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1.
Biosci. j. (Online) ; 36(4): 1251-1260, 01-06-2020. graf, tab
Article in English | LILACS | ID: biblio-1147238

ABSTRACT

Melon (Cucumis melo L.) is a crop of great socioeconomic importance in regions with semiarid climate, as found in Northeast Brazil. In this region water deficit is a usual condition as well as the main reduction factor of plant productivity. Due to this phenomenon, irrigation techniques are used to make available the amount of water needed for plant production. Therefore, this study evaluated the physiology and fruit production changes of 'Juazeiro' Piel de sapo melon plants under different water replacement rates. 'Juazeiro' melon was grown under four reference evapotranspiration replacement rates (40, 60, 80 and 100% of ETo) distributed randomly in blocks with 5 replicates. The plants were cultivated in the field, in an experimental area located in the Brazilian Northeast region, under hot and dry semiarid climatic conditions, and during the growing cycle the 'Juazeiro' hybrid melon plants were evaluated for leaf area, biomass accumulation, gas exchange, photochemical efficiency of photosystem PSII and production of fruits per plant. Application of water replacement rates of 100% ETo leads to highest growth, net photosynthesis, and fruit yield of 'Juazeiro' melon. Water replacement at 80% ETo can be used for 'Juazeiro" melon under semiarid climatic conditions, but with small losses in fruit yield. Water replacement below 80% ETo leads to drastic reductions in growth, gas exchanges, quantum efficiency of photosystem II and fruit yield, which impairs melon production in semi-arid climate environments. KEYWORDS: Fruits yield. Gas exchange. Photochemical efficiency. INTRODUCTION Melon (Cucumis melo L.) is an important socioeconomic fruit cultivated in the world. Melon fruit production was 29.6 million tons and this production is distributed among China, Turkey, Iran, Egypt, India, United States, and Brazil. These countries account for 70% of the world production (FAO, 2017). In Brazil, cultivated area exceeded 22.000 ha with more than 521.6 thousand tons in 2015. 94.7% of this production was obtained in the semi-arid region of Northeast, mainly in the states of Ceará and Rio Grande do Norte, the largest producers in the country (IBGE, 2014). However, especially due to irregular rainfall, melon fruit production has been dropping in the last few years in this region. According to Pereira Filho et al. (2015), melon plants growth, development, and fruit production are greatly affected by climate conditions, mainly by water stress. Water stress is one of the most complex physiological phenomena because it is a multidimensional component which can considerably limit agricultural crops growth and development (DOGAN et al., 2008; LISAR et al., 2012; SILVA et al., 2015), generally in arid and semi-arid regions, such as in Northeast Brazil. Moreover, plant adaptability to water deficit conditions is related to a range of events occurring at several levels (LISAR et al., 2012), observed as a physiological, biochemical, and molecular adaptations, among others. At plant physiological level, soil water deficit has a significant effect on gas exchange, because it is a result of the limitation of stomatal conductance, and it is considered the primary cause of photosynthetic inhibition due to CO2 influx limitation, as well as water efflux from transpiration Received: 08/04/19 Accepted: 20/12/19


O meloeiro (Cucumis melo L.) é uma cultura de grande importância social e econômica mundial, principalmente em regiões de clima semiárido como o Nordeste brasileiro, onde déficit hídrico é condição comum e considerado o principal fator de redução da produtividade das plantas. Tal fenômeno força a utilização da irrigação como forma de disponibilizar a quantidade de água necessária à produção. Assim, objetivou-se com este trabalho avaliar as variações fisiológicas e produtivas de meloeiro pele-de-sapo submetidos a diferentes taxas de reposição hídrica. O híbrido 'Juazeiro' de melão pele-de-sapo foi cultivado sob quatro taxas de reposição da evapotranspiração de referência (40, 60, 80 e 100% da ETo), distribuídas em blocos ao acaso com 5 repetições. As plantas foram cultivadas em campo, em área experimental situada no Nordeste brasileiro, em condições clima semiárido quente e seco, e durante o ciclo de cultivo as plantas de meloeiro híbrido 'Juazeiro' foram avaliadas quanto a área foliar, o acúmulo de biomassa, as trocas gasosas, eficiência fotoquímica do fotossitesma PSII e produção de frutos por planta. A aplicação de taxas de reposição hídrica a 100% da ETo proporciona o maior crescimento, fotossíntese liquida e produção do meloeiro 'Juazeiro'. A reposição hídrica a 80% da ETo pode ser usada para o cultivo do meloeiro 'Juazeiro' em condições de clima semiárido, admitindo-se pequenas perdas no rendimento. A reposição hídrica com lâminas inferiores a 80% da ETo promove reduções drásticas no crescimento, trocas gasosas, eficiência quântica do fotossistema II e produção, que inviabilizam a produção do meloeiro em ambientes de clima semiáridos.


