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1.
Zhongguo Zhen Jiu ; 44(3): 261-265, 2024 Mar 12.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38467499

RESUMO

OBJECTIVES: To observe the clinical effect of the modified painless blistering moxibustion with wheat-grain sized moxa cone on cough variant asthma (CVA) differentiated as pathogenic wind attacking the lung and explore the influences on eosinophil count (EOS) in the peripheral blood and the content of interleukin-4 (IL-4) and tumor necrosis factor-α (TNF-α) in the serum of patients. METHODS: Ninety-two patients with CVA of pathogenic wind attacking the lung were randomly divided into an observation group and a control group, 46 cases in each group. In the observation group, the modified painless blistering moxibustion with wheat-grain sized moxa cone was applied to the unilateral Feishu (BL 13), Gaohuang (BL 43) and Zusanli (ST 36) in each session of treatment, once every 3 days. In the control group, budesonide and formoterol powder inhaler was delivered, 4.5 µg per inhalation, once every half an hour after breakfast and dinner; one more time of inhalation needed if the symptoms were not well controlled, but less than 6 times of inhalation per day. The duration of treatment was 8 weeks in both groups. Separately, before and after treatment, and during the 1-month follow-up after treatment completion, the score of the symptoms of traditional Chinese medicine (TCM) was observed in the two groups; using the lung function detector, the indexes of pulmonary function (forced expiratory volume in one second [FEV1], FEV1/forced vital capacity [FVC] and peak expiratory flow [PEF]) were determined, and the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum were determined before and after treatment; and the clinical effect was compared between the two groups. RESULTS: After treatment and in follow-up, the TCM symptom scores were decreased compared with those before treatment in the two groups (P<0.05), and the score in the observation group was lower than that of the control group in follow-up (P<0.05). After treatment, FEV1, FEV1/FVC and PEF were increased when compared with those before treatment in the two groups (P<0.05), and the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum were reduced (P<0.05); there was no statistical difference in these indexes between the two groups (P>0.05). After treatment, the total effective rate of the observation group was 95.7% (44/46), which was not different statistically in comparison with the control group (93.5% [43/46], P>0.05). In the follow-up, the total effective rate of the observation group was 95.7% (44/46), which was higher than that of the control group (78.3% [36/46], P<0.05). CONCLUSIONS: The modified painless blistering moxibustion with wheat-grain sized moxa cone may ameliorate the symptoms of CVA of pathogenic wind attacking the lung and improve the pulmonary functions, which is probably related to the regulation of the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum, thereby, reducing the inflammatory response.


Assuntos
Variante Tussígena da Asma , Moxibustão , Humanos , Triticum , Interleucina-4 , Fator de Necrose Tumoral alfa , Vento , Pulmão
2.
PLoS One ; 19(3): e0299998, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38470873

RESUMO

Gas fluxes from aquatic ecosystems are a significant component of the carbon cycle. Gas exchange across the air-water interface is regulated by near-surface turbulence and can be controlled by different atmospheric forcing conditions, with wind speed and surface buoyancy flux being the most recognized drivers in empirical studies and modeling approaches. The effect of rainfall on near-surface turbulence has rarely been studied and a consistent relationship between rain rate and near-surface turbulence has not yet been established. In this study, we addressed some limitations still present in the quantitative understanding of the effect of rain rate on near-surface turbulence and on the resulting gas transfer velocity in freshwater. We performed controlled laboratory experiments over a wide range of rain rates (7 to 90 mm h-1) and estimated gas transfer velocities from high-resolution measurements of O2 concentration, while rain-induced turbulence was characterized based on particle image velocimetry. We found that the rain-induced dissipation rates of turbulent kinetic energy declined with depth following a consistent power-law relationship. Both energy dissipation rates and gas transfer velocity increased systematically with the rain rate. The results confirm a causal relationship between rainfall, turbulence, and gas exchange. We propose a power-law relationship between near-surface turbulent dissipation rates and rain rate. In combination with surface renewal theory, we derived a direct relationship between gas transfer velocity and rain rate, which can be used to assess the importance of short-term drivers, such as rain events, on gas dynamics and biogeochemical cycling in aquatic ecosystems.


