Altered Nitrogenous Pools Induced by the Azolla-Anabaena Azolla Symbiosis

Science.gov (United States)

Newton, Jack W.; Cavins, James F.

1976-01-01

The free amino acid and ammonia pools of Azolla caroliniana were analyzed by quantitative column chromatography on columns capable of separating all of the nitrogenous constituents normally found in physiological fluids. Comparisons were made of plants containing symbiotic algae and grown on nitrogen-free media, plants grown on media containing nitrate, and algae-free plants also grown on nitrate media. The major feature of the data was a very high level of intracellular ammonia found in plants which contain N2-fixing algal symbionts. In addition to the more usual amino acids, serine and cystathionine were found in the free amino acid pool. PMID:16659770

Methane emissions and microbial communities as influenced by dual cropping of Azolla along with early Rice

DEFF Research Database (Denmark)

Liu, Jingna; Xu, Heshui; Jiang, Ying

2017-01-01

Azolla caroliniana Willd. is widely used as a green manure accompanying rice, but its ecological importance remains unclear, except for its ability to fix nitrogen in association with cyanobacteria. To investigate the impacts of Azolla cultivation on methane emissions and environmental variables...... in paddy fields, we performed this study on the plain of Dongting Lake, China, in 2014. The results showed that the dual cropping of Azolla significantly suppressed the methane emissions from paddies, likely due to the increase in redox potential in the root region and dissolved oxygen concentration...... at the soil-water interface. Furthermore, the floodwater pH decreased in association with Azolla cultivation, which is also a factor significantly correlated with the decrease in methane emissions. An increase in methanotrophic bacteria population (pmoA gene copies) and a reduction in methanogenic archaea (16...

Aspects of nitrogen and carbon interchange in the Azolla-Anabaena symbiosis

International Nuclear Information System (INIS)

Peters, G.A.; Kaplan, D.; Meeks, J.C.; Buzby, K.M.; Marsh, B.H.; Corbin, J.L.

1985-01-01

The free-floating aquatic pteridophytes in the genus Azolla contain an N 2 -fixing cyanobacterium, Anabaena azollae, as a symbiont. Six extant species usually are recognized. In each species the symbiotic Anabaena can provide the total N requirement of the association via N 2 fixation and the Azolla sporophytes are capable of prolific vegetative reproduction in the absence of a combined N source. While vegetative reproduction and growth is more common, sexual reproduction occurs and presumably provides a means for survival during unfavorable environmental conditions. Azolla is heterosporous, producing both megasporocarps and microsporocarps on the same plant. Species demarcation is based primarily upon the morphology of these structures. Anabaena filaments are partitioned into both types of sporocarps during their development. The endophyte within the megasporocarp provides an inoculum for the developing sporophyte, maintaining the symbiosis. This report is restricted to studies conducted with the vegetatively propagated Azolla caroliniana - Anabaena azollae symbiosis grown on medium without combined N. It focuses on recent approaches to further elucidate aspects of host-endophyte interaction and incorporates analyses of soluble amino acids and ammonium, assays of ammonia assimilating enzymes, the use of [ 13 N]N 2 and the analysis of soluble sugars as well as 14 CO 2 -pulse chase studies. For orientation purposes the results are preceded by a description of the symbiosis. 39 references, 3 figures, 3 tables

Methane Emissions and Microbial Communities as Influenced by Dual Cropping of Azolla along with Early Rice

Science.gov (United States)

Liu, Jingna; Xu, Heshui; Jiang, Ying; Zhang, Kai; Hu, Yuegao; Zeng, Zhaohai

2017-01-01

Azolla caroliniana Willd. is widely used as a green manure accompanying rice, but its ecological importance remains unclear, except for its ability to fix nitrogen in association with cyanobacteria. To investigate the impacts of Azolla cultivation on methane emissions and environmental variables in paddy fields, we performed this study on the plain of Dongting Lake, China, in 2014. The results showed that the dual cropping of Azolla significantly suppressed the methane emissions from paddies, likely due to the increase in redox potential in the root region and dissolved oxygen concentration at the soil-water interface. Furthermore, the floodwater pH decreased in association with Azolla cultivation, which is also a factor significantly correlated with the decrease in methane emissions. An increase in methanotrophic bacteria population (pmoA gene copies) and a reduction in methanogenic archaea (16S rRNA gene copies) were observed in association with Azolla growth. During rice cultivation period, dual cropping of Azolla also intensified increasing trend of 1/Simpson of methanogens and significantly decreased species richness (Chao 1) and species diversity (1/Simpson, 1/D) of methanotrophs. These results clearly demonstrate the suppression of CH4 emissions by culturing Azolla and show the environmental and microbial responses in paddy soil under Azolla cultivation.

Identification of a common cyanobacterial symbiont associated with Azolla spp. through molecular and morphological characterization of free-living and symbiotic cyanobacteria.

Science.gov (United States)

Gebhardt, J S; Nierzwicki-Bauer, S A

1991-01-01

Symbiotically associated cyanobacteria from Azolla mexicana and Azolla pinnata were isolated and cultured in a free-living state. Morphological analyses revealed differences between the free-living isolates and their symbiotic counterparts, as did restriction fragment length polymorphism (RFLP) analyses with both single-copy glnA and rbcS gene probes and a multicopy psbA gene probe. RFLP analyses with Anabaena sp. strain PCC 7120 nifD excision element probes, including an xisA gene probe, detected homologous sequences in DNA extracted from the free-living isolates. Sequences homologous to these probes were not detected in DNA from the symbiotically associated cyanobacteria. These analyses indicated that the isolates were not identical to the major cyanobacterial symbiont species residing in leaf cavities of Azolla spp. Nevertheless, striking similarities between several free-living isolates were observed. In every instance, the isolate from A. pinnata displayed banding patterns virtually identical to those of free-living cultures previously isolated from Azolla caroliniana and Azolla filiculoides. These results suggest the ubiquitous presence of a culturable minor cyanobacterial symbiont in at least three species of Azolla. Images PMID:1685078

Nitrogen fixation by the Azolla-Anabaena azollae symbiosis

International Nuclear Information System (INIS)

Becking, J.H.

1985-01-01

A concise outline is presented on the main characteristics of the Azolla association in relation to tropical wetland rice cultivation and the nitrogen economy of paddy soils. Due to the presence of a nitrogen fixing cyanobiont occurring in a special leaf cavity of the Azolla leaf, the water fern Azolla can grow in a nitrogen-deficient environment and is able to contribute considerably to the nitrogen status of the soil. An experimental set-up is presented for how the nitrogen-fixing capacity of Azolla plants can be measured in the field by means of the acetylene reduction assay using a rather simple glass vessel. A comparison was made between 15 N 2 fixation by Azolla and acetylene reduction of Azolla plants under identical conditions

Determining biotoxins in continental waters colonised by Azolla; Determinacion de biotoxinas en aguas continentales colonizadas por Azolla

Energy Technology Data Exchange (ETDEWEB)

Prada A-Buylla, J.; Sanchez Crespo, R.; Verdigo Althofer, M. [Confederacion Hidrografica del Guadina. Ciudad Real (Spain)

1999-07-01

During the period 1993-95, the presence of Azolla ferns was observed in the air/water interface along several kilometres of the river Guadina in both Spain and Portugal. This fern is symbiotically associated with the cyano-bacteria Anabaena azollae that is capable of fixing atmospheric nitrogen, which can lead to vegetable growth and eutrophication. At the same time, the cyanobacteria may generate biotoxins, in which case a study is made of the hepatotoxins forming a family of 53 related cyclic peptides. Those consisting of seven aminoacids receive the name of microcystines, while formed by five aminoacids arc called nodulaincs. Chromatography was used to determine the presence of these peptides in the water from six sampling points. Microcystine-LR was found at concentrations of around 0.3 g/l at three points. (Author) 5 refs.

Pengaruh Pemberian Tepung Azolla Fermentasi (Azolla microphylla Terhadap Performa Ayam Kampung Persilangan

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A. Raras

2017-02-01

Full Text Available Penelitian bertujuan untuk mengkaji pengaruh penggunaan tepung Azolla microphylla fermentasi terhadap performans ayam kampung persilangan. Materi penelitian adalah 80 ekor ayam kampung umur 5 minggu, ayam kampung ini persilangan antara ayam kampung keturunan Bangkok dan Lohman 202 dari peternakan rakyat Temanggung dengan bobot badan 469,80 ± 38 gram (CV = 3,33%. Bahan pakan yang digunakan yaitu jagung, bungkil kedelai, tepung ikan, pollard, bekatul, CaCO3, premix dan tepung azolla fermentasi. Fermentasi azolla menggunakan larutan EM4 dengan perbandingan 3 gram : 10 ml. Perlakuan pakan T0 (ransum basal tanpa tepung azolla fermentasi, T1 (ransum mengandung tepung azolla fermentasi 10%, T2 (ransum mengandung tepung azolla fermentasi 15% dan T3 (ransum mengandung tepung azolla fermentasi 20%. Kandungan protein pakan 17% dan energi metabolis 2800 kkal/kg. Penelitian menggunakan Rancangan Acak Lengkap (RAL dengan 4 perlakuan dan 4 ulangan. Parameter yang diamati adalah konsumsi ransum, pertambahan bobot badan dan konversi ransum. Data dianalisis dengan analisis ragam. Hasil penelitian menunjukkan bahwa perlakuan penggunaan tepung azolla terfermentasi berpengaruh nyata (P<0,05 terhadap konsumsi pakan dan pertambahan bobot badan, sedangkan hasil penelitian perlakuan penggunaan azolla terfermentasi tidak berpengaruh nyata (P<0,05 terhadap konversi pakan. Kesimpulan dari penelitian ini adalah pemberian tepung azolla terfermentasi dapat meningkatkan konsumsi pakan dan pertambahan bobot badan pada perlakuan T2, sedangkan untuk konversi pakan pada perlakuan penggunaan tepung azolla terfermentasi menurun.

[The genetic diversity and homology of Anabaena azollae and its host plant (Azolla) based on rapd analysis].

Science.gov (United States)

Chen, Jian; Zheng, Wei-wen; Xu, Guo-zhong; Song, Tie-ying; Tang, Long-fei

2002-01-01

Symbiotic Anabeana azollae and its host plant Anabeana-free Azolla were isolated from 16 Azolla accessions representing different Azolla species or geographic origins.DNA polymorphic fragments were obtained by simultaneous RAPD amplification of both symbiont and host. The UPGMA clusters of Anabeana azollae and its host Azolla were established separately based on Dice coefficient caculation and a coordinated relationship was shown between Anabeana azollae and its Azolla host along both individual genetic divergence,but this genetic homology was reduced among different strains within Azolla species while the obvious mutants of Anabeana azollae were detected in some Azolla tested strains collected from different geographic area in the same host species.

Potential of macrophytes for removing atrazine from aqueous solution Potencial de macrófitas para remoção de atrazine de solução aquosa

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F.P Guimarães

2011-01-01

Full Text Available The potential of three macrophytes, Azolla caroliniana, Salvinia minima, and Lemna gibba was assessed in this study to select plants for use in environmental remediation contaminated with atrazine. Experiments were carried out in a greenhouse over six days in pots containing Hoagland 0.25 strength nutritive solution at the following atrazine concentrations: 0; 0.01; 0.1; 1.0; 10.0 mg L-1. Decrease in biomass accumulation was observed in the three macrophytes, as well as toxic effects evidenced by the symptomatology developed by the plants which caused their deaths. The chlorosis and necrosis allowed to observe in the plants the high sensitivity of the three species to the herbicide. Plants presented low potential for removal of atrazine in solution when exposed to low concentrations of the herbicide. However, at the 10.0 mg L-1 atrazine concentration, L. gibba and A. caroliniana showed potential to remove the herbicide from the solution (0.016 and 0.018 mg atrazine per fresh mass gram, respectively. This fact likely resulted from the processes of atrazine adsorption by the dead material. The percentage of atrazine removed from the solution by the plants decreased when the plants were exposed to high concentrations of the pollutant. Azolla caroliniana, S. minima, and L. gibba were not effective in removing the herbicide from solution. The use of these species to remedy aquatic environments was shown to be limited.Avaliou-se, neste estudo, o potencial de três macrófitas - Azolla caroliniana, Salvinia minima e Lemna gibba - com vistas à seleção de plantas para remediação de ambientes contaminados por atrazine. Foram realizados experimentos em casa de vegetação durante seis dias, em vasos contendo solução nutritiva Hoagland (0,25 de força iônica, nas seguintes concentrações de atrazine: 0; 0,01; 0,1; 1,0; e 10,0 mg L-1. A redução da biomassa acumulada pelas macrófitas foi observada, bem como os efeitos de toxidez evidenciados pela

Biosolubilization of uranyl ions in uranium ores by hydrophyte plants

International Nuclear Information System (INIS)

Cecal, Alexandru; Calmoi, Rodica; Melniciuc-Puica, Nicoleta

2006-01-01

This paper investigated the bioleaching of uranyl ions from uranium ores, in aqueous medium by hydrophyte plants: Lemna minor, Azolla caroliniana and Elodea canadensis under different experimental conditions. The oxidation of U(IV) to U(VI) species was done by the atomic oxygen generated in the photosynthesis process by the aquatic plants in the solution above uranium ores. Under identical experimental conditions, the capacity of bioleaching of uranium ores decreases according to the following series: Lemna minor > Elodea canadensis > Azolla caroliniana. The results of IR spectra suggest the possible use of Lemna minor and Elodea canadensis as a biological decontaminant of uranium containing wastewaters. (author)

An ecophysiological study of the Azolla filiculoides- Anabaena azollae association

Science.gov (United States)

van Kempen, Monique; Smolders, Fons; Speelman, Eveline; Reichart, Gert Jan; Barke, Judith; Brinkhuis, Henk; Lotter, Andy; Roelofs, Jan

2010-05-01

The long term effects of salinity stress on the growth, nutrient content and amino acid composition of the Azolla filiculoides - Anabaena azollae association was studied in a laboratory experiment. It was demonstrated that the symbiosis could tolerate salt stress up to 90 mM NaCl, even after a 100 day period of preconditioning at salt concentrations that were 30 mM NaCl lower. In the 120 mM NaCl treatment the Azolla filiculoides survived, but hardly any new biomass was produced. It was shown that during the experiment, A. filiculoides became increasingly efficient in excluding salt ions from the plant tissue and was thus able to increase its salt tolerance. The amino acid analysis revealed that the naturally occurring high glutamine concentration in the plants was strongly reduced at salt concentrations of 120 mM NaCl and higher. This was the result of the reduced nitrogenase activity at these salt concentrations, as was demonstrated in an acetylene reduction assay. We suggest that the high glutamine concentration in the plants might play a role in the osmoregulatory response against salt stress, enabling growth of the A. filiculoides -Anabaena azollae association up to 90 mM NaCl. In a mesocosm experiment it furthermore was demonstrated that Azolla might manipulate its own microenvironment when grown at elevated salt concentration (up to ~50 mmol•L-1) by promoting salinity stratification, especially when it has formed a dense cover at the water surface. Beside salt stress, we also studied the growth of Azolla filiculoides in response to elevated atmospheric carbon dioxide concentration, in combination with different light intensities and different pH of the nutrient solution. The results demonstrated that as compared to the control (ambient pCO2 concentrations), Azolla filiculoides was able to produce twice as much biomass at carbon dioxide concentrations that were five times as high as the ambient pCO2 concentration. However, it was also shown that this

Molecular identification of Azolla invasions in Africa: The Azolla specialist, Stenopelmus rufinasus proves to be an excellent taxonomist

Science.gov (United States)

Biological control of Azolla filiculoides in South Africa with the Azolla specialist Stenopelmus rufinasus has been highly successful. However, field surveys showed that the agent utilized another Azolla species, thought to be the native Azolla pinnata subsp. africana, which contradicted host specif...

Modulation of cadmium-induced phytotoxicity in Cabomba caroliniana by urea involves photosynthetic metabolism and antioxidant status.

Science.gov (United States)

Huang, Wenmin; Shao, Hui; Zhou, Sining; Zhou, Qin; Li, Wei; Xing, Wei

2017-10-01

Urea is a widespread organic pollutant, which can be a nitrogen source, playing different roles in the growth of submerged macrophytes depending on concentrations, while high cadmium (Cd) concentrations are often toxic to macrophytes. In order to evaluate the combined effect of urea and Cd on a submerged macrophyte, Cabomba caroliniana, the morphological and physiological responses of C. caroliniana in the presence of urea and Cd were studied. The results showed that high concentrations of urea (400mgL -1 ) and Cd (500µmolL -1 ) had negative effects on C. caroliniana. There were strong visible symptoms of toxicity after 4 days of exposure under Cd-alone, 400mgL -1 urea, and Cd+400mgL -1 urea treatments. In addition, 400mgL -1 urea and Cd had adverse effects on C. caroliniana's pigment system. Significant losses in chlorophyll fluorescence and photosynthetic rates, as well as Rubisco activity were also observed under Cd-alone, 400mgL -1 urea, and Cd+400mgL -1 urea treatments. 400mgL -1 urea markedly enhanced Cd toxicity in C. caroliniana, reflected by a sharp decrease in photosynthetic activity and more visible toxicity symptoms. The results of thiobarbituric acid reactive substances (TBARS) pointed to extreme oxidative stress in C. caroliniana induced under Cd or 400mgL -1 urea exposure. Exogenous ascorbate (AsA) protected C. caroliniana from adverse damage in 400mgL -1 urea, which further corroborated the oxidative stress claim under 400mgL -1 urea. However, results also demonstrated that lower urea concentration (10mgL -1 ) alleviated Cd-induced phytotoxicity by stimulating chlorophyll synthesis and photosynthetic activity, as well as activating the activity of catalase (CAT) and glutathione-S-transferase (GST), which may explain the alleviating effect of urea on C. caroliniana under Cd stress. Copyright © 2017 Elsevier Inc. All rights reserved.

DIVERSITY AND HOST SPECIFICITY OF AZOLLA CYANOBIONTS(1).

Science.gov (United States)

Papaefthimiou, Dimitra; Van Hove, Charles; Lejeune, André; Rasmussen, Ulla; Wilmotte, Annick

2008-02-01

A unique, hereditary symbiosis exists between the water fern Azolla and cyanobacteria that reside within a cavity in the dorsal leaf-lobe of the plant. This association has been studied extensively, and questions have frequently been raised regarding the number and diversity of cyanobionts (cyanobacterial symbionts) among the different Azolla strains and species. In this work, denaturating gradient gel electrophoresis (DGGE) and a clone library based on the 16S rRNA gene were used to study the genetic diversity and host specificity of the cyanobionts in 35 Azolla strains covering a wide taxonomic and geographic range. DNA was extracted directly from the cyanobacterial packets, isolated after enzymatic digestion of the Azolla leaves. Our results indicated the existence of different cyanobiont strains among Azolla species, and diversity within a single Azolla species, independent of the geographic origin of the host. Furthermore, the cyanobiont exhibited host-species specificity and showed most divergence between the two sections of genus Azolla, Azolla and Rhizosperma. These findings are in agreement with the recent redefinition of the taxon Azolla cristata within the section Azolla. With regard to the taxonomic status of the cyanobiont, the genus Anabaena of the Nostocaceae family was identified as the closest relative by this work. © 2008 Phycological Society of America.

Hydrogen uptake by Azolla-Anabaena

International Nuclear Information System (INIS)

Ruschel, A.P.; Freitas, J.R. de; Silva, P.M.

1984-01-01

The hydrogen uptake in the Azolla-Anabaena system is studied. Tritium is used as tracer. Plants are incubated under different atmosphere composition: a) Air + 3 H 2 ; b) Air + CO 2 + 3 H 2 + CO; c) Air + 3 H 2 + CO; d) Air + CO 2 + 3 H 2 + CO to study the pathway of absorbed hydrogen in the Azolla - Anabaena system. Azolla-Anabaena showed greater hydrogen uptake under argonium atmosphere than under air. Carbon monoxide decreased hydrogen uptake. There are evidences of recycling of the hydrogen evolved through notrogenease. (Author) [pt

Azolla domestication towards a biobased economy?

Science.gov (United States)

Brouwer, Paul; Bräutigam, Andrea; Külahoglu, Canan; Tazelaar, Anne O E; Kurz, Samantha; Nierop, Klaas G J; van der Werf, Adrie; Weber, Andreas P M; Schluepmann, Henriette

2014-05-01

Due to its phenomenal growth requiring neither nitrogen fertilizer nor arable land and its biomass composition, the mosquito fern Azolla is a candidate crop to yield food, fuels and chemicals sustainably. To advance Azolla domestication, we research its dissemination, storage and transcriptome. Methods for dissemination, cross-fertilization and cryopreservation of the symbiosis Azolla filiculoides-Nostoc azollae are tested based on the fern spores. To study molecular processes in Azolla including spore induction, a database of 37 649 unigenes from RNAseq of microsporocarps, megasporocarps and sporophytes was assembled, then validated. Spores obtained year-round germinated in vitro within 26 d. In vitro fertilization rates reached 25%. Cryopreservation permitted storage for at least 7 months. The unigene database entirely covered central metabolism and to a large degree covered cellular processes and regulatory networks. Analysis of genes engaged in transition to sexual reproduction revealed a FLOWERING LOCUS T-like protein in ferns with special features induced in sporulating Azolla fronds. Although domestication of a fern-cyanobacteria symbiosis may seem a daunting task, we conclude that the time is ripe and that results generated will serve to more widely access biochemicals in fern biomass for a biobased economy. No claim to original European Union works. New Phytologist © 2014 New Phytologist Trust.

Research on some functions of Azolla in CELSS system

Science.gov (United States)

Liu, Xiaofeng; Min, Chen; Xia-shi, Liu; Chungchu, Liu

This article detailed the possibility of using Azolla in CELSS system, the characters of Azolla; the experiments on using Azolla as O 2-releasing plant to provide O 2 for human in airtight chamber; using Azolla as an important biological part for urine solution purification was also introduced.

Azolla domestication towards a biobased economy?

NARCIS (Netherlands)

Brouwer, Paul; Brautigam, A.; Kulahoglu, C.; Tazelaar, A.O.E.; Kurz, S.; Nierop, K.G.J.; Werf, van der A.K.; Weber, A.P.M.; Schluepmann, H.

2014-01-01

Due to its phenomenal growth requiring neither nitrogen fertilizer nor arable land and its biomass composition, the mosquito fern Azolla is a candidate crop to yield food, fuels and chemicals sustainably. To advance Azolla domestication, we research its dissemination, storage and transcriptome.

Azolla domestication towards a biobased economy?

NARCIS (Netherlands)

Brouwer, Paul; Bräutigam, A.; Külahoglu, C.; Tazelaar, A.O.E.; Kurz, S.; Nierop, K.G.J.; van der Werf, A.; Weber, A.P.M.; Schlupmann, Henriette

Due to its phenomenal growth requiring neither nitrogen fertilizer nor arable land and its biomass composition, the mosquito fern Azolla is a candidate crop to yield food, fuels and chemicals sustainably. To advance Azolla domestication, we research its dissemination, storage and transcriptome.