Subject(s)
Photochemistry , Semi-Arid Zone , Cucumis melo
2.
Braz. arch. biol. technol ; 63: e20180573, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132185

ABSTRACT

Abstract This work reports the study of the potential application of Zn/TiO2 catalysts, obtained by the sol-gel method, in processes of environmental decontamination through the reactions of photodegradation of textile dye, followed by electrospray mass spectrometry. The catalysts synthesis was performed according to a 2² factorial design with repetition at the central point. The characterization techniques used were: N2 adsorption measurements (BET method), scanning electron microscopy with energy dispersive X-ray (MEV/EDS), X-ray diffraction and point of zero charge (PZC). The photocatalytic tests were performed in batch in the presence of sunlight, and to evaluate the degradation kinetics study, a rapid direct injection electrospray mass spectrometry (DI-ESI-MS) method has been developed. By the photocatalytic tests, the calcination temperature of 400 °C has shown the best results of discoloration for the reactive Orange-122 dye (99.76%) in a reaction time of 2h. The discoloration kinetics were a pseudo-first order, and a statistical analysis was performed to investigate the effects of the variables and to optimize the conditions of discoloration to the dye. After the reactional time of 2 h, an ion of m/z 441.5 was detected by ESI-MS, indicating that the photocatalytic process was effective for the degradation of the dye to secondary compounds.


Subject(s)
Azo Compounds/toxicity , Biodegradation, Environmental , Decontamination/methods , Tandem Mass Spectrometry/methods , Environmental Restoration and Remediation/methods , Wastewater , Photochemistry , Textiles/toxicity , Microscopy, Electron, Scanning , Catalysis , Catalytic Domain , Spectrometry, Mass, Electrospray Ionization , Coloring Agents , Photobioreactors , Models, Theoretical
3.
Biosci. j. (Online) ; 35(1): 67-78, jan./fev. 2019. tab, graf
Article in English | LILACS | ID: biblio-1048561

ABSTRACT

In the semi-arid region of Northeast Brazil, water salinity is one of the main abiotic factors limiting crop growth and development. However, given the water scarcity affecting this region, the use of waters with moderate to high salt contents becomes necessary to irrigate crops. Thus, generating technologies that enable the use of saline waters is an essential alternative to the agricultural development of this region. In this context, this study aimed to evaluate photosynthesis, photochemical efficiency and growth of West Indian cherry, as a function of irrigation with saline waters and nitrogen (N) fertilization, in the post-grafting stage. The experiment was carried out in drainage lysimeters under greenhouse conditions, using a typic eutrophic Regolithic Neosol with sandy loam texture, in the municipality of Campina Grande-PB, Brazil. Treatments consisted of the combination between five levels of electrical conductivity of water ­ ECw (0.8; 1.6; 2.4; 3.2 and 4.0 dS m-1) and four N doses ­ ND (50; 75; 100 and 125 g of N plant-1 per year), arranged in a randomized block design, with 3 replicates. Gas exchanges, chlorophyll a fluorescence and growth of West Indian cherry were compromised by saline water irrigation, regardless of N dose. Irrigation with ECw higher than 0.8 dS m-1 caused damages to the photosystem II reaction centers of West Indian cherry. Nitrogen doses did not mitigate the deleterious effects caused by irrigation water salinity on photosynthesis, photochemical efficiency and growth of West Indian cherry.


Na região semiárida do Nordeste brasileiro, a salinidade da água é um dos principais fatores abióticos que restringem o crescimento e o desenvolvimento das culturas. Contudo, diante do quadro de escassez hídrica que afeta esta região, a utilização de águas com teores salinos de moderado a alto, faz-se necessário na irrigação das culturas. Desse modo, a geração de tecnologias que permitam o uso de águassalinas, constitui uma alternativa essencial para o desenvolvimento agrícola desta região. Neste contexto, objetivou-se com este trabalho avaliar a fotossíntese, eficiência fotoquímica e o crescimento da aceroleira, em função da irrigação com águas salinas e adubação nitrogenada, na fase pós-enxertia. O experimento foi conduzido em lisímetros de drenagem sob condições de casa-de-vegetação, utilizando-se um Neossolo Regolítico Eutrófico típico de textura franco-arenosa, no município de Campina Grande-PB. Os tratamentos foram constituídos da combinação entre cinco níveis de condutividade elétrica da água - CEa (0,8; 1,6; 2,4; 3,2 e 4,0 dS m-1) e quatro doses de nitrogênio ­ DN (50; 75; 100 e 125 g de N planta-1 por ano), distribuído no delineamento de blocos casualizados, com 3 repetições. As trocas gasosas, a fluorescência da clorofilaa e o crescimento da aceroleira foram comprometidos pela irrigação com águas salinas, independentemente da adubação com nitrogênio. A irrigação com CEa superior a 0,8 dS m-1 provocou danos nos centros de reação do fotossistema II da aceroleira. As doses de nitrogênio não mitigaram os efeitos deletérios ocasionados pela salinidade da água de irrigação sobre a fotossíntese, eficiência fotoquímica e o crescimento da aceroleira.