Assuntos
Ecossistema , Água , Vento , Água Doce , Clima
3.
Mol Cell Proteomics ; 23(3): 100738, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38364992

RESUMO

Wind is one of the most prevalent environmental forces entraining plants to develop various mechano-responses, collectively called thigmomorphogenesis. Largely unknown is how plants transduce these versatile wind force signals downstream to nuclear events and to the development of thigmomorphogenic phenotype or anemotropic response. To identify molecular components at the early steps of the wind force signaling, two mechanical signaling-related phosphoproteins, identified from our previous phosphoproteomic study of Arabidopsis touch response, mitogen-activated protein kinase kinase 1 (MKK1) and 2 (MKK2), were selected for performing in planta TurboID (ID)-based quantitative proximity-labeling (PL) proteomics. This quantitative biotinylproteomics was separately performed on MKK1-ID and MKK2-ID transgenic plants, respectively, using the genetically engineered TurboID biotin ligase expression transgenics as a universal control. This unique PTM proteomics successfully identified 11 and 71 MKK1 and MKK2 putative interactors, respectively. Biotin occupancy ratio (BOR) was found to be an alternative parameter to measure the extent of proximity and specificity between the proximal target proteins and the bait fusion protein. Bioinformatics analysis of these biotinylprotein data also found that TurboID biotin ligase favorably labels the loop region of target proteins. A WInd-Related Kinase 1 (WIRK1), previously known as rapidly accelerated fibrosarcoma (Raf)-like kinase 36 (RAF36), was found to be a putative common interactor for both MKK1 and MKK2 and preferentially interacts with MKK2. Further molecular biology studies of the Arabidopsis RAF36 kinase found that it plays a role in wind regulation of the touch-responsive TCH3 and CML38 gene expression and the phosphorylation of a touch-regulated PATL3 phosphoprotein. Measurement of leaf morphology and shoot gravitropic response of wirk1 (raf36) mutant revealed that the WIRK1 gene is involved in both wind-triggered rosette thigmomorphogenesis and gravitropism of Arabidopsis stems, suggesting that the WIRK1 (RAF36) protein probably functioning upstream of both MKK1 and MKK2 and that it may serve as the crosstalk point among multiple mechano-signal transduction pathways mediating both wind mechano-response and gravitropism.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Gravitropismo , Biotina/metabolismo , Vento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fosfoproteínas/metabolismo , Ligases/metabolismo , Calmodulina/metabolismo
4.
J Thorac Cardiovasc Surg ; 167(1): 271-280.e4, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-36456359

RESUMO

OBJECTIVE: Increasing forces threaten the viability of thoracic surgeon-initiated research, a core component of our academic mission. National Institutes of Health funding is a benchmark of research productivity and innovation. This study examined the current status of National Institutes of Health funding for thoracic surgeons. METHODS: Thoracic surgeon principal investigators on National Institutes of Health-funded grants during June 2010, June 2015, and June 2020 were identified using National Institutes of Health iSearchGrants (version 2.4). American Association of Medical Colleges data were used to identify all surgeons in the United States. Types and total costs of National Institutes of Health-funded grants were compared relative to other surgical specialties. RESULTS: A total of 61 of 4681 (1.3%), 63 of 4484 (1.4%), and 60 of 4497 (1.3%) thoracic surgeons were principal investigators on 79, 76, and 87 National Institutes of Health-funded grants in 2010, 2015, and 2020, respectively; these rates were higher than those for most other surgical specialties (P ≤ .0001). Total National Institutes of Health costs for Thoracic Surgeon-initiated grants increased 57% from 2010 to 2020, outpacing the 33% increase in total National Institutes of Health budget. Numbers and types of grants varied among cardiovascular, transplant, and oncology subgroups. Although the majority of grants and costs were cardiovascular related, increased National Institutes of Health expenditures primarily were due to funding for transplant and oncology grants. Per-capita costs were highest for transplant-related grants during both years. Percentages of R01-to-total costs were constant at 55%. Rates and levels of funding for female versus male thoracic surgeons were comparable. Awards to 5 surgeons accounted for 33% of National Institutes of Health costs for thoracic surgeon principal investigators in 2020; a similar phenomenon was observed for 2010 and 2015. CONCLUSIONS: Long-term structural changes must be implemented to more effectively nurture the next generation of thoracic surgeon scientists.


