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1.
PLoS One ; 13(12): e0208525, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30521645

RESUMO

OBJECTIVE: To examine the possibility of diagnosing the double burden of malnutrition using estimated deviation values in low- and lower-middle-income countries. METHODS: A modified version of the Japanese Diagnostic Tool was used. Data on 194 countries were analyzed, including data from the United Nations International Children's Fund, World Health Organization and World Bank. After conducting a Box-Cox transformation, deviation values were calculated. The degree to which the values deviated relative to a deviation cutoff value of 50 was assessed. Focusing on countries with low- and middle-income economic levels, we examined the utility of this tool to show characteristic nutritional problems in each country. RESULTS: The deviation values had normal, distorted, bimodal, or trimodal distributions. In the lower-middle-income countries, almost all countries had values ranging from 40 to 60 for education and water environments (urban and rural), and the differences were minimal. However, different causes of noncommunicable disease-related deaths were considered, and the primary cause appeared to be related to lifestyle factors, particularly alcohol consumption and tobacco smoking. In comparison, the deviation values related to death among low-income countries also appeared to be related to differences in education and sanitation in urban and rural areas. CONCLUSION: The study results can help to determine the status of nutritional inequalities and plan country-specific strategies to reduce the double burden of malnutrition.


Assuntos
Monitoramento Epidemiológico , Disparidades nos Níveis de Saúde , Desnutrição/complicações , Doenças não Transmissíveis/epidemiologia , Pobreza , Adulto , Pré-Escolar , Escolaridade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Modelos de Riscos Proporcionais , Saneamento , Fatores Socioeconômicos , Qualidade da Água
2.
Environ Sci Pollut Res Int ; 22(8): 5762-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25388561

RESUMO

Livestock wastewater disposal onto rice paddy fields is a cost- and labor-effective way to treat wastewater and cultivate rice crops. We evaluated the influence of nitrogen loading rates on nitrogen assimilation by rice plants and on nitrogen losses (leaching and N2O emission) in forage rice fields receiving liquid cattle waste (LCW). Four forage rice fields were subjected to nitrogen loads of 107, 258, 522, and 786 kg N ha(-1) (N100, N250, N500, and N750, respectively) using basal fertilizer (chemical fertilizer) (50 kg N ha(-1)) and three LCW topdressings (each 57-284 kg N ha(-1)). Nitrogen assimilated by rice plants increased over time. However, after the third topdressing, the nitrogen content of the biomass did not increase in any treatment. Harvested aboveground biomass contained 93, 60, 33, and 31 % of applied nitrogen in N100, N250, N500, and N750, respectively. The NH4 (+) concentration in the pore water at a depth of 20 cm was less than 1 mg N L(-1) in N100, N250, and N500 throughout the cultivation period, while the NH4 (+) concentration in N750 increased to 3 mg N L(-1) after the third topdressing. Cumulative N2O emissions ranged from -0.042 to 2.39 kg N ha(-1); the highest value was observed in N750, followed by N500. In N750, N2O emitted during the final drainage accounted for 80 % of cumulative N2O emissions. This study suggested that 100-258 kg N ha(-1) is a recommended nitrogen loading rate for nitrogen recovery by rice plants without negative environmental impacts such as groundwater pollution and N2O emission.


Assuntos
Óxido Nitroso/metabolismo , Oryza/metabolismo , Amônia/análise , Animais , Bovinos , Produtos Agrícolas/metabolismo , Fertilizantes , Nitrogênio/metabolismo , Óxidos de Nitrogênio/análise , Óxido Nitroso/análise , Esgotos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Purificação da Água
3.
Environ Monit Assess ; 186(2): 845-58, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24114277

RESUMO

In this study, we focused on water quality in an urban canal and the Mekong River in the city of Can Tho, a central municipality of the Mekong Delta region, southern Vietnam. Water temperature, pH, electrical conductivity, BOD5, CODCr, Na(+), Cl(-), NH4 (+)-N, SO4 (2-)-S, NO3 (-)-N, and NO2 (-)-N for both canal and river, and tide level of the urban canal, were monitored once per month from May 2010 to April 2012. The urban canal is subject to severe anthropogenic contamination, owing to poor sewage treatment. In general, water quality in the canal exhibited strong tidal variation, poorer at lower tides and better at higher tides. Some anomalies were observed, with degraded water quality under some high-tide conditions. These were associated with flow from the upstream residential area. Therefore, it was concluded that water quality in the urban canal changed with a balance between dilution effects and extent of contaminant supply, both driven by tidal fluctuations in the Mekong River.