Subject(s)
Photochemistry , Photosynthesis , Saline Waters , Malpighiaceae , Agricultural Irrigation , Nitrogen
4.
Chinese Journal of Natural Medicines (English Ed.) ; (6): 721-731, 2016.
Article in English | WPRIM | ID: wpr-812563

ABSTRACT

The constituents of Cimicifuga plants have been extensively investigated, and the principal metabolites are 9, 19-cyclolanostane triterpenoid glycosides, which often exhibit extensive pharmacological activities. 9, 19-Cyclolanostane triterpenoid glycosides are distributed widely in genus Cimicifuga rather than in other members of the Ranunculaceae family. So far, more than 140 cycloartane triterpene glycosides have been isolated from Cimicifuga spp.. The aim of this review was to summarize all 9, 19-cyclolanostane triterpenoid glycosides based on the available relevant scientific literatures from 2000 to 2014. Biological studies of cycloartane triterpene glycosides from Cimicifuga spp. are also discussed.


Subject(s)
Animals , Humans , Cimicifuga , Chemistry , Drugs, Chinese Herbal , Chemistry , Pharmacology , Glycosides , Chemistry , Pharmacology , Photochemistry , Triterpenes , Chemistry , Pharmacology
5.
São Paulo; s.n; s.n; mar. 2015. 101 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-836698

ABSTRACT

Jacaranda decurrens Cham., Jacaranda caroba (Vell.) DC. e Piper umbellatum L. são plantas nativas do Brasil, presentes no estado de São Paulo, com relatos de uso popular para atividade antiúlcera. Este trabalho teve como objetivo avaliar a atividade antiúlcera de J. caroba, J. decurrens e formulações de nanocápsulas contendo P. umbellatum. Também pretendeu-se caracterizar a fitoquímica de tais formulações e extratos. Adicionalmente, foi avaliada a toxicidade aguda e subaguda de J. caroba. Os extratos de Jacaranda apresentaram compostos fenólicos em seus perfis cromatográficos obtidos por CCD e CLAE, característicos para cada espécie. Os diferentes extratos de J. caroba variaram sua composição química conforme a procedência e idade da planta. As espécies J. decurrens e J. caroba de três diferentes regiões não apresentaram ação antiúlcera aguda em ratos em modelo de indução por etanol acidificado, embora o extrato e as frações de J. caroba apresentaram potencial atividade anti Helicobacter pylori, com CIM variando entre 125 e 1.000 µg/mL. O extrato de J. caroba não promoveu sintomas de toxicidade aguda e subaguda em ratos. A DL50 observada foi maior que 5.000 mg/kg. Não foram relatadas alterações significativas na aparência macroscópica e peso dos órgãos, porém houve indicação de atividade mutagênica em teste de Ames na linhagem TA98 de S. typhimurium, o qual apresentou uma tendência dose-resposta para concentrações entre 7,5 e 15,0 mg/placa após ativação metabólica (S9). A formulação de nanocápsulas de poli-ε- caprolactona com extrato de P. umbellatum apresentou partículas com diâmetro médio de 181,6 ± 0,9 nm e potencial zeta de -31 ± 4 mV. Através de análise por CLAE observou-se maior eficiência de encapsulamento para a porção mais apolar da fração, enquanto que os compostos mais polares ficaram dispersos no meio. As nanocápsulas poliméricas apresentaram atividade gastroprotetora mesmo sem a adição de ativos e tiveram sua atividade aumentada pela fração clorofórmica de P. umbellatum


Jacaranda decurrens Cham., Jacaranda caroba (Vell.) DC. and Piper umbellatum L. are native plants in Brazil, present in the state of São Paulo, with popular usage reports for anti-ulcer activity. This study aimed to evaluate the anti-ulcer activity of J. caroba, J. decurrens and nanocapsules formulations containing P. umbellatum. Also, we intended to characterize the phytochemistry of such formulations and extracts. Additionally, we evaluated the acute and subacute toxicity of J. caroba. Extracts from Jacaranda presented phenolic compounds in their chromatographic profiles obtained by TLC and HPLC, with variations between species. Samples of J. caroba extracts showed different chemical composition according to the origin and age of the plant. The species J. decurrens and J. caroba from three different regions showed no acute anti-ulcer action when tested in rats by acidified ethanol induction model. However, extract and fractions from J. caroba showed potential anti Helicobacter pylori activity, with MIC ranging from 125 and 1,000 ug/mL. J. caroba extract did not cause symptoms of acute and subacute toxicity in rats. The DL50 was determined above 5,000 mg/kg. Also, there were no significant changes to the macroscopic appearance of organs or changes in their weights. Meanwhile, an indication of mutagenic activity was observed in the Ames test. The TA98 strain of S. typhimurium, showed a tendency of dose-response for concentrations between 7.5 and 15.0 mg/plate after metabolic activation (S9). The nanocapsules formulation of poly-ε-caprolactone containing P. umbellatum extract had an average particle diameter of 181.6 ± 0.9 nm and zeta potential of -31 ± 4 mV. HPLC analysis showed better entrapping efficiency for the more apolar portion of the fraction, while the more polar compounds were dispersed in the medium. The polymeric nanocapsules showed gastroprotective activity even without the addition of active molecules and had their activity increased by chloroform fraction of P. umbellatum


