flow cytometer and FM were carried out to provide insight into the mechanisms of anti-Candida action. KEY FINDINGS: ACPs possessed an α-helical structure and strong anti-Candida activities, with minimum inhibitory concentrations (MICs) from 3.9 to 15.6 µg/mL. In addition, ACPs did not produce hemolysis at concentrations lower than 10 or 62 × MIC, indicating their low cytotoxicity. Fungicidal kinetics showed that they completely killed C. albicans within 8 h at 2 to 4 × MIC. Notably, ACPs were highly fungicidal against fluconazole-resistant C. albicans and showed low resistance. In addition, they were effective in inhibiting mycelium and biofilm formation. Fluorescence microscopy revealed that while fluconazole had minimal to no inhibitory effect on biofilm-forming cells, ACPs induced apoptosis in all of them. The research on mechanism of action revealed that ACPs disrupted the cell membranes, with ROS increasing and cellular mitochondrial membrane potential decreasing. SIGNIFICANCE: ACPs could be promising candidates for combating fluconazole-resistant C. albicans infections.


Assuntos
Antifúngicos , Peptídeos Antimicrobianos , Biofilmes , Candida albicans , Fluconazol , Testes de Sensibilidade Microbiana , Candida albicans/efeitos dos fármacos , Antifúngicos/farmacologia , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Fluconazol/farmacologia , Farmacorresistência Fúngica/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos
10.
Peptides ; 175: 171177, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38354953

RESUMO

Trichophyton mentagrophytes is a zoophilic dermatophyte that can cause dermatophytosis in humans and animals. Antimicrobial peptides (AMPs) are considered as a promising agent to overcome the drug-resistance of T. mentagrophytes. Our findings suggest that cationic antimicrobial peptide (ACP5) not only possesses stronger activity against T. mentagrophytes than fluconazole, but also shows lower toxicity to L929 mouse fibroblast cells than terbinafine. Notably, its resistance development rate after resistance induction was lower than terbinafine. The present study aimed to evaluate the fungicidal mechanism of ACP5 in vitro and its potential to treat dermatophyte infections in vivo. ACP5 at 1 ×MIC completely inhibited T. mentagrophytes spore germination in vitro. ACP5 severely disrupts the mycelial morphology, leading to mycelial rupture. Mechanistically, ACP5 induces excessive ROS production, damaging the integrity of the cell membrane and decreasing the mitochondrial membrane potential, causing irreversible damage in T. mentagrophytes. Furthermore, 1% ACP5 showed similar efficacy to the commercially available drug 1% terbinafine in a guinea pig dermatophytosis model, and the complete eradication of T. mentagrophytes from the skin by ACP5 was verified by tissue section observation. These results indicate that ACP5 is a promising candidate for the development of new agent to combat dermatophyte resistance.


Assuntos
Arthrodermataceae , Tinha , Humanos , Camundongos , Animais , Cobaias , Terbinafina/farmacologia , Terbinafina/uso terapêutico , Trichophyton , Tinha/tratamento farmacológico , Peptídeos Antimicrobianos , Antifúngicos/farmacologia , Fosfatase Ácida Resistente a Tartarato/farmacologia
11.
Interdiscip Sci ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416364

RESUMO

Efficient and precise design of antimicrobial peptides (AMPs) is of great importance in the field of AMP development. Computing provides opportunities for peptide de novo design. In the present investigation, a new machine learning-based AMP prediction model, AP_Sin, was trained using 1160 AMP sequences and 1160 non-AMP sequences. The results showed that AP_Sin correctly classified 94.61% of AMPs on a comprehensive dataset, outperforming the mainstream and open-source models (Antimicrobial Peptide Scanner vr.2, iAMPpred and AMPlify) and being effective in identifying AMPs. In addition, a peptide sequence generator, AP_Gen, was devised based on the concept of recombining dominant amino acids and dipeptide compositions. After inputting the parameters of the 71 tridecapeptides from antimicrobial peptides database (APD3) into AP_Gen, a tridecapeptide bank consisting of de novo designed 17,496 tridecapeptide sequences were randomly generated, from which 2675 candidate AMP sequences were identified by AP_Sin. Chemical synthesis was performed on 180 randomly selected candidate AMP sequences, of which 18 showed high antimicrobial activities against a wide range of the tested pathogenic microorganisms, and 16 of which had a minimal inhibitory concentration of less than 10 µg/mL against at least one of the tested pathogenic microorganisms. The method established in this research accelerates the discovery of valuable candidate AMPs and provides a novel approach for de novo design of antimicrobial peptides.