Stratigraphy and paleoenvironment of the Danish Eocene Azolla event

Science.gov (United States)

Heilmann-Clausen, Claus; Beyer, Claus; Snowball, Ian

2010-05-01

Spores (massulae and megaspores) of the freshwater fern Azolla are recorded in several Danish Eocene outcrops and boreholes. The Azolla-bearing interval is 0.5 - ca. 3 m thick and occurs within the L2 Bed, a unit in the lower part of the hemipelagic, bathyal Lillebælt Clay Formation deposited in the central and eastern parts of the North Sea Basin. Intervals of organic-rich clay, usually including two distinctive, black sapropels, are present in the lower part of Bed L2, indicating a generally reduced oxygen content in the bottom waters during this time, with at least two episodes of severe, basinwide stagnation. The oxygen-deficit points to reduced circulation and/or enhanced marine productivity in the North Sea Basin. Azolla occurs in the upper part of this mainly organic-rich interval. The frequency of Azolla spores relative to marine dinoflagellate cysts fluctuates within the interval. The Azolla interval has previously been correlated to levels near the Ypresian/Lutetian transition in Belgium, based on dinoflagellate stratigraphy. Calibration of a new magnetostratigraphic study of the lower Lillebælt Clay with the dinoflagellate biostratigraphy suggests that Bed L2 spans the upper part of Chron 22r, C22n and lower part of C21r. The Azolla pulse spans the upper part of C22n and lowermost part of C21r. The combined bio-magnetostratigraphy from Denmark allows a detailed comparison with published data from the northern part of the Norwegian-Greenland Sea (ODP Hole 913B). The correlation confirms earlier assumptions, which were based on biostratigraphy alone, that the marine Azolla pulse in the two areas, and therefore probably over the whole Norwegian-Greenland Sea - North Sea region, is of the same age. An ongoing palynological study of the L2 Bed has so far revealed no indication for freshwater episodes or brackish waters in the basin during the Azolla pulse, except perhaps for Azolla itself. It is, therefore, suggested that the Azolla spores were transported

Use of azolla as a nitrogen source of lowland rice

International Nuclear Information System (INIS)

Sisworo, E.L.; Widjang, H.S.; Havid, S.; Hendratno; Soleh, S.; Goesworo, S.

1991-01-01

A four years experiment has been carried out to study possibility of using azolla as a nitrogen source for lowland rice. The work done in the first year, experiments were conducted in the wet season (WS) and the dry season (DS) of 1984/1985, was evaluate weather azolla could really increase rice yield. In the second year, experiments done in the WS and DS of 1985/1986, N-derived from azolla (N-dfA) and N-derived from urea (N-dfU) in rice plan were determined. The third year work done in the WS and DS of 1986/1987 was conducted to see what extend azolla could be applied in the terms of kg N/ha as a N-source for rice. While the last year was devoted to study the N-balance of azolla and urea, which was done in the DS of 1988/1989. Results of the experiments show that azolla has the same ability as urea to increase rice azolla interacted with urea. By increasing the azolla level N recovery in rice will decrease. The same phenomena was also found with urea. Another interesting fact is that an azolla cover in the rice field could promote N-uptake from urea. (author). 8 refs, 15 tabs

ANALISIS BEBERAPA UNSUR KIMIA KOMPOS Azolla mycrophylla

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Sri Utami Lestari

2018-02-01

Full Text Available The most consumed part of the plants is the leaf part so that the fertilizer provided should contain high nitrogen (N. The nature of the N fertilizer is volatile and when the rainy season there can be washing.  When plants deficienci nutrients shows symtoms of yellowing leaves so that the application of N fertilizer to the plant must remain unfulfilled.  Azolla is a usable alternative.  Azolla has a high N nutrient content because it is symbiotic with anabaena in binding to free nitrogen in the air.            The purpose of this study was to determine the chemical composition (pH,N,P,K Azolla mycrophylla.  The experiment was conducted experimentally with the first stage of composting azolla after it was done chemical analysis in the laboratory.  The result of this research can be concluded that chemical analysis of Azolla mycrophylla cpmpost is as follows :pH 7,17, N 2,57%, P 0,34%, K 0,03%. 

Mosquito larval productivity in rice-fields infested with Azolla in Mvomero District, Tanzania.

Science.gov (United States)

Mwingira, V S; Mayala, B K; Senkoro, K P; Rumisha, S F; Shayo, E H; Mlozi, M R S; Mboera, L E G

2009-01-01

Azolla (Salviniales: Azollaceae) is known to reduce oviposition and adult emergence of a number of mosquito species. Several species of Azolla are reportedly indigenous to Tanzania. However, the potential of Azolla as a biocontrol agent against malaria mosquitoes has not been evaluated in the country. This cross-sectional study was carried out to assess mosquito larval productivity in irrigated rice-fields infested with Azolla in Mvomero District, Tanzania. A systematic larval sampling covering all open water bodies along designed transect was carried in rice-fields. Larval density was estimated by dipping water bodies with or without Azolla. The degree of Azolla coverage was categorized as 0%, 80%. Larvae densities were categorised as low ( or = 500/m2) productivity. A total of 120 water bodies were surveyed and 105 (87.5%) had Azolla microphyla and A. pinnata at varying degrees of coverage. Of the total 105 water bodies with Azolla, 80 (76.2%) had a green Azolla mat, and 25 (23.8%) a brown Azolla mat. Eighty-eight (73.3%) of the sites were infested with anophelines and 109 (90.8%) with culicine larvae. Seventy percent of all water bodies contained anophelines and culicines in sympatric breeding, while 20.8% and 3.3% had only culicines and anophelines, respectively. The majority (82%) of mosquito breeding sites were found in area with Azolla substrate. Mosquito larva productivity was low in sites with highest (>80%) Azolla coverage. Seventy-two (81.8%) of the anopheline and 90 (82.6%) culicine breeding sites were infested with Azolla. Water bodies infested with green Azolla were more productive than those covered by brown coloured Azolla substrates for both culicines (13%) and anophelines (8%). Of the 1537 field collected larvae that hatched to adult stage, 646 (42.03%) were Anopheles gambiae s.l., 42 (2.73%) were An. funestus and 769 (50.03%) were Culex quinquefasciatus. These findings suggest that the mosquito productivity is low when the Azolla coverage is high

Pengaruh pemberian Azolla (Azolla microphyla, Kaulfuss dan mikroorganisme efektif terhadap produksi rumput raja (Pennisetum purpureum, Schumacher & Thonn c.v King

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Erna Yuniati

2013-12-01

Full Text Available The research aims at determining the influence of azolla compost and effective microorganism (EM application on the production of King Grass at the 1st and the 2nd cuttings at Sumbersekar field laboratory, Faculty of Animal Husbandry Brawijaya University for four months. The Randomized Block Factorial design was applied with two factors. The first factor was EM4 consists of E1 (EM4 addition and E0 (without EM4. The second factor was the dosage of fertilizer consists of A100 (100% azolla + 0% urea, A75 (75% azolla + 25% urea, A50 (50% azolla + 50% urea, A25 (25% azolla + 75% urea and A0 (0% azolla + 100% urea. The parameters observed comprised the number of tillers, plant height, dry matter (DM leaf production, organic matter (OM content, crude protein (CP content. The study indicates that there were interaction (P<0.05 between EM4 and fertilizer (azolla dosage on plant height, total OM, total CP, DM leaf production, DM stem production, total DM production, and total CP production at the first cutting. Then, at the second cutting there were interaction (P<0.05 among treatments on the number of tillers, total OM, total CP, DM leaf pro-duction, total DM production, and total CP. At the first cutting, the highest values of plant height, leaf OM, stem OM, leaf CP, stem CP, OM production were 86.39%, 92.40%, 7.85%, and 3.89% respectively found at ElA25. Furthermore, at the second cutting the best treatment were ElA25 in which the value of leaf CP content and total DM content were 8.08% and 4.64 kg/plot respectively. The leaf DM production and stem OM content at the first cutting were higher than those at the second cutting. It can be concluded that azolla can substitute the role of urea by 25%.

Azolla--a model organism for plant genomic studies.

Science.gov (United States)

Qiu, Yin-Long; Yu, Jun

2003-02-01

The aquatic ferns of the genus Azolla are nitrogen-fixing plants that have great potentials in agricultural production and environmental conservation. Azolla in many aspects is qualified to serve as a model organism for genomic studies because of its importance in agriculture, its unique position in plant evolution, its symbiotic relationship with the N2-fixing cyanobacterium, Anabaena azollae, and its moderate-sized genome. The goals of this genome project are not only to understand the biology of the Azolla genome to promote its applications in biological research and agriculture practice but also to gain critical insights about evolution of plant genomes. Together with the strategic and technical improvement as well as cost reduction of DNA sequencing, the deciphering of their genetic code is imminent.

Mosquito larval productivity in rice-fields infested with Azolla in ...

African Journals Online (AJOL)

Abstract: Azolla (Salviniales: Azollaceae) is known to reduce oviposition and adult emergence of a number of mosquito species. Several species of Azolla are reportedly indigenous to Tanzania. However, the potential of Azolla as a biocontrol agent against malaria mosquitoes has not been evaluated in the country.

PENGARUH DOSIS P DALAM FOSFAT ALAM PADA PENINGKATAN BIOMASA Azolla microphylla Kaulfuss

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Mahmudah Hamawi

2015-12-01

Full Text Available Azolla microphylla is one of the green resources fertilizer, adding natural P respectively will increase the biomass including. The on time embedding of azolla are able to provide nutrition to the plants such as rice especially N. The experiment was conducted in Desember 2nd , 2006 - April 5th , 2007 in Tegalgondo, Karangploso, Malang, East Java ( 550 m up sea level. The experiment applied Randomized Block Design (RBD under two factors, dose and embedding time with three replications. The doses were applied are P0 = 0 kg ha-1; P1 = 25 kg P ha-1; P2 = 50 kg P ha-1; and P3 = 75 kg P ha-1 . The embedding times were a day before planting, 50 % azolla in 14, 28 and 24 days after planting, 50 % azolla in 21 and 49 days after planting, and 50 % azolla in 35 day after planting. The parameters of observation were wet weigh of azolla; N, P , K contents before and after treatments and azolla decompositions. The result showed 75 kg P ha-1 with interaction of azolla embedding, was the most effective dose to increased azolla biomass.

Response of yield and yield components of rice (Oryza sativa L. cv. Tarom Hashemi in rice, duck and Azolla (Azolla sp. farming

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M Gharavi Baigi

2016-05-01

Full Text Available In order to evaluate the yield and yield components of rice (Oryza sativa L. cv. Tarom Hashemi in integrated rice, duck and Azolla, an experiment was conducted at the Research Farm of Sari University of Agricultural Sciences and Natural Resources during 2012. Experiment was arranged in split plot based on a randomized complete block design with three replications. The number of ducks as main plots at four levels (0, 400, 800 and 1200 ducks.ha-1 and Nitrogen source as sub plots at four levels (without Azolla and nitrogen, Azolla, Azolla+nitrogen and nitrogen were the treatments. Analysis of variance showed highly significant differences for the number of ducks, Azolla+nitrogen and their interaction effects of plant height, number of tillers.plant-1, number of panicle.plant-1, number of grains.panicle-1, panicle weight, panicle dry weight and grain yield. The results revealed that the highest values of plant height (133 cm, number of tillers (38 tillers.plant-1, number of panicle (24 numbers.plant-1, number of grains (171 numbers.panicle-1, panicle weight (23 g, panicle dry weight (13 g and grain yield (4 t.ha-1 were recorded in 1200 duck pieces per hectare while treated with Azolla (500 g.m-2 and nitrogen (50 kg.ha-1. In conclusion, results of the current experiment showed that increasing of duck number from 400 to 1200 pieces.ha-1 along with Azolla and nitrogen could enhance the yield and yield components of rice (Tarom Hashemi cultivar.

Lead accumulation in the aquatic fern Azolla filiculoides.

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Oren Benaroya, Rony; Tzin, Vered; Tel-Or, Elisha; Zamski, Eli

2004-01-01

In this study, we characterized lead (Pb2+) accumulation and storage by the aquatic fern Azolla filiculoides. Lead precipitates were detected in the vacuoles of mesophyll cells of Azolla plants cultured for 6 d in rich growth medium containing 20 mg l(-1) Pb2+. Energy dispersive spectroscopy (EDS) analysis of the relative element content of leaves collected from these plants revealed a 100% increase in the levels of P, S, Na and Ca and a 40% decrease in Mg and Cl compared to the untreated plants. Both Azolla whole plants and isolated apoplasts were incubated for 6 d in 20 mg l(-1) Pb2+. Lead content in the whole plant composed 0.37%, 2.3% and 1.8% of the dry weight after 2, 4 and 6 d of growth, respectively, while the isolated Azolla apoplast contained 0.125%, 1.22% and 1.4% Pb2+, respectively. Lead content in Azolla whole plant increase by 200%, 100% and 22% after 2, 4 and 6 d of growth, respectively, when compared to Azolla apoplast. Dark, electron dense deposits of lead were observed in light and transmission electron microscope in leaf cells treated with lead. All the observed lead deposits were localized in vacuoles while larger lead deposits were found in mature leaves than in young leaves. No lead deposits were found in cells of the cyanobiont Anabaena when the plants were exposed to similar conditions. Activity and content of V-H+-ATPase were studied in Azolla plants grown in the presence of 20, 40 and 80 mg l(-1) of lead for a period of 4 d. Activity of V-H+-ATPase was increased by 190%, 210% and 220%, respectively, but the content of V-H+-ATPase was reduced by all lead concentrations. Copyright 2004 Elsevier SAS

Na(+) regulation by combined nitrogen in Azolla pinnata-Anabaena azollae symbiotic association during salt toxicity.

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Singh, Satya S; Singh, Santosh K; Mishra, Arun K

2008-01-01

To study the regulation of Na(+) ion by combined-N sources in Azolla pinnata-Anabaena azollae, Na(+) influx, intracellular Na(+) and Na(+) efflux were investigated in the presence of different N-sources (N(2), NH(4)(+), NO(3)(-) and urea) and various NaCl concentrations. Sodium influx by Azolla pinnata fronds was minimum in the presence of NO(3)(-). Almost identical levels of intracellular sodium, although less than N(2) and NH(4)(+) incubated fronds were observed in the presence of NO(3)(-) and urea. Efflux of sodium was minimum in urea and NO(3)(-) grown fronds. A low residual sodium was observed in the fronds incubated in NO(3)(-) and urea supplemented media. Results suggest that nitrate and urea curtailed the entry of sodium, reduced salt toxicity maximally by maintaining the minimum level of sodium and also conserved energy due to slow influx and efflux of Na(+) within the fronds during salt shock and the process of adaptation.

Response of nitrogen-fixing water fern Azolla biofertilization to rice crop.

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Bhuvaneshwari, K; Singh, Pawan Kumar

2015-08-01

The water fern Azolla harbors nitrogen-fixing cyanobacterium Anabaena azollae as symbiont in its dorsal leaves and is known as potent N 2 fixer. Present investigation was carried out to study the influence of fresh Azolla when used as basal incorporation in soil and as dual cropped with rice variety Mahsoori separately and together with and without chemical nitrogen fertilizer in pots kept under net house conditions. Results showed that use of Azolla as basal or dual or basal plus dual influenced the rice crop positively where use of fern as basal plus dual was superior and served the nitrogen requirement of rice. There was marked increase in plant height, number of effective tillers, dry mass and nitrogen content of rice plants with the use of Azolla and N-fertilizers alone and other combinations. The use of Azolla also increased organic matter and potassium contents of the soil.

The Eocene Arctic Azolla bloom: environmental conditions, productivity and carbon drawdown.

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Speelman, E N; Van Kempen, M M L; Barke, J; Brinkhuis, H; Reichart, G J; Smolders, A J P; Roelofs, J G M; Sangiorgi, F; de Leeuw, J W; Lotter, A F; Sinninghe Damsté, J S

2009-03-01

Enormous quantities of the free-floating freshwater fern Azolla grew and reproduced in situ in the Arctic Ocean during the middle Eocene, as was demonstrated by microscopic analysis of microlaminated sediments recovered from the Lomonosov Ridge during Integrated Ocean Drilling Program (IODP) Expedition 302. The timing of the Azolla phase (approximately 48.5 Ma) coincides with the earliest signs of onset of the transition from a greenhouse towards the modern icehouse Earth. The sustained growth of Azolla, currently ranking among the fastest growing plants on Earth, in a major anoxic oceanic basin may have contributed to decreasing atmospheric pCO2 levels via burial of Azolla-derived organic matter. The consequences of these enormous Azolla blooms for regional and global nutrient and carbon cycles are still largely unknown. Cultivation experiments have been set up to investigate the influence of elevated pCO2 on Azolla growth, showing a marked increase in Azolla productivity under elevated (760 and 1910 ppm) pCO2 conditions. The combined results of organic carbon, sulphur, nitrogen content and 15N and 13C measurements of sediments from the Azolla interval illustrate the potential contribution of nitrogen fixation in a euxinic stratified Eocene Arctic. Flux calculations were used to quantitatively reconstruct the potential storage of carbon (0.9-3.5 10(18) gC) in the Arctic during the Azolla interval. It is estimated that storing 0.9 10(18) to 3.5 10(18) g carbon would result in a 55 to 470 ppm drawdown of pCO2 under Eocene conditions, indicating that the Arctic Azolla blooms may have had a significant effect on global atmospheric pCO2 levels through enhanced burial of organic matter.

Aquatic plant Azolla as the universal feedstock for biofuel production.

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Miranda, Ana F; Biswas, Bijoy; Ramkumar, Narasimhan; Singh, Rawel; Kumar, Jitendra; James, Anton; Roddick, Felicity; Lal, Banwari; Subudhi, Sanjukta; Bhaskar, Thallada; Mouradov, Aidyn

2016-01-01

The quest for sustainable production of renewable and cheap biofuels has triggered an intensive search for domestication of the next generation of bioenergy crops. Aquatic plants which can rapidly colonize wetlands are attracting attention because of their ability to grow in wastewaters and produce large amounts of biomass. Representatives of Azolla species are some of the fastest growing plants, producing substantial biomass when growing in contaminated water and natural ecosystems. Together with their evolutional symbiont, the cyanobacterium Anabaena azollae, Azolla biomass has a unique chemical composition accumulating in each leaf including three major types of bioenergy molecules: cellulose/hemicellulose, starch and lipids, resembling combinations of terrestrial bioenergy crops and microalgae. The growth of Azolla filiculoides in synthetic wastewater led up to 25, 69, 24 and 40 % reduction of NH 4 -N, NO 3 -N, PO 4 -P and selenium, respectively, after 5 days of treatment. This led to a 2.6-fold reduction in toxicity of the treated wastewater to shrimps, common inhabitants of wetlands. Two Azolla species, Azolla filiculoides and Azolla pinnata, were used as feedstock for the production of a range of functional hydrocarbons through hydrothermal liquefaction, bio-hydrogen and bio-ethanol. Given the high annual productivity of Azolla, hydrothermal liquefaction can lead to the theoretical production of 20.2 t/ha-year of bio-oil and 48 t/ha-year of bio-char. The ethanol production from Azolla filiculoides, 11.7 × 10 3  L/ha-year, is close to that from corn stover (13.3 × 10 3  L/ha-year), but higher than from miscanthus (2.3 × 10 3  L/ha-year) and woody plants, such as willow (0.3 × 10 3  L/ha-year) and poplar (1.3 × 10 3  L/ha-year). With a high C/N ratio, fermentation of Azolla biomass generates 2.2 mol/mol glucose/xylose of hydrogen, making this species a competitive feedstock for hydrogen production compared with other bioenergy crops

Orbitally-forced Azolla blooms and middle Eocene Arctic hydrology; clues from palynology

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Barke, Judith; Abels, Hemmo A.; Sangiorgi, Francesca; Greenwood, David R.; Sweet, Arthur R.; Donders, Timme; Lotter, Andre F.; Reichart, Gert-Jan; Brinkhuis, Henk

2010-05-01

The presence of high abundances of the freshwater fern Azolla in the early Middle Eocene central Arctic Ocean sediments recovered from the Lomonosov Ridge during IODP Expedition 302, have been related to the presence of a substantial freshwater cap. Azolla massulae, belonging to the newly described Eocene species Azolla arctica Collinson et al., have been found over at least a ~4 m-thick interval. There are strong indications that Azolla has bloomed and reproduced in situ in the Arctic Ocean for several hundreds of thousands of years. Possible causes for the sudden demise of Azolla at ~48.1 Ma include salinity changes due to evolving oceanic connections or sea-level change. Distinct cyclic fluctuation in the Azolla massulae abundances have previously been related to orbitally forced climate changes. In this study, we evaluate the possible underlying forcing mechanisms for these freshwater cycles and for the eventual demise of Azolla in an integrated palynological and cyclostratigraphical approach. Our results show two clear periodicities of ~1.3 and ~0.7 m in all major aquatic and terrestrial palynomorph associations, which we can relate to obliquity (41 ka) and precession (~21 ka), respectively. Cycles in the abundances of Azolla, freshwater-tolerant dinoflagellate cysts, and swamp vegetation pollen show co-variability in the obliquity domain. Their strong correlation suggests periods of enhanced rainfall and runoff during Azolla blooms, possibly associated with increased summer season length and insolation during obliquity maxima. Cycles in the angiosperm pollen record are in anti-phase with the Azolla cycles. We interpret this pattern as edaphically drier conditions on land and reduced associated runoff during Azolla lows, possibly corresponding to obliquity minima. The precession signal is distinctly weaker than that for obliquity, and is mainly detectable in the cold-temperate Larix and bisaccate conifer pollen abundances, which is interpreted as a response to

Determination of The Adaptation of Some Azolla (Azolla anabaena L) Genotypes to The Mediterranean and Aegean Coastline Ecological Conditions

OpenAIRE

GEVREK, Mithat Nuri

2015-01-01

u çalışmada bazı azolla (Azolla anabaena L.) genotiplerinin Akdeniz-Ege kıyı kuşağına adaptasyonunun belirlenmesi amaçlanmıştır. Araştırma 20022003 ve 2003-2004 yıllarında Ege Üniversitesi Ziraat Fakültesi’nin Menemen

Studies on Using Azolla for O2-Supplementation and Its Test

Science.gov (United States)

Liu, C.-C.; Liu, X.-S.; Chen, M.; Bian, Z.-L.