Assuntos
Pesquisa Biomédica , Cirurgiões , Humanos , Masculino , Feminino , Estados Unidos , Vento , National Institutes of Health (U.S.) , Organização do Financiamento
5.
Sci Rep ; 13(1): 21558, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057437

RESUMO

To explore the influence of wind speed on the quality of tobacco in this study, we employed a heat pump-powered intensive curing barn and a three-stage curing process. By evaluating the influence of fan parameters on the quality of tobacco leaves at different curing stages, the optimal wind speed was determined. After adopting the optimized wind speed process, the degradation of macromolecular substances was faster, the accumulation of aroma substances was delayed to 55 °C, and the accumulation was more complete. Among them, the contents of reducing sugar and total sugar in flue-cured tobacco leaves were 22.25% and 29.2%, respectively, which were lower than those in the control group. The sugar was converted into more aroma substances, and the total amount of neutral aroma substances was 48.82% higher than that of the control group. The content of related aroma substances increased significantly. The content of petroleum ether extract related to aroma substances increased by 0.93% compared with the control group. The macromolecular substances were degraded more fully than the control group, such as the starch content decreased to 1.56%. The results of metabolomics showed that the contents of aldehydes, heterocyclic compounds, alcohols, ketones and esters increased significantly in different degrees after this process. These results show that the optimization of wind speed parameters can significantly improve the baking quality of tobacco leaves. This study provides a reference for the optimization of the flue-cured tobacco baking process.


Assuntos
Temperatura Alta , Vento , Nicotiana , Folhas de Planta , Açúcares , Substâncias Macromoleculares
6.
Genes (Basel) ; 14(10)2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37895302

RESUMO

Metabolism and the immunological state are intimately intertwined, as defense responses are bioenergetically expensive. Metabolic homeostasis is a key requirement for the proper function of immune cell subsets, and the perturbation of the immune-metabolic balance is a recurrent event in many human diseases, including cancer, due to nutrient fluctuation, hypoxia and additional metabolic changes occurring in the tumor microenvironment (TME). Although much remains to be understood in the field of immunometabolism, here, we report the current knowledge on both physiological and cancer-associated metabolic profiles of immune cells, and the main molecular circuits involved in their regulation, highlighting similarities and differences, and emphasizing immune metabolic liabilities that could be exploited in cancer therapy to overcome immune resistance.


Assuntos
Neoplasias , Vento , Humanos , Neoplasias/patologia , Microambiente Tumoral/genética
7.
Mar Pollut Bull ; 194(Pt A): 115270, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37566977

RESUMO

A new 3-D Hybrid Monte Carlo Simulation (MCS) Risk Model is proposed in this study. The wind, wave, current, climate change, and tsunami sub-models of the Three-Dimensional Hydrodynamic Transport and Water Quality Model HYDROTAM-3D are interrelated with MCS, to obtain probability distributions for the simulation of environmental conditions. This is the only model that can incorporate the tsunami, storm, and sea level rise risks in oil exploration projects. The spill risk index (SRI) of 50 blue barrels spilled due to a blowout from the rig/port during fuel supply was circa 1 ton/ship as Tier I with an average annual occurrence probability of 1.0 × 10-6. The discharge of 4000 bbls for 6 h was modeled, resulting in the SRI of 546 metric tons from the riser blowout with SRI = 0.2 per meter, indicating a Tier II risk. The mean arrival time of this spill was found by MCS as 145 min.


Assuntos
Poluição por Petróleo , Poluição por Petróleo/análise , Método de Monte Carlo , Simulação por Computador , Vento , Qualidade da Água
8.
Mar Pollut Bull ; 194(Pt B): 115275, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37451045

RESUMO

We employed GNOME to simulate the oil spill due to the sinking of the tanker "Agia Zoni ΙΙ" in September 2017 in Saronic Gulf. We performed simulations using various combinations of wind and current input, and values of the GNOME parameters, and compared the simulated oil spill trajectories with coastal pollution and satellite data. The best scenario, i.e., the combination that showed the most satisfactory agreement with field data, uses wind data from one of the closest meteorological stations, calculated currents by a hydrodynamic model and default values of the parameters, except for the windage and the refloat half-life whose proposed values are 3-4 % and 6 h, respectively. Neglecting the effect of the wind in the best scenario worsened the agreement. Mass balance results depicted that approximately 47 % of the total 500 tons of the oil spill ended up on the coastline of Attica peninsula and Salamina Island.


