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BACKGROUND: Angina is a crucial risk signal for cardiovascular disease. However, few studies have evaluated the effects of ambient air pollution exposure on angina. OBJECTIVE: We aimed to explore the short-term effects of air pollution on hospitalization for angina and its lag effects. METHODS: We collected data on air pollutant concentrations and angina hospitalizations from 2013 to 2020. Distributed lag nonlinear model (DLNM) was used to evaluate the short-term effects of air pollutants on angina hospitalization under different lag structures. Stratified analysis by sex, age and season was obtained. RESULTS: A total of 39,110 cases of angina hospitalization were included in the study. The results showed a significant positive correlation between PM2.5, SO2, NO2, and CO and angina hospitalization. Their maximum harmful effects were observed at lag0-7 (RR = 1.042; 95% CI: 1.017, 1.068), lag0-3 (RR = 1.067; 95% CI: 1.005, 1.133), lag0-6 (RR = 1.078; 95% CI: 1.041, 1.117), and lag0-6 (RR = 1.244; 95% CI: 1.109, 1.397), respectively. PM10 did not have an overall risk effect on angina hospitalization, but it did have a risk effect on women and the elderly. O3 was significantly negatively correlated with angina hospitalization, with the most pronounced effect observed at lag0-6 (RR = 0.960; 95% CI: 0.940, 0.982). Stratified analysis results showed that women and the elderly were more susceptible to pollutants, and the adverse effects of pollutants were stronger in the cold season. CONCLUSION: Short-term exposure to PM2.5, SO2, NO2, and CO increases the risk of hospitalization for angina.
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Poluentes Atmosféricos , Angina Pectoris , Hospitalização , Humanos , Feminino , Hospitalização/estatística & dados numéricos , Masculino , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Pessoa de Meia-Idade , Idoso , Angina Pectoris/epidemiologia , Poluição do Ar/efeitos adversos , Material Particulado/efeitos adversos , Material Particulado/análise , Adulto , Exposição Ambiental/efeitos adversos , China/epidemiologia , Estações do AnoRESUMO
Coronary heart disease (CHD) is one of the most serious public health problems. However, few studies have focused on the effects of exposure to particulate matter and gaseous air pollutants on CHD. This study aimed to explore the relationship between air pollutants and the number of hospitalized patients with CHD in Lanzhou, and we collected daily data on the number of hospitalized patients with CHD, daily air pollutants, and meteorological factors from 2013 to 2020. A distributed lag nonlinear model (DLNM) combined with a quasi-Poisson regression model was applied to evaluate the relationship between air pollutants and the number of hospitalized patients with CHD. The results indicated that the hysteresis effect of all pollutants except O38h reached its maximum at lag3, and the relative risk of coronary heart disease admission was 1.0014 (95%CI: 1.0004, 1.0023), 1.0003 (95%CI: 1.0000, 1.0006), 1.0020 (95%CI: 1.0004, 1.0035), and 1.0053 (95%CI: 1.0026, 1.0080) when PM2.5, PM10, NO2, and SO2 concentrations were increased by 10 µg/m3, respectively. Each 1 mg/m3 increase in CO concentration was associated with a relative risk of coronary heart disease; hospitalization risk was 1.1076 (95%CI: 1.0530, 1.1650). We observed a relative risk of 0.9991 (95%CI: 0.9986, 0.9999) for each 10 µg/m3 increase in O38h for coronary heart disease admission at lag1. Women and elderly were more susceptible to the impact of air pollution, and the impact was greater during cold seasons. Our results indicate that air pollution increased the risk of hospitalization for CHD in a short term. The research findings can provide strategic insights into the impact of current and future air pollution on CHD.