Establishment of Controlling Ecological Life Safety System (CELSS) is a key technical part in the study on manned station. In order to meet the requirement of long-term out-earth man-carrying flight, it is necessary to build plant-based O2-supplying CELSS. It also possesses the possibility to contribute the realization of mankind dream to live in out-earth planets. Using the physiological reaction of organisms, this system settled the problem in food supply, O2 and water recycle, the regeneration and utilization of CO2 and life residues, thus guarantee the spacemen the health, safety and efficient work when they are far from earth and arrived the space where human is difficult to life in. Azolla as a plant that possesses high growing speed, short growing cycle, high photosynthesis and O2-releasing capacity, and can be artificially grow in multi-layer facilities, it is hopeful to be an important biological part in CELSS for it's the function in O2 production and to be a part of fresh vegetable as well as CO2 absorption. This paper described the study in Azolla as a plant for supplementary O2 supply in future space station flight. The "Azolla-dog" controlling tight system was firstly established in order to determine the regulation of O2-CO2 variation and balance using different weights of dogs with different Azolla growing areas. The further studies included the development of air-tight cabinets where "Azolla-human" airtight experiments were conducted, and the relationship between Azolla-growing area and O2 requirement by human was analyzed. Based on these works, the further experiment on supplementary O2-supply of Azolla-human system was conducted in demonstration cabin for environmental controlling and life security. The O2-supplying amount of Azolla was further gained, and it will provide the experimental basis to probe optimum condition to grow Azolla in space and human-machine combining experiment, also to lay a basis for Azolla as a biological part to enter

Phytoremediation potential of aquatic macrophyte, Azolla.

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Sood, Anjuli; Uniyal, Perm L; Prasanna, Radha; Ahluwalia, Amrik S

2012-03-01

Aquatic macrophytes play an important role in the structural and functional aspects of aquatic ecosystems by altering water movement regimes, providing shelter to fish and aquatic invertebrates, serving as a food source, and altering water quality by regulating oxygen balance, nutrient cycles, and accumulating heavy metals. The ability to hyperaccumulate heavy metals makes them interesting research candidates, especially for the treatment of industrial effluents and sewage waste water. The use of aquatic macrophytes, such as Azolla with hyper accumulating ability is known to be an environmentally friendly option to restore polluted aquatic resources. The present review highlights the phytoaccumulation potential of macrophytes with emphasis on utilization of Azolla as a promising candidate for phytoremediation. The impact of uptake of heavy metals on morphology and metabolic processes of Azolla has also been discussed for a better understanding and utilization of this symbiotic association in the field of phytoremediation.

Aquatic microphylla Azolla: a perspective paradigm for sustainable agriculture, environment and global climate change.

Science.gov (United States)

Kollah, Bharati; Patra, Ashok Kumar; Mohanty, Santosh Ranjan

2016-03-01

This review addresses the perspectives of Azolla as a multifaceted aquatic resource to ensure ecosystem sustainability. Nitrogen fixing potential of cyanobacterial symbiont varies between 30 and 60 kg N ha(-1) which designates Azolla as an important biological N source for agriculture and animal industry. Azolla exhibits high bioremediation potential for Cd, Cr, Cu, and Zn. Azolla mitigates greenhouse gas emission from agriculture. In flooded rice ecosystem, Azolla dual cropping decreased CH4 emission by 40 % than did urea alone and also stimulated CH4 oxidation. This review highlighted integrated approach using Azolla that offers enormous public health, environmental, and cost benefits.

Climatic conditions governing extensive Azolla bloom during the Middle Eocene

Science.gov (United States)

Dekker, Rolande; Speelman, Eveline N.; Barke, Judith; Konijnendijk, Tiuri; Sinninge Damste, Jaap S.; Reichart, Gert-Jan

2010-05-01

Enormous amounts of intact mega- and microspores from the free floating aquatic fern Azolla were found in sediments recovered during Integrated Ocean Drilling Program expedition 302, indicating that Azolla grew and reproduced in situ in the Eocene Arctic Ocean. In general, the Early/Middle Eocene is characterized by enhanced greenhouse conditions with elevated sea surface temperatures (SSTs) in the Arctic (~10°C), while tropical sea surface temperatures (SSTs) were only a little warmer than today (with a mean annual temperature (MAT) of 32-34 °C) (Pearson et al., 2007). The consequently reduced temperature gradient between the equator and the poles and the presence of freshwater at the North Pole as indicated by the presence of the freshwater fern Azolla (Brinkhuis et al., 2006) provide important boundary conditions for understanding the hydrological cycle and latent heat transport during this interval. Here we reconstruct variations in SST and mean annual air temperature using the TEX86 and MBT temperature proxies for the Azolla interval. Sediments from around the Arctic Basin have been analyzed, including samples from Alaska, the Mackenzie Basin, Greenland (IODP core 913b), and Denmark. Furthermore, a high resolution sea surface temperature record for the Azolla interval has been constructed from sediment samples from the Lomonosov Ridge, showing a cyclic signal. Model experiments have shown that the here confirmed low equator-to-pole temperature gradient modulated the hydrological cycle. Since the growth of Azolla is restricted to low salinity conditions, changes in the hydrological cycle are proposed to coincide with the cyclic occurrence of Azolla throughout the interval. To confirm the overlapping presence of high quantities of Azolla and increased precipitation, changes in the hydrogen cycle are reconstructed by creating a high resolution hydrogen isotope record throughout the interval. By performing compound specific analyses (δD) on terrestrial derived

CHANGES IN SOIL CHEMICAL PROPERTIES OF ORGANIC PADDY FIELD WITH AZOLLA APPLICATION

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Jauhari Syamsiyah

2016-12-01

Full Text Available The use of organic fertilizer is a way to improve soil fertility. Azolla can be used as organic fertilizer. This study aims to determine the effect of Azolla (Azolla mycrophylla. L on some soil chemical properties on organic paddy field. The field experiments used factorial complete randomized block design of three factors, namely Azolla (0 and 2 tons/ha, Manure (0 and 10 tons/ha and Rice Varieties (Mira1, Mentik Wangi and Merah Putih, with three times replication. Using Azolla on an organic paddy field does not significantly increase the levels of soil N, organic C, Cation Exchange Capacity and soil pH. However Azolla’s influence on soil available P is significant.

Influence of azolla on rice growth treated with and without N fertilizer

International Nuclear Information System (INIS)

Sisworo, E.L.; Sisworo, W.H.; Hendratno; Rasyid, H.; Solahuddin, S.; Partohardjono, S.

1987-01-01

Influence of azolla on rice growth treated with and without fertilizer. An experiment to investigate the influence of azolla on growth of rice treated with and without N fertilizer has been carried out in the rainy season 1984/1985 at the Muara Experimental Station, Bogota. Rice variety used in this experiment was Atomita I. Eight treatments employed in this experiment were treatments without azolla and N fertilizer, with azolla alone, with N fertilizer alone, and a combination of azolla and N fertilizer used was urea labelled with 5% 15 N atom excess. Parameters observed were: dry weight, total-N and N-derived from fertilizer in rough grain, straw and plant. Data from this experiment indicated that azolla was able to produce similar yield of rough grain, straw and plant with those produced by N fertilizer applied at a rate of 90 kg N/ha. These data were much higher compared to N fertilizer applied at a rate of 30 and 60 kg N/ha. The same trend was found in yield of N. It turned out that apparently azolla is effective to increase rice production. (author). 3 figs., 8 refs

Response of growth and antioxidant enzymes in Azolla plants (Azolla pinnata and Azolla filiculoides) exposed to UV-B.

Science.gov (United States)

Masood, Amjad; Zeeshan, M; Abraham, G

2008-06-01

Effect of ultravilolet-B (0.4 Wm(-2)) irradiation on growth, flavonoid content, lipid peroxidation, proline accumulation and activities of superoxide dismutase and peroxidase was comparatively analysed in Azolla pinnata and Azolla filiculoides. Growth measured as increment in dry weight reduced considerably due to all UV-B treatments. However, the reduction was found to be severe in A. filiculoides as compared to A. pinnata. The level of UV-absorbing compound flavonoids increased significantly in A. pinnata plants whereas only a slight increase in the flavonoid content was observed in A. filiculoides. UV-B exposure led to enhanced production of malondialdehyde (MDA) and electrolyte leakage in A. filiculoides than A. pinnata. Proline accumulation also showed a similar trend. Marked differences in the activity of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD) was noticed in both the plants exposed to UV-B. Our comparative studies indicate A. pinnata to be better tolerant to UV-B as compared with A. filiculoides which appears to be sensitive.

Phytochemical characterization of the threatened specie Fraxinus caroliniana Mill subsp. cubensis (Griseb. Borhidi

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Mabelkis Terry Rosabal

2016-04-01

Full Text Available Fraxinus caroliniana Mill subsp. cubensis (Griseb. Borhidi is commonly known as buffalo, represents an endemic subspecies and categorized as critical danger of extinction in Cuba. This work aimed to characterize the phytochemical composition of plants of F. caroliniana in two localities of the Matanzas province. The presence of secondary metabolites in leaf extracts was qualitatively analyzed and reductive and total sugars were quantified. The results indicated the presence of flavonoids, terpenes, steroids, saponins, tannins and anthraquinones in leaves that could be considered for further systematic studies and application in agriculture. The plants from the Ciénaga de Zapata showed contents of reducing sugars and totals higher than those obtained in the plants of Martí. These results provide information for the identification of characters of possible taxonomic and conservation value in this species.   Keywords: anthraquinons, extracts, swamp ash, steroids, tannins, terpens

Fertilizer effect Azolla - Anabaena in maize (Zea mays L.

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Aldás-Jarrín Juan Carlos

2016-11-01

Full Text Available The deterioration of natural resources in agricultural activities, has motivated the search for new alternatives to enrich the soil with macro and micro nutrients sustainably, for the benefit of future generations, just as you think about the conservation and maintenance of water, avoiding eutrophication problems by the accumulation of fertilizers (nitrates and nitrites leached and deposited in natural sources, for this purpose they have been measured several agro ecological options that provide proper nutrition and a delicate ecological balance; in this investigation at field level in maize cultivation and different states it applied dose of azolla as a natural source of nitrogen to enrich the soil in the canton Cevallos, Tungurahua province. Anabaena floors of the town, based on the state of azolla and the level established for such preparation, the states of azolla. Six mixtures were prepared substrates azolla studied were: Dry A1 and A2 in the fresh state; the doses were established in relation to the volume of azolla against soil volume used: (0.5: 1 (0.75: 1 and (1: 1. The data collected were plant height and percentage of nitrogen in dry matter at 15, 30, 60 and 90 days. All this in order to establish the amount of nitrogen contributed by azolla as biofertilizer in growing corn. The best results were presented at the A1D3 (azolla dry-Dose 1: 1 treatment given plant height 15.02 cm at 15 days, 35.88 cm 30 days, 53.22 cm 60 66.12 days and 90 days; to 0.54% nitrogen percentage at 15 days, 0.90% at 30 days, 1.68% at 60 days and 2.08% after 90 days. In conclusion, the use of Azolla as a bio-fertilizer rich in nitrogen is feasible, as has been demonstrated in this research that the corn plant benefits from the contribution of this material, improving sustainable agricultural practices. It is recommended to expand this research in the same crop or other commercially important crops until the end of its production cycle, to report the results of

Population Dynamics of Biota on the Roots of Azolla microphylla Kaulfuss

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NITA ETIKAWATI

2000-01-01

Full Text Available Azolla was a special fern that their associations with Anabaena azollae able to fix free nitrogen from air, to produce protein. Although by the ages, biota diversity those habits on the roots of Azolla increased and effected to protein concentration. The research was to find out population dynamics of biota on the roots of Azolla microphylla Kaulfuss and the growth peak. This study used Completely Randomized Design with 10 kinds of biota, i.e. bacteria, Fungi, Actinomycetes, Protozoa, Alga, Crustacean, Rotifers, Coelenterate, Insect and Molluscs, and it was used 3 replications. Research was conducted within 4 weeks and the populations of biota were observed every week. Data were statistically analyzed using Analysis Variant and Duncan’s Multiple Range Test. The population dynamics of biota on the roots of Azolla microphylla Kaulfuss were influenced on its quantity and composition, and the growth peak is done in 2nd week.

Azolla-Anabaena Relationship

Science.gov (United States)

Ray, Thomas B.; Mayne, Berger C.; Toia, Robert E.; Peters, Gerald A.

1979-01-01

Photosynthesis in the Azolla-Anabaena association was characterized with respect to photorespiration, early products of photosynthesis, and action spectra. Photorespiration as evidenced by an O2 inhibition of photosynthesis and an O2-dependent CO2 compensation concentration was found to occur in the association, and endophyte-free fronds, but not in the endophytic Anabaena. Analysis of the early products of photosynthesis indicated that both the fern and cyanobacterium fix CO2 via the Calvin cycle. The isolated endophytic Anabaena did not release significant amounts of amino acids synthesized from recently fixed carbon. The action spectra for photosynthesis in the Azolla-Anabaena association indicated that the maximum quantum yield is between 650 and 670 nanometers, while in the endophyte the maximum is between 580 and 640 nanometers. Although the endophytic cyanobacterium is photosynthetically competent, any contribution it makes to photosynthesis in the intact association was not apparent in the action spectrum. PMID:16661055

Pig-duck-fish-azolla integration in La Union, Philippines

OpenAIRE

Gavina, L.D.

1994-01-01

Three studies on pig-duck-fish-azolla integration were conducted simultaneously in La Union, Philippines. Growth performance of pigs and ducks as affected by different levels of azolla meal in their feed, and that of tilapia (Oreochromis niloticus) under varying stocking rates are presented and discussed.

Azolla filiculoides Nitrogenase Activity Decrease Induced by Inoculation with Chlamydomonas sp. †

Science.gov (United States)

Habte, Mitiku

1986-01-01

Experiments were conducted to determine the influence of Chlamydomonas sp. on nitrogen fixation (C2H2 → C2H4) in Azolla filiculoides and on the nitrogen fixation and growth of free-living Anabaena azollae 2B organisms. Inoculation of azolla medium with Chlamydomonas sp. was associated with decreased nitrogenase activity in A. filiculoides and with increases in the density of a fungal population identified as Acremonium sp. Subsequent inoculation of azolla medium with this fungus was also accompanied by a significant decrease in nitrogenase activity of A. filiculoides. However, the extent of depression of nitrogenase activity was significantly higher when azolla medium was inoculated with Chlamydomonas sp. than when it was inoculated with Acremonium sp. Inoculation of nitrogen-free Stanier medium with either Acremonium sp. or Chlamydomonas sp. did not adversely affect the growth or nitrogenase activity of free-living A. azollae. Decreased nitrogenase activity in A. filiculoides is apparently related to the adverse influence of the green alga and the fungus on the macrosymbiont. The mechanisms that might be involved are discussed. PMID:16347211

Efficacy of oxygen-supplying capacity of Azolla in a controlled life support system

Science.gov (United States)

Chen, Min; Deng, Sufang; Yang, Youquan; Huang, Yibing; Liu, Chongchu

2012-02-01

Azolla shows high growth and propagation rates, strong photosynthetic O2-releasing ability and high nutritional value. It is suitable as a salad vegetable and can be cultured on a multi-layered wet bed. Hence, it possesses potential as a fresh vegetable, and to release O2 and absorb CO2 in a Controlled Ecological Life Support System in space. In this study, we investigated the O2-providing characteristics of Azolla in a closed chamber under manned, controlled conditions to lay a foundation for use of Azolla as a biological component in ground simulation experiments for space applications. A closed test chamber, representing a Controlled Ecological Life Support System including an Azolla wet-culture device, was built to measure the changes in atmospheric O2 and CO2 concentrations inside the chamber in the presence of coexisting Azolla, fish and men. The amount of O2 consumed by fish was 0.0805-0.0831 L kg-1 h-1 and the level of CO2 emission was 0.0705-0.0736 L kg-1 h-1; O2 consumption by the two trial volunteers was 19.71 L h-1 and the volume of respiration-released CO2 was 18.90 L h-1. Under 7000-8000 Lx artificial light and Azolla wet-culture conditions, human and fish respiration and Azolla photosynthesis were complementary, thus the atmospheric O2 and CO2 concentrations inside chamber were maintained in equilibrium. The increase in atmospheric CO2 concentration in the closed chamber enhanced the net photosynthesis efficiency of the Azolla colony. This study showed that Azolla has strong photosynthetic O2-releasing ability, which equilibrates the O2 and CO2 concentrations inside the chamber in favor of human survival and verifies the potential of Azolla for space applications.

Understanding nutrient exchange between Azolla and its symbiont, Nostoc

OpenAIRE

Eily, Ariana

2017-01-01

This is an in-depth look at the research I am doing for my doctoral degree at Duke University, investigating the exchange of nutrients between the aquatic fern genus, Azolla, and its cyanobacterial symbiont, Nostoc azollae. All of the illustrations and microscopy images within this presentation are my own.

Growth and cellular ion content of a salt-sensitive symbiotic system Azolla pinnata-Anabaena azollae under NaCl stress.

Science.gov (United States)

Rai, Vandna; Sharma, Naveen Kumar; Rai, Ashwani K

2006-09-01

Salinity, at a concentration of 10 mM NaCl affected the growth of Azolla pinnata-Anabaena azollae association and became lethal at 40 mM. Plants exposed up to 30 mM NaCl exhibited longer roots than the control, especially during the beginning of incubation. Average root number in plants exposed to 10 and 20 mM NaCl remained almost the same as in control. A further rise in NaCl concentration to 30 mM reduced the root number, and roots shed off at 40 mM NaCl. Presence of NaCl in the nutrient solution increased the cellular Na+ of the intact association exhibiting differential accumulation by individual partners, while it reduced the cellular Ca2+ level. However, cellular K+ content did not show significant change. Cellular Na+ based on fresh weight of respective individual partners (host tissues and cyanobiont) remained higher in the host tissues than the cyanobiont, while reverse was true for K+ and Ca2+ contents. The contribution of A. azollae in the total cellular ion content of the association was a little because of meagre contribution of the cyanobiont mass (19-21%). High salt sensitivity of Azolla-Anabaena complex is due to an inability of the association to maintain low Na+ and high Ca2+ cellular level.

Effect of inoculating blue-green algae and Azolla on rice yield

International Nuclear Information System (INIS)

Kulasooriya, S.A.

1985-01-01

Nitrogen fixing blue-green algae (BGA) and the Azolla-Anaebaena symbiosis are potential alternative sources of nitrogen for lowland rice production. A survey of the literature shows that on the average, when BGA inoculation is effective, a rice yield increase of 14% (450 kg grain ha -1 ) has been observed. However, in Sri Lanka no significant increases in grain yield have been observed due to BGA inoculation. Azolla inoculation in broadcast, transplanted, and avenue transplanted rice gave yield increases of 12, 22 and 48%, and was equivalent to 55 to 80 kg N ha -1 as urea. Azolla was observed to reduce weed growth by 53%. Azolla is easier to establish in rice fields since it can be easily recognized with the naked eye, however, BGA are better able to withstand periods of desiccation which occur in rain-fed rice production. Most algalization experiments have been performed on a ''black box'' basis where only the final grain yield has been measured. Isotope experiments can play a vital role in understanding the processes by which BGA and Azolla increase rice yields. (author)

Localization and toxic effects of cadmium, copper, and uranium in Azolla

International Nuclear Information System (INIS)

Sela, M.; Tel-Or, E.; Fritz, E.; Huttermann, A.

1988-01-01

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis. The relative content of copper was eightfold higher in the root than in the shoot, suggesting low mobility of this metal in Azolla plant. Cadmium relative content in the shoot was similar to its content in the root, hence its mobility was relatively high. The absence of significant uranium quantities in the shoot and its relative high content in the root suggest the immobility of this metal from Azolla root. Cadmium formed precipitates with phosphate and calcium in xylem cells of the shoot bundle and caused a two- to threefold increase in the content of phosphate in the root. Uranium in roots and cadmium in shoots were associated with calcium. All three treatments caused losses of potassium, chloride, and magnesium from Azolla roots. Accumulation of heavy metals in Azolla and their mobility from the root to the shoot can be correlated with damage caused by the loss of essential nutrients

Localization and toxic effects of cadmium, copper, and uranium in azolla.

Science.gov (United States)

Sela, M; Tel-Or, E; Fritz, E; Huttermann, A

1988-09-01

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis. The relative content of copper was eightfold higher in the root than in the shoot, suggesting low mobility of this metal in Azolla plant. Cadmium relative content in the shoot was similar to its content in the root, hence its mobility was relatively high. The absence of significant uranium quantities in the shoot and its relative high content in the root suggest the immobility of this metal from Azolla root. Cadmium formed precipitates with phosphate and calcium in xylem cells of the shoot bundle and caused a two- to threefold increase in the content of phosphate in the root. Uranium in roots and cadmium in shoots were associated with calcium. All three treatments caused losses of potassium, chloride, and magnesium from Azolla roots. Accumulation of heavy metals in Azolla and their mobility from the root to the shoot can be correlated with damage caused by the loss of essential nutrients.

Pengaruh Pemberian Berbagai Bentuk Azolla Dan Pupuk N Terhadap Pertumbuhan Dan Hasil Tanaman Jagung Manis (Zea Mays Var. Saccharata)

OpenAIRE

Putra, Dwi Firmansyah; Soenaryo, Soenaryo; Tyasmoro, Setyono Yudo

2013-01-01

Jagung manis sangat responsif terhadap pupuk N, agar kebutuhan N terpenuhi dan memberikan nilai tambah dapat menyuburkan tanah tanpa menurunkan produktifitas jagung manis, maka diperlukan penyeimbang berupa pupuk organik yang memiliki kandungan N tinggi. Pupuk organik potensial yang memiliki kandungan N tinggi yaitu Azolla. Azolla dapat ditemukan dalam 3 bentuk yaitu Azolla segar, Azolla kering dan kompos Azolla. Penelitian ini bertujuan untuk mengetahui pengaruh aplikasi Azolla segar, Azolla...

The potential of the fresh-water fern Azolla in aquatic farming systems

Science.gov (United States)

Bijl, Peter K.; Werf, vd, Adrie; Schluepmann, Henriette; Reichart, Gert-Jan; Brouwer, Paul; Nierop, Klaas G. J.; Hellgardt, Klaus; Brinkhuis, Henk

2014-05-01

With aquatic farming systems a new avenue in agriculture is explored, in which the competition with conventional arable land is avoided. The aquatic, ubiquitous, floating fern Azolla is not yet widely explored as potential crop in such farming systems, despite its high potential because it grows in many natural systems under low-light intensities, has an enormous annual yield, and has special biomass qualities for applications in food, feed and specialty chemical industries. But, what makes Azolla particularly interesting as cost-effective crop is its capability to take up atmospheric nitrogen through symbiosis with nitrogen-fixing bacteria Anabaena azollae. This makes Azolla independent of nitrogen fertilization. In order to explore the potential of Azolla as a crop for a suite of applications, we have assembled a team of expertise: AZOFAST, consisting of agricultural engineers, plant physiologists, chemical engineers and organic chemists. Our growth experiments reveal high annual production yields with constant harvest. We are developing a germination and spore collecting/preservation protocol as a first step to domestication. Finally we have explored the biomass quality of different species of extant Azolla. We performed organic chemical analyses on lipid and tannin extracts, and quantified yields of specific compounds within these fractions. In our presentation we will present some of our results to show the potential of Azolla as a new, sustainable aquatic crop serving all kinds of industrial streams from protein feed to platform chemicals.