Subject(s)
Rats , Photochemistry , Jacaranda caroba/pharmacology , Malvaceae/classification , Pharmacognosy/classification , Stomach Ulcer/pathology , Phenolic Compounds/classification , Nanocapsules/analysis , Phytochemicals
6.
Invest. clín ; 55(2): 142-154, jun. 2014. ilus, tab
Article in English | LILACS | ID: lil-749972

ABSTRACT

In Latin America, people have largely abandoned the practice of wearing hats and traditional clothing that provided skin protection. Sunscreen application has therefore become essential to protect against the increased sun exposure. The physician-prescribed medical-grade sunscreens provide sufficient sun protection but the requirement for regular use puts a financial burden on the patient that is often not sustainable. An appropriate sunscreen should provide a high and broad ultraviolet (UV) protection against UVB and UVA. Several over-the-counter (OTC) sunscreens have been developed for sale at affordable prices and are available for purchase in convenient locations, such as local grocery stores. The aim of this study was to assess the in vitro UV protection of 34 popular OTC sunscreens found in the Latin American market. UV absorbance/transmittance was quantified by diffusion transmission spectroscopy using coarse silica plaques. Photostability was tested by irradiating them with simulated solar light and calculating the sun protection factor (SPF), critical length of absorption (C λ ), UVA/UVB ratio, and the spectral uniformity index (SUI). The results indicated that the in vitro SPFs were significantly lower than the value declared on the labels, particularly for those claiming high SPF values; however, the majority of these sunscreens offered high levels of UV protection. Considering the advantages of low cost and ample accessibility, we concluded that this sample of OTC sunscreens can be beneficial to the general public by providing some level of skin protection from solar radiation, and may be promoted to improve compliance with recommended photoprotection behavior.


En Latinoamérica, la población ha abandonado la costumbre de usar sombrero y ropa tradicional para protegerse del sol. En consecuencia, es básico el uso de protectores solares si se realizan actividades bajo sol. Los protectores solares que se usan en la práctica médica son adecuados, pero su uso frecuente condiciona una carga económica que muchos pacientes no pueden solventar debido a sus costos considerables. Un protector apropiado contiene una amplia y elevada protección ultravioleta (UV) A y B. En las tiendas de conveniencia, existen numerosos protectores solares a precios más accesibles. El objetivo del estudio fue determinar la protección UV in vitro de 34 protectores solares con amplia presencia comercial (de venta sin prescripción médica) en el mercado latinoamericano. La absorbancia/transmitancia de la radiación UV se cuantificó mediante espectroscopía de transmisión difusa. Placas de sílice esmerilado fueron recubiertas con el producto y expuestas a radiación solar simulada para conocer su fotoestabilidad. Se calcularon índices como el factor de protección solar (SPF), longitud crítica de absorción (C λ), relación UVA/UVB y el índice de uniformidad espectral (SUI). Se encontró que el SPF in vitro fue inferior al establecido en las etiquetas, especialmente en aquellos con valores altos. No obstante, la mayoría de los protectores incluidos ofrecen niveles de protección UV elevados. Considerando su amplia accesibilidad y menor costo, concluimos que esta muestra comercial de protectores solares podría utilizarse en el entorno clínico para favorecer su apego junto a las otras medidas de fotoprotección sugeridas.


Subject(s)
Sun Protection Factor , Sunscreening Agents/chemistry , Ultraviolet Rays , Absorption , Advertising , Drug Evaluation, Preclinical/instrumentation , Drug Evaluation, Preclinical/methods , In Vitro Techniques , Latin America , Photochemistry , Quartz , Spectrophotometry , Surface Properties , Sunscreening Agents/radiation effects
7.
Indian J Biochem Biophys ; 2014 Feb; 51(1): 19-28
Article in English | IMSEAR | ID: sea-154227

ABSTRACT

Photodynamic treatment (PDT) in combination with sonodynamic treatment (SDT) can be used as suitable methods to treat malignant and benign diseases or combat resistant bacteria. Both methods affect the production of reactive oxygen species (ROS). On the other hand, antioxidants are useful for cell protection against ROS. This work was aimed to study the effect of PDT and SDT treatments on the HeLa cell line using antioxidant Pronalen Sensitive Skin® as a protection from free radicals in the cells. We evaluated the effect of sensitizer ClAlPcS2 using battery of in vitro methods, including MTT assay, kinetic production of ROS, mitochondrial membrane potential change, type of cell death and microscopic analysis. Ultrasound treatment was observed to increase the production of ROS, only in combination with PDT, particularly at higher concentrations of ClAlPcS2. The added antioxidant acts as protection against free radicals and has potential as a dietary supplement against aging or free radicals. The results of study suggested that ClAlPcS2 could be used as a potential photosensitizer for treatment of a specific type of cancers.