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Poluentes Atmosféricos , Poluição do Ar , Doença das Coronárias , Humanos , Feminino , Idoso , Fatores de Tempo , Poluição do Ar/efeitos adversos , Poluentes Atmosféricos/efeitos adversos , Hospitalização , Doença das Coronárias/epidemiologia , China/epidemiologia , Exposição Ambiental/efeitos adversosRESUMO
BACKGROUND Depression is a major mood disorder. Some patients have been reported to improve following acupuncture. This study aimed to investigate the effects of acupuncture on behaviors associated with depression in the chronic unpredictable mild stress (CUMS) rat model. The expression of signaling pathway components of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) in the rat hippocampus and plasma were also measured. MATERIAL AND METHODS Male Sprague-Dawley rats (N=40) were divided into the control group (N=10), the model group (N=10), the acupuncture group (N=10), and the non-acupuncture group (N=10). The rat model was established by orphaning combined with chronic unpredictable mild stress (CUMS) for six weeks. The acupuncture group was given 21 days of treatment using acupoints (AP) or non-acupoints (NP). Rat behaviors associated with depression were tested using the sucrose preference test (SPT), the open field test (OFT), and the elevated plus maze (EPM) test. Enzyme-linked immunoassay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) were used to detect the expression of inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS), and the N-methyl-D-aspartate (NMDA) receptor subunits, NR1, NR2A, and NR2B in the rat plasma and hippocampus. RESULTS Acupuncture reversed the behaviors associated with depression in the CUMS rat model and reduced the expression of components of the NO and cGMP pathway in the rat hippocampus and plasma. CONCLUSIONS In the CUMS rat model, treatment with acupuncture reduced behaviors associated with depression, and these effects were associated with changes in the NO and cGMP signaling pathway.
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GMP Cíclico/metabolismo , Óxido Nítrico/metabolismo , Estresse Psicológico/terapia , Pontos de Acupuntura , Terapia por Acupuntura/métodos , Animais , Antidepressivos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Transtorno Depressivo Maior/tratamento farmacológico , Modelos Animais de Doenças , Guanosina Monofosfato , Hipocampo/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico/metabolismoRESUMO
Straw incorporation with nitrogen (N) fertilization is crucial for enhancing soil fertility and minimizing negative environmental impacts by altering the magnitude and direction of soil N transformation processes. However, the response of soil N transformations to long-term carbon (C) and N inputs, and their primary driving factors, remain poorly understood. Thus, a 15N tracing study was conducted to investigate the effects of straw incorporation (AS) and straw removal (NS) with N levels of 0, 150 and 250 kg N ha-1 per season (N0, N150 and N250) on gross N transformation rates in the North China Plain after 6-year trial. Results indicated that at N0, AS significantly increased soil microbial immobilization of nitrate (NO3--N, INO3) and autotrophic nitrification rates (ONH4) compared to NS. With N fertilization, AS increased gross N immobilization (Itotal), ammonium-N immobilization (NH4+-N, INH4), net NH4+-N immobilization (InetNH4) and net NH4+-N absorption rates (AnetNH4). Specifically, at N150, AS significantly increased recalcitrant organic N mineralization rate (MNrec), while significantly reducing ONH4, labile organic N mineralization (MNlab), and gross N mineralization rates (Mtotal). At N250, AnetNH4, MNlab, MNrec and ONH4 under AS were significantly higher than under NS. Nitrogen application significantly increased ONH4, Itotal and INO3 under two straw management practices, and enhanced INH4 and InetNH4 under AS. Compared to N250, N150 significantly increased INH4 and InetNH4 under AS, while decreasing Mtotal. Opposite results were observed under NS. Meanwhile, NO3--N and dissolved organic carbon (DOC) were master factors controlling immobilization, total nitrogen (TN), hydrolysable NH4+-N (HNN) and stable organic N significantly affected AnetNH4, while labile organic N were the key environmental factors affecting MNrec, all of which positively influenced the rates of assimilation, mineralization and clay mineral adsorption. Overall, this study provides new insights into reducing N fertilization under straw incorporation by quantifying soil N transformation processes.