Study on O2-supplying characteristics of Azolla in Controlled Ecological Life Support System

Science.gov (United States)

Chen, Min; Deng, Sufang; Yang, Youquang; Huang, Yibing; Liu, Zhongzhu

Azolla has high growth and propagation rate, strong photosynthetic O2-releasing ability and rich nutrient value. It is able to be used as salad-type vegetable, and can also be cultured on wet bed in multi-layer condition. Hence, it possesses a potential functioning as providing O2, fresh vegetable and absorbing CO2 for Controlled Ecological Life Support System in space. In this study, we try to make clear the O2-providing characteristics of Azolla in controlled close chamber under manned condition in order to lay a foundation for Azolla as a biological component in the next ground simulated experiment and space application. A closed test cham-ber of Controlled Ecological Life Support System and Azolla wet-culturing devices were built to measure the changes of atmospheric O2-CO2 concentration inside chamber under "Azolla-fish -men" coexisting condition. The results showed that, the amount of O2 consumption is 80.49 83.07 ml/h per kilogram fish, the amount of CO2 emissions is 70.49 73.56 ml/(kg • h); O2 consumption of trial volunteers is 19.71 L/h, the volume of respiration release CO2 18.90 L/h .Artificial light intensity of Azolla wet culture under 70009000 Lx, people respiration and Azolla photosynthesis complemented each other, the atmospheric O2-CO2 concentration inside chamber maintained equilibration. Elevated atmospheric CO2 concentrations in close chamber have obvious effects on enhancing Azolla net photosynthesis efficiency. This shows that Azolla has strong photosynthetic O2-releasing ability, which equilibrates the O2-CO2 concentration inside chamber in favor of human survival, and then verifies the prospect of Azolla in space application.

The freshwater fern Azolla (Azollaceae) from Eocene Arctic and Nordic Sea sediments: New species and their stratigraphic distribution

NARCIS (Netherlands)

van der Burgh, J.; Collinson, M.E.; van Konijnenburg-van Cittert, J.H.A.; Barke, J.; Brinkhuis, H.

2013-01-01

Three new species of the freshwater fern Azolla are described from Eocene marine deposits of the Arctic and Nordic seas, bringing the total number of species now documented from these areas to five. Azolla arctica Collinson et al., Azolla jutlandica Collinson et al., Azolla nova sp. nov. and Azolla

Agricultural production - Phase 2. Indonesia. Rice - azolla - fish culture - use of nuclear technique

International Nuclear Information System (INIS)

Watanabe, Iwao.

1991-01-01

The primary aim of the expert mission was to provide advice on the use of nuclear techniques to study rice-azolla-fish culture. Results of the work performed so far show that basal application of azolla gives similar or better yields of rice than basal application of urea. Fish productivity was also found to be significantly higher when azolla is present. 2 tabs

Pengaruh Biomassa Azolla Terhadap Status Logam Berat Timbal (Pb) Pada Tanah

OpenAIRE

Abror, Muhammad; Sabrina, Teuku; Hidayat, Benny

2013-01-01

Research on title the effect of Pb-Polluted azolla biomass on polluted on lead heavy metal status at polluted and unpolluted soil with Pb aimed to evaluate the potency of Pb-polluted azolla biomass on the availability of Pb in soil. The experiment design was factorial randomized block design with 2 factors and 3 replications. First factor was Pb-polluted azolla biomass with 3 treatments 0 g/kg, 15 g/kg and 30g/kg, second factor was Pb application with 3 treatments 0 ppm/kg, 150 ppm/kg, and 3...

Micro-halocline enabled nutrient recycling may explain extreme Azolla event in the Eocene Arctic Ocean.

Science.gov (United States)

van Kempen, Monique M L; Smolders, Alfons J P; Lamers, Leon P M; Roelofs, Jan G M

2012-01-01

In order to understand the physicochemical mechanisms that could explain the massive growth of Azolla arctica in the Eocene Arctic Ocean, we carried out a laboratory experiment in which we studied the interacting effects of rain and wind on the development of salinity stratification, both in the presence and in the absence of a dense Azolla cover. Additionally, we carried out a mesocosm experiment to get a better understanding of the nutrient cycling within and beneath a dense Azolla cover in both freshwater and brackish water environments. Here we show that Azolla is able to create a windproof, small-scale salinity gradient in brackish waters, which allows for efficient recycling of nutrients. We suggest that this mechanism ensures the maintenance of a large standing biomass in which additional input of nutrients ultimately result in a further expansion of an Azolla cover. As such, it may not only explain the extent of the Azolla event during the Eocene, but also the absence of intact vegetative Azolla remains and the relatively low burial efficiency of organic carbon during this interval.

Micro-halocline enabled nutrient recycling may explain extreme Azolla event in the Eocene Arctic Ocean.

Directory of Open Access Journals (Sweden)

Monique M L van Kempen

Full Text Available In order to understand the physicochemical mechanisms that could explain the massive growth of Azolla arctica in the Eocene Arctic Ocean, we carried out a laboratory experiment in which we studied the interacting effects of rain and wind on the development of salinity stratification, both in the presence and in the absence of a dense Azolla cover. Additionally, we carried out a mesocosm experiment to get a better understanding of the nutrient cycling within and beneath a dense Azolla cover in both freshwater and brackish water environments. Here we show that Azolla is able to create a windproof, small-scale salinity gradient in brackish waters, which allows for efficient recycling of nutrients. We suggest that this mechanism ensures the maintenance of a large standing biomass in which additional input of nutrients ultimately result in a further expansion of an Azolla cover. As such, it may not only explain the extent of the Azolla event during the Eocene, but also the absence of intact vegetative Azolla remains and the relatively low burial efficiency of organic carbon during this interval.

Microcosm investigation on phytoremediation of Cr using Azolla pinnata.

Science.gov (United States)

Rai, Prabhat Kumar

2010-01-01

The extent of Chromium (Cr) pollution in Singrauli industrial region, India was assessed and phytoremediation capacity of a small water fern, Azolla pinnata R.BR (Azollaceae) was observed to purify waters polluted by Cr under microcosm condition. Azolla pinnata endemic to India is a potential hyper-accumulator of heavy metals. During 13 days of the experiment the fern was grown in the aqueous medium containing Cr3+ and CrO4(2-) ions, each in a concentration 0.5, 1.0, and 3.0 mg L(-1). The presence of these ions caused a + 3.1 to -37.5% inhibition of Azolla pinnata growth in comparison to the control. After 13 days of the experiment, metal contents in the solution was decreased up to 70% (CrO4(2-) 3.0 mg L(-1) treatment) to 88% (CrO4(2-) 0.5 mg L(-1) treatment). In the Azolla pinnata tissues, the concentration of couple of the ionic forms of Cr under investigation ranged from 415 to 1095 mg kg(-1) dry mass (dm); the highest level being found for Cr (III) containing solution.

Pengaruh Beberapa Dosis Kompos Dan Azolla ( Azolla Pinnata R. B ) Segar Pada Pertumbuhan Dan Hasil 2 Varietas Tanaman Wortel ( Daucus Carotta L. )

OpenAIRE

Huda, M. Syahrial; Widaryanto, Eko; Nugroho, Agung

2016-01-01

Wortel termasuk jenis sayuran umbi yang bernilai ekonomis penting di dunia. Salah satu factor budidaya wortel adalah tanah yang tidak hanya sebagai media akar tanaman namun sebagai media tanaman dapat menyerap nutrisi, air dan oksigen. Salah satu peranan bahan organik adalah memperbaiki sifat fisik tanah. Azolla (Azolla pinnata) ialah tumbuhan paku air yang dapat dimanfaatkan sebagai bahan organik untuk memperbaiki agregat tanah. Tujuan penelitian ini untuk dapat mengetahui pengaruh dosis kom...

The optimum energy harvest efficiency of nitrogen fixing hydrophyte: Azolla pinnata

Energy Technology Data Exchange (ETDEWEB)

Tennakone, K. (Institute of Fundamental Studies, Kandy (LK) Ruhuna Univ., Matara (LK). Dept. of Physics); Punchihewa, S.; Jayasuriya, A.C. (Institute of Fundamental Studies, Kandy (LK))

1989-01-01

Azolla is a nitrogen fixing hydrophyte that can be cultivated in absence of nitrogenous fertilizer. It is found that when biomass is continuously harvested from a culture of Azolla, solar energy can be converted at an optimum efficiency of 1.1%. (author).

Effects of atmospheric SO[sub 2] on Azolla and Anabaena symbiosis

Energy Technology Data Exchange (ETDEWEB)

Hur, J.-S.; Wellburn, A.R. (Division of Biological Sciences, Institute of Environmental and Biological Sciences, Lancaster Univ., Lancaster (United Kingdom))

1993-01-01

The water fern Azolla pinnata R. Br. was fumigated for 1 week with either 25, 50 or 100 nl l[sup -1] SO[sub 2]. The symbiosis of Azolla with Anabaena azollae (spp.) was severely damaged by atmospheric SO[sub 2] even at the lowest concentration studied showing significant reductions in growth, reduction of C[sub 2]H[sub 2], NH[sub 3] assimilation, protein synthesis, and heterocyst development. These disturbances appear to be mainly responsible for the extreme sensitivity of this fern to atmospheric SO[sub 2]. Changes in violaxanthin/antheraxanthin and epoxylutein/lutein ratios also indicate that free radical products are induced by atmospheric SO[sub 2]. These results suggest that the Azolla-Anabeana symbiotic system is a very responsive and reliable lower plant model to study the detailed effects of total sulfur deposition upon the balances between various important plant metabolic processes.

Protection against salt toxicity in Azolla pinnata-Anabaena azollae symbiotic association by using combined-N sources.

Science.gov (United States)

Mishra, A K; Singh, Satya S

2006-09-01

Protection from salt stress was observed in the terms of yield (fresh and dry weight, chlorophyll and protein) and nitrogenase activity. Azollapinnata appeared highly sensitive to 40 mM external NaCl stress. Fronds of Azolla unable to grow beyond a concentration of 30 mM NaCl and accordingly death was recorded at 40 mM NaCl on the 6th day of incubation. Yield was inhibited by various levels of NaCl (0, 10, 20 and 30 mM). Addition of combined-N to the growth medium protected the association partially from salt toxicity. Among the N-sources (NO3-, NH4+ and urea) tried, urea mitigated the salt-induced toxicity most efficiently. Reduction in nitrogenase activity was observed when intact Azolla was grown in nutrient medium either supplemented with different levels of NaCl or combined nitrogen. Only NO3- (5 mM) protected the enzymatic activity from salt toxicity while other concentrations of ammonium, nitrate and urea slowed down the salt-induced inhibition of enzyme activity in Azolla-Anabaena association. These results suggested that an optimum protection from salt stress could be obtained by using a combination of combined nitrogen sources. The reason for this protection might be due to the availability of combined nitrogen to the association, nitrogen is only available through the biological nitrogen fixation which is the most sensitive to salt stress.

Jasmonic and salicylic acid response in the fern Azolla filiculoides and its cyanobiont.

Science.gov (United States)

de Vries, Sophie; de Vries, Jan; Teschke, Hendrik; von Dahlen, Janina K; Rose, Laura E; Gould, Sven B

2018-01-03

Plants sense and respond to microbes utilizing a multilayered signalling cascade. In seed plants, the phytohormones jasmonic and salicylic acid (JA and SA) are key denominators of how plants respond to certain microbes. Their interplay is especially well-known for tipping the scales in plants' strategies of dealing with phytopathogens. In non-angiosperm lineages, the interplay is less well understood, but current data indicate that it is intertwined to a lesser extent and the canonical JA/SA antagonism appears to be absent. Here, we used the water fern Azolla filiculoides to gain insights into the fern's JA/SA signalling and the molecular communication with its unique nitrogen fixing cyanobiont Nostoc azollae, which the fern inherits both during sexual and vegetative reproduction. By mining large-scale sequencing data, we demonstrate that Azolla has most of the genetic repertoire to produce and sense JA and SA. Using qRT-PCR on the identified biosynthesis and signalling marker genes, we show that Azolla is responsive to exogenously applied SA. Furthermore, exogenous SA application influenced the abundance and gene expression of Azolla's cyanobiont. Our data provide a framework for JA/SA signalling in ferns and suggest that SA might be involved in Azolla's communication with its vertically inherited cyanobiont. © 2018 John Wiley & Sons Ltd.

Metabolic adaptation, a specialized leaf organ structure and vascular responses to diurnal N2 fixation by nostoc azollae sustain the astonishing productivity of azolla ferns without nitrogen fertilizer

NARCIS (Netherlands)

Brouwer, Paul; Bräutigam, Andrea; Buijs, Valerie A.; Tazelaar, Anne O.E.; van der Werf, Adrie; Schlüter, Urte; Reichart, Gert-Jan; Bolger, Anthony; Usadel, Björn; Weber, Andreas P.M.; Schluepmann, Henriette

2017-01-01

Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf

The pore of the leaf cavity of Azolla species: teat cell differentiation and cell wall projections.

Science.gov (United States)

Veys, P; Lejeune, A; Van Hove, C

2002-02-01

The differentiation of the specialized secretory teat cells of the leaf cavity pore of Azolla species was investigated at the ultrastructural level with emphasis on their peculiar cell wall projections. The results indicated that the projections are formed as soon as the teat cells complete their differentiation and that their production is principally associated with changes in endoplasmic reticulum profiles. The number of projections increases with the teat cell age and is stimulated under salt and P deficiency stresses. Salt stress also promotes their emergence on Azolla species that under normal conditions do not produce projections. Cytochemical tests on different Azolla species showed that the projection composition is almost identical: proteins, acidic polysaccharides, and pectin are always detected. This study revealed that Azolla teat cell projections differ fundamentally from other types of hitherto described cell wall projections that are considered as remnant structures from cell separation. In contrast, in Azolla teat cells projections are actively produced and compounds are excreted by an exocytotic mechanism. The possible role of the projections in the symbiosis of Azolla spp. with Anabaena azollae is discussed.

Localization and Toxic Effects of Cadmium, Copper, and Uranium in Azolla1

Science.gov (United States)

Sela, Mordechai; Tel-Or, Elisha; Fritz, Eberhardt; Huttermann, Aloys

1988-01-01

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis. The relative content of copper was eightfold higher in the root than in the shoot, suggesting low mobility of this metal in Azolla plant. Cadmium relative content in the shoot was similar to its content in the root, hence its mobility was relatively high. The absence of significant uranium quantities in the shoot and its relative high content in the root suggest the immobility of this metal from Azolla root. Cadmium formed precipitates with phosphate and calcium in xylem cells of the shoot bundle and caused a two- to threefold increase in the content of phosphate in the root. Uranium in roots and cadmium in shoots were associated with calcium. All three treatments caused losses of potassium, chloride, and magnesium from Azolla roots. Accumulation of heavy metals in Azolla and their mobility from the root to the shoot can be correlated with damage caused by the loss of essential nutrients. Images Fig. 1 Fig. 2 Fig. 5 Fig. 7 PMID:16666274

Biosorption of uranium by Azolla, SP, Brazil

International Nuclear Information System (INIS)

Vieira, Ludmila C.; Alves, Eliakim G.; Marumo, Julio T.; Ferreira, Rafael V. de P.; Canevesi, Rafael L.S.; Silva, Edson A.

2015-01-01

Radioactive liquid waste needs special attention and requires suitable treatment before deposition. Among the potential technologies under development for the treatment of liquid radioactive wastes the biosorption has been highlighted by being an efficient and low cost technique. Biosorption process involves the exchange of ions contained in the biomass matrix by others present in solution. There are many biomasses that could be applied in treatment of radioactive wastes, for example, agricultural residues and macrophyte. The aim of this study is evaluate the ability of the Azolla sp., a floating aquatic plant, to absorb uranium in solution. Azolla sp. is a macrophyte that has been used to treat effluents containing heavy metals. The biosorption capacity of uranium by Azolla sp. was experimentally determined and modeled by isotherms. Experiments were performed to determine metal uptake, and then the solutions were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The isotherms applied to model the data was Langmuir, Freundlich, Sips Toth, Redlich Peternson, Two-Site-Langmuir, Radke Prausnitz to develop a technique for the treatment of radioactive liquid waste generated at the Nuclear and Energy Research Institute (IPEN-CNEN/SP), Brazil. (author)

Biosorption of uranium by Azolla, SP, Brazil

Energy Technology Data Exchange (ETDEWEB)

Vieira, Ludmila C.; Alves, Eliakim G.; Marumo, Julio T., E-mail: lcvieira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Ferreira, Rafael V. de P., E-mail: rafael@itatijuca.com [Itatijuca Biotech, Sao Paulo, SP (Brazil); Canevesi, Rafael L.S.; Silva, Edson A., E-mail: edson.silva2@unioeste.br [Universidade Estadual do Oeste Parana (UNIOESTE), Toledo, PR (Brazil)

2015-07-01

Radioactive liquid waste needs special attention and requires suitable treatment before deposition. Among the potential technologies under development for the treatment of liquid radioactive wastes the biosorption has been highlighted by being an efficient and low cost technique. Biosorption process involves the exchange of ions contained in the biomass matrix by others present in solution. There are many biomasses that could be applied in treatment of radioactive wastes, for example, agricultural residues and macrophyte. The aim of this study is evaluate the ability of the Azolla sp., a floating aquatic plant, to absorb uranium in solution. Azolla sp. is a macrophyte that has been used to treat effluents containing heavy metals. The biosorption capacity of uranium by Azolla sp. was experimentally determined and modeled by isotherms. Experiments were performed to determine metal uptake, and then the solutions were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The isotherms applied to model the data was Langmuir, Freundlich, Sips Toth, Redlich Peternson, Two-Site-Langmuir, Radke Prausnitz to develop a technique for the treatment of radioactive liquid waste generated at the Nuclear and Energy Research Institute (IPEN-CNEN/SP), Brazil. (author)

Phytodegradation potential of bisphenolA from aqueous solution by Azolla Filiculoides.

Science.gov (United States)

Zazouli, Mohammad Ali; Mahdavi, Yousef; Bazrafshan, Edris; Balarak, Davoud

2014-01-01

Many organic hazardous pollutants such as bisphenolA (BPA) which are toxic and not easily biodegradable can concerns for environmental pollution worldwide. The objective of this study was to examine whether Azolla Filiculoides is able to remove BPA from aqueous solutions. In this study, the Azolla with different biomass (0.3, 0.6, 0.9, 1.2 g) has been cultured in solution that was contained 5, 10, 25 and 50 ppm BPA. Samples were collected every 2 days from all of containers. The analytical determination of BPA was performed by using of DR4000 uv-visible at λmax = 276 nm. The results indicated that Azolla has high ability to remove BPA from aqueous solutions. The BPA removal was 60-90%. The removal efficiency is increasing with decreasing of BPA concentration and increasing of biomass amount and vice versa. The removal efficiency was more than 90% when BPA concentration was 5 ppm and amount of biomass was 0.9gr. It is concluded that Azolla able remove BPA by Phytodegradation from the aqueous solutions. Since conventional methods of BPA removal need to high cost and energy, phytoremediation by Azolla as a natural treatment system can decrease those issues and it can be a useful and beneficial method to removal of BPA.

The cyanobiont in an Azolla fern is neither Anabaena nor Nostoc.

Science.gov (United States)

Baker, Judith A; Entsch, Barrie; McKay, David B

2003-12-05

The cyanobacterial symbionts in the fern Azolla have generally been ascribed to either the Anabaena or Nostoc genera. By using comparisons of the sequences of the phycocyanin intergenic spacer and a fragment of the 16S rRNA, we found that the cyanobiont from an Azolla belongs to neither of these genera.

Die beiden Azolla-arten des Niederländischen Pleistozäns

NARCIS (Netherlands)

Florschütz, F.

1938-01-01

Die erste Mitteilung über die Möglichkeit des Vorkommens fossiler Azolla im niederländischen Boden rührt von J. LORIé her, der im Jahre 1905 bei der Beschreibung von Bohrproben die Entdeckung von Makrosporangien von Azolla filiculoides Lam. in einer dünnen Torfschicht unter Vogelenzang erwähnte

The potential of the aquatic water fern Azolla within a biobased economy

Science.gov (United States)

Nierop, Klaas G. J.; Jongerius, Anna L.; Bijl, Peter K.; Bruijnincx, Pieter C. A.; Klein Gebbink, Robertus J. M.; Reichart, Gert-Jan

2014-05-01

Azolla is a free-floating freshwater fern capable of fixing atmospheric carbon dioxide and nitrogen, the latter of which through its symbiosis with the cyanobacteria Anabaena azollae. It is currently ranked among the fastest growing plants on Earth and occurs in both tropical and temperate freshwater ecosystems. Therefore, it is non-directly competitive with food crops. In addition, Azolla does not require inorganic fertilizers, which makes it a potential and unique source of biomass for the sustainable production of fuels and chemicals that are currently derived from fossil (fuel) sources. The biochemical composition of Azolla allows the production of biofuel or biobased chemicals that are of interest to the chemical industry. Of Azolla, two extractable groups of compounds are of particular interest, i.e. the polyphenols (condensed tannins and ester-bound caffeic acid) and the lipids. The antioxidant property of polyphenols and their application to the treatment of cancer, diabetes and cardiovascular diseases has further contributed to the growth of the polyphenol market. In addition, they can be chemically transformed into aromatic platform and specialty chemicals. The composition of the lipid fraction of Azolla is characterized by highly specific compounds consisting of C26-C36 carbon chains all bearing a ω20-hydroxy group. Such compounds produce an oil fraction upon hydrous pyrolysis, or, alternatively, are well suited to be converted to e.g. various specialty chemicals that are hardly available from both natural sources. Indeed, upon chemical conversion these lipids may yield components for fuels, plastics, cosmetics, and lubricants. Another group of interesting compounds within the lipid group are the polyunsaturated fatty acids (PUFAs). The demand for PUFAs has witnessed a significant increase over the last three years, particularly due to their benefits as cholesterol lowering agents. Here we will present some of the thermal and chemical conversions of the

Use of multivitamin, acidifier and Azolla in the diet of broiler chickens.