Assuntos
Poluição por Petróleo , Poluentes Químicos da Água , Poluição por Petróleo/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Grécia , Vento
9.
Mar Pollut Bull ; 193: 115154, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37429157

RESUMO

Offshore oil spills often result in severe environmental and socio-economic consequences. This work focuses on a busy, yet poorly studied part of NW Europe, the Irish Sea, to assess the impact of future oil spills on the nearby coast. By integrating numerical models and shoreline sensitivity analyses for two confined areas, Liverpool Bay and Milford Haven, this work acknowledges wind direction and speed as principal controls on the movement of oil under winter/storm conditions and in shallow waters. Ocean currents play a secondary role, but are significant in deeper waters and in low-wind summer conditions. The temporal elements used in the modelling thus stress that when the spill occurs is just as important as where. As a corollary, the fate of spilled oil is determined in this work for distinct scenarios and types. Response strategies are recommended to minimise the impact of future spills on coastal populations.


Assuntos
Poluição por Petróleo , Poluição por Petróleo/análise , Modelos Teóricos , Vento , Estações do Ano , Europa (Continente) , Monitoramento Ambiental
10.
Phys Rev E ; 107(5-2): 055212, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37329056

RESUMO

A recent numerical treatment of data obtained by the Parker Solar Probe spacecraft describes the electron concentration in solar wind as a function of the heliocentric distance based on a Kappa distribution with spectral index κ=5. In this work, we derive and, subsequently, solve an entirely different class of nonlinear partial differential equations describing the one-dimensional diffusion of a suprathermal gas. The theory is applied to describe the aforementioned data and we find a spectral index κ≳1.5 providing the widely acknowledged identification of Kappa electrons in solar wind. We also find that suprathermal effects increase the length scale of classical diffusion by one order of magnitude. Such a result does not depend on the microscopic details of the diffusion coefficient since our theory is based on a macroscopic formulation. Forthcoming extensions of our theory by including magnetic fields and relating our formulation to nonextensive statistics are briefly addressed.


Assuntos
Elétrons , Vento , Difusão
11.
Environ Res ; 233: 116472, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37348631

RESUMO

Inland waters are significant sources of atmospheric greenhouse gas (GHG) emissions. The thin boundary layer (TBL) model is often employed as a means of estimating GHG diffusion in inland waters based on gas transfer velocity (k) at the air-water interface, with k being subject to regulation by near-surface turbulence that is primarily driven by wind speed in many cases. This wind speed-based estimation of k (wind-k), however, can introduce substantial uncertainty for turbulent waterways where wind speed does not accurately represent overall turbulence. In this study, GHG diffusion in the Beijing-Hangzhou Grand Canal (China), the first and longest man-made canal in the world, was estimated using the TBL model, revealing that this model substantially underestimated GHG diffusion when relying on wind-k. Strikingly, the carbon dioxide, methane, and nitrous oxide diffusions were respectively underestimated by 159%, 162%, and 124% when using this model. These findings are significant for developing more reliable approaches to evaluate GHG emissions from inland waterways.


Assuntos
Gases de Efeito Estufa , Humanos , Dióxido de Carbono/análise , Vento , Metano/análise , China , Óxido Nitroso , Efeito Estufa
12.
Environ Sci Pollut Res Int ; 30(29): 73899-73912, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37199841

RESUMO

Based on the Jilin Songyuan gas pipeline accident, FLACS software was used to numerically simulate its leakage and explosion process in order to study the change law of the equivalent gas cloud volume of gas leakage diffusion under various influencing factors. The simulation results were compared and analyzed with the accident investigation report in order to ensure the accuracy of the simulation results. On this premise, the three primary influencing factors-the obstacle distribution technique, the ambient wind speed magnitude, and the ambient temperature-are varied in order to study the equivalent gas cloud volume variation features of the leaking gas cloud. The findings indicate a positive association between the maximum equivalent gas cloud volume of the leaking gas cloud and the density of the obstacle distribution. There is a positive correlation between ambient wind speed and the equivalent gas cloud volume when the ambient wind speed is less than 5.0 m/s, and a negative correlation between ambient wind speed and the equivalent gas cloud volume when the ambient wind speed is greater than or equal to 5.0 m/s. A drop in Q8 is proportionately increased by around 5% for every 10 °C increase in ambient temperature when the temperature is below room temperature. There is a positive association between ambient temperature and the equivalent gas cloud volume Q8. When the temperature is higher than room temperature, the drop in Q8 is correspondingly increased by about 3% for every 10 °C increase in ambient temperature.