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Agricultura , Fertilizantes , Nitrogênio , Solo , China , Nitrogênio/análise , Solo/química , Agricultura/métodos , Nitrificação , Microbiologia do Solo , Monitoramento Ambiental , Água Subterrânea/químicaRESUMO
Background: Increasing research has implicated the possible effect of gut microbiota (GM) on the prognosis of ischemic stroke (IS). However, the precise causal relationship between GM and functional outcomes after IS remains unestablished. Methods: Data on 211 GM taxa from the MiBioGen consortium and data on prognosis of IS from the Genetics of Ischemic Stroke Functional Outcome (GISCOME) network were utilized as summary-level data of exposure and outcome. Four kinds of Mendelian randomization (MR) methods were carried out to ascertain the causal effect of GM on functional outcomes following IS. A reverse MR analysis was performed on the positive taxa identified in the forward MR analysis to determine the direction of causation. In addition, we conducted a comparative MR analysis without adjusting the baseline National Institute of Health Stroke Scale (NIHSS) of post-stroke functional outcomes to enhance confidence of the results obtained in the main analysis. Results: Four taxa were identified to be related to stroke prognosis in both main and comparative analyses. Specifically, genus Ruminococcaceae UCG005 and the Eubacterium oxidoreducens group showed significantly negative effects on stroke prognosis, while the genus Lachnospiraceae NK4A136 group and Lachnospiraceae UCG004 showed protective effects against stroke prognosis. The reverse MR analysis did not support a causal role of stroke prognosis in GM. No evidence of heterogeneity, horizontal pleiotropy, and outliers was found. Conclusion: This MR study provided evidence that genetically predicted GM had a causal link with post-stroke outcomes. Specific gut microbiota taxa associated with IS prognosis were identified, which may be helpful to clarify the pathogenesis of ischemic stroke and making treatment strategies.
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Nitrogen dioxide (NO2) represents a deleterious effect on acute myocardial infarction (AMI), but few relevant studies have been conducted in China. We aim to evaluate the acute effects of NO2 exposure on hospitalization for AMI in Lanzhou, China. In this study, we applied a distributional lag nonlinear model (DLNM) to assess the association between NO2 exposure and AMI hospitalization. We explored the sensitivity of various groups through stratified analysis by gender, age, and season. The daily average concentration of NO2 is 47.50 ± 17.38 µg/m3. We observed a significant exposure-response relationship between NO2 concentration and AMI hospitalization. The single pollutant model analysis shows that NO2 is positively correlated with AMI hospitalization at lag1, lag01, lag02, and lag03. The greatest lag effect estimate occurs at lag01, where a 10 µg/m3 increase in NO2 concentrations is significantly associated with a relative risk (RR) of hospitalization due to AMI of 1.027 [95% confidence interval (CI): 1.013, 1.042]. The results of the stratified analysis by gender, age, and season indicate that males, those aged ≥65 years, and the cold season are more sensitive to the deleterious effects caused by NO2 exposure. Short-term exposure to NO2 can enhance the risk of AMI hospitalization in urban Lanzhou.Implications: Exposure to particulate matter can lead to an increased incidence of AMI. Our study once again shows that NO2 exposure increases the risk of AMI hospital admission. AMI is a common and expensive fatal condition. Reducing NO2 exposure will benefit cardiovascular health and save on healthcare costs.