Science.gov (United States)

Islam, M A; Nishibori, M

2017-05-01

The experiments were carried out to measure the effect of multivitamin, acidifier and Azolla on growth performance, profitability and lipid profiles of blood of broiler chickens to produce safe and cost effective broilers. In experiment 1, 240 day-old Cobb-500 broiler chicks were fed diets; D 1 (control), D 2 (D 1 with 1 mL multivitamin/liter water), D 3 (D 1 with 1 mL acidifier/liter water), D 4 (D 1 with 1 mL multivitamin and 2 mL acidifier/liter water) having 3 replications in each, and 20 chicks/replication. In experiment 2, 150 day-old Cobb-500 broiler chicks were fed diets; T 1 (control), T 2 (5% Azolla in the diet), T 3 (7% Azolla in the diet) and T 4 (T 1 with 1 mL multivitamin and 1 mL acidifier/liter water) having 3 replications in each, and 20 chicks/replication in control, and 10 chicks/replication in the remaining dietary treatment groups for 35 days. In experiment 1, the highest live weight was observed in D 4 (p0.05). The lowest feed conversion ratio (FCR) (p0.05). However, evidently but not significantly, the highest net profit was obtained in D 2 followed by D 4 , D 1 , and D 3 , respectively. In experiment 2, the highest live weight (p0.05). In conclusion, Azolla and acidifier reduced lipid profiles of broiler chickens. Considering net profit and lipid profiles, 5% Azolla may be the suitable dietary group for producing safe and profitable broilers. However, more studies are needed to confirm this study prior to suggesting using Azolla in the poultry industry.

The Eocene Arctic Azolla phenomenon: species composition, temporal range and geographic extent.

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Collinson, Margaret; Barke, Judith; van der Burgh, Johan; van Konijnenburg-van Cittert, Johanna; Pearce, Martin; Bujak, Jonathan; Brinkhuis, Henk

2010-05-01

Azolla is a free-floating freshwater fern that is renowned for its rapid vegetative spread and invasive biology, being one of the world's fastest growing aquatic macrophytes. Two species of this plant have been shown to have bloomed and reproduced in enormous numbers in the latest Early to earliest Middle Eocene of the Arctic Ocean and North Sea based on samples from IODP cores from the Lomonosov Ridge (Arctic) and from outcrops in Denmark (Collinson et al 2009 a,b Review of Palaeobotany and Palynology 155,1-14; and doi:10.1016/j.revpalbo.2009.12.001). To determine the geographic and temporal extent of this Azolla phenomenon, and the spatial distribution of the different species, we have examined samples from 15 additional sites using material from ODP cores and commercial exploration wells. The sites range from the Sub-Arctic (Northern Alaska and Canadian Beaufort Mackenzie Basin) to the Nordic Seas (Norwegian-Greenland Sea and North Sea Basin). Our data show that the Azolla phenomenon involved at least three species. These are distinguished by characters of the megaspore apparatus (e.g. megaspore wall, floats, filosum) and the microspore massulae (e.g. glochidia fluke tips). The Lomonosov Ridge (Arctic) and Danish occurrences are monotypic but in other sites more than one species co-existed. The attachment to one another and the co-occurrence of megaspore apparatus and microspore massulae, combined with evidence that these spores were shed at the fully mature stage of their life cycle, shows that the Azolla remains were not transported over long distances, a fact which could not be assumed from isolated massula fragments alone. Our evidence, therefore, shows that Azolla plants grew on the ocean surfaces for approximately 1.2 million years (from 49.3 to 48.1 Ma) and that the Azolla phenomenon covered the area from Denmark northwards across the North Sea Basin and the whole of the Arctic and Nordic seas. Apparently, early Middle Eocene Northern Hemisphere middle

Lipid Yield and Composition of Azolla filiculoides and the Implications for Biodiesel Production

NARCIS (Netherlands)

Brouwer, Paul; Werf, van der Adrie; Schluepmann, Henriette; Reichart, Gert Jan; Nierop, Klaas G.J.

2016-01-01

The aquatic fern Azolla is one of the fastest-growing nitrogen-fixing plants on Earth and therefore considered as a potential source of biomass for bioenergy production. The lipid fraction from Azolla filiculoides was analyzed to investigate whether it suited biodiesel production. Since the

Lipid yield and composition of Azolla filiculoides and the implications for biodiesel production

NARCIS (Netherlands)

Brouwer, Paul; van der Werf, Adrie; Schluepmann, Henriette; Reichart, Gert Jan; Nierop, Klaas G J

The aquatic fern Azolla is one of the fastest-growing nitrogen-fixing plants on Earth and therefore considered as a potential source of biomass for bioenergy production. The lipid fraction from Azolla filiculoides was analyzed to investigate whether it suited biodiesel production. Since the

Use of multivitamin, acidifier and Azolla in the diet of broiler chickens

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M. A. Islam

2017-05-01

Full Text Available Objective The experiments were carried out to measure the effect of multivitamin, acidifier and Azolla on growth performance, profitability and lipid profiles of blood of broiler chickens to produce safe and cost effective broilers. Methods In experiment 1, 240 day-old Cobb-500 broiler chicks were fed diets; D1 (control, D2 (D1 with 1 mL multivitamin/liter water, D3 (D1 with 1 mL acidifier/liter water, D4 (D1 with 1 mL multivitamin and 2 mL acidifier/liter water having 3 replications in each, and 20 chicks/replication. In experiment 2, 150 day-old Cobb-500 broiler chicks were fed diets; T1 (control, T2 (5% Azolla in the diet, T3 (7% Azolla in the diet and T4 (T1 with 1 mL multivitamin and 1 mL acidifier/liter water having 3 replications in each, and 20 chicks/replication in control, and 10 chicks/replication in the remaining dietary treatment groups for 35 days. Results In experiment 1, the highest live weight was observed in D4 (p0.05. The lowest feed conversion ratio (FCR (p0.05. However, evidently but not significantly, the highest net profit was obtained in D2 followed by D4, D1, and D3, respectively. In experiment 2, the highest live weight (p0.05. Conclusion In conclusion, Azolla and acidifier reduced lipid profiles of broiler chickens. Considering net profit and lipid profiles, 5% Azolla may be the suitable dietary group for producing safe and profitable broilers. However, more studies are needed to confirm this study prior to suggesting using Azolla in the poultry industry.

Breakdown of middle lamella pectin by (●) OH during rapid abscission in Azolla.

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Yamada, Yoshiya; Koibuchi, Mizuki; Miyamoto, Kensuke; Ueda, Junichi; Uheda, Eiji

2015-08-01

Azolla, a small water fern, abscises its roots and branches within 30 min upon treatment with various stresses. This study was conducted to test whether, in the rapid abscission that occurs in Azolla, breakdown of wall components of abscission zone cells by (●) OH is involved. Experimentally generated (●) OH caused the rapid separation of abscission zone cells from detached roots and the rapid shedding of roots from whole plants. Electron microscopic observations revealed that (●) OH rapidly and selectively dissolved a well-developed middle lamella between abscission zone cells and resultantly caused rapid cell separation and shedding. Treatment of abscission zones of Impatiens leaf petiole with (●) OH also accelerated the separation of abscission zone cells. However, compared with that of Azolla roots, accelerative effects in Impatiens were weak. A large amount of (●) OH was cytochemically detected in abscission zone cells both of Azolla roots and of Impatiens leaf petioles. These results suggest that (●) OH is involved in the cell separation process not only in the rapid abscission in Azolla but also in the abscission of Impatiens. However, for rapid abscission to occur, a well-developed middle lamella, a unique structure, which is sensitive to the attack of (●) OH, might be needed. © 2015 John Wiley & Sons Ltd.

Application of Azolla for 2, 4, 6-Trichlorophenol (TCP Removal from Aqueous Solutions

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Mohammad Ali Zazouli

2013-11-01

Full Text Available Background & Aims of the Study: The 2, 4, 6-Trichlorophenol (TCP is a phenolic compound which it can produce adverse effects on human and environment. Therefore, the removal of these compounds is necessary. The aim of this study is the investigation of TCP removal by using Azolla filiculoides biomass. Materials & Methods: The Azolla biomass was dried in the sunlight, and then it was crushed and sieved to particle sizes in range of 1-2 mm. Next treated with 0.1M HCl for a period of 5h. The Azolla was washed with distilled water and it was used as adsorbent. The effect of operating parameters such as pH, contact time, TCP concentration and adsorbent dose on the TCP removal efficiency was investigated. The residues concentration of TCP was measured by spectrophotometer in λ max of 296 nm. Results: In optimum condition (pH 3, contact time 120 min , adsorbent dose 10 gr/l and TCP concentration 10 ppm, Azolla was able to remove 95% of TCP from aqueous solutions. The equilibrium data follows the Langmuir isotherm and the proper kinetic model is pseudo-second model. Conclusions: Adsorption process by Azolla filiculoides is an efficient method for removal of 2, 4, 6-Trichlorophenol from aqueous solutions.

Growth and feed utilization by juvenile grass carp (Ctenopharyngodon idella feed with Azolla filiculoides with low lipid diet/ Desempenho e conversão alimentar de juvenis de carpa capim (Ctenopharyngodon idella alimentadas com Azolla filiculoides e ração com baixo teor lipídico

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Karina Dufech Esteves

2008-08-01

Full Text Available The total supply of fish available for human consumption will depend more of the expansion of low trophy level fish farming than of wild-caught fish. Aquatic plants used at treatment of aquaculture wastewater have been showed like an alternative to exclusive diet feed. The aquatic fern, Azolla filiculoides is an example with high level of protein. Consequently, more research on feed requirements of herbivorous fish is required. The aim of this study was to evaluate the growth performance and feed efficiency of juvenile grass carp (Ctenopharyngodon idella fed with three different diets using low lipid feed and water fern (Azolla filiculoides. The experiment was carried out in nine (9 tanks of 300 L capacity with three fish per tank (initial body weight = 55,43g. Feeding rate was 2.5% Fish were fed on two times a day with three treatments (R= Diet/Azolla on dry weight R= 2.5; R = 5 and R= 10. The specific growth rate (SGR = 1.39%, daily growth gain (DGG = 1.06 g / day and were significantly (p A oferta de pescado para o consumo humano dependerá mais da expansão do cultivo de peixes que se alimentam dos primeiros níveis tróficos do que daqueles oriundos da pesca extrativa. Plantas aquáticas usadas em fitotratamento de efluentes de aquacultura vêm sendo referidas como uma alternativa alimentar ao uso exclusivo de rações. A Azolla filiculoides é uma pteridófita que apresenta alto nível protéico. Assim, pesquisas sobre as exigências nutricionais de espécies herbívoras são necessárias. O objetivo principal deste estudo foi avaliar o crescimento e eficiência alimentar de juvenis de carpa capim (Ctenopharyngodon idella alimentadas com três relações (R entre ração com baixo teor lipídico e a planta aquática in natura (Azolla filiculoides. O experimento foi conduzido em nove reservatórios com capacidade de 300L e três indivíduos por unidade (Peso Inicial = 53,43g. A taxa alimentar diária foi de 2,5%, dividida em duas refei

Improving soil fertility through Azolla application in low land rice: A review

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Purushottam Subedi

2015-04-01

Full Text Available The continuous usages of chemical fertilizers have harmful effects on soil organic matter reserves, soil health and environmental safety. The use of Bio-fertilizers like Azolla not only increases the rice productivity but also improves the long term soil fertility. Azolla is a fast growing aquatic pteridophyte which fixes atmospheric Nitrogen by forming a symbiotic association with the Blue-Green Algae, Anabaena azollae. Azolla is an efficient Nitrogen fixer. It is grown in lowland rice fields because flooded habitat is suitable for it. Under favorable field condition, it fixes atmospheric nitrogen at a rate exceeding that of the Legume-Rhizobium symbiotic relationship. It increases the rice yield equivalent to that produced by 30-60 kg N/ha. As green manure in water logged soil, it enhances the rapid mineralization of nitrogen. It reduces the NH3 volatilization losses through its influence on floodwater pH that leads to the conservation of urea-N in the system to improve the efficiency of N fertilizers. It significantly improves the physical and chemical properties of the soil including improvement in soil microbial activities. It helps in addition of Organic Matter and release of cations such as Magnesium, Calcium and Sodium. The total N, available P and exchangeable K in the soil and N-uptake by rice can be improved. Therefore, Azolla application is considered as a good practice for sustaining soil fertility and crop productivity irrespective of some limitations.

Coupling Fe0 nano particles with living and dead Azolla filicoloides to improve removal of methylene blue from aqueous solution

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Rakhshaee, Roohan

2015-11-01

Fe0 nano particles (FNPs) were connected to the cell wall of the dead and living Azolla filicoloides as an aquatic fern, individually. FNPs mean size was decreased due to the stabilization, especially using the living one. It was compared the results of X-ray photoelectron spectroscopy (XPS), saturation magnetization (Ms), zeta potential (ZP) and thermal analysis (DSC and TGA) of the dead and living Azolla connected to FNPs, and also the findings of potentiometric titration (PT) of the cell wall's pectin of the dead and living Azolla. It was confirmed (by XRD and XPS) that Fe0 nano particles when were connected to the living Azolla did not produce Fe3O4 due to oxidation unlike the bare FNPs and the connected form to the dead Azolla, by reason of the more stabilization (more surface protection) of nano iron particles after connecting to the living Azolla. To adsorb methylene blue by these agents at the optimum pre-treatment pH 10 and adsorption pH 8, the parameters of equilibrium sorption, rate constant of second-order sorption and activation energy were obtained as: living Azolla-FNPs > dead Azolla-FNPs > FNPs > dead Azolla, while, their thermodynamic parameters (ΔG°, ΔH° and ΔS°) had the reverse arrangement. It was also studied the various factors rule such as photoperiod and the presence of heavy metals on the living Azolla growth coupled with FNPs and its MB removal ability.

Heavy metal pollutant tolerance of Azolla pinnata

Energy Technology Data Exchange (ETDEWEB)

Sarkar, A.; Jana, S.

1986-01-01

The effects of Hg, As, Pb, Cu, Cd, and Cr (1,2 and 5 mg L/sup -1/ each) on Azolla pinnata R. Br. were analyzed. The treatments (2 and 5 mg L/sup -1/) of the heavy metal pollutants decreased Hill activity, chlorophyll, protein and dry wt, and increased tissue permeability over control values. The effects were most pronounced with the treatment of 5 mg L/sup -1/. The harmful effects of the metals were, in general, found by the treatments in the order: Cd > Hg > Cu > As > Pb > Cr. There was no significant change in these parameters at 1 mg L/sup -1/ of the metals over control. Thus Azolla pinnata shows tolerance to the heavy metals tested up to 1 mg L/sup -1/ each.

Aquatic Fern (Azolla Sp.) Assisted Synthesis of Gold Nanoparticles

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Jha, Anal K.; Prasad, K.

2016-02-01

Aquatic pteridophyte (Azolla sp.) was taken to assess its potential to synthesize the metal (Au) nanoparticles. The synthesized particles were characterized using X-ray, UV-visible, scanning and transmission electron microscopy analyses. Nanoparticles almost spherical in shape having the sizes of 5-17nm are found. UV-visible study revealed the surface plasmon resonance at 538nm. Responsible phytochemicals for the transformation were principally phenolics, tannins, anthraquinone glycosides and sugars present abundantly in the plant thereby bestowing it adaptive prodigality. Also, the use of Azolla sp. for the synthesis of gold nanoparticles offers the benefit of eco-friendliness.

Metabolic Adaptation, a Specialized Leaf Organ Structure and Vascular Responses to Diurnal N2 Fixation by Nostoc azollae Sustain the Astonishing Productivity of Azolla Ferns without Nitrogen Fertilizer.

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Brouwer, Paul; Bräutigam, Andrea; Buijs, Valerie A; Tazelaar, Anne O E; van der Werf, Adrie; Schlüter, Urte; Reichart, Gert-Jan; Bolger, Anthony; Usadel, Björn; Weber, Andreas P M; Schluepmann, Henriette

2017-01-01

Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N 2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf pockets and belong to the fastest growing plants. Experimental production reported here demonstrated N-fertilizer independent production of nitrogen-rich biomass with an annual yield potential per ha of 1200 kg -1 N fixed and 35 t dry biomass. 15 N 2 fixation peaked at noon, reaching 0.4 mg N g -1 dry weight h -1 . Azolla ferns therefore merit consideration as protein crops in spite of the fact that little is known about the fern's physiology to enable domestication. To gain an understanding of their nitrogen physiology, analyses of fern diel transcript profiles under differing nitrogen fertilizer regimes were combined with microscopic observations. Results established that the ferns adapted to the phototrophic N 2 -fixing symbionts N. azollae by (1) adjusting metabolically to nightly absence of N supply using responses ancestral to ferns and seed plants; (2) developing a specialized xylem-rich vasculature surrounding the leaf-pocket organ; (3) responding to N-supply by controlling transcripts of genes mediating nutrient transport, allocation and vasculature development. Unlike other non-seed plants, the Azolla fern clock is shown to contain both the morning and evening loops; the evening loop is known to control rhythmic gene expression in the vasculature of seed plants and therefore may have evolved along with the vasculature in the ancestor of ferns and seed plants.

Dry weight and N-uptake by rice plants fertilized with azolla and N-15 enriched urea

International Nuclear Information System (INIS)

Abdel-Monem, M.; Gadalla, A.M.; Abbady, Kh.

1994-01-01

Integrated soil fertility management is essential if soil productivity is to be sustained or improved. In view the recently high cost of N-fertilizers, interest was generated in using Azolla in rice fields. A greenhouse experiment was conducted to study the fate of N-15 labelled urea to rice with or without Azolla application, also to examine the effect of the soil moisture regime at the time of urea application on nitrogen recovery. The results indicated that addition of urea to dry soil gave more than 20% of the rice dry matter as compared to the urea application to wet soil which was also reflected on the N-uptake by the rice. Also N-15 recovery by plant was increased from 22% to 41% when urea was applied to wet and dry soil respectively. At the same time N-losses dropped from 62% to 29%. Addition of Azolla to rice provided rice with 63% of the nitrogen provided by urea, this may be attributed not only to N-fixation by Azolla, but also to its role in reducing the N-losses. Application of Azolla reduced the losses of applied nitrogen from 45.5% to 22.5%. Thus, integration between Azolla and urea is valuable in N-fixation as well as inhibiting nitrogen losses. 2 tabs

TRATAMIENTO DE EFLUENTES PISCÍCOLAS (TILAPIA ROJA EN LAGUNAS CON Azolla pinnata

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GUILLERMO CHAUX F

2013-12-01

Full Text Available Los sistemas con plantas acuáticas flotantes son una alternativa económicamente sostenible para el tratamiento de efluentes piscícolas. Se evaluó a escala piloto el desempeñ,o de un sistema de lagunas con Azolla pinnata en serie para el tratamiento de efluentes de cría de tilapia roja durante el proceso de levante y engorde. El sistema construido en la piscícola La Yunga (Popayán, Colombia consistió en dos líneas de cinco lagunas en serie; la primera con A. pinnata y la segunda sin la planta acuática; cada laguna se operó con un tiempo de detención de un día. La evaluación se realizó en época seca. La producción de Azolla fresca osciló entre 42 y 87 g/m2.d y el contenido de proteína entre 18,5% y 20,4%. Las eficiencias de remoción obtenidas en las líneas (con Azolla, sin Azolla fueron respectivamente: 56% y 46% DBO5; 49% y 26% DQO; 56% y 33% SST; 28% y 36% N-NTK; -108% y 23% N-NH4+; 64% y 34% fósforo total, mostrando superioridad del sistema con Azolla. Con solo tres lagunas en serie plantadas con A. pinnata se alcanzan las eficiencias máximas obtenidas en la remoción de DBO5, DQO, SST y fósforo total.

Lipid production in aquatic plant Azolla at vegetative and reproductive stages and in response to abiotic stress.

Science.gov (United States)

Miranda, Ana F; Liu, Zhiqian; Rochfort, Simone; Mouradov, Aidyn

2018-03-01

The aquatic plant Azolla became increasingly popular as bioenergy feedstock because of its high growth rate, production of biomass with high levels of biofuel-producing molecules and ability to grow on marginal lands. In this study, we analysed the contribution of all organs of Azolla to the total yield of lipids at vegetative and reproductive stages and in response to stress. Triacylglycerol-containing lipid droplets were detected in all (vegetative and reproductive) organs with the highest level in the male microsporocarps and microspores. As a result, significantly higher total yields of lipids were detected in Azolla filiculoides and Azolla pinnata at the reproductive stage. Starving changed the yield and composition of the fatty acid as a result of re-direction of carbon flow from fatty acid to anthocyanin pathways. The composition of lipids, in regard the length and degree of unsaturation of fatty acids, in Azolla meets most of the important requirements for biodiesel standards. The ability of Azolla to grow on wastewaters, along with their high productivity rate, makes it an attractive feedstock for the production of biofuels. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

N-Urea Efficiency In Lowland Rice Applied With Azolla

International Nuclear Information System (INIS)

Rasjid, Havid; Sisworo, E.L.; Wemay, Y.; Sisworo, W.H.

2000-01-01

Two N-fertilizer experiments have been conducted using urea tablet and prill urea combined with Azolla application. Twelve treatments have been tested using 2 rice varieties namely Atomita-4 and IR-64. To enable the determination of N-urea efficiency 15 N labelled urea was used. The experiments were conducted in the dry and wet season (DS and WS) 1994/1995 at the experimental station, pusaka negara, Subang West Java. Data obtained from the two experiments showed that the highest N-urea efficiency was found in Atomita-4 applied with urea-tablet (DS=46,1%, WS= 35,8%). Letting the Azolla grow during one lowland rice growth period could increase the N-urea prill efficiency (±5%) compared when no azolla was applied. Apparently Atomita-4 could use N-urea more efficiently compared to IR-64, showing higher grain yield (atomita-4 DS=6.2 ton ha -1 WS=5.9 ton ha -1 ) vs IR-64 (DS=5.8 ton ha -1 , WS=5.3 ton ha -1 ). Decreasing the levels of TSP not influence to the urea efficiency at the DS and WS

Combined use of Azolla and loach suppressed paddy weeds and increased organic rice yield: second season results

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Weiguo Cheng

2015-01-01

Full Text Available Organic farming uses alternatives to agricultural chemicals such as synthetic fertilizers and pesticides. The primary challenge in organic rice farming is controlling weeds without using herbicides and improving rice yield without chemical fertilizers. In our previous paper entitled as combined use of Azolla and loach suppressed weed Monochoria vaginalis and increased rice yield without agrochemicals, we reported the first year rice growth season results from an in situ container experiment. The experiment was designed with 4 treatments—control (with neither Azolla nor loach, Azolla (Azolla alone, loach (loach alone, and Az+Lo (combined Azolla and loach—with 3 replications each. The first year results showed that combined use of Azolla and loach was successful in weed suppression and increase in rice yield in 2012. In this paper, we report the second year results from the continuous container experiment in 2013. M.vaginalis emergences were very low in second year rice growth season on all treatments. Compared first year, the rice yields decreased in second year on all treatments due to different weather condition and with or without organic soybean oil cake application between two rice growth seasons. The second year results also showed the raising loach had a stronger effect to increase tiller and panicle numbers, and spikelet number per panicle, then improve rice yields to 2.3 times than control. The Azolla residues left from first year have weaker effect on rice growth and yield, but increase soil organic matter accumulation at second year. The two years study indicated that combined use of Azolla and loach can meet two of the greatest challenges in organic rice production: providing effective weed control and improving rice nutrition without agrochemicals.