Subject(s)
Antioxidants/pharmacology , Apoptosis/drug effects , Apoptosis/radiation effects , HeLa Cells , Humans , /drug effects , /radiation effects , Necrosis , Photochemistry , Photosensitizing Agents/pharmacology , Reactive Oxygen Species/metabolism , Ultrasonic Therapy
8.
Biosci. j. (Online) ; 30(1): 173-181, jan./feb. 2014. ilus, tab
Article in Portuguese | LILACS | ID: biblio-946987

ABSTRACT

O objetivo deste trabalho foi avaliar as respostas da cana-de-açúcar submetida à deficiência hídrica por meio de pigmentos fotossintéticos (clorofilas a, b, total a + b, relação clorofilas a/b e carotenoides) e verificar o uso do índice SPAD como ferramenta de diferenciação de cultivares. O experimento foi conduzido em casa de vegetação, onde quatro cultivares (IACSP95-5000, RB835054, RB928064 e SP80-3280) foram cultivadas em vasos. Após 65 dias do plantio, foram implementados dois tratamentos, sem deficiência (-D) e com deficiência hídrica (+D). Cultivares de canade- açúcar respondem diferentemente em relação aos pigmentos fotossintéticos quando submetidas à deficiência hídrica. As cultivares IACSP95-5000 e RB928064 têm menor efeito do estresse por falta de água, atribuído à capacidade da manutenção dos conteúdos de clorofilas e de carotenoides, além de maiores valores de índice SPAD, sob essa condição. A deficiência hídrica afeta com maior intensidade as cultivares RB835054 e SP80-3280 devido às maiores reduções nos pigmentos fotossintéticos e no índice SPAD. Índice SPAD é correlacionado com conteúdo de clorofilas e carotenoides em cana-de-açúcar e pode ser utilizado como técnica na seleção de cultivares tolerantes à deficiência hídrica em programas de melhoramento genético.


The objective of this study was to evaluate the responses of sugar cane subject to water stress by photosynthetic pigments (chlorophylls a, b, total a + b, ratio chlorophylls a/b and carotenoids) and verify the use of SPAD index as a cultivar differentiation tool. The experiment was carried out in a greenhouse, where four cultivars (IACSP95- 5000, RB835054, RB928064 and SP80-3280) were grown in pots. After 65 days of planting, two treatments were implemented, i.e., with no stress (-D) and with water stress (D +). Cultivars of sugar cane respond differently in relation to photosynthetic pigments when subjected to water deficit. Cultivars IACSP95-5000 and RB928064 have less effect of drought, that is attributed to the ability of maintaining the chlorophyll and carotenoid content, as well as higher SPAD index values under this condition. Water stress affects with more intensity the cultivars RB835054 and SP80-3280 due to higher reductions in photosynthetic pigments and SPAD index. SPAD index is correlated with chlorophyll and carotenoid content in sugar cane and can be used as a technique for selecting tolerant cultivars to drought in breeding programs.


Subject(s)
Photosynthesis , Carotenoids , Chlorophyll , Saccharum , Photochemistry
9.
Indian J Exp Biol ; 2013 Mar; 51(3): 262-268
Article in English | IMSEAR | ID: sea-147591

ABSTRACT

Carbon (neutral) based renewable liquid biofuels are alternative to petroleum derived transport fuels that contribute to global warming and are of a limited availability. Microalgae based biofuels are considered as promising source of energy. Lyngbya sp. and Synechococcus sp. were studied for the possibility of biodiesel production in different media such as ASNIII, sea water enrichment medium and BG11. The sea water enrichment medium was found superior in enhancing the growth rate of these microalgae. Nitrogen depletion has less effect in total chlorophyll a content, at the same time the lipid content was increased in both Lyngbya sp. and Synechococcus sp. by 1.4 and 1.2 % respectively. Increase in salinity from 0.5-1.0 M also showed an increase in the lipid content to 2.0 and 0.8 % in these strains; but a salinity of 1.5 M has a total inhibitory effect in the growth. The total biomass yield was comparatively higher in tubular LED photobioreactor than the fluorescent flat plated photobioreactor. Lipid extraction was obtained maximum at 60 ºC in 1:10 sample: solvent ratio. GC-MS analysis of biodiesel showed high content of polyunsaturated fatty acids (PUFA; 4.86 %) than saturated fatty acid (SFA; 4.10 %). Biodiesel production was found maximum in Synechococcus sp. than Lyngbya sp. The viscosity of the biodiesel was closely related to conventional diesel. The results strongly suggest that marine microalgae could be used as a renewable energy source for biodiesel production.