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Poluentes Atmosféricos , Hospitalização , Infarto do Miocárdio , Dióxido de Nitrogênio , China/epidemiologia , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/induzido quimicamente , Humanos , Masculino , Dióxido de Nitrogênio/análise , Feminino , Idoso , Pessoa de Meia-Idade , Hospitalização/estatística & dados numéricos , Poluentes Atmosféricos/análise , Estações do Ano , Exposição Ambiental/efeitos adversos , Poluição do Ar/efeitos adversos , Poluição do Ar/análiseRESUMO
Extensive evidence has shown that air pollution increases the risk of cardiovascular disease (CVD) admissions. We aimed to explore the short-term effect of air pollution on CVD admissions in Lanzhou residents and their lag effects. Meteorological data, air pollution data, and a total of 309,561 daily hospitalizations for CVD among urban residents in Lanzhou were collected from 2013 to 2020. Distributed lag non-linear model was used to analyze the relationship between air pollutants and CVD admissions, stratified by gender, age, and season. PM2.5, NO2, and CO have the strongest harmful effects at lag03, while SO2 at lag3. The relative risks of CVD admissions were 1.0013(95% CI: 1.0003, 1.0023), 1.0032(95% CI: 1.0008, 1.0056), and 1.0040(95% CI: 1.0024, 1.0057) when PM2.5, SO2, and NO2 concentrations were increased by 10 µg/m³, respectively. Each 1 mg/m3 increase in CO concentration was associated with a relative risk of cardiovascular hospitalization of risk was 1.0909(95% CI: 1.0367, 1.1479). We observed a relative risk of 0.9981(95% CI: 0.9972, 0.9991) for each 10 µg/m³ increase in O3 for CVD admissions at lag06. We found a significant lag effects of air pollutants on CVD admissions. NO2 and CO pose a greater risk of hospitalization for women, while PM2.5 and SO2 have a greater impact on men. PM2.5, NO2, and CO have a greater impact on CVD admissions in individuals aged <65 years, whereas SO2 affects those aged ≥65 years. Our research indicates a possible short-term impact of air pollution on CVD. Local public health and environmental policies should take these preliminary findings into account.
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BACKGROUND: Depression is associated with lowered mood, anxiety, anhedonia, cognitive impairments, and even suicidal tendencies in severe cases. Yet few studies have directed acupuncture's mechanism toward enhancing axonal repair correlated with synaptic plasticity and anti-inflammatory effects related to oxidative stress in the hippocampus. METHODS: Male Sprague-Dawley (SD) rats were randomly divided into control group (CON), chronic unpredictable mild stress (CUMS) group, CUMS + electroacupuncture group (EA), and CUMS + fluoxetine group (FLX) (n = 10/group). Rats were given a 28-day treatment at the Shangxing (GV23) and Fengfu (GV16) acupoints with electroacupuncture or fluoxetine (2.1 mg/kg). RESULTS: Rats exposed to CUMS induced depression-like behaviors and spatial learning-memory impairment, changed the ionized calcium binding adaptor molecule 1 (IBA-1), Vglut1, myelin basic protein (MBP), and postsynaptic density protein 95 (PSD95) level of hippocampal, increased the Nod-like receptor protein 3 (NLRP3), atypical squamous cell (ASC), Caspase level and hippocampal reactive oxygen species (ROS), and prompted the activation of Epha4-mediated signaling and an inflammatory response. Conversely, electroacupuncture administration reduced these changes and prevented depression-like behaviors and cognitive impairment. Electroacupuncture also promoted hippocampal expression of Sirtuin1(SIRT1), Nuclear factor erythroid 2-like (Nrf2), Heme oxygenase-1 (HO-1); reduced the expression of interleukin-1ß (IL-1ß), interleukin-18 (IL-18), and tumor necrosis factor-alpha (TNF-α); and prevented neural damage, particularly the synaptic myelin sheath, and neuroinflammation by regulating Eph receptor A4 (EphA4) in the hippocampal. CONCLUSION: These results indicate that electroacupuncture prevents depression-like behaviors with cognitive impairment and synaptic and neuronal damage, probably by reducing EphA4, which mediates ROS hyperfunction and the inflammatory response.