Biotechnological potential of Azolla filiculoides for biosorption of Cs and Sr: Application of micro-PIXE for measurement of biosorption.

Science.gov (United States)

Ghorbanzadeh Mashkani, Saeid; Tajer Mohammad Ghazvini, Parisa

2009-03-01

The presence of Cs and Sr in culture medium of Azolla filiculoides caused about 27.4% and 46.3% inhibition of biomass growth, respectively, in comparison to A. filiculoides control weight which had not metals. Biosorption batch experiments were conducted to determine the Cs and Sr binding ability of native biomass and chemically modified biosorbents derived from Azolla namely ferrocyanide Azolla sorbents type 1 and type 2 (FAS1 and FAS2) and hydrogen peroxide Azolla sorbent (HAS). The best Cs and Sr removal results were obtained when A. filiculoides was treated by 2M MgCl(2) and 30ml H(2)O(2) 8mM at pH 7 for 12h and it was then washed by NaOH solution at pH 10.5 for 6h. Pretreatment of Azolla have been suggested to modify the surface characteristics which could improve biosorption process. The binding of Cs and Sr on the cell wall of Azolla was studied with micro-PIXE and FT-IR.

Separation of abscission zone cells in detached Azolla roots depends on apoplastic pH.

Science.gov (United States)

Fukuda, Kazuma; Yamada, Yoshiya; Miyamoto, Kensuke; Ueda, Junichi; Uheda, Eiji

2013-01-01

In studies on the mechanism of cell separation during abscission, little attention has been paid to the apoplastic environment. We found that the apoplastic pH surrounding abscission zone cells in detached roots of the water fern Azolla plays a major role in cell separation. Abscission zone cells of detached Azolla roots were separated rapidly in a buffer at neutral pH and slowly in a buffer at pH below 4.0. However, cell separation rarely occurred at pH 5.0-5.5. Light and electron microscopy revealed that cell separation was caused by a degradation of the middle lamella between abscission zone cells at both pH values, neutral and below 4.0. Low temperature and papain treatment inhibited cell separation. Enzyme(s) in the cell wall of the abscission zone cells might be involved in the degradation of the pectin of the middle lamella and the resultant, pH-dependent cell separation. By contrast, in Phaseolus leaf petioles, unlike Azolla roots, cell separation was slow and increased only at acidic pH. The rapid cell separation, as observed in Azolla roots at neutral pH, did not occur. Indirect immunofluorescence microscopy, using anti-pectin monoclonal antibodies, revealed that the cell wall pectins of the abscission zone cells of Azolla roots and Phaseolus leaf petioles looked similar and changed similarly during cell separation. Thus, the pH-related differences in cell separation mechanisms of Azolla and Phaseolus might not be due to differences in cell wall pectin, but to differences in cell wall-located enzymatic activities responsible for the degradation of pectic substances. A possible enzyme system is discussed. Copyright © 2012 Elsevier GmbH. All rights reserved.

Determination of thermal stability of specific biomarker lipids of the freshwater fern Azolla through hydrous pyrolysis

Science.gov (United States)

Sap, Merel; Speelman, Eveline N.; Lewan, Michael D.; Sinninghe Damsté, Jaap S.; Reichart, Gert-Jan

2010-05-01

Enormous blooms of the free-floating freshwater fern Azolla occurred within the Arctic Basin during an extended period of ~1.2 Ma during the middle Eocene (Brinkhuis et al. 2006; Speelman et al., GB, 2009). The sustained growth of Azolla, currently ranking among the fastest growing plants on Earth, in a major anoxic basin may have substantially contributed to decreasing atmospheric CO2 levels by burial of Azolla-derived organic matter. Speelman et al. (OG, 2009) reported biomarkers for Azolla (1,w20 C32 - C36 diols, structurally related C29 ω20,ω21 diols, C29 1,20,21 triols, C29 dihydroxy fatty acids as well as a series of wax esters containing these mono- and dihydroxy lipids), which can be used to reconstruct palaeo-environmental conditions. Here we assess the thermal stability of these compounds, to extend their biomarker potential. We specifically focused on the thermal stability of the Azolla biomarkers using hydrous pyrolysis in order to determine which burial conditions allow reconstruction of past occurrences of Azolla. In addition, hydrous pyrolysis was also performed on samples from the Eocene Arctic Ocean (ACEX core), to test if and how the biomarkers change under higher temperatures and pressures in situ. During hydrous pyrolysis, the biomass was heated under high pressure at temperatures ranging between 220 and 365°C for 72 hours. Four experiments were also run using different durations to explore the kinetics of biomarker degradation at specific temperatures. First results indicate that the Azolla specific diols are still present at 220°C, while the corresponding wax esters are already absent. At 300°C all Azolla specific biomarkers are destroyed. More specific determination of the different biomarkers' stability and kinetics would potentially allow the reconstruction of the temperature and pressure history of Azolla deposits. Literature: • Brinkhuis, H., Schouten, S., Collinson, M. E., Sluijs, A., Sinninghe Damste, J. S., Dickens, G. R., Huber

Evaluation of isotopic dilution method for measuring N2 fixation in azolla: comparison with other methods

International Nuclear Information System (INIS)

Sah, R.N.; Goyal, S.S.; Rains, D.W.; Paige, D.F.

1989-01-01

An isotopic dilution method that overcomes the drawbacks of commonly used methods for measuring N 2 fixation by aquatic N‐fixers such as Azolla pinnata‐Anabaena azollae association (Azolla) is presented. The method was compared with 15 N2 gas (while maintaining CO 2 ) and the difference methods of measuring N 2 fixation. The isotopic dilution method was used for two conditions: a. For 15 N‐free growth medium, Azolla was pre‐enriched with 15 N, and N 2 fixation was determined by measuring the dilution of 15 N in the tissue. b. For the growth medium containing N, N2 fixation was determined by providing 15 N enriched ammonium sulfate in the growth medium and measuring 15 N to 14 N ratio in the tissue. An airtight chamber, necessary for 15 N 2 gas and acetylene reduction methods, was not representative of the growing environment of Azolla. Temperature in the airtight chamber was far from uniform and CO 2 was rapidly depleted. The isotopic dilution method is simpler, relatively inexpensive, subject to fewer errors and applicable to more diverse conditions, and yet was as accurate as 15 N2‐gas method. (author)

Coeval Eocene blooms of the freshwater fern Azolla in and around Arctic and Nordic seas

NARCIS (Netherlands)

Barke, J.; Burgh, A.H.P. van der; Konijnenburg-van Cittert, J.H.A. van; Collinson, M.E.; Pearce, M.A.; Bujak, J.; Heilman-Clausen, C.; Lotter, A.F.; Speelman, E.N.; Kempen, M.M.L. van; Reichart, G.-J.; Brinkhuis, H.

2012-01-01

For a short time interval (c. 1.2 Myr) during the early middle Eocene (~ 49 Myr), the central Arctic Ocean was episodically densely covered by the freshwater fern Azolla, implying sustained freshening of surface waters. Coeval Azolla fossils in neighboring Nordic seas were thought to have been

The aquatic fern Azolla as a natural plant-factory for ammonia removal from fish-breeding fresh wastewater.

Science.gov (United States)

Carlozzi, Pietro; Padovani, Giulia

2016-05-01

This study has investigated the potential of an Azolla-Anabaena symbiosis, a marriage between the cyanobacterium Anabaena azollae and the aquatic fern (Azolla), to remove ammonia from freshwater fish breeding areas. Experiments were carried out under artificial light of 20, 70, and 140 μmol m(-2) s(-1). We investigated three different water temperatures for the growing Azolla, ranging from sub-optimal to optimal temperatures (15, 22, and 28 °C). The capability of Azolla to remove ammonia from wastewater was demonstrated, and the highest ammonia concentration tolerated by the symbiosis between Azolla-anabaena without any toxic effect on the aquatic ferns was ascertained. The shortest time taken to remove ammonia from wastes, 2.5 cm deep and at 28 °C, was 40 min. The ammonia removal rate (A RR) was both light and temperature dependent and the highest rate (6.394 h(-1)) was attained at light intensity of 140 μmol m(-2) s(-1) and at a temperature of 28 °C; the lowest (0.947 h(-1)) was achieved at 20 μmol m(-2) s(-1) and 15 °C. The depth of the fish-wastewater pool also affected the A RR with the relation between A RR and the depth being a hyperbolic function.

Coupling Fe{sup 0} nano particles with living and dead Azolla filicoloides to improve removal of methylene blue from aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Rakhshaee, Roohan, E-mail: roohan_rakhshaee@guilan.ac.ir

2015-11-30

Highlights: • The novel living and dead bio–nano couples were prepared. • Living Azolla was more effective stabilizer for nano particles. • Increasing stabilization increased methylene blue (MB) adsorption. • The portion of Fe{sup 0} NPs had the main rule to determine kinetic model to adsorb MB. • It was studied the various factors rule on the living Azolla growth and MB removal. - Abstract: Fe{sup 0} nano particles (FNPs) were connected to the cell wall of the dead and living Azolla filicoloides as an aquatic fern, individually. FNPs mean size was decreased due to the stabilization, especially using the living one. It was compared the results of X-ray photoelectron spectroscopy (XPS), saturation magnetization (Ms), zeta potential (ZP) and thermal analysis (DSC and TGA) of the dead and living Azolla connected to FNPs, and also the findings of potentiometric titration (PT) of the cell wall's pectin of the dead and living Azolla. It was confirmed (by XRD and XPS) that Fe{sup 0} nano particles when were connected to the living Azolla did not produce Fe{sub 3}O{sub 4} due to oxidation unlike the bare FNPs and the connected form to the dead Azolla, by reason of the more stabilization (more surface protection) of nano iron particles after connecting to the living Azolla. To adsorb methylene blue by these agents at the optimum pre-treatment pH 10 and adsorption pH 8, the parameters of equilibrium sorption, rate constant of second-order sorption and activation energy were obtained as: living Azolla–FNPs > dead Azolla–FNPs > FNPs > dead Azolla, while, their thermodynamic parameters (ΔG°, ΔH° and ΔS°) had the reverse arrangement. It was also studied the various factors rule such as photoperiod and the presence of heavy metals on the living Azolla growth coupled with FNPs and its MB removal ability.

Effects of different combinations of Hoagland's solution and Azolla ...

African Journals Online (AJOL)

ALAN

2013-04-17

Apr 17, 2013 ... hydroponic cultures containing different compositions of hydroponic solutions were evaluated in ... (Hoagland's solution minus N solution excluding Azolla; ..... nutrient deficiencies on photosynthesis and respiration in spinach.

Effect of Azolla feeding on the growth, feed conversion ratio, blood biochemical attributes and immune competence traits of growing turkeys.

Science.gov (United States)

Shukla, Mayank; Bhattacharyya, Amitav; Shukla, Pankaj Kumar; Roy, Debashis; Yadav, Brijesh; Sirohi, Rajneesh

2018-04-01

In the recent past,few studies have been carried out in chicken to assess the effect of Azolla meal and raw Azolla feeding on the performance of chicken. If turkeys effectively use unconventional feedstuffs like Azolla without reducing the performance, it will increase the profitability of turkey business. Hence, a study was carried out to evaluate the effect of dried Azolla pinnata vis-a-vis raw Azolla as choice feeding on the growth, feed conversion ratio (FCR), blood biochemical attributes, and immune competence traits of growing turkeys under intensive system. A total of 72, 8-week-old grower turkey poults of black variety were randomly distributed into three dietary treatments having three replicates each with eight birds. The birds of the control group (T1) were fed a basal diet (CP - 19.71% and ME - 2789.79 Kcal/kg), while the other group (T2) and choice-feeding group (T3) were fed 5% of basal diet replaced by dry Azolla powder on DM basis and ad libitumAzolla along with basal diet, respectively. There was no significant difference among the different groups in the average weekly weight gain during the entire experiment. FCR was significantly better (pdiet may improve FCR without any adverse effect on blood biochemical attributes and immune competence traits.

Population isolation results in low genetic variation and high differentiation in Carolina hemlock (tsuga caroliniana), an imperiled southern Appalachian conifer

Science.gov (United States)

Kevin M. Potter; Lia Campbell; Sedley A. Josserand; C. Dana Nelson; Robert M. Jetton

2017-01-01

Carolina hemlock (Tsuga caroliniana) is a rare conifer species that grows in small, isolated populations in the southern Appalachian Mountains of Virginia, North Carolina, South Carolina, Tennessee, and Georgia. The species is additionally imperiled by the hemlock woolly adelgid (Adelges tsugae), an invasive insect that can...

Exploring the effects of inclusion of dietary fresh Azolla on the performance of White Pekin broiler ducks.

Science.gov (United States)

Acharya, Parag; Mohanty, G P; Pradhan, C R; Mishra, S K; Beura, N C; Moharana, B

2015-11-01

The objective of this study was to investigate the dietary advantages of inclusion of unconventional nutrient source, i.e., Azolla in the basal diet of White Pekin broilers. All ducklings were randomly distributed into three treatment groups with three replicates each and each replicate having 12 ducklings and were reared in deep litter system. Groups were subjected to three dietary treatments such as G1: Basal diet, G2: Basal diet + 5% fresh Azolla of basal diet, G3: Basal diet + 10% fresh Azolla of basal diet. During experimental period, parameters, such as bodyweight, bodyweight gain, feed consumption,feed conversion ratio(FCR), and economic of production,wererecorded. The result showed that body weights in every week, except the 5(th) week, did not differ significantly between groups. However, no significant difference was observed between the groups in any week in terms of absolute body weight gain and feed consumption. As regard to FCR, the 10% Azolla group (G3) showed the best feed efficiency followed by the 5% Azolla group (G2) and the control group (G1). On the basis of profit/bird or profit/kg live weight, each of the Azolla-fed group showed a higher economic efficiency than the control. From the experiment, it was concluded that Azollaat 5 or 10% level can be included in the diet to economize the White Pekin broiler farming, and it can be great impetus to poultry farming to include unconventional nutrient source as a dietary supplement.

Potential of macrophyte for removing arsenic from aqueous solution Potencial de remoção de arsênio de solução aquosa por macrofita

Directory of Open Access Journals (Sweden)

F.P. Guimaraes

2012-12-01

Full Text Available The potential of three aquatic macrophytes, Azoll caroliniana, Salvinia minima and Lemna gibba, was evaluated in this work aimed at selection of plants to be used in remediation of environments contaminated by arsenic (As. The experiments were carried out in a greenhouse during six days in pots containing Hoagland solution (¼ ionic strength at As concentrations of 0.5; 2.5 and 5.0 mg L-1. The three species showed greater As accumulation as the concentration of the metalloid in solution increased. However, a reduction was detected in fresh and dry mass gain when the plants were exposed to high As concentrations. The macrophytes showed differences in efficiency of removal of As in solution. A. caroliniana, S. minima and L. gibba accumulated, on average, 0.130; 0.200; and 1.397 mg mDM-1, respectively, when exposed to 5.0 mg L-1 of As. The macrophytes absorbed a greater quantity of As in solution with low phosphate content. The greater As concentration in L. gibba tissues lowered the chlorophyll and carotenoid contents as shown by the high chlorosis incidence. Lemna gibba also exhibited a decrease in leaf size, with the total chlorophyll and carotenoid synthesis not being affected by As in A. caroliniana. This species exhibited purplish leaves with high concentration of anthocyanin, whose presence suggested association to phosphate deficiency. Marginal necrosis occurred on S. minima floating leaves, with the released daughter-plants not showing any visual symptoms during the treatment. The percentage of As removed from the solution decreased when the plants were exposed to high concentrations of the pollutant. Among the three species studied, only L. gibba could be considered an As hyper-accumulator. The use of this plant species for remediation of aquatic environments was shown to be limited and requires further investigation.O potencial de três macrófitas aquáticas - Azolla caroliniana, Salvinia mínima e Lemna gibba - foi avaliado neste

Endosulfan induced changes in growth rate, pigment composition and photosynthetic activity of mosquito fern Azolla microphylla

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Raja W.

2012-11-01

Full Text Available This paper is the first in a series reporting a study on the effects of different concentrations of insecticide, Endosulfan (0-600ppm was premeditated on 5th day after insecticide exposure with respect to growth rate, pigment composition and photosynthetic activity of Azolla microphylla under laboratory conditions which become non-target organism in the rice fields. Endosulfan inhibited the relative growth rate, pigment content and photosynthetic O2 evolution. Phycocyanin was main target followed by carotenoid and total chlorophyll. Significant increase in pigment, flavonoid and Anthocyanin was noticed after six days of treatment. In contrast to the photosynthetic activity, the rate of respiration in Azolla microphylla was increased significantly. Our results show that Endosulfan at normally recommended field rates and intervals are seldom deleterious to the beneficial and Eco friendly Azolla microphylla and their activities and thus in turn suppress plant growth and development. Phytotoxity of Azolla microphylla can be minimized by restrictions on application, timing, method and rate of application.

Effect of azolla-incorporated diets on the growth and survival of Labeo fimbriatus during fry-to-fingerling rearing

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B. Gangadhar

2015-12-01

Full Text Available An experiment of 75 days duration was conducted in fertilized outdoor circular cement tanks (1,000 L with soil base for evaluating the growth and survival of Labeo fimbriatus fry fed with pelleted feed containing varied levels of dried azolla (Azolla pinnata. The Control feed contained 45% groundnut oilcake plus 45% rice bran and 10% finger millet flour added as binder for pelleting. Dried azolla powder was incorporated into the feed at 10, 20, 30 and 40% levels, replacing the groundnut cake and rice bran proportionately. L. fimbriatus (mean length 2.42 cm fry were stocked in all the tanks at 30 m−3. The fish were fed 10% of body weight during the first month, followed by 7% during the second month and 5% during the last 15 days. Incorporation of azolla did not affect (p > 0.05 the water quality, growth and survival of fingerlings at harvest. Incorporation of azolla in the diet reduced the cost of feed (Rs. per 100 g biomass; Rs: Indian rupee, INR; 1 INR ≈ 0.015 EUR from 3.35 to 2.53, with a cost saving of 24.48%. The study indicated the possibility of incorporating azolla in diets of L. fimbriatus up to 40% during fry-to-fingerling rearing, resulting in savings on feed cost.

Growth performance and phytoremediation ability of Azolla pinnata ...

African Journals Online (AJOL)

ADOWIE PERE

Growth performance and phytoremediation ability of Azolla pinnata in produced water ... Toxicity symptoms of produced water on the plant include chlorosis, frond ... easily to various conditions and can tolerate a wide ... The aquatic macrophyte used for this experiment was .... the Kathloni oilfield in northeast India.

Application of Azolla and intermittent irrigation to improve the productivity and nutrient contents of local black rice variety

Science.gov (United States)

Sulandjari; Yunindanova, M. B.

2018-03-01

Black rice is a local rice variety that contains a high level of anthocyanin pigment. Anthocyanin has been reported to be very effective in reducing cholesterol levels as well as cancer cell invasion. One of the main problems in rice cultivation is lack of water. System of Rice Intensification (SRI) has shown to be able to increase rice productivity by increasing the number of tillers. This system is known as a water-efficient cultivation. Other rice cultivation barrier is related to the use of nitrogen fertilizer. One of replacement of nitrogen fertilizer is by adding azolla. The objective of this research was identifying growth and yield of organic black rice with intermittent irrigation and application of azolla. The plant material used was black rice Cempo variety from Sleman, Yogyakarta. This experiment utilized 4 dosages of azolla as the first treatment: 100 gm-2, 200 gm-2 and 400 gm-2. The second treatment was water supply consisted of continuous flooded 2 cm; flooded 2 cm every 3 days; flooded 2 cm every 6 days. The results depicted that the application of azolla was able to increase the growth of black rice. Azolla of 200 gm-2 and 400 gm-2 and intermittent 3 days to 6 days generated higher dry grain, anthocyanin and antioxidant. Azolla 200 gm-2 with intermittent irrigation 3 days could be a good combination to improve plant growth, yield and properties of local black rice.

Polyamine-Induced Rapid Root Abscission in Azolla pinnata.

Science.gov (United States)

Gurung, Sushma; Cohen, Michael F; Fukuto, Jon; Yamasaki, Hideo

2012-01-01

Floating ferns of the genus Azolla detach their roots under stress conditions, a unique adaptive response termed rapid root abscission. We found that Azolla pinnata plants exhibited dose-dependent rapid root abscission in response to the polyamines spermidine and spermine after a substantial time lag (>20 min). The duration of the time lag decreased in response to high pH and high temperature whereas high light intensity increased the time lag and markedly lowered the rate of abscission. The oxidation products of polyamines, 1,3-diaminopropane, β-alanine and hydrogen peroxide all failed to initiate root abscission, and hydroxyethyl hydrazine, an inhibitor of polyamine oxidase, did not inhibit spermine-induced root abscission. Exposure of A. pinnata to the polyamines did not result in detectable release of NO and did not affect nitrite-dependent NO production. The finding of polyamine-induced rapid root abscission provides a facile assay for further study of the mode of action of polyamines in plant stress responses.

Pyrolysis of azolla, sargassum tenerrimum and water hyacinth for production of bio-oil.

Science.gov (United States)

Biswas, Bijoy; Singh, Rawel; Krishna, Bhavya B; Kumar, Jitendra; Bhaskar, Thallada

2017-10-01

Pyrolysis of azolla, sargassum tenerrimum and water hyacinth were carried out in a fixed-bed reactor at different temperatures in the range of 300-450°C in the presence of nitrogen (inert atmosphere). The objective of this study is to understand the effect of compositional changes of various aquatic biomass samples on product distribution and nature of products during slow pyrolysis. The maximum liquid product yield of azolla, sargassum tenerrimum and water hyacinth (38.5, 43.4 and 24.6wt.% respectively) obtained at 400, 450 and 400°C. Detailed analysis of the bio-oil and bio-char was investigated using 1 H NMR, FT-IR, and XRD. The characterization of bio-oil showed a high percentage of aliphatic functional groups and presence of phenolic, ketones and nitrogen-containing group. The characterization results showed that the bio-oil obtained from azolla, sargassum tenerrimum and water hyacinth can be potentially valuable as a fuel and chemicals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nitrogen and azolla response on growth of rice plant of Mitra-I variety with SRI method

International Nuclear Information System (INIS)

Nurmayulis; Putra Utama; Dewi Firnia; Hasnan Yani; Ania Citraresmini

2011-01-01

The research was conducted in Cisadap, Bunter Village, District of Sukadana, Ciamis Regency, West Java Province from January to May 2011. This study was carried out to know the response of growth of rice plant which was fertilized by nitrogen fertilizer and Azolla michrophylla using the system of rice intensification. This research used five dozes of nitrogen fertilizer (0 %, 25 %, 50 %, 75 %, 100 %) from N 92 kg ha -1 as a recommended nitrogen fertilizer (urea 200 kg ha -1 ), and also 1,13 ton ha -1 Azolla michrophylla. The result obtained from this research showed that the application of N fertilizer at 50 % of the recommend dose (100 kg ha -1 ) with adding Azolla at a rate of 1.13 t ha -1 gave good result in the terms of plant height at 2-6 weeks after planting and number of tillers at 2-7 weeks after planting. Interaction of the 50 % N fertilizer from the recommended dose planting 1,13 t ha -1 give the highest dry weight of Azolla of plants at seven weeks after planting. (author)

Fermentation of Azolla sp. leaves and the utilization as a feed ingredient of tilapia Oreochromis sp.