Assuntos
Cidades/estatística & dados numéricos , Monitoramento Ambiental , Rios/química , Poluentes da Água/análise , Abastecimento de Água/estatística & dados numéricos , Humanos , Vietnã
4.
Sci Total Environ ; 419: 178-86, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22289172

RESUMO

To evaluate global warming potential (GWP) on livestock waste treatment and biomass production in rice field, methane (CH(4)) and nitrous oxide (N(2)O) fluxes from forage rice fields planted with 4 different cultivars (Oryza sativa L. cv. Hamasari, Leafstar, Kusahonami and Takanari) were measured. Each of the cultivars were subjected either to basal fertilization alone (control plots) (84 kg N ha(-1)), or to basal fertilization plus topdressing with liquid cattle waste or LCW (treatment plots) (567 kg N ha(-1)). Liquid cattle waste application to the rice field resulted in peak CH(4) fluxes ranging from 22.0 to 32.1 mg m(-1)h(-1) during flooded conditions and large N(2)O fluxes ranging from 526 to 8591 µg m(-1)h(-1) after midsummer drainage and final drainage. The GWP of the control plots was between 1358 and 3872 kg CO(2)eq ha(-1), while the treatment plots ranged between 4503 and 8426 kg CO(2)eq ha(-1) and more than 60% of the GWP was from the N(2)O emission in treatment plots. In both the control and treatment plots, the lowest GWPs per ton of above-ground biomass were found to be from the Leafstar cultivar, which had a higher aboveground biomass than other cultivars; 117 kg CO(2)eq t(-1) from the control and 257 kg CO(2)eq t(-1) from the treatment plots. Thus, both forage production and suitable disposal of the LCW may be able to be achieved concomitantly with lower levels of GWP by cultivation of Leafstar in our field.


Assuntos
Poluentes Atmosféricos/análise , Metano/análise , Nitrogênio/farmacologia , Óxido Nitroso/análise , Oryza/efeitos dos fármacos , Esgotos/química , Poluentes Atmosféricos/metabolismo , Ração Animal/análise , Animais , Biomassa , Bovinos , Cromatografia por Troca Iônica , Fertilizantes , Inundações , Aquecimento Global , Japão , Metano/metabolismo , Nitrogênio/química , Óxido Nitroso/metabolismo , Oryza/genética , Esgotos/análise
5.
Aquat Toxicol ; 91(3): 262-9, 2009 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-19131120

RESUMO

In recent years, the exploration and development of the effective methods of treatment and prevention to algal blooms, especially Microcystis aeruginosa blooms has been an important issue in the field of water environment protection. Allelochemicals (natural plant toxins) are considered promising sources of algicides to control algal blooms. The objective of this study is to determine the inhibitory effects and potential mechanisms of a well-known allelochemical gramine (N,N-dimethyl-3-amino-methylindole) on bloom-forming cyanobacterium M. aeruginosa. The results showed that this indole alkaloid effectively inhibited the growth of M. aeruginosa. The effective concentration causing a 50% inhibition at 3 d (EC(50, 3 d)) increased with the initial algal density (IAD) increasing. When IAD increased from 5x10(4) to 5x10(5)cellsmL(-1), the values of EC(50, 3 d) increased from 0.5 to 2.1mgL(-1). In the cells of M. aeruginosa, gramine caused an obvious increase in the level of reactive oxygen species (ROS). The lipid-peroxidation product malondialdehyde (MDA) increased significantly in gramine-treated cells. The effects of gramine on enzymatic and non-enzymatic antioxidants were in different manners. The activity of superoxide dismutase (SOD) was decreased after gramine exposure. The catalase (CAT) activity was increased after 4h but decreased from 60h. Both the contents and the regeneration rates of ascorbic acid (AsA) and reduced glutathione (GSH) were increased after 4h of exposure to gramine. However, only GSH content was still increased after 40h of exposure. These results suggested that the activation of antioxidants in M. aeruginosa played an important role to resist the stress from gramine at initial time, the inactivation of SOD is crucial to the growth inhibition of M. aeruginosa by gramine, and the phytotoxicity of gramine on M. aeruginosa may be due to oxidative damage via oxidation of ROS.