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Disfunção Cognitiva , Eletroacupuntura , Humanos , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Depressão/etiologia , Depressão/terapia , Fluoxetina/farmacologia , Doenças Neuroinflamatórias , Eletroacupuntura/métodos , Espécies Reativas de Oxigênio/metabolismo , Hipocampo/metabolismo , Estresse Oxidativo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Disfunção Cognitiva/metabolismo , Estresse Psicológico/complicações , Estresse Psicológico/terapiaRESUMO
Understanding the fate of exogenous fertilizer-derived inorganic phosphorus (Pi) is essential for effective P management. Hence, this study carried out a 180-day incubation experiment with or without KH2P18O4 in soils with four different fertilization regimes [without fertilizer (CK), mineral P and K fertilizer (PK), mineral N, P, and K fertilizer (NPK), compost (OM)]. We analyzed the atom % excess in phosphate oxygen isotope of sequentially extracted Pi pools (H2O-Pi, NaHCO3-Pi, NaOH-Pi, and HCl-Pi), soil respiration, potential phosphatase activities, and microbial biomass. Our results showed that exogenous phosphate fertilizer was immediately transformed into the H2O-Pi and NaHCO3-Pi pools and gradually partially immobilized in the HCl-Pi pool. Additionally, biotransformation plays an important role in the turnover of fertilizer-derived Pi. After the 180-day incubation, the biologically transformed H2O-Pi content was significantly (P<0.05) reduced by 63.2 % on average, with the largest reduction in PK. The NaHCO3-Pi gradually increased in both CK and OM through biotic processes. However, it continuously decreased in PK and NPK, likely due to the strong adsorption and microbial fixation. The NaOH-Pi fluctuated slightly in CK, NPK, and OM while gradually decreasing in PK. At the end of the incubation, 28.6 %, 37.0 %, 61.2 %, and 75.2 % of the Pi increment in CK, OM, NPK, and PK were stored in the HCl-Pi pool, respectively. Overall, these findings provide important information on the dynamics of fertilizer-derived Pi, delivering new insights into rational phosphate fertilizer management and sustainable agricultural development.
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Fertilizantes , Fósforo , Fertilizantes/análise , Fosfatos , Isótopos de Oxigênio , Oxigênio , Hidróxido de Sódio , Nitrogênio/análise , Solo , Agricultura/métodos , Microbiologia do Solo , FertilizaçãoRESUMO
Introduction: Conservation tillage is a widely used technique worldwide, but the effects of conservation tillage on bacterial community structure are poorly understood. We explored proportional alterations in the bacterial community under different tillage treatments. Methodology: Hence, this study utilized high-throughput sequencing technique to investigate the structure and assembly processes of microbial communities in different tillage treatments. Results and discussion: Tillage treatments included tillage no-straw retention (CntWt), no-tillage with straw retention (CntWntS), tillage with straw retention (CntWtS), no-tillage and no-straw retention (CntWnt). The influence of tillage practices on soil bacterial communities was investigated using Illumina MiSeq sequencing. Different tillage methods and straw retention systems significantly influenced soil parameters such as total potassium and pH were not affected by tillage practices, while straw retention significantly affected soil parameters including nitrogen content, available phosphorus and available potassium. Straw retention decreased bacterial diversity while increased bacterial richness. The effect of straw retention and tillage on bacterial communities was greater than with no tillage. Phylogenetic ß-diversity analysis showed that deterministic homogeneous selection processes were dominated, while stochastic processes were more pronounced in tillage without straw retention. Ecological network analysis showed that microbial community correlation was increased in CntWntS and CntWnt. Straw retention treatment significantly increased the relative abundance of bacterial taxa Proteobacteria, Bacteroidetes, and OD1, while Nitrospirae, Actinobacteria, and Verrucomicrobia significantly decreased. Conclusion: The conservation tillage practices significantly affect soil properties, bacterial composition, and assembly processes; however, further studies are required to investigate the impact of different crops, tillage practices and physiological characteristics on bacterial community structure and functions.
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This study reports on the field testing of a newly and originally designed laser absorption spectroscopy chamber (LASC) system based on closed dynamic chamber method, which is well suited for multi-point synchronous measurement of ammonia emissions in field multiple plot experiment. Main design feature of the LASC system is individual multi-reflection cells for each chamber, achieving the synchronous in-situ monitoring ammonia emissions of all the chambers. Two movable covers for automated opening and closing of the chamber, and the highly transparent chamber walls made of acrylic plate minimize the disturbance of the chamber deployment on the ammonia transport process in the chamber. Controlled field assessment experiment was conducted to evaluate the applicability and reliability of the LASC system. The results indicated that the optimum time length of chamber closure for monitoring ammonia emission is 3 min, and the appropriate time length of chamber ventilation is 17 to 37 min. The LASC system has higher accuracy for measuring ammonia emission rate and reliability for comparatively measuring ammonia emissions from different treatments than the traditional chamber methods.