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Nur Bambang Priyo Utomo

2015-03-01

Full Text Available ABSTRACTThe objective of this study was to study the effect of incubation period on the nutritional content of Azolla sp. meal fermented by Trichoderma harzianum, and its optimum supplementation level in the feed of tilapia Oreochromis sp. In incubation period treatments, fermentation of Azolla meal was performed in two, six, eight, and ten days (AF2, AF6, AF8, AF10 using Trichoderma harzianum as the fermentor. The fish used in this study was tilapia Oreochromis sp. with an average weight of 10.59±1.29 g. The design of the feeding treatments was repeletting commercial feed with Azolla leaves by with different supplementation levels, i.e. 0% (A/control, 30% (B, 60% (C, and 90% (D. Faecal collection for digestibility measurement was conducted for 15 days and fish growth rate was observed for 40 days. Azolla meal fermented for two days (AF2 showed the best results among the other treatments with a crude fiber decrease of 37.19% and protein increase of 38.65%. The results of this study indicate that fermentation can increase the nutritional quality of Azolla meal and its most optimal supplementation level in the diet of tilapia is 30%.Keywords: crude fiber, Azolla sp., tilapiaABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh lama waktu fermentasi daun mata lele Azolla sp. menggunakan kapang Trichoderma harzianum serta dosis optimal dalam pakan ikan nila Oreochromis sp. Proses fermentasi tepung daun mata lele dilakukan selama dua, enam, delapan, dan sepuluh hari (AF2, AF6, AF8, AF10. Ikan uji pada penelitian ini menggunakan ikan nila Oreochromis sp. dengan bobot rata-rata 10,59±1,29 g yang ditebar sebanyak 6 ekor/akuarium berukuran 50×45×30 cm3. Sebagai pakan perlakuan yakni repeletting daun mata lele dengan pakan komersil pada tingkat suplementasi 0% (A/kontrol, 30% (B, 60% (C, dan 90% (D. Pemeliharaan ikan uji dan pengumpulan data dilakukan dengan mengumpulkan feses ikan untuk uji ketercernaan selama 15 hari dan mengamati pertumbuhan

Optimation of Nitrogen and Phosphorus in Azolla Growth as Biofertilizer

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Hany Handajani

2013-03-01

Full Text Available Nitrogen is one of the most important minerals for living organisms. Azolla is known as a small water fern which can fix nitrogen through the symbiotic association with the blue green algae Anabaena. Experimental studies were carried out in the glass house, investigating the growth of Azolla using different levels of nitrogen and phosphorus in the media. The experiment used 12 treatments with 3 levels of nitrogen (0, 5, and 10 mg atom/L and 4 levels of phosphorus (0, 10, 20, and 30 mg atom/l in a factorial design with 3 replicates. The results show that the highest biomass for fresh weight (13.28 g, dry weight (1,126 g, and the fastest doubling time (7.71 days were found in combination of 10 mg atom/L N and 30 mg atom/L P. Meanwhile, the highest protein content was found in combination of 5 mg atom/L N and 20 mg atom/L P. After the third day heterocyst cells in Anabaena could only be found in those two combinations, but the highest heterocyst cells was found in the lower N and P combination similar to the highest protein content. Further experiment is suggested to introduce Azolla as bio-fertilizer for acid water system, such as peat land water.

Is there foul play in the leaf pocket? The metagenome of floating fern Azolla reveals endophytes that do not fix N2but may denitrify

NARCIS (Netherlands)

Dijkhuizen, Laura W.; Brouwer, Paul; Bolhuis, Henk; Reichart, Gert Jan; Koppers, Nils; Huettel, Bruno; Bolger, Anthony M.; Li, Fay Wei; Cheng, Shifeng; Liu, Xin; Wong, Gane Ka Shu; Pryer, Kathleen; Weber, Andreas P.M.; Bräutigam, Andrea; Schluepmann, Henriette

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla

APLIKASI KOMBINASI KOMPOS JERAMI, KOMPOS AZOLLA DAN PUPUK HAYATI UNTUK MENINGKATKAN JUMLAH POPULASI BAKTERI PENAMBAT NITROGEN DAN PRODUKTIVITAS TANAMAN PADI BERRBASIS IPAT-BO

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Ferina Rosiana

2013-03-01

Full Text Available Penelitian untuk mengetahui efek pemberian kombinasi kompos jerami dengan Azolla dan pupuk hayati majemuk terhadap peningkatan populasi bakteri penambat N dan produktivitas tanaman padi dengan teknologi IPAT-BO dilaksanakan dari bulan April hingga Juli 2012 di kebun percobaan Fakultas Pertanian, Universitas Padjadjaran, Jatinangor, dengan ketinggian + 740 m dpl. Penelitian ini menggunakan rancangan acak kelompok faktor tunggal dengan dua belas perlakuan dan tiga kali ulangan. Perlakuan terdiri dari (A tanpa kompos jerami, (B kompos jerami 2,5 ton ha-1, (C kompos jerami 5 ton ha-1, (D kompos Azolla 0,5 ton ha-1, (E kompos jerami 2,5 ton ha-1 + kompos Azolla 0,5 ton ha-1, (F kompos jerami 5 ton ha-1 + kompos Azolla 0,5 ton ha-1, (G pupuk hayati 400 g ha-1, (H kompos jerami 2,5 ton ha-1 + pupuk hayati 400 g ha-1, (I kompos jerami 5 ton ha-1 + pupuk hayati 400 g ha-1, (J kompos Azolla 0,5 ton ha-1 + pupuk hayati 400 g ha-1, (K kompos jerami 2,5 ton ha-1 + kompos Azolla 0,5 ton ha-1 + pupuk hayati 400 g ha-1, (L kompos jerami 5 ton ha-1 + kompos Azolla 0,5 ton ha-1 + pupuk hayati 400 g ha-1.Aplikasi perlakuan kompos jerami, kompos Azolla dan pupuk hayati majemuk memberikan pengaruh terhadap populasi penambat N (Azotobacter sp. dan Azospirilium sp. dan produktifitas tanaman padi. Aplikasi kompos jerami 2,5 ton ha-1 dengan pupuk hayati 400 g ha-1 memberikan hasil GKP yaitu 64,39 g tanaman-1 (6,13 ton ha-1. Kata kunci: IPAT-BO, kompos Azolla, kompos jerami, pupuk hayati.

Effect of Azolla feeding on the growth, feed conversion ratio, blood biochemical attributes and immune competence traits of growing turkeys

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Mayank Shukla

2018-04-01

Full Text Available Background and Aim: In the recent past, few studies have been carried out in chicken to assess the effect of Azolla meal and raw Azolla feeding on the performance of chicken. If turkeys effectively use unconventional feedstuffs like Azolla without reducing the performance, it will increase the profitability of turkey business. Hence, a study was carried out to evaluate the effect of dried Azolla pinnata vis-a-vis raw Azolla as choice feeding on the growth, feed conversion ratio (FCR, blood biochemical attributes, and immune competence traits of growing turkeys under intensive system. Materials and Methods: A total of 72, 8-week-old grower turkey poults of black variety were randomly distributed into three dietary treatments having three replicates each with eight birds. The birds of the control group (T1 were fed a basal diet (CP - 19.71% and ME - 2789.79 Kcal/kg, while the other group (T2 and choice-feeding group (T3 were fed 5% of basal diet replaced by dry Azolla powder on DM basis and ad libitum Azolla along with basal diet, respectively. Results: There was no significant difference among the different groups in the average weekly weight gain during the entire experiment. FCR was significantly better (p<0.05 in the choice-feeding group compared to the other two experimental groups during 8-16 weeks of age. There was no significant difference among the treatment groups in any of the blood biochemical indices except plasma uric acid, which was significantly decreased (p<0.01 in T2 compared to T1 at 16 weeks of age. HA and IgM response to 1% sheep red blood cells (log2 titer were numerically better in T2 and T3 compared to the T1. Conclusion: Thus, it may be inferred that choice feeding with Azolla, and basal diet may improve FCR without any adverse effect on blood biochemical attributes and immune competence traits.

L-Myo-inositol 1-phosphate synthase in the aquatic fern Azolla filiculoides.

Science.gov (United States)

Benaroya, Rony Oren; Zamski, Eli; Tel-Or, Elisha

2004-02-01

L-Myo-inositol 1-phosphate synthase (INPS EC 5.5.1.4) catalyzes the conversion of D-glucose 6-phosphate to L-myo-inositol 1-phosphate. INPS is a key enzyme involved in the biosynthesis of phytate which is a common form of stored phosphates in higher plants. The present study monitored the increase of INPS expression in Azolla filiculoides resulting from exposure to inorganic phosphates, metals and salt stress. The expression of INPS was significantly higher in Azolla plants that were grown in rich mineral growth medium than those maintained on nutritional growth medium. The expression of INPS protein and corresponding mRNA increased in plants cultured in minimal nutritional growth medium when phosphate or Zn2+, Cd2+ and NaCl were added to the growth medium. When employing rich mineral growth medium, INPS protein content increased with the addition of Zn2+, but decreased in the presence of Cd2+ and NaCl. These results indicated that accumulation of phytate in Azolla is a result of the intensified expression of INPS protein and mRNA, and its regulation may be primarily derived by the uptake of inorganic phosphate, and Zn2+, Cd2+ or NaCl.

Invasion and spreading of Cabomba caroliniana revealed by RAPD markers

Science.gov (United States)

Jin, Xiaofeng; Ding, Bingyang; Gao, Shuqin; Jiang, Weimei

2005-12-01

Applying randomly amplified polymorphic DNA (RAPD), the genetic variation of Cabomba caroliniana Gray (cabomba or fanwort), a new alien plant in China, was analyzed in this paper. Total 143 bands, including 47 polymorphic bands, were amplified from 23 primers in 20 samples. The sampling distance was large, but its genetic diversity was low. The main results were that: (1) Cabomba, which grew and dispersed mainly in fragment, was an abundant and dominant species in freshwater, and its main dispersal mechanism was vegetative reproduction (2) Cabomba was originally introduced into China as an aquarium submerged plant. Somehow, those discarded cabomba became invasive species in the areas of Hangzhou, Shanghai, and Meicheng, and other places. (3) Although the level of genetic diversity in cabomba was low, their rapid dispersion and propagation could seriously harm to local aquatic community. Therefore, specific measure should be used to control cabomba from uncontrolled spreading and damage to local vegetation communities.

Ability of the aquatic fern Azolla to remove chemical oxygen demand and polyphenols from olive mill wastewater

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Sacchi, Angelo

2007-03-01

Full Text Available We investigated the biofiltration ability of the aquatic fern Azolla to remove polyphenols and chemical oxygen demand (COD from olive mill wastewater (OMWw collected from the traditional (TS and continuous (CS extraction systems. Azolla biomass was packed into five sequential Imhoff cones and five sequential columns. In both experiments, the filtrates collected from the 5th biofilter showed a decrease in polyphenol contents: from 7650 mg l–1 to 3610 mg l–1 in TS OMWw and from 3852 mg l–1 to 1351 mg l–1 in CS OMWw. The COD contents decreased from 110200 mg L–1 to 52400 mg L–1 in TS OMWw and from 41600 mg L–1 to 2300 mg L–1 in CS OMWw. A 5:1 OMWw to Azolla-fresh-weight ratio was optimal for both polyphenol and COD removal. The biofiltration ability of alfalfa was compared with that of Azolla, but the treatment with alfalfa did not result in the reduction of COD or polyphenols.La eficacia del helecho de agua azolla para eliminar polifenoles y reducir la demanda química de oxígeno (DQO de los alpechines obtenidos en el proceso de obtención tradicional y continuo del aceite de oliva, fue investigado mediante ensayos de filtración. Cinco conos secuenciales de Imhoff y cinco columnas secuenciales se rellenaron de biomasa de Azolla. En ambos experimentos, el filtrado procedente de la quinta extracción mostró una disminución en el contenido de polifenoles de 7650 mg L–1 a 3610 mg L–1en el alpechín obtenido mediante el sistema tradicional y de 3852 mg L–1 a 1351 mg L–1en el alpechín del sistema continuo. La demanda química de oxígeno del alpechín del sistema tradicional disminuyó de 110200 mg L–1 a 52400 mg L–1 en y de 41600 mg L–1a 2300 mg L–1en el procedente del sistema continuo. Una proporción en peso 5:1 de alpechín: Azolla fue la óptima tanto para la reducción de los polifenoles como para la de la DQO. La eficiencia del tratamiento biológico con alfalfa se comparó con la obtenida con Azolla. Los

Effect of P nature phosphate dosage and embedding time of Azolla mycrophylla Kaulfuss on Yield of Rice (Oryza sativa L.

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Mahmudah Hamawi

2016-12-01

Full Text Available The effort of growing azolla in intercroping rice will be hoped to supply a green manure for rice plants. Additing P of the phosphat rock in the field can be expected to increase the result of rice yield.The research was conducted on December 2, 2006 to April 5, 2007 at Tegalgondo Karangploso of Malang. onsidering those problems, the researcher employs the factorial group randome desigh that compose two factor by controlling as comparison tool (inorganic treatment. The first factor is P in the phosphat rock contained 4 stages. As followed Po (without P, P1 (25 kg P ha-1, P2 (50 kg P ha-1, P3 (25 kg P ha-1. The second factor is time of incorporated Azolla microphylla Kaulfuss (W, which consist 4 stage. As followed W1 (incorporated 1 day before transplanting rice, W2 (50 % the azolla biomass in the field was incorporated during 14, 28, and 42 days after transplanting rice, W3 (50 % the azolla biomass in the field was incorporated during 21, and 49 days after transplanting rice, W4 (50 % the azolla biomass in the field was incorporated during 35 days after transplanting rice. The research was replicated 3 replications. The research finding showed that phosphat rock with 25 kg of P ha-1 doses combinationed with time of incorporating the azolla biomass at 14, 28 and 42 days after transplanting rice, the result of rice would be increasing in 31,4 % and R/C value resulted 1,47. Giving phosphat rock with 25 – 75 kg P ha-1 doses increased the azolla biomass at 146,4 % until 153 % and increased the yield of rice at 21,1% until 43,8 %.

Effect of partial supplementation of sun-dried Azolla as a protein source on the immunity and antioxidant status of commercial broilers.

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Chichilichi, Biswal; Mohanty, G P; Mishra, S K; Pradhan, C R; Behura, N C; Das, A; Behera, K

2015-09-01

The present study was conducted to evaluate the effect of partial supplementation of sun-dried Azolla as a protein source on the immunity of commercial broilers in coastal Odisha. A 180 day-old broiler chicks were distributed in six dietary treatments viz. C1: Basal diet, C2: Basal diet + enzyme, T1: Basal diet +5% protein from Azolla, T2: Basal diet + 5% protein from Azolla + enzyme, T3: Basal diet +10% protein from Azolla, and T4: Basal diet + 10% protein from Azolla + enzyme. Cutaneous basophilc hypersensitivity (CBH) and humoral immunity response were determined at the 38(th) day of age. At 42(nd) day, the weight of lymphoid organs, an antioxidant enzyme, and lipid peroxidation activity were determined. The CBH response did not differ significantly among the treated groups, but the sheep red blood cells response was significantly higher in T4. The weight of lymphoid organs or immune organs of all the treated groups did not differ significantly (p>0.05). The erythrocyte catalase level of T4 group was found to be significantly higher than rest of the treated groups except T3. It may be concluded that supplementation of Azolla at 10% of dietary protein requirement along with enzyme supplementation in an isonitrogenous diet showed a better immune response in broilers.

Effect of partial supplementation of sun-dried Azolla as a protein source on the immunity and antioxidant status of commercial broilers

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Biswal Chichilichi

2015-09-01

Full Text Available Aim: The present study was conducted to evaluate the effect of partial supplementation of sun-dried Azolla as a protein source on the immunity of commercial broilers in coastal Odisha. Materials and Methods: A 180 day-old broiler chicks were distributed in six dietary treatments viz. C1: Basal diet, C2: Basal diet + enzyme, T1: Basal diet +5% protein from Azolla, T2: Basal diet + 5% protein from Azolla + enzyme, T3: Basal diet +10% protein from Azolla, and T4: Basal diet + 10% protein from Azolla + enzyme. Cutaneous basophilc hypersensitivity (CBH and humoral immunity response were determined at the 38th day of age. At 42nd day, the weight of lymphoid organs, an antioxidant enzyme, and lipid peroxidation activity were determined. Results: The CBH response did not differ significantly among the treated groups, but the sheep red blood cells response was significantly higher in T4. The weight of lymphoid organs or immune organs of all the treated groups did not differ significantly (p>0.05. The erythrocyte catalase level of T4 group was found to be significantly higher than rest of the treated groups except T3. Conclusion: It may be concluded that supplementation of Azolla at 10% of dietary protein requirement along with enzyme supplementation in an isonitrogenous diet showed a better immune response in broilers.

Azolla as a component of the space diet during habitation on Mars

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Katayama, Naomi; Yamashita, Masamichi; Kishida, Yoshiro; Liu, Chung-Chu; Watanabe, Iwao; Wada, Hidenori; Space Agriculture Task Force

We evaluate a candidate diet and specify its space agricultural requirements for habitation on Mars. Rice, soybean, sweet potato and a green-yellow vegetable have been selected as the basic vegetarian menu. The addition of silkworm pupa, loach, and Azolla to that basic menu was found to meet human nutritional requirements. Co-culture of rice, Azolla, and loach is proposed for developing bio-regenerative life support capability with high efficiency of the usage of habitation and agriculture area. Agriculture designed under the severe constraints of limited materials resources in space would make a positive contribution toward solving the food shortages and environmental problems facing humans on Earth, and may provide an effective sustainable solution for our civilization.

Phytoremediation of Hg and Cd from industrial effluents using an aquatic free floating macrophyte Azolla pinnata.

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Rai, Prabhat Kumar

2008-01-01

The level of heavy metal pollution in Singrauli, an industrial region in India, was assessed and the phytoremediation capacity of a small water fern, Azolla pinnata R.BR (Azollaceae), was observed to purify waters polluted by two heavy metals, i.e., mercury (Hg) and cadmium (Cd) under a microcosm condition. Azolla pinnata is endemic to India and is an abundant and easy-growing free-floating water fern usually found in the rice fields, polluted ponds, and reservoirs of India. The fern was grown in 24 40-L aquariums containing Hg2+ and Cd2+ ions each in concentrations of 0.5, 1.0, and 3.0 mgL(-1) during the course of this study. The study revealed an inhibition of Azolla pinnata growth by 27.0-33.9% with the highest in the presence of Hg (II) ions at 0.5 mgL(-1) in comparison to the control After 13 days of the experiment, metal contents in the solution were decreased up to 70-94%. In the tissues of Azolla pinnata, the concentration of selected heavy metals during investigation was recorded between 310 and 740 mgKg(-1) dry mass, with the highest levelfoundfor Cd (II) treatment at 3.0 mgL(-1) containing a metal solution.

Ketersediaan Nitrogen Tanah dan Pertumbuhan Tanaman Bayam (Amaranthus tricolor L. yang Diperlakukan dengan Pemberian Pupuk Kompos Azolla

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Lukman Amir

2014-01-01

Full Text Available DOWNLOAD PDFPenelitian  ini  bertujuan  untuk  mengetahui kadar  nitogen  tanah  dan  pertumbuhantanaman bayam yang diberi pupuk kompos Azolla. Penelitian ini menggunakan rancanganacak kelompok (RAK yang terdiri atas 2 kelompok, dimana tiap kelompok terdiri atas 4perlakuan dan  1  kontrol  dengan  3  ulangan.  Parameter  pengamatan adalah  pertumbuhantanaman bayam yang meliputi tinggi tanaman (cm, berat kering tanaman bayam (gram,kadar amonium (NH4+ dan nitrat (NO3- pada tanah serta kadar nitrat (NO3- air lindihan.Hasil  penelitian  menunjukkan  bahwa  pupuk  kompos  Azolla  mulai  berpengaruh  nyataterhadap  tinggi  tanaman  sejak  pengamatan  minggu  ke-tiga  dan  berpengaruh  nyata  pulaterhadap berat kering tanaman bayam. Pemberian pupuk kompos Azolla berpengaruh nyataterhadap kadar amonium dan nitrat tanah masing-masing pada minggu ke dua dan mingguke  dua  dan  ke  empat.  Disamping  itu  pemberian  pupuk  tersebut  juga  berpengaruh  nyataterhadap kadar nitrat pada air lindihan.Kata kunci : Pupuk kompos Azolla, pertumbuhan tanaman bayam, nitrogen tanah

Evaluation of butachlor for control of some submerged macrophytes along with its impact on biotic components of freshwater system

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A. Chattopadhyay, S. Adhikari, S. P. Adhikary, S. Ayyappan

2006-04-01

Full Text Available In this investigation, the efficacy of the herbicide butachlor, (N-butoxymethyl-2 chloro-21, 61 diethyl acetanilide was tested against few common submerged macrophytes namely Hydrilla (Hydrilla verticillata (L. Royale, Najas (Najas minor All., Nechamandra (Nechamandra alternifolia (Roxb. Thwaites and Ottelia (Ottelia alismoides (L. Pers. of freshwater fish ponds. Almost complete decay of Hydrilla, Nechamandra and Ottelia was achieved at 7.5 L of active ingredient/ha/m butachlor within 15 days while the herbicide showed no negative effect on Najas. However at the same concentration of butachlor, total mortality of zooplankton and water fern Azolla (Azolla caroliniana Lamarck occurred within seven days. In case of few freshwater fish species like Rohu (Labeo rohita, Channa (Channa punctatus, Anabas (Anabas testitudineus and Heteropneustes (Heteropneustes fossilis, total mortality occurred upto 90 days after application of the same dose of butachlor but fish survived beyond 120 days of herbicide application indicating degradation of the herbicides.

Kinetic modeling and thermodynamic study to remove Pb(II), Cd(II), Ni(II) and Zn(II) from aqueous solution using dead and living Azolla filiculoides.