12.
Sci Adv ; 10(26): eadk6833, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38924405

RESUMO

Seamounts are ecological oases nurturing abundant fisheries resources and epibenthic megafauna in the vast oligotrophic ocean. Despite their significance, the formation mechanisms underlying these seamount ecological oases remain uncertain. To shed light on this phenomenon, this study conducted interdisciplinary in situ observations focusing on a shallow seamount in the oligotrophic ocean. The findings show that the seamount's topography interferes with the oceanic current to generate lee waves, effectively enhancing the nutrient supply to the euphotic layer downstream of the seamount. This continuous supply enhances phytoplankton biomass and subsequently the grazing and diurnal vertical migration of zooplankton, rapidly transporting the augmented phytoplankton biomass to the aphotic layer. Unlike the cyclonic eddies that move in the upper ocean, seamounts stand at fixed locations creating a more efficient and steady active transport loop. This active transport loop connects the euphotic and twilight zones, potentially conveying nourishment to benthic ecosystems to create stereoscopic oases in the oligotrophic ocean.


Assuntos
Ecossistema , Oceanos e Mares , Fitoplâncton , Zooplâncton , Animais , Biomassa , Movimentos da Água
13.
Environ Sci Pollut Res Int ; 30(10): 28066-28090, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36394815

RESUMO

As the global climate problem becomes increasingly serious, the green technology innovation to achieve "carbon peak and carbon neutral" has gradually become the global consensus of major countries, and how the rapid development of artificial intelligence (AI) technology affects green technology innovation (GTI) has received a great deal of attention in the field of economics. Therefore, based on China's inter-provincial panel data from 2006 to 2019, the system GMM, dynamic panel threshold model, and quantile regression model were constructed to examine various influences of AI development on GTI under different environmental regulation intensity, research and development (R&D) investment, and institutional environmental threshold conditions. The findings presented that AI development significantly contributes to GTI and GTFP, with an impact coefficient of 0.0122 and 0.0084, and this influence is mainly reflected in the western region of China and is more obvious in the 2006-2012 period. AI development mainly enhances green technological efficiency, and it has dampening effects on green technological progress during the period 2013-2019. Additionally, there are non-linear threshold effects in the relationship between the level of AI development and GTI when environmental regulatory intensity, R&D investment, and institutional environment are in different level intervals. AI development will boost GTI only when the intensity of environmental regulation and institutional environment is above a certain threshold value. However, the AI development represented by industrial robot applications still has no obvious effect on GTI even when the R&D investment exceeds a certain threshold. Furthermore, the growth effect of AI development on GTI indicates a decreasing nonlinear pattern as the GTI's quantile rises under the condition that R&D investment and institutional environment intensity cross the threshold, while this growth effect increases gradually with the rise of GTI's quantile when the environmental regulation is above the threshold.


Assuntos
Inteligência Artificial , Invenções , Tecnologia , Desenvolvimento Econômico , China , Carbono
14.
J Plankton Res ; 45(1): 180-204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36751483

RESUMO

Following the passage of a tropical cyclone (TC) the changes in temperature, salinity, nutrient concentration, water clarity, pigments and phytoplankton taxa were assessed at 42 stations from eight sites ranging from the open ocean, through the coastal zone and into estuaries. The impacts of the TC were estimated relative to the long-term average (LTA) conditions as well as before and after the TC. Over all sites the most consistent environmental impacts associated with TCs were an average 41% increase in turbidity, a 13% decline in salinity and a 2% decline in temperature relative to the LTA. In the open ocean, the nutrient concentrations, cyanobacteria and picoeukaryote abundances increased at depths between 100 and 150 m for up to 3 months following a TC. While at the riverine end of coastal estuaries, the predominate short-term response was a strong decline in salinity and phytoplankton suggesting these impacts were initially dominated by advection. The more intermediate coastal water-bodies generally experienced declines in salinity, significant reductions in water clarity, plus significant increases in nutrient concentrations and phytoplankton abundance. These intermediate waters typically developed dinoflagellate, diatom or cryptophyte blooms that elevated phytoplankton biomass for 1-3 months following a TC.