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Poluentes Atmosféricos , Amônia , Amônia/análise , Poluentes Atmosféricos/análise , Reprodutibilidade dos Testes , Análise Espectral , Lasers , Monitoramento Ambiental/métodosRESUMO
The backward Lagrangian stochastic dispersion model in conjunction with open-path tunable diode absorption spectroscopy was used to quantify ammonia emissions from farmland based on the high-temporal resolution data, aiming to provide innovative achievements to diagnose patterns of ammonia flux. The results indicate that the bLS dispersion technique using open-path lasers to measure atmospheric ammonia concentrations is suitable for determining ammonia emissions from farmland continuously, especially for characterizing diurnal characteristics of NH3 emissions. The ammonia emissions have a significant diurnal pattern with two emission peaks from urea applied to maize on a calcareous sandy loam fluvo-aquic soil in the North China Plain. We believe that the first peak starting at approximately 9:00 am is due to NH3 absorbed by the dew re-emission at night as the dew evaporates. The maximum of ammonia flux at 14:00 corresponds to the peak of soil temperature and solar radiation. The ammonia emission increased rapidly, but the duration of emission peaks lasted approximately 4 d. Cumulative NH3 emission was 25.3% of the applied N over the entire measurement period. The NH3 emissions measured with bLS dispersion technique and venting method had certain difference.
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Amônia/análise , Modelos Teóricos , Solo/química , Análise Espectral/métodos , Zea mays/crescimento & desenvolvimento , Monitoramento AmbientalRESUMO
Conservation tillage is an advanced agricultural technology that seeks to minimize soil disturbance by reducing, or even eliminating tillage. Straw or stubble mulching in conservation tillage systems help to increase crop yield, maintain biodiversity and increase levels of exogenous nutrients, all of which may influence the structure of fungal communities in the soil. Currently, however, the assembly processes and co-occurrence patterns of fungal sub-communities remain unknown. In this paper, we investigated the effects of no-tillage and straw mulching on the composition, assembly process, and co-occurrence patterns of soil fungal sub-communities in a long-term experimental plot (15 years). The results revealed that combine straw mulching with no-tillage significantly increased the richness of fungi but not their diversity. Differential abundance analysis and principal component analysis (PCA) indicated that tillage management had a greater effect on the fungal communities of abundant and intermediate taxa than on the rare taxa. Available phosphorus (AP) and total nitrogen (TN) were the major determinants of fungal sub-communities in NT treatment. The abundant fungal sub-communities were assembled by deterministic processes under medium strength selection, while strong conservation tillage strength shifts the abundant sub-community assembly process from deterministic to stochastic. Overall, the investigation of the ecological network indicated that no-tillage and straw mulching practices decreased the complexity of the abundant and intermediate fungal networks, while not significantly influencing rare fungal networks. These findings refine our knowledge of the response of fungal sub-communities to conservation tillage management techniques and provide new insights into understanding fungal sub-community assembly.
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Professor LU Fan adheres to the principle in clinical practice, "the needling principle concentrated on regulating qi ". She takes the advantages of shallow needling technique of acupuncture in treatment of various diseases, e.g. exogenous disease, initial onset of disorder, chronic bi disorder, intractable diseases, disorder of yang nature, disorder of heat nature, thin body, pediatric diseases, disorders on the unilateral side of the body and acute diseases. Besides in compliance with classics, she has broadened the application scope of shallow needling technique of acupuncture and improved the clinical therapeutic effect.