Subject(s)
Biofuels , Biomass , Bioreactors , Carbon/chemistry , Chlorophyll/metabolism , Cyanobacteria/metabolism , Energy-Generating Resources/economics , Equipment Design , Esters/chemistry , Gas Chromatography-Mass Spectrometry/methods , Lipids/chemistry , Microalgae , Nitrogen/metabolism , Photochemistry/methods , Solvents/chemistry , Synechococcus/metabolism , Triglycerides/chemistry , Viscosity
10.
São Paulo; s.n; 2013. 256 p. mapas, tab, ilus, graf.
Thesis in Portuguese | LILACS | ID: lil-713132

ABSTRACT

Objetivo. Demonstrar que a ocorrência de episódios críticos de poluição por ozônio na região de Cubatão-Centro é influenciada pelo aporte externo de poluentes, que participam dos processos físico-químicos de formação e remoção de reagentes fotoquímicos na atmosfera. Métodos. O estudo envolveu a obtenção e o tratamento de dados meteorológicos e de concentrações de poluentes fornecidos pela rede de monitoramento da qualidade do ar, bem como a realização de campanhas de amostragem passiva de ozônio (O ) e ativa de COVs, aldeídos e etanol na atmosfera da região. A amostragem de O VI 3 foi realizada com amostradores tipo Ogawa® e as concentrações foram determinadas por cromatografia iônica, com detecção por condutividade elétrica. Na amostragem de COVs foram utilizados tubos de aço contendo o adsorvente Tenax-GR, e a quantificação das amostras foi realizada por cromatografia gasosa e espectrometria de massas. A amostragem de aldeídos foi realizada com cartuchos de sílica gel revestido com 2,4 DNPH, e a quantificação realizada por cromatografia liquida de alta performance, com detector ultravioleta (UV/VIS). A amostragem de etanol foi realizada com cartuchos revestidos de florisil, e a quantificação realizada por flame ionization detector. O transporte de massas de ar foi analisado com base em backward trajectories, calculadas pelo modelo STILT. A interpretação dos dados foi realizada por estatística descritiva, boxplot, análise de correlação e análise multivariada (clusters). Resultados. A maioria dos episódios de ultrapassagem do PQAr de ozônio ocorreu no verão, entre 15h e 16h, com ventos predominantes de S/SE e velocidades superiores a 2,5m/s, típicos de períodos diurnos (brisa marítima). As espécies orgânicas precursoras de ozônio mais importantes foram: formaldeído, acetaldeído, tolueno, 1,2,3-trimetilbenzeno, m-xileno, etanol, oxileno, etilbenzeno, 1,3,5-trimetilbenzeno e benzeno. A retrotrajetória das massas de ar que chegam à Cubatão-Centro comprovou a influência de emissões exógenas. Os resultados obtidos na circulação de mesoescala, simulada pelo modelo BRAMS, concordam com os resultados obtidos por JAESCHKE (1997), onde apenas uma parcela da concentração média de poluentes de Cubatão-Centro era oriunda de fontes locais, sendo o restante decorrente do transporte de massas, com ocorrência de elevadas concentrações de poluentes com fluxo de direção norte-noedeste (brisa terrestre) e sul-sudeste (brisa marítima)


Subject(s)
Air Pollution , Air Pollution , Organic Chemicals/chemistry , Meteorology , Ozone/analysis , Photochemistry , Brazil , Environmental Monitoring
11.
Biocell ; 36(3): 105-111, Dec. 2012. graf, tab
Article in English | LILACS | ID: lil-694710

ABSTRACT

Chirostoma jordani is a native annual species inhabiting lacustrine waters of the Central Mexico Plateau. It is widely distributed and is currently facing high environmental pressures. Five experiments were performed to study the reproductive performance of this species. Four of the experiments were conducted in 270-L indoor recirculation tanks. Two males and one female at the first stage of reproduction were included in each test. A photoperiod of 14 light hours and 10 dark hours was used. In a fifth experiment, 10 females and 15 males were kept in an outdoor 3,000-L recirculation tank under natural photoperiod. The number of spawns, fertilised eggs and 30-day-old juveniles were counted and the survival rate was calculated. The results indicated significant differences (P< 0.05) between treatments. Higher spawn numbers and greater egg production were observed under controlled photoperiod, and higher numbers of juveniles and a higher survival rate were observed under natural photoperiod. The trials exhibited different patterns of egg production during the experiment. The egg production in the natural-photoperiod trials followed a polynomial curve model. In contrast, the trials under the controlled photoperiod showed an irregular pattern of increases and decreases in egg production.


Subject(s)
Animals , Female , Male , Fishes/metabolism , Reproduction , Biomass , Environment , Light , Mexico , Models, Statistical , Ovum/physiology , Oxygen/metabolism , Photoperiod , Phytoplankton , Photochemistry/methods , Seasons , Temperature , Time Factors , Water/chemistry
12.
Chinese Journal of Biotechnology ; (12): 164-171, 2011.
Article in Chinese | WPRIM | ID: wpr-324566

ABSTRACT

Global warming caused by the increasing CO2 concentration in atmosphere is a serious problem in the international political, economic, scientific and environmental fields in recent years. Intensive carbon dioxide capture and storage (CCS) technologies have been developed for a feasible system to remove CO2 from industrial exhaust gases especially for combustion flue gas. In these technologies, the biofixation of CO2 by microalgae has the potential to diminish CO2 and produce the biomass. In this review, the current status focusing on biofixation of CO2 from combustion flue gases by microalgae including the selection of microalgal species and effect of flue gas conditions, the development of high efficient photobioreactor and the application of microalgae and its biomass product were reviewed and summarized. Finally, the perspectives of the technology were also discussed.