15.
Biochem Pharmacol ; 211: 115535, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019190

RESUMO

High-efficiency and low-toxic antimicrobial peptides (AMPs) are supposed to be the future candidates to solve the increasingly prominent problems of Candida albicans infection and drug resistance. Generally, introduction of hydrophobic moieties on AMPs resulted in analogues with remarkably increased activity against pathogens. CGA-N9, an antifungal peptide found in our lab, is a Candida-selective antimicrobial peptide capable of preferentially killing Candida spp. relative to benign microorganisms with low toxicities. We speculate that fatty acid modification could improve the anti-Candida activity of CGA-N9. In the present investigation, a set of CGA-N9 analogues with fatty acid conjugations at N-terminus were obtained. The biological activities of CGA-N9 analogues were determined. The results showed that the n-octanoic acid conjugation of CGA-N9 (CGA-N9-C8) was the optimal CGA-N9 analogue with the highest anti-Candida activity and biosafety; exhibited the strongest biofilm inhibition activity and biofilm eradication ability; and the highest stability against protease hydrolysis in serum. Furthermore, CGA-N9-C8 is less prone to develop resistance for C. albicans in reference with fluconazole; CGA-N9-C8 also exhibited Candidacidal activity to the planktonic cells and the persister cells of C. albicans; reduced C. albicans susceptibility in a systemic candidiasis mouse model. In conclusion, fatty acid modification is an effective method to enhance the antimicrobial activity of CGA-N9, and CGA-N9-C8 is a promising candidate to defend C. albicans infection and resolve C. albicans drug resistance.


Assuntos
Peptídeos Antimicrobianos , Candida albicans , Animais , Camundongos , Ácidos Graxos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Antifúngicos/química , Cromogranina A/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana
16.
Microbiol Spectr ; : e0416922, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36815795

RESUMO

Mount Xianbei is one of the largest shallow seamounts located in the middle of the South China Sea (SCS), which might play a role in shaping the biodiversity of surrounding continental coastal waters, particularly the diversity of phytoplankton species causing frequent harmful algal blooms (HABs) in northern SCS. However, the diversity, composition, and distribution of phytoplankton species in the seamount regions of Xianbei remain largely unexplored. In this study, samples around and outside the seamount regions were collected during a late summer cruise of 2021 to test whether seamounts play a role in HAB species propagation. In total, we identified 19 HAB species across all samples using the ASV-based DNA metabarcoding approach, 6 of which had not been reported previously in the SCS, suggesting a diverse HAB species in the SCS. Specifically, 16 HAB species were found in the seamount region of Xianbei, and 5 of them were also found in the coastal waters, indicating a close connection between seamount and coastal waters. This study was the first attempt to explore HAB species' spatial diversity and vertical distribution in the seamount region of Xianbei at single-nucleotide resolution, which provides a novel explanation for the coastal HAB occurrence in the northern SCS. IMPORTANCE There are a number of seamounts under the water of the South China Sea (SCS). The seamounts might play a role in shaping the biodiversity of surrounding continental coastal waters. However, there is no direct evidence revealing the relationship of the biodiversity of phytoplankton between seamounts and coastal waters in the SCS, especially those species having the potential to form harmful algal blooms (HABs). Some HAB species might proliferate in certain geographic locations, while others may be broadly distributed across oceanic provinces. In this study, we provided a detailed analysis of phytoplankton composition and molecular detection of HAB species from seamount to coastal waters in the SCS, which suggested a strong interaction in the HAB species between the two areas. This finding provides new insights into the diversity and distribution of HABs in seamounts and their role in shaping the composition and the occurrence of HABs in coastal water.

17.
Math Biosci Eng ; 19(6): 5409-5427, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35603362

RESUMO

Marine biology carbon sinks function is vital pathway to earned carbon neutrality object. Algae and shellfish can capture CO2 from atmosphere reducing CO2 concentration. Therefore, algae and shellfish carbon sink capability investigate and forecast are important problem. The study forecast algae and shellfish carbon sinks capability trend base on 9 China coastal provinces. Fractional order accumulation grey model (FGM) is employed to forecast algae and shellfish carbon sinks capability. The result showed algae and shellfish have huge carbon sinks capability. North coastal provinces algae and shellfish carbon sinks capability trend smoothness. South and east coastal provinces carbon sinks capability trend changed drastically. The research advised coastal provinces defend algae and shellfish population, expand carbon sink capability. Algae and shellfish carbon sink resource will promote environment sustainable develop.