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Terapia por Acupuntura , Acupuntura , Moxibustão , Pontos de Acupuntura , Criança , Humanos , Procedimentos Cirúrgicos VascularesRESUMO
Ammonia emission is one of the dominant pathways of nitrogen fertilizer loss from rice fields in China. It is difficult to measure ammonia emissions by high-frequency sampling with the chamber methods widely used in China, which is of great significance for investigating the environmental effects on the ammonia emissions. The chamber methods also can not accurately determine the ammonia emissions. In this study, the backward Lagrangian stochastic dispersion model, with ammonia concentrations continuously measured by the open-path tunable diode laser absorption spectroscopy technique, was used to determine ammonia emissions from a rice field after fertilizer application at excessive (270â¯kgâ¯N ha-1) and appropriate (210â¯kgâ¯N ha-1) rates in the Taihu Lake Region of China. High temporal resolution measurements of ammonia emissions revealed that high intraday fluctuations of ammonia emissions were significantly affected by the meteorological conditions. Multiple regression analysis showed a dominant solar radiation dependence of intraday ammonia emission cycles, especially during the rice panicle formation stage. The NH4+-N concentrations of the surface water of the rice field were found to be the decisive factor that influenced interday dynamics of ammonia emissions. Accurate quantifications of ammonia emissions indicated that the total ammonia losses under appropriate nitrogen application rate were 27.4â¯kgâ¯N ha-1 during the rice tillering stage and 11.2â¯kgâ¯N ha-1 during the panicle formation stage, which were 29.4% and 17.0% less than those under traditional excessive nitrogen application rate used by the local farmers, respectively. The ammonia loss proportions during the rice panicle formation stage were significantly lower than those of the tillering stage, which might be due to different nitrogen application rates and environmental effects during the two stages. This study indicated that the open-path tunable diode laser absorption spectroscopy technique could facilitate the investigation of high temporal resolution dynamic of ammonia emissions from farmland and the environmental influence on the ammonia emissions.
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Poluentes Atmosféricos/análise , Amônia/análise , Fertilizantes/análise , Nitrogênio/análise , Agricultura/métodos , China , Monitoramento Ambiental , Lagos/química , OryzaRESUMO
Reducing the applications of mineral phosphorus (P) fertilizers and supplementing them by organic fertilizers is becoming a necessary practice in the North China Plain due to overuse of mineral P fertilizers and improper disposal of organic wastes. Knowledge is needed about how the long-term substitution of mineral fertilizers by organic fertilizers affects soil P forms in order to understand soil P transformation and crop P uptake. In this study, we used solution 31P nuclear magnetic resonance (NMR) spectroscopy to characterize P forms in fluvo-aquic soil after 26â¯years of different fertilization management strategies, organic compost (OM), half compost in combination with half mineral fertilizer NPK (1/2 OM), mineral fertilizer NPK (NPK), mineral fertilizer NK (NK), and an unfertilized control (CK). Results showed that the P extraction efficiency using NaOH-EDTA varied from 13.0 to 27.7% for the soils of the treatments. 31P NMR spectra indicated that the majority of P was in the form of orthophosphate for all the treatments, which constituted 64.3-83.5% of the total extracted P. The application of P fertilizers significantly increased the concentrations of orthophosphate, monoesters and diesters regardless of the P fertilization method, although the proportions of monoesters and diesters were higher in CK. The proportions and concentrations of orthophosphate significantly decreased when all mineral fertilizers were replaced by compost. There was no significant difference in the proportions and concentrations of total organic P, corrected monoesters and diesters in NaOH-EDTA extracts of soils among NPK, 1/2OM and OM treatments. Decreasing mineral P fertilizers and partly replacing them by organic fertilizer in fluvo-aquic soil might increase soil test (Olsen) P and crop P uptake through the degradation of applied organic P forms.