Assuntos
Explosões , Vento , Temperatura , Simulação por Computador , Software
13.
Sci Total Environ ; 889: 164062, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37207767

RESUMO

Dust storms are a significant concern because of their adverse effects on ambient air quality and human health. To investigate the evolution of dust storms during long-distance transport and its impacts on air quality and human health risks in cities along the transport pathway, we monitored the major fraction of dust (i.e., particle-bound elements) online in four cities in northern China during March 2021. Three dust events originating from the Gobi Desert of North China and Mongolia and the Taklimakan Desert of Northwest China were captured. We investigated the source regions of dust storms using daily multi-sensor absorbing aerosol index products, backward trajectories, and specific element ratios, identified and quantified sources of particle-bound elements using Positive Matrix Factorization model, and calculated the carcinogenic and non-carcinogenic risks of elements using a health risk assessment model. Our results indicated that under the influence of dust storms, mass concentrations of crustal elements increased up to dozens of times in cities near the dust source and up to ten times in cities farther from the source. In contrast, anthropogenic elements increased less or even decreased, depending on the relative contributions of the increase caused by accumulation of dust itself and entrainment along the transport path and the decrease caused by dilution of high wind speeds. Si/Fe ratio was found to be a valuable indicator for characterizing the attenuation of the amount of dust along its transport pathways, especially for the case originated from northern source regions. This study highlights the significant role of source regions, intensity and attenuation rates of dust storms, and wind speeds in determining the increased levels of element concentrations during dust storms and its associated impacts on downwind areas. Furthermore, non-carcinogenic risks of particle-bound elements increased at all sites during dust events, emphasizing the importance of personal exposure protection during dust storms.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Humanos , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poeira/análise , Vento , China , Cidades , Material Particulado/análise
14.
Arch Environ Contam Toxicol ; 84(3): 347-367, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37039904

RESUMO

In the present study, the researchers used an integrated approach composed of response surface analysis (RSM) and MPACT model to predict fatality rates caused by benzene emitted from floating-roof tanks. RSM scenarios were configured in Expert Design (version 7.0) software using the central composite design (CCD) method and five variables of wind speed, relative humidity, atmospheric temperature, failure diameter, and emission height were considered. Continuous Pasquill-Gifford Gaussian model was used to estimate the results of the RSM scenarios. The response values were considered for exposure concentrations above 50 ppm (slight damages), 150 ppm (moderate damage), and 1000 ppm (high damage). The analysis of individual and social risks for each scenario was done using the MPACT model in SAFETI program (version 8.22) by providing two variables of population characteristics and the frequency of tank wall failure. The results showed that atmospheric temperature, wind speed, failure diameter, and emission height have positive effects on the dispersion of the cloud of toxic benzene vapor with a concentration of 1000 ppm. Intolerable individual risk distances were estimated to be lower for indoor environments than for outdoor. Maximum distances of intolerable individual risks for the worst-case scenarios were estimated up to 2500 m from the emission point, which resulted from exposure to a concentration of 1000-ppm benzene. Results regarding the estimation of social risks showed that over 1600 fatalities should be expected under the worst-case scenarios. The three factors of high temperature, low wind speed, and low emission height play a major role in the occurrence of scenarios with the highest fatalities. High wind speed and high emission height were the most important factors in most scenarios with zero fatalities rate. Generally, the findings of this study show the necessity to provide an emergency response plan in the studied industry in both autumn and winter due to low wind speed. However, the coupling of the developed statistical models based on regional meteorological conditions with the MPACT model can help researchers to design an emergency response plan to deal with leakage incidents in petrochemical industries.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Benzeno/análise , Vento , Estações do Ano
15.
Nat Commun ; 14(1): 1303, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894593

RESUMO

The Southern Ocean is a major sink of anthropogenic CO2 and an important foraging area for top trophic level consumers. However, iron limitation sets an upper limit to primary productivity. Here we report on a considerably dense late summer phytoplankton bloom spanning 9000 km2 in the open ocean of the eastern Weddell Gyre. Over its 2.5 months duration, the bloom accumulated up to 20 g C m-2 of organic matter, which is unusually high for Southern Ocean open waters. We show that, over 1997-2019, this open ocean bloom was likely driven by anomalies in easterly winds that push sea ice southwards and favor the upwelling of Warm Deep Water enriched in hydrothermal iron and, possibly, other iron sources. This recurring open ocean bloom likely facilitates enhanced carbon export and sustains high standing stocks of Antarctic krill, supporting feeding hot spots for marine birds and baleen whales.