Assuntos
Dióxido de Carbono , Sequestro de Carbono , Carbono , Plantas , Frutos do Mar
18.
Artigo em Inglês | MEDLINE | ID: mdl-35565083

RESUMO

Green development is an effective way to reconcile the main contradictions between resources, environment, and regional development. Green total factor productivity (GTFP) is an important index to measure green development; an undesirable output-oriented SBM-DEA model and GML model can be used to calculate GTFP. China's 30 provinces (municipalities and autonomous regions) are divided into three groups: eastern, central, and western. The common frontier function and group frontier function are established, respectively, to deeply explore the temporal and spatial evolution characteristics and center of gravity shift of inter-provincial green total factor productivity (GTFP) in China, and test the convergence under group frontier, to compare the convergence problems under different regions. This study aims to point out the differences in economic growth in different regions of China, foster regional coordination and orderly progress, promote China's green development process, and improve the high-quality economic development level. According to the results, the efficiency of green development is more reasonable under the frontier groups. The average TGR in the eastern region was 0.993, indicating that it reached 99.3% of the meta-frontier green development efficiency technology. The inter-provincial GTFP in China gradually increased, with an average value of 1.043, which means China's green development and ecological civilization construction have achieved remarkable results and the three regions showed significant differences. Judging from the shift path of the spatial center of gravity, the spatial distribution pattern of inter-provincial GTFP in China tends to be concentrated and stable as a whole. Moreover, σ convergence only exists in the western region, while absolute ß convergence and conditional ß convergence exist in eastern, central, and western regions, indicating that the GTFP of different regions will converge to their stable states over time. The results provide a basis for improving the efficiency of institutional allocation of environmental resources, implementing regional differentiated environmental regulation policies, and increasing the value creation of factor resources, which is of great significance for realizing the high-quality economic development in which resources, environment, and economy are coordinated in China.


Assuntos
Desenvolvimento Econômico , Política Ambiental , China , Eficiência , Tecnologia
19.
Environ Sci Pollut Res Int ; 29(46): 69818-69830, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35578078

RESUMO

Local governments are the dominant players in haze pollution control; furthermore, financial power reconstruction affects the effectiveness of haze control. Government innovation preference achieves win-win results for environmental protection and economic development by increasing innovation support. Therefore, a moderating variable for government innovation preference was added to the fiscal decentralization effect on haze pollution, and their interactive effect on haze pollution was studied. This study was conducted in 30 provincial regions. Thus, the severity of regional haze pollution differs because of temporal heterogeneity and asynchronous development. Furthermore, we analyzed the impact on haze pollution from the perspectives of the temporal and spatial differences in different regions of China. The results indicate that (1) fiscal decentralization increases haze pollution, while government innovation preferences control it. (2) In a local evaluation model with a diversified background, fiscal decentralization restrains haze pollution, and pollution source complexity reduces government innovation preference's control pollution function. The interaction term revealed that government innovation preferences had a significant moderating effect. (3) Fiscal decentralization and government innovation preferences control the heterogeneity of haze pollution in different regions.


Assuntos
Poluição do Ar , Poluição Ambiental , Poluição do Ar/prevenção & controle , China , Conservação dos Recursos Naturais , Desenvolvimento Econômico , Governo Local , Política
20.
Environ Sci Pollut Res Int ; 29(39): 59534-59546, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35386078

RESUMO

Carbon dioxide has a significant impact on global climate change due to its natural greenhouse effect. The objective and credible forecast of carbon emissions is very important for the government to formulate and implement the corresponding emission reduction targets. For controlling the growth of carbon emissions, Chinese government has put forward the low-carbon pilot policy and carbon trading policy. However, the existing grey models cannot measure the impact of policies and their interactions. In order to remedy the defect, a novel grey multivariable model based on dummy variables and their interactions is established. Two kinds of grey multivariable models and back propagation neural network model are chosen as comparison models to highlight that the introduction of dummy variables and their interactions plays an important part in improving the model performance. To verify the effectiveness, these four models are selected to simulate and predict the carbon emissions generated from primary energy consumption in Guangdong Province of China. The empirical results indicate that the mean absolute percentage errors of the novel model are 2.87% and 0.86%, respectively, which is significantly better than these three competing models. Finally, based on the outstanding performance of the novel model, it is chosen to forecast the fluctuating tendency of carbon emissions in the next 5 years.


Assuntos
Dióxido de Carbono , Redes Neurais de Computação , Dióxido de Carbono/análise , China , Mudança Climática , Previsões
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