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Infrared photoacoustic spectroscopy (PAS) is a new style to obtain data based on photoacoustic theory. Photoacoustic thoeory is based on the absorption of electromagnetic radiation by analyte molecules, and the absorbed energy is measured by detecting pressure fluctuations in the form of sound waves or shock pulses. In contrast to conventional absorption spectroscopy, PAS allows the determination of absorption coefficients over several orders of magnitude, even in very black and strongly scattering soil samples. Red soil, fulvic soil and paddy soil were collected from Fengqiu National Ecological Experimental Station, Yingtan Red Soil Experimental Station, and Changshu Ecological Experimental Station, respectively. These soil samples were used as experimental materials to characterize the Fourier transform mid-infrared photoacoustic spectra (FTIR-PAS). Compared with infrared transmittance spectra and reflectance spectra, the testing of FTIR-PAS spectra was very fast and convenient without any pr-treatment, and there were more abundant absorptions as well as appropriate absorption values in the spectra; The main soil components (kaolin, bentonite, sand and CaCO3) also showed several strong absorptions with specific characteristics in the spectra; Further more, the interference of water with the PAS spectra was significantly smaller than that with reflectance spectra. Therefore, the soil properties could be better characterized by FTIR-PAS. The principal components analysis based on the FTIR-PAS spectra indicated that there were two main principal components (PCA1, PCA2) which contained 98.17% variance of the spectra, and the two-dimensionol distribution was made by plotting these two principal components to classify the soil type, and the results indicated that this distribution could be applied to distinguish soil type, which provided new technique for soil identification as well as further quantitative analysis in soil science.
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Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise de Componente Principal , Radiação , Solo/análiseRESUMO
Irrigation and nitrogen (N) fertilization in excess of crop requirements are responsible for substantial nitrate accumulation in the soil profile and contamination of groundwater by nitrate leaching during intensive agricultural production. In this on-farm field trial, we compared 16 different water and N treatments on nitrate accumulation and its distribution in the soil profile (0-180cm), nitrate leaching potential, and groundwater nitrate concentration within a summer-maize (Zea mays L.) and winter-wheat (Triticum aestivum L.) rotation system in the Huang-Huai-Hai Plain over five cropping cycles (2006-2010). The results indicated that nitrate remaining in the soil profile after crop harvest and nitrate concentration of soil solutions at two depths (80cm and 180cm) declined with increasing irrigation amounts and increased greatly with increasing N application rates, especially for seasonal N application rates higher than 190kgNha-1. During the experimental period, continuous torrential rainfall was the main cause for nitrate leaching beyond the root zone (180cm), which could pose potential risks for contamination of groundwater. Nitrate concentration of groundwater varied from 0.2 to 2.9mgL-1, which was lower than the limit of 10mgL-1 as the maximum safe level for drinking water. In view of the balance between grain production and environmental consequences, seasonal N application rates of 190kgNha-1 and 150kgNha-1 were recommended for winter wheat and summer maize, respectively. Irrigation to the field capacity of 0-40cm and 0-60cm soil depth could be appropriate for maize and wheat, respectively. Therefore, taking grain yields, mineral N accumulation in the soil profile, nitrate leaching potential, and groundwater quality into account, coupled water and N management could provide an opportunity to promote grain production while reducing negative environmental impacts in this region.
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The development history, present situation, educational institution and association of acupuncture and moxibustion in Taiwan are reviewed. Acupuncture and moxibustion is considered as an invasive treatment in Taiwan, which has been introduced to Taiwan since the late Ming Dynasty and early Qing Dynasty, with a history of less than 400 years. At present, there are two acupuncture-related academic institutions and two educational institutions, which are all private. The acupuncture and moxibustion is applied for various diseases, and the cost is based on whether clinics and treatments are covered by medical insurance, so the differences are significant.
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Terapia por Acupuntura/tendências , Humanos , Moxibustão/tendências , Instituições Acadêmicas , TaiwanRESUMO
Professor ZHANG Yongshu, who studied from professor LIU Zhangjie, is a famous acupuncturist in Quanzhou of Southern Fujian. The publications authored by professor ZHANG Yongshu were collected in this study to summarize his academic characteristics of acupuncture and moxibustion. The result indicated he highly valued the regulation of yang qi, and established the theory of "developing yang to nourish yin", which proposes to develop yang qi to achieve the effect of culturing yin; he summarized eight methods to regulate the governor vessel and conception vessel, which can condition the body's yin and yang; he paid attention to moxibustion therapy and its dosage, and made the best of direct moxibustion. In addition, he focused on meridian theory with effective application of meridian syndrome differentiation; in clinical treatment, he regulated the hand-yangming meridian to treat diseases by nourishing yang, generating yin and regulating fu.