Assuntos
Ecossistema , Cadeia Alimentar , Vento , Ferro , Fitoplâncton , Regiões Antárticas , Oceanos e Mares
16.
Environ Sci Pollut Res Int ; 30(19): 54742-54752, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36881233

RESUMO

This study researches the impact of terrain factors on chlorine gas diffusion processes based on SLAB model. Simulating the law of wind speed changing with altitude by calculating the real-time speed with vertical height combing actual terrain data, and integrating the influence of terrain on wind speed by using Reynolds Average Navier-Stokes (RANS) algorithm, K-turbulence model, and standard wall functions, then plotting the gas diffusion range in the map with terrain data according to the Gaussian-Cruger projection algorithm and dividing the hazardous areas according to the public exposure guidelines (PEG). The accidental chlorine gas releases near Lishan Mountain, Xi'an City, were simulated by the improved SLAB model. The results show that there are obvious differences analyzing contrastively the endpoint distance and area of chlorine gas dispersion under real terrain condition and ideal condition at different times; it can be found that the endpoint distance of the real terrain conditions is 1.34 km shorter than that of the ideal conditions at 300 s with terrain factors, and also the thermal area is 3,768,026m2 less than that of the ideal conditions. In addition, it can predict the specific number of casualties within different levels of harm at 2 min after chlorine gas dispersion, and casualties are constantly changing over time. The fusion of terrain factors can be used to optimize the SLAB model, which is expected to provide an important reference for effective rescue.


Assuntos
Poluentes Atmosféricos , Cloro , Poluentes Atmosféricos/análise , Modelos Teóricos , Simulação por Computador , Vento
17.
Ecology ; 104(6): e4039, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36960918

RESUMO

Following a disturbance, dispersal shapes community composition as well as ecosystem structure and function. For fungi, dispersal is often wind or mammal facilitated, but it is unclear whether these pathways are complementary or redundant in the taxa they disperse and the ecosystem functions they provide. Here, we compare the diversity and morphology of fungi dispersed by wind and three rodent species in recently harvested forests using a combination of microscopy and Illumina sequencing. We demonstrate that fungal communities dispersed by wind and small mammals differ in richness and composition. Most wind-dispersed fungi are wood saprotrophs, litter saprotrophs, and plant pathogens, whereas fungi dispersed in mammal scat are primarily mycorrhizal, soil saprotrophs, and unspecified saprotrophs. We note substantial dispersal of truffles and agaricoid mushrooms by small mammals, and dispersal of agaricoid mushrooms, crusts, and polypores by wind. In addition, we find mammal-dispersed spores are larger than wind-dispersed spores. Our findings suggest that wind- and small-mammal-facilitated dispersal are complementary processes and highlight the role of small mammals in dispersing mycorrhizal fungi, particularly following disturbances such as timber harvest.


Assuntos
Ecossistema , Micorrizas , Animais , Vento , Florestas , Mamíferos , Roedores , Microbiologia do Solo , Fungos , Solo , Esporos Fúngicos
18.
Environ Pollut ; 323: 121210, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36773687

RESUMO

Trees grown in streets impact air quality by influencing ventilation (aerodynamic effects), pollutant deposition (dry deposition on vegetation surfaces), and atmospheric chemistry (emissions of biogenic volatile organic compounds, BVOCs). To qualitatively evaluate the impact of trees on pollutant concentrations and assist decision-making for the greening of cities, 2-D simulations on a street in greater Paris were performed using a computational fluid dynamics tool coupled to a gaseous chemistry module. Globally, the presence of trees has a negative effect on the traffic-emitted pollutant concentrations, such as NO2 and organic condensables, particularly on the leeward side of a street. When not under low wind conditions, the impact of BVOC emissions on the formation of most condensables within the street was low owing to the short characteristic time of dispersion compared with the atmospheric chemistry. However, autoxidation of BVOC quickly forms some extremely-low volatile organic compounds, potentially leading to the formation of ultra-fine particles. Planting trees in streets with traffic is only effective in mitigating the concentration of some oxidants such as ozone (O3), which has low levels in cities regardless of this, and hydroxyl radical (OH), which may slightly lower the rate of oxidation reactions and the formation of secondary species in the street.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Árvores , Compostos Orgânicos Voláteis/análise , Poluição do Ar/análise , Vento , Cidades , Emissões de Veículos/análise , Modelos Teóricos
19.
Sci Total Environ ; 870: 161987, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36740072