Subject(s)
Air Pollutants , Metabolism , Air Pollution , Biodegradation, Environmental , Carbon Dioxide , Metabolism , Microalgae , Metabolism , Photochemistry
14.
Iranian Journal of Environmental Health Science and Engineering. 2011; 8 (4): 353-360
in English | IMEMR | ID: emr-124818

ABSTRACT

The possibility of linear alkyl benzene solfunate [LAS] photocatalytic degradation through application of TIO[2] nanoparticles was investigated. 10[mg/L] of LAS has been affected by either UV or TIO[2] and simultaneous use of both of them in separated experiments. Moreover, the effect of initial concentrations of LAS and TIO[2], pH, present various anions and different UV power was studied to determine the optimal operating conditions for LAS degradation in water. The amount of mineralization of LAS was reported by measuring the primary and final COD of the solution that was irradiated under optimized conditions. Maximum degradation was obtained at acidic pH, 50 mg/L of TIO[2] and 30 minute irradiation time. It was also shown that 99.5% of LAS was degraded in optimal conditions. Kinetic analysis indicated that photo catalytic degradation rates of LAS can be approximated by pseudo-first order model. Measuring the initial and final COD of illuminated solution under optimized conditions, indicated that almost complete mineralization of LAS was occurred. Based on the results, UV/TIO[2] process may be effectively applied in LAS removal in low concentrations but this process is not economically efficient in high concentrations


Subject(s)
Titanium/chemistry , Catalysis , Photochemistry , Nanoparticles , Ultraviolet Rays , /methods , /analysis
15.
Journal of Experimental Hematology ; (6): 227-230, 2011.
Article in Chinese | WPRIM | ID: wpr-244949

ABSTRACT

This study was aimed to evaluate the efficacy of riboflavin photochemical inactivation of virus in red blood cells by using animal models. human cytomegalovirus (HCMV) plus red blood cells were used as indicator, 30 BALA/c mice were divided into the experimental group (n = 10), virus control group (n = 10), visible light control group (n = 5) and red blood cell control group (n = 5). Mice in experimental group were inoculated with red blood cells inactive by the riboflavin photochemical, mice in virus control group was injected with red blood cells without riboflavin photochemical inactivation treatment, and mice in light control group was infused with red blood cells irradiated by visible light, and mice in red blood cells control group was injected with normal red blood cells. The virus was isolated in vitro from mice of various groups, the HCMV UL83 gene was detected by PCR, the PP65 antigen was identified by indirect immunofluorescence. The results indicated that the virus isolation, PCR detection and indirect immunofluorescence identification all showed positive in virus control group and visible light control group, while the results of detection in experimental and red blood cell control groups were negative. It is concluded that riboflavin photochemical viral inactivation of red blood cells is effective.


Subject(s)
Animals , Humans , Mice , Erythrocytes , Virology , Mice, Inbred BALB C , Models, Animal , Photochemistry , Riboflavin , Pharmacology , Virus Inactivation
16.
Jordan Journal of Pharmaceutical Sciences. 2010; 3 (2): 126-136
in English | IMEMR | ID: emr-118066

ABSTRACT

The photo-catalytic degradation of five pharmaceuticals using TiO[2] modified with SiO[2], and sun light was monitored. The initial concentrations used in the solar bath system were 100 microg/L for caffeine, diclofenac, glimepiride and ibuprofen, and 25 microg/L for methotrexate. Kinetic disappearance of caffeine, diclofenac, giimepiride and ibuprofen shows pseudo- first order kinetics, while methotrexate shows a zero order kinetic degradation which was monitored using HPLC/UV at lambda, = 225 nm, F = 1ml/min and on a C8 reversed phase column. The rate constants for diclofenac [wastewater 0.3238 sec[-1], distilled water 0.4057 sec[-1], glimepiride [wastewater 0.2203 sec[-1], distilled water 0.2771 sec[-1]], ibuprofen [wastewater 0.2802 sec[-1], distilled water 0.2411 sec[-1]], caffeine [distilled water 0.416 sec[-1]] and methotrexate [distilled water 3.1407 mole L[-1] sec[-1]]. The removal efficiency for the drugs was ranged between 79% and 96%


Subject(s)
Titanium/chemistry , Kinetics , Air Pollutants/chemistry , Photochemistry , Catalysis/radiation effects , Organic Chemicals/analysis , Environmental Monitoring , Oxidation-Reduction
17.
Iranian Journal of Health and Environment. 2010; 3 (2): 177-184
in Persian | IMEMR | ID: emr-122359