Assuntos
Alcaloides/toxicidade , Antioxidantes/metabolismo , Água Doce , Microcystis/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Alcaloides Indólicos , Malondialdeído/metabolismo , Microcystis/química , Microcystis/crescimento & desenvolvimento , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
6.
Huan Jing Ke Xue ; 29(9): 2475-80, 2008 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19068629

RESUMO

Four aquatic plants (Alternanthera philoxeroides, Typha latifolia, Sagittaria sagittifolia, Phragmites communis ) were cultured on P-enriched soil in a pot experiment to assess the phosphorus rhizosphere depletion effect and analysis the ratio of root to shoot, root morphology, phosphorus uptake efficiency and phosphorus use efficiency. An obvious variation in P concentration of the soil in the rhizophere and non- rhizophere was observed. Compared with the non-rhizosphere (available P: 167.53 microg x g(-1)), the available P in the rhizosphere soil of Alternanthera philoxeroides, Typha latifolia, Sagittaria sagittifolia and Phragmites communis was reduced to 80.17, 124.37, 155.38 and 161.75 microg x g(-1) respectively, with 81%, 42%, 18% and 16% reduction ratio of water-soluble phosphorus. More effective phosphorus depletion was achieved in Alternanthera philoxeroides by higher phosphorus uptake efficiency (1.32 mg x m(-1)), while rooting system was small and phosphorus use efficiency was low (0.34 g x mg(-1)). Phosphorus uptake efficiency of Typha latjfolia is much lower (0.52 mg x m(-1)) than that of Alternanthera philoxeroides, however, its strong rooting system enhanced soil exploration, with higher phosphorus use efficiency (0.64 g x mg(-1)) and the ratio of root to shoot (0.35). Alternantshera philoxeroides and Typha latfolia were more effective in phosphorus depletion of the rhizosphere soil than that in Sagittaria sagittifolia and Phragmites communis.


Assuntos
Magnoliopsida/metabolismo , Fósforo/metabolismo , Poluentes do Solo/metabolismo , Áreas Alagadas , Amaranthaceae/metabolismo , Biodegradação Ambiental , Raízes de Plantas/metabolismo , Poaceae/metabolismo , Sagittaria/metabolismo , Especificidade da Espécie , Typhaceae/metabolismo
7.
Huan Jing Ke Xue ; 29(11): 3143-7, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19186818

RESUMO

To study the effects of allelochemicals of Arundo donax Linn. on the growth of Microcystis aeruginosa, the allelochemicals were extracted with three solvents (methanol, ethyl acetate and hexane), respectively. Based on the observation of algal morphology and the measurement of algal density and cell size, the results showed the allelochemicals extracted with all the three solvents had inhibition on M. aeruginosa. The appearance time of allelochemical inhibition increased as follows, allelochemicals extracted with methanol < ethyl acetate < hexane. As treatment time extended, M. aeruginosa regrew at low doses of allelochemicals extracted with methanol. Their inhibitory effects at high doses were lower than those extracted with ethyl acetate and hexane. After 2 d and 4 d of treatment, the inhibition ratios of allelochemicals extracted with ethyl acetate and hexane reached almost 100%, respectively. The 50% effective concentrations (EC50, 6 d) of allelochemicals extracted with methanol, ethyl acetate and hexane were 0.17 g x L(-1), 0.05 g x L(-1) and 0.08 g x L(-1), respectively. The allelochemicals extracted with methanol caused cavities in cells, those with ethyl acetate caused cells into cavities, pieces and conglomeration, and those with hexane caused goffers on cells initially with conglomeration later. The allelochemicals extracted with all the three solvents decreased the cell size of M. aeruginosa, among which those extracted with ethyl acetate had the strongest action.