RESUMO

Polycyclic Aromatic Hydrocarbons (PAHs) compounds are ubiquitous in ambient air due to their persistence, carcinogenicity, and mutagenicity. Gangtok being one of the cleanest cities in India located in Eastern Himalayan region, witnesses high developmental activities with enhanced urbanization affecting the ambient air quality. The present study aims to measure PM2.5 and PAHs in the ambient atmosphere of the Sikkim Himalaya to understand the influence of natural and anthropogenic activities on aerosol loading and their chemical characteristics. The PM2.5 samples were collected and analysed for the duration from Jan 2020 to Feb 2021.The seasonal mean concentrations of PM2.5 and PAHs were observed to be high during autumn and low during summer season. Overall, the annual mean concentration of PM2.5 was found higher than the prescribed limit of World Health Organization and National Ambient Air Quality Standards. The concentration of the 16 individual PAHs were found to be highest during autumn season (55.26 ± 37.15 ng/m3). Among the different PAHs, the annual mean concentration of fluorene (3.29 ± 4.07 ng/m3) and naphthalene (1.15 ± 3.76 ng/m3) were found to be the highest and lowest, respectively. The Molecular Diagnostic Ratio (MDR) test reveals higher contribution from heavy traffic activities throughout the winter and autumn seasons. The other possible sources identified over the region are fossil fuel combustion, and biomass burning. The multivariate statistical analysis (Multifactor Principal Component Analysis) also indicates a strong association between PM2.5 /PAHs and meteorological variables across the region in different seasons. The precipitation and wind pattern during the study period suggests that major contribution of the PM2.5 and PAHs were from local sources, with minimal contribution from long-range transport. The findings are important for comprehending the trends of PAH accumulation over a high-altitude urban area, and for developing sustainable air quality control methods in the Himalayan region.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Siquim , Altitude , Monitoramento Ambiental/métodos , Atmosfera/química , Estações do Ano , Vento , Aerossóis/análise , China
20.
Huan Jing Ke Xue ; 44(1): 104-117, 2023 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-36635800

RESUMO

Accurate meteorological fields and applicable air quality models are important ways to optimize air pollution simulations. To improve the accuracy of winter air pollution models in the Sichuan basin, we conducted a meteorological field simulation using 25 sets of parameterized scheme combinations in the Weather Research and Forecasting (WRF) Model. Based on the optimal parameters, the air pollution levels were simulated using AERMOD and CALPUFF models in a local large steel plant, and the data were verified by comparing the data from four National Ambient Air Monitoring Stations (NAAMS). The results indicated that the WRF model parameters had substantial effects on the simulation of the ground wind field, high-altitude wind field, and ground humidity field. In contrast, the parameters had no significant effect on the simulation of the ground temperature field, high-altitude temperature field, and high-altitude humidity field. The combination of the SLAB land surface process scheme and Dudhia shortwave radiation scheme with four boundary layer schemes, namely YSU, ACM2, BouLac, and MRF, could well-simulate the trends of winter surface wind, temperature, and humidity fields in Sichuan basin. The simulation results were analyzed by combining the statistical parameters of high-altitude wind, temperature, and humidity. The group 1 parameter scheme was applicable to simulate the meteorological field of Dazhou. Group 13 and Group 17 parameters were applicable to simulate the meteorological fields in Chengdu during the day and night, respectively. The correlation between CALPUFF simulation and monitoring value was better than that for AERMOD. CALPUFF was more accurate than AERMOD when referring to the monitoring data from NAAMS No.3. In addition, the simulation quality of CALPUFF was slightly better than that of AERMOD with reference to data from NAAMS No.2. Using air pollutant monitoring data from NAAMS as a reference, the simulated results of CALPUFF on NOx and PM10 were improved compared to AERMOD at all four stations. Data from the Q-Q diagram indicated that the simulated results of CALPUFF on SO2, NOx, and PM10 were closer to the monitored values compared to those of AERMOD.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Tempo (Meteorologia) , Poluição do Ar/prevenção & controle , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Vento , Estações do Ano , Monitoramento Ambiental/métodos , Material Particulado/análise
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