ABSTRACT

Cyanide is a species of high toxicity that found mostly in industrial effluents such as electroplating, metal mining, metallurgy and metal cleaning processes. Entrance of it to Existence environment contains very health hazardous. Purpose of this study, efficiency compare of both sonochemical and photosonochemical technologies for cyanide removal from aqueous solutions. In this study, it has been used from a productive set of 500w power ultrasound waves in of two frequencies 35 kHz and 130 kHz and a 125 W low pressure mercury lamp. Experiments were performed at initial cyanide concentrations varying from 2.5 to 75 mg/L. in this study, The effects of parameters such as pH, time and initial cyanide concentration on the sonochemical and photosonic degradation have been studied. The results of the study showed that the maximum removal efficiency of cyanide had been achieved sonochemical technology was 71% while it was 74% by photosonic at frequency of 130 kHz, at time of 90 min, pH of 11 and initial cyanide concentration of 2.5 mg/l. The results of the study showed that efficiency of photosonic process is more than for sonochemical cyanide removal from aqueous solutions. Also efficiency of cyanide removal has direct relationship with pH, frequency and time, and it has reverse relationship with cyanide concentration for both processes


Subject(s)
Photochemistry , Hydrogen-Ion Concentration , Indicators and Reagents , Ultrasonics , Water Pollutants, Chemical
18.
Claves odontol ; 16(63): 40-43, mayo 2009. ilus
Article in Spanish | LILACS | ID: lil-532921

ABSTRACT

En la odontología actual, existen varias opciones para el tratamiento de las alteraciones de color. Entre los procedimientos más conservadores, el blanqueamiento dental con soluciones de peróxido de hidrógeno en diferentes concentraciones, es uno de ellos. Si bien resultados más satisfactorios son obtenidos cuando la aplicación de los diferentes productos en determinadas concentraciones se prolonga en el tiempo, la utilización de peróxido de hidrógeno 35 por ciento aplicado sobre la superficie de dientes vitales, complementada con la activación por luz, es una opción cuando se necesitan resultados rápidos y cuando existen leves diferencias de color en el sector anterior. El siguiente caso clínico relata el tratamiento del segmento anterior con peróxido de hidrógeno 35 por ciento activado por fuente de luz.


Subject(s)
Humans , Male , Adult , Tooth Bleaching/methods , Tooth Discoloration/therapy , Photochemistry/methods , Hydrogen Peroxide/chemistry , Esthetics, Dental , Light , Dental Polishing/methods
19.
Journal of Biomedical Engineering ; (6): 138-143, 2009.
Article in Chinese | WPRIM | ID: wpr-280247

ABSTRACT

The aim of this study was to evaluate the changes in the expression of Bax, Bcl-2 and P53 when HeLa cells were induced by free cytokines or co-immobilized cytokines. The cells were induced for 24 hrs,72 hrs, 120 hrs and 168 hrs. Then, the expression of Bax, Bcl-2 and P53 was observed by immunohistochemistry. The average optic density of reaction products was tested by image analysis. Lastly, data were analyzed statistically. After the HeLa cells were induced for 120 hrs, the average optic denisity of Bcl-2 was much decreased. However, the average optic Bax was much increased. The average optic density of P53 also increased with the increase of time. The results suggest that HeLa apoptosis was induced by tumor necrosis factor-a and interferon -gamma, and the increasing expression of P53 may induce the expression of Bax and prevent the expression of Bcl-2, via the mitochondrial induction of cell apoptosis.


Subject(s)
Humans , Apoptosis , HeLa Cells , Immobilized Proteins , Pharmacology , Interferon-gamma , Pharmacology , Photochemistry , Methods , Proto-Oncogene Proteins c-bcl-2 , Metabolism , Tumor Necrosis Factor-alpha , Pharmacology , Tumor Suppressor Protein p53 , Metabolism , bcl-2-Associated X Protein , Genetics , Metabolism
20.
Journal of Research in Health Sciences [JRHS]. 2009; 9 (1): 1-6
in English | IMEMR | ID: emr-97345

ABSTRACT

There are great interests in photocatalytic oxidation of contaminants using titanium dioxide in recent years. The main objective of this research was to study photocatalytic disinfection of Coliform bacteria as water microbial pollution index using TiO[2] and a low pressure UV lamp in a batch reactor. The polluted water was prepared by adding a colony of Coliform in raw water and in separate stages was contacted with UV, TiO[2] and combination of them and various parameters such as contact time, pH and amount of TiO[2] were studied in terms of their effect on reaction progress. The results showed that in simultaneous presence of both UV ray and TiO[2], there was the most effective disinfection of Coliform. This study showed that 100% of Coliform was killed by irradiation for 60-75 min. in the presence of 0.8 gr 1[-1] TiO[2] in pH=7.0. Based on the results, UV/TiO[2] process may be effectively applied for disinfection of polluted water and can be suggested as a effective purifying method for water disinfection


Subject(s)
Water Pollution/prevention & control , Disinfection , Photochemistry , Oxidation-Reduction , Enterobacteriaceae , Titanium , Ultraviolet Rays , Ultraviolet Therapy
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