Assuntos
Microcystis/crescimento & desenvolvimento , Feromônios/biossíntese , Feromônios/isolamento & purificação , Poaceae/metabolismo , Poluentes da Água/análise , Acetatos/química , Microcystis/efeitos dos fármacos , Solventes
8.
Bioresour Technol ; 98(10): 2018-26, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17070042

RESUMO

The separation of valuable chemicals from raw products, where a great number of chemicals coexist, is the key technology in biomass refinery. In this study, the applicability of membrane separation of valuable chemicals from our currently developed portable superheated steam (SHS) biomass pyrolysis process was demonstrated. Phenols (phenol, p-cresol, guaiacol, methyl guaiacol, and ethyl guaiacol), furfural, and acetone were successfully separated by pervaporation using the silicone rubber membrane from model solutions and an actual SHS derived aqueous solution. The solution was also concentrated effectively by reverse osmosis separation using a polyamide membrane. When a high concentration of SHS solution was fed to the pervaporation process, a phase-separated permeate was obtained, which indicated that the reverse osmosis concentration combined with pervaporation separation is useful for the superheated steam process.


Assuntos
Fracionamento Químico/métodos , Furaldeído/isolamento & purificação , Temperatura Alta , Membranas Artificiais , Fenóis/isolamento & purificação , Acetona/química , Acetona/isolamento & purificação , Biomassa , Fracionamento Químico/instrumentação , Furaldeído/química , Osmose , Fenóis/química , Soluções/química , Vapor
9.
Bioresour Technol ; 97(11): 1272-83, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16054811

RESUMO

To develop a novel noncatalytic biomass refinery process that can be used as a portable process, superheated steam pyrolysis was investigated to produce both carbonized solid fuels and chemicals using a large-scale reactor. Individual biomass components and native biomass (Sugi, Japanese cedar) were pyrolyzed. Between 150 and 400 degrees C, the vaporizing fractions of cellulose, xylan, and kraft lignin were summarized using a numerical model. Cellulose was converted to glycolaldehyde, furfural, 5-hydroxymethyl furfural and levoglucosan, whereas xylan was converted to glycolaldehyde, furfural, and acetic acid. Kraft lignin produced a slight yield of phenol and guaiacol. The total vaporization fraction of Sugi and its vaporizing rate were explained sufficiently using a numerical model based on the weighted average of the vaporizing properties of the individual components. However, the yields of phenol, guaiacol, and acetic acid were underestimated, while the yields of furfurals and levoglucosan were overestimated. Possible synergetic effects among chemicals in the superheated steam pyrolysis of native biomass were also discussed.


Assuntos
Biomassa , Cedrus/química , Temperatura Alta , Vapor , Madeira/química , Celulose/química , Japão , Lignina/química , Xilanos/química
10.
Water Res ; 39(16): 3900-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16131464

RESUMO

This paper presents an application of our newly developed adsorptive ozonation process using a high silica zeolite adsorbent (USY) for drinking water treatment. First, the adsorption of 2-methylisoborneol (2-MIB) on USY in a river water/pure water mixture was clarified by a batch-type adsorption experiment. The results showed that 2-MIB was adsorbed on USY; however, almost all of the adsorbed 2-MIB was desorbed over time. The desorption rate was increased with the ratio of river water to pure water, indicating that compounds dissolved in the river water, such as natural organic matter (NOM), prevent the adsorption of 2-MIB on USY. Second, the ability of the river water to consume ozone was confirmed in an experiment using a USY-packed column reactor. The ozone consumption was obviously increased by the presence of USY, indicating that USY-adsorbing compounds dissolved in the river water (probably small size NOM) consumed the ozone. However, the rapid ozone consumption was occurred by 6-8 s in the retention times when 3.14-4.38 mgL(-1) of water dissolved ozone was fed, this rapid ozone consumption lasted no more than these times. This result revealed that the rapid consumption of ozone by the adsorptive compounds in our process could be avoided within a certain retention time (6-8 s; especially for the river water used in this study) when enough concentration of ozone (3.14 mgL(-1) or more; same above) was supplied. We therefore performed a trial in which 2-MIB dissolved in river water was continuously decomposed using a USY-packed column with various ozone concentrations. In the process, the adsorptive compound dissolved in the river water adsorbed and reacted with ozone in the parts of the apparatus upstream of the column, while the adsorption and decomposition of 2-MIB took place in the parts of the apparatus downstream of the column. This resulted in a sufficient 2-MIB decomposition with minimizing bromate ion formation.


Assuntos
Canfanos/química , Oxidantes Fotoquímicos/química , Ozônio/química , Purificação da Água/métodos , Adsorção , Bromatos , Compostos Orgânicos , Rios , Zeolitas/química
11.
Water Res ; 39(13): 2926-34, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16029883

RESUMO

This work elucidates the applicability of our newly developed adsorptive ozonation process for the decomposition of 2-methylisoborneol (MIB), a typical taste and odor chemical, without the formation of possibly carcinogenic bromate ions. First, zeolite adsorbents were screened for their ability to adsorb MIB with a batch-type adsorption experimental apparatus and a flow-type decomposition experimental apparatus included an adsorbent-packed column. The USY zeolite with the highest silica to alumina ratio (SiO(2)/Al(2)O(3) molar ratio=70) showed the best performance as an adsorbent. Using this adsorbent, an ozonation experiment on an MIB solution including bromide ions was performed under various retention times using the flow-type apparatus. As a result, sufficient decomposition of MIB was achieved with preventing bromate formation.


Assuntos
Canfanos/isolamento & purificação , Ozônio/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Zeolitas/química , Adsorção , Óxido de Alumínio/química , Bromatos/química , Brometos/química , Canfanos/química , Odorantes , Oxidantes Fotoquímicos/química , Compostos de Potássio/química , Dióxido de Silício/química
12.
Water Res ; 38(1): 159-65, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14630113

RESUMO

The adsorption properties of water-dissolved ozone on high silica zeolites were investigated. Adsorbed ozone was desorbed almost reversibly. The adsorption equilibrium relations were described by a linear expression written as q=betaC, where q is the amount adsorbed, C is the equilibrium concentration and beta is the equilibrium constant. Also, the beta values were strongly dependent on the SiO(2)/Al(2)O(3) ratio (mol/mol) and on the pore structure of the high silica zeolites. The larger the SiO(2)/Al(2)O(3) ratio, the larger the value of beta. ZSM-5 (SiO(2)/Al(2)O(3) ratio: 3000), which gave the highest adsorption capacity of water-dissolved ozone, was able to highly concentrate water-dissolved ozone on the adsorbent. The decomposition behavior of adsorbed ozone was also investigated. Ozone adsorbed on high silica zeolite was observed to be a little more stable than ozone existing in bulk water. The decomposition rate was independent of SiO(2)/Al(2)O(3) ratios in the range of 30-3000 or a solution pH in the range of 4-6.


Assuntos
Ozônio/química , Eliminação de Resíduos Líquidos/métodos , Zeolitas/química , Adsorção , Concentração de Íons de Hidrogênio , Oxirredução , Dióxido de Silício/análise , Dióxido de Silício/química , Solubilidade , Água/química
13.
Water Res ; 38(1): 166-72, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14630114

RESUMO

We developed a novel ozonation process for water treatment using high silica zeolites as an adsorptive concentrator of water-dissolved ozone and organic pollutants, resulting in a significant increase in reaction rate. In experiments involving trichloroethene (TCE) decomposition using a tubular flow reactor, TCE decomposition was much greater in the presence of ZSM-5 (SiO(2)/Al(2)O(3) ratio=3000) than in its absence, possibly due to the high concentrations of ozone and TCE inside the adsorbent. The TCE conversion obtained in our experiments was found to reach its theoretically maximum limit.


Assuntos
Ozônio/química , Solventes/química , Tricloroetileno/química , Purificação da Água/métodos , Zeolitas/química , Adsorção , Cinética , Dióxido de Silício , Movimentos da Água
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