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Rakhshaee, Roohan; Khosravi, Morteza; Ganji, Masoud Taghi

2006-06-30

Dead Azolla filiculoides can remove Pb(2+),Cd(2+), Ni(2+) and Zn(2+) corresponding to second-order kinetic model. The maximum adsorption capacity (Q(max)) to remove these metal ions by the alkali and CaCl(2)/MgCl(2)/NaCl (2:1:1, molar ratio) activated Azolla from 283 to 313K was 1.431-1.272, 1.173-0.990, 1.365-1.198 and 1.291-0.981mmol/g dry biomass, respectively. Q(max) to remove these heavy metals by the non-activated Azolla at the mentioned temperature range was obtained 1.131-0.977, 1.092-0.921, 1.212-0.931 and 1.103-0.923mmol/g dry biomass, respectively. In order to remove these metal ions by the activated Azolla, the enthalpy change (DeltaH) was -4.403, -4.495, -4.557 and -4.365kcal/mol and the entropy change (DeltaS) was 2.290, 1.268, 1.745 and 1.006cal/molK, respectively. While, to remove these metal ions by the non-activated Azolla, DeltaH was -3.685, -3.766, -3.967 and -3.731kcal/mol and DeltaS was 2.440, 1.265, 1.036 and 0.933cal/molK, respectively. On the other hand, the living Azolla removed these heavy metals corresponding to first-order kinetic model. It was also shown that pH, temperature and photoperiod were effective both on the rate of Azolla growth and the rate of heavy metals uptake during 10 days. It was appeared the use of Ca(NO(3))(2) increased both Azolla growth rate and the rate of heavy metals uptake while the using KNO(3) although increased Azolla growth rate but decreased the rate of heavy metals uptake.

Kinetic modeling and thermodynamic study to remove Pb(II), Cd(II), Ni(II) and Zn(II) from aqueous solution using dead and living Azolla filiculoides

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Rakhshaee, Roohan [Department of Applied Chemistry, Faculty of Chemistry, Islamic Azad University, Rasht Branch, P.O. Box 41335-3516, Rasht (Iran, Islamic Republic of); Khosravi, Morteza [Department of Applied Chemistry, Faculty of Chemistry, Islamic Azad University, North Tehran Branch, P.O. Box 191367-4711, Tehran 191367-4711 (Iran, Islamic Republic of)]. E-mail: drm_khosravi@yahoo.com; Ganji, Masoud Taghi [Department of Applied Chemistry, Faculty of Chemistry, Islamic Azad University, North Tehran Branch, P.O. Box 191367-4711, Tehran 191367-4711 (Iran, Islamic Republic of)

2006-06-30

Dead Azolla filiculoides can remove Pb{sup 2+},Cd{sup 2+}, Ni{sup 2+} and Zn{sup 2+} corresponding to second-order kinetic model. The maximum adsorption capacity (Q {sub max}) to remove these metal ions by the alkali and CaCl{sub 2}/MgCl{sub 2}/NaCl (2:1:1, molar ratio) activated Azolla from 283 to 313 K was 1.431-1.272, 1.173-0.990, 1.365-1.198 and 1.291-0.981 mmol/g dry biomass, respectively. Q {sub max} to remove these heavy metals by the non-activated Azolla at the mentioned temperature range was obtained 1.131-0.977, 1.092-0.921, 1.212-0.931 and 1.103-0.923 mmol/g dry biomass, respectively. In order to remove these metal ions by the activated Azolla, the enthalpy change ({delta}H) was -4.403, -4.495, -4.557 and -4.365 kcal/mol and the entropy change ({delta}S) was 2.290, 1.268, 1.745 and 1.006 cal/mol K, respectively. While, to remove these metal ions by the non-activated Azolla, {delta}H was -3.685, -3.766, -3.967 and -3.731 kcal/mol and {delta}S was 2.440, 1.265, 1.036 and 0.933 cal/mol K, respectively. On the other hand, the living Azolla removed these heavy metals corresponding to first-order kinetic model. It was also shown that pH, temperature and photoperiod were effective both on the rate of Azolla growth and the rate of heavy metals uptake during 10 days. It was appeared the use of Ca(NO{sub 3}){sub 2} increased both Azolla growth rate and the rate of heavy metals uptake while the using KNO{sub 3} although increased Azolla growth rate but decreased the rate of heavy metals uptake.

Valorisation de Azolla spp, Moringa oleifera, son de riz, et de co ...

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SARAH

FAST)/ Université d'Abomey- .... la production de viande (Figueroa and Ly, 1990). ..... International Conference on Sustainable Food ... Azolla-Anabaena's behaviour in urban .... characteristics and consumer preference of.

Influence of an azolla layer on growth, production and efficiency and use of 15N Labelled urea fertilizer of lowland rice

International Nuclear Information System (INIS)

Hendrarti, Etty; Sopandie, Didy; Komarudin Idris; Sisworo, Elsje L

1998-01-01

The purpose of this experiment was to study the effect of an Azolla mat on rice growth, percentage of N-total, N derived from fertilizer and urea efficiency. The experiment used a factorial design which consists of 2 factors : the using of an Azolla mat and the doses of N fertilizer. The first factor comprised 2 levels, with (A1) and without an azolla mat (A0). The second factor comprised 4 levels, 0(N0), 30 (N1), 60(N2) and 90 kg N/ha(N3).Application of 15 N labeled Urea done to determine percentage N-derived from Urea efficiency , which was divided in 2 experiment series as follows : application Urea at planting (experiment I) and one month after planting (experiment II). The experiments were carried out in the green house of Agricultural Faculty of IPB and continued in the laboratory of BATAN. Parameters observed were plant height, number of tillers, number of panicles, number of grains/panicle, dry weight of grain, straw and percentage of empty grain. Result of the experiment showed that an Azolla mat, the doses of N fertilizer and interaction of both increased all the parameters observed yield, except for percentage of empathy grain, up to the dose of N fertilizer at 60 kg N/ha and decreased at the dose of N fertilizer at 90 kg N/ha. The treatment of Urea fertilizer doses resulted in a significant difference on the percentage of N- derived from Urea for both experiment, but not for the treatment of an Azolla mat and the interaction of both treatment. An azolla mat, N fertilizer and interaction of both did not result in a significantly difference on the percentage of total-N and Urea efficiency. The best treatment combination was treatment of an azolla mat and dose of Urea fertilizer of 60 kg N/ha. (author)

Pre-treatment processes of Azolla filiculoides to remove Pb(II), Cd(II), Ni(II) and Zn(II) from aqueous solution in the batch and fixed-bed reactors.

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Khosravi, Morteza; Rakhshaee, Roohan; Ganji, Masuod Taghi

2005-12-09

Intact and treated biomass can remove heavy metals from water and wastewater. This study examined the ability of the activated, semi-intact and inactivated Azolla filiculoides (a small water fern) to remove Pb(2+), Cd(2+), Ni(2+) and Zn(2+) from the aqueous solution. The maximum uptake capacities of these metal ions using the activated Azolla filiculoides by NaOH at pH 10.5 +/- 0.2 and then CaCl(2)/MgCl(2)/NaCl with total concentration of 2 M (2:1:1 mole ratio) in the separate batch reactors were obtained about 271, 111, 71 and 60 mg/g (dry Azolla), respectively. The obtained capacities of maximum adsorption for these kinds of the pre-treated Azolla in the fixed-bed reactors (N(o)) were also very close to the values obtained for the batch reactors (Q(max)). On the other hand, it was shown that HCl, CH(3)OH, C(2)H(5)OH, FeCl(2), SrCl(2), BaCl(2) and AlCl(3) in the pre-treatment processes decreased the ability of Azolla to remove the heavy metals in comparison to the semi-intact Azolla, considerably. The kinetic studies showed that the heavy metals uptake by the activated Azolla was done more rapid than those for the semi-intact Azolla.

Is there foul play in the leaf pocket? The metagenome of floating fern Azolla reveals endophytes that do not fix N2 but may denitrify.

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Dijkhuizen, Laura W; Brouwer, Paul; Bolhuis, Henk; Reichart, Gert-Jan; Koppers, Nils; Huettel, Bruno; Bolger, Anthony M; Li, Fay-Wei; Cheng, Shifeng; Liu, Xin; Wong, Gane Ka-Shu; Pryer, Kathleen; Weber, Andreas; Bräutigam, Andrea; Schluepmann, Henriette

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla ferns were characterized. A metagenomic approach was taken complemented by detection of N 2 O released and nitrogen isotope determinations of fern biomass. Ribosomal RNA genes in sequenced DNA of natural ferns, their enriched leaf pockets and water filtrate from the surrounding ditch established that bacteria of A. filiculoides differed entirely from surrounding water and revealed species of the order Rhizobiales. Analyses of seven cultivated Azolla species confirmed persistent association with Rhizobiales. Two distinct nearly full-length Rhizobiales genomes were identified in leaf-pocket-enriched samples from ditch grown A. filiculoides. Their annotation revealed genes for denitrification but not N 2 -fixation. 15 N 2 incorporation was active in ferns with N. azollae but not in ferns without. N 2 O was not detectably released from surface-sterilized ferns with the Rhizobiales. N 2 -fixing N. azollae, we conclude, dominated the microbiome of Azolla ferns. The persistent but less abundant heterotrophic Rhizobiales bacteria possibly contributed to lowering O 2 levels in leaf pockets but did not release detectable amounts of the strong greenhouse gas N 2 O. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Arctic Ocean circulation during the anoxic Eocene Azolla event

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Speelman, Eveline; Sinninghe Damsté, Jaap; März, Christian; Brumsack, Hans; Reichart, Gert-Jan

2010-05-01

The Azolla interval, as encountered in Eocene sediments from the Arctic Ocean, is characterized by organic rich sediments ( 4wt% Corg). In general, high levels of organic matter may be caused by increased productivity, i.e. extensive growth of Azolla, and/or enhanced preservation of organic matter, or a combination of both. Anoxic (bottom) water conditions, expanded oxygen minimum zones, or increased sedimentation rates all potentially increase organic matter preservation. According to plate tectonic, bathymetric, and paleogeographic reconstructions, the Arctic Ocean was a virtually isolated shallow basin, with one possible deeper connection to the Nordic Seas represented by a still shallow Fram Strait (Jakobsson et al., 2007), hampering ventilation of the Arctic Basin. During the Azolla interval surface waters freshened, while at the same time bottom waters appear to have remained saline, indicating that the Arctic was highly stratified. The restricted ventilation and stratification in concert with ongoing export of organic matter most likely resulted in the development of anoxic conditions in the lower part of the water column. Whereas the excess precipitation over evaporation maintained the freshwater lid, sustained input of Nordic Sea water is needed to keep the deeper waters saline. To which degree the Arctic Ocean exchanged with the Nordic Seas is, however, still largely unknown. Here we present a high-resolution trace metal record (ICP-MS and ICP-OES) for the expanded Early/Middle Eocene section capturing the Azolla interval from Integrated Ocean Drilling Program (IODP) Expedition 302 (ACEX) drilled on the Lomonosov Ridge, central Arctic Ocean. Euxinic conditions throughout the interval resulted in the efficient removal of redox sensitive trace metals from the water column. Using the sedimentary trace metal record we also constrained circulation in the Arctic Ocean by assessing the relative importance of trace metal input sources (i.e. fluvial, eolian, and

Alien and exotic Azolla in northern Iran | Hashemloian | African ...

African Journals Online (AJOL)

Azolla filiculoides a planktonic fern found floating on the surface of wetlands, ponds and rivers. Because of its ability to fix nitrogen through symbiotic cyanobacteria, it causes more rice production in paddy fields and is used as a green fertilizer. A. filiculoides was introduced from Philippine as a green fertilizer for rice crop to ...

Improvement Bio sorption of Heavy Metals from Industrial Wastewater Using Azolla

International Nuclear Information System (INIS)

Kotb, E.A.

2012-01-01

This study aims to improve the removal process which is vital for some heavy metals and natural radionuclides from industrial wastewater by bio sorption using living organisms with rapid growth as a trial to increase the efficient use of those organisms in the removal process is vital for the toxic elements. Bio sorption of heavy metal (Copper, Manganese, Iron, Zinc, Lead and Strontium) from industrial waste water (contaminated) with six different time periods for Azolla growth. The results indicate that Azolla plant able to on the absorption of ions of heavy elements and Sr and was up to the maximum absorption of most of the elements at a concentration of 50% of polluted water + 50% fresh water so we recommend using the plant Azolla as bio sorbent in the disposal and collection of heavy metals and radionuclides from industrial waste water and deal with it safely to humans and the environment. The results obtained confirm the ability of the fern to grow and absorb ion of heavy metal when mixed with industrial waste water and other sources of polluted water and act as bio filter. The optimum conditions for maximum removal of heavy metals were also determined. Study was conducted on recycling municipal wastewaters for cultivation of Azollamicrophylla biomass, which is used for inoculation into paddy fields as N bio fertilizer and has other applications as green manure,animal feed and bio filter.

Potential of some aquatic plants for removal of arsenic from wastewater by green technology

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Mohammed Barznji Dana A.

2015-03-01

Full Text Available Phytoremediation or green technology is counted among the successful and effective biological contaminated water treatment techniques. Basically, the concept of this green, cost-effective, simple, environmentally nondisruptive method consists in using plants and microbiological processes to reduce contaminants in the ecosystem. Different species from aquatic plants (emerged, free-floating, and submerged have been studied to mitigate toxic contaminants such as arsenic, cadmium, chromium, copper, lead, mercury, zinc, etc. Arsenic is one of the most severe toxic elements; it is widely distributed in the environment, usually found in combination with chloride, oxygen, sulphur and metal ions as a result of mineral dissolution from sedimentary or volcanic rocks and the dilution of geothermal water. The effluents from both industrial and agricultural sectors are also regarded as sources to contaminate water. From the accumulation point of view, several aquatic plants have been mentioned as good arsenic accumulators and their performance is evaluated using the green technology method. These include Spirodela polyrhiza, Wolffia globosa, Lemna gibba, L. minor, Eichhornia crassipes, Azolla caroliniana, Azolla filiculoides, Azolla pinnata, Ceratophyllum demersum and Pistia stratiotes. The up-to-date information illustrated in this review paper generates knowledge about the ability of some common aquatic plants around the globe to remediate arsenic from contaminated water.

Biology and preliminary host range of Hydrotimetes natans Kolbe (Coleoptera:Curculionidae)a natural enemy candidate for biological control of Cabomba caroliniana Gray (Cabombaceae) in Australia

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Cabomba caroliniana Gray (Cabombaceae), otherwise known as cabomba or water fanwort, is a submerged, rooted macrophyte with heavily dissected leaves that produces flowers that extend above the water’s surface. It has been disseminated around the world through the aquarium trade and has become a nox...

Agronomic efficiency and physiologic efficiency determination of Azolla-N and Urea-N applied to lowland rice

International Nuclear Information System (INIS)

Sisworo, Elsje L.; Rasjid, Havid; Sisworo, Widjang H.; Wemay, Johannis; Djawanas, Amrin

1994-01-01

Data from three field experiments using 15 N labelled Azolla and urea as an N source have been used to determine the agronomical and physiological efficiency of the N-Azoll and N-Urea applied tolowland rice. In general physiological efficiency of N from N-sources applied was lower than the agronomical efficiency. It seems that the increase of N-rates would enhance the agronomical and physiological efficiency of N applied to lowland rice but on the other hand the efficiency of N derived from the applied N-source decreased. Azolla+inorganic N-fertilizer when applied to lowland rice could increase rice yield expresses in dry weight of grain and straw above the control plants. Applying Azolla+inorganic N-fertilizer in the farmer's field located in West Java and West Sumatera often showed higher yields compared to when applied with inorganic N-fertilizer alone although the latter has higher total N-rates. (author). 9 refs, 8 tabs, 5 figs

Investigation of Pb(II Removal from Synthetic Wastewater by Using Azolla Filiculoides Biomass

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Davoud Balarak

2015-06-01

Full Text Available Background and Aim: Discharge of industrial wastewater containing Pb into the environment can have harmful effects in the live organisms. Therefore, Pb must be removed from polluted water using an effective method before being discharged into the environment. The purpose of the present study was to examine Pb removal using alga Azolla biomass. Materials and Methods: In this experimental study, removal of Pb(II was performed using Azolla biomass considering changes in time, pH, adsorbent dose, initial concentration of Pb and mixing speed. Experiments were performed in batch reactor in flasks on Shaker. , Atomic absorption spectrophotometry was used for Pb determination. All experiments were conducted in triplicate and the mean removal percent was reported. Finally, biosorption kinetic and equilibrium isotherms of adsorbent was investigated. Results: It was found that the higher removal efficiency of Pb occurred in pH 6 and aoptimum dsorbent dose 7 g/L. With increase in the initial concentration of Pb, removal efficincy decreased and with increasing of contact time and mixing speed,efficincy increased. Data also showed that the Langmuir isotherm and pseudo second-order kinetic are compliance. Conclusion: Azolla biomass is an efficient and low-cost adsorbent for removing of Pb (II from water and wastewater.

Application of Azolla for 2-Chlorophenol and 4-Chrorophenol Removal from Aqueous Solutions

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Mohammad Ali Zazouli

2013-09-01

Full Text Available Background and purpose: The 2-chlorophenol (2-CP and 4-chlorophenol (4-CP are phenolic compounds which may have adverse effects on human and environment. Therefore, removing these compounds from water and wastewater is necessary. This study aims to analyze 2-CP and 4-CP removal by using Azolla filiculoides biomass. Materials & Methods: Azolla biomass was sun dried, crushed and sieved to particle sizes ranging 1-2 mm. Then it was treated with 0.1M HCl for 5h followed by washing with distilled water and it was used as adsorbent. The residues concentration of 2-CP and 4-CP was measured by spectrophotometer in λmax of 274 and 280 nm, respectively. Results: The solute removed increases as contact time rises. The equilibrium time for 2-CP and 4-CP is 90 and 75, respectively. The removal efficiency of 4-CP is more than 2-CP. An increase in initial concentration of both compounds can lead to decrease of their removal efficiency. The optimum pH to remove both compounds is 5. The equilibrium data matched best on Freundlich isotherm and the adsorption kinetic model follows pseudo-second model. Conclusion: The results indicated that Azolla is an effective adsorbent for removing 2-CP and 4-CP from water and wastewater.

Palaeoecological and palaeoclimatological implications of the Eocene Northern Hemisphere Azolla phenomenon

NARCIS (Netherlands)

Barke, J.

2010-01-01

The high abundances and cyclic distribution of remains of the freshwater fern Azolla in early middle Eocene sediments from the Arctic Ocean have previously been related to episodic surface water freshening, which was speculated to be orbitally modulated. Our integrated palynological and

Factors regulating nitrogenase activity and hydrogen evolution in Azolla-Anabaena symbiosis

Energy Technology Data Exchange (ETDEWEB)

Banerjee, M.; Kumar, A.; Kumar, H.D. (Banaras Hindu Univ., Varanasi (India). Dept. of Botany)

1989-01-01

Nitrogenase activity and H{sub 2} production capacity have been studied in intact Azolla plants. Under aerobic conditions the plants showed a C{sub 2}H{sub 2} reduction rate of 6.65 nmoles C{sub 2}H{sub 4} mg {sup -1} fresh weight in light at 48 h. Considerable activity was also present in the dark. Though H{sub 2} evolution was detected under aerobic conditions there was multifold stimulation under anaerobic conditions. There was no significant change in nitrogenase activity under anaerobic conditions. Increasing concentrations of O{sub 2} inhibited nitrogenase activity but 5% O{sub 2} proved stimulatory for H{sub 2} evolution in light. In the dark, there was a gradual stimulation in H{sub 2} evolution even up to 20% O{sub 2}. The addition of combined nitrogen sources, namely NH{sub 4}Cl or KNO{sub 3} (10 mM), resulted in complete inhibition of the C{sub 2}H{sub 2}-reduction activity within 48 h, but H{sub 2} evolution was not inhibited. Indeed, these combined nitrogen sources stimulated H{sub 2} evolution. Though nitrogenase activity was affected, the heterocyst frequency remained unaltered. Phosphate addition resulted in significant stimulation of nitrogenase and H{sub 2} evolution activity. These results suggest that nitrogenase and H{sub 2} evolution activity in Azolla are affected by a number of factors which show a differential effect on nitrogenase and H{sub 2} evolution. Furthermore, our results indicate the presence of a soluble reversible hydrogenase in Azolla. (author).

Inhibition of nitrogen-fixing activity of the cyanobiont affects the localization of glutamine synthetase in hair cells of Azolla.

Science.gov (United States)

Uheda, Eiji; Maejima, Kazuhiro

2009-10-15

In the Azolla-Anabaena association, the host plant Azolla efficiently incorporates and assimilates ammonium ions that are released from the nitrogen-fixing cyanobiont, probably via glutamine synthetase (GS; EC 6.3.1.2) in hair cells, which are specialized cells protruding into the leaf cavity. In order to clarify the regulatory mechanism underlying ammonium assimilation in the Azolla-Anabaena association, Azolla plants were grown under an argon environment (Ar), in which the nitrogen-fixing activity of the cyanobiont was inhibited specifically and completely. The localization of GS in hair cells was determined by immunoelectron microscopy and quantitative analysis of immunogold labeling. Azolla plants grew healthily under Ar when nitrogen sources, such as NO(3)(-) and NH(4)(+), were provided in the growth medium. Both the number of cyanobacterial cells per leaf and the heterocyst frequency of the plants under Ar were similar to those of plants in a nitrogen environment (N(2)). In hair cells of plants grown under Ar, regardless of the type of nitrogen source provided, only weak labeling of GS was observed in the cytoplasm and in chloroplasts. In contrast, in hair cells of plants grown under N(2), abundant labeling of GS was observed in both sites. These findings indicate that specific inhibition of the nitrogen-fixing activity of the cyanobiont affects the localization of GS isoenzymes. Ammonium fixed and released by the cyanobiont could stimulate GS synthesis in hair cells. Simultaneously, the abundant GS, probably GS1, in these cells, could assimilate ammonium rapidly.

Responses of the nitrogen-fixing aquatic fern Azolla to water contaminated with ciprofloxacin: Impacts on biofertilization.

Science.gov (United States)

Gomes, Marcelo Pedrosa; de Brito, Júlio César Moreira; Carvalho Carneiro, Marília Mércia Lima; Ribeiro da Cunha, Mariem Rodrigues; Garcia, Queila Souza; Figueredo, Cleber Cunha

2018-01-01

We investigated the ability of the aquatic fern Azolla to take up ciprofloxacin (Cipro), as well as the effects of that antibiotic on the N-fixing process in plants grown in medium deprived (-N) or provided (+N) with nitrogen (N). Azolla was seen to accumulate Cipro at concentrations greater than 160 μg g -1 dry weight when cultivated in 3.05 mg Cipro l -1 , indicating it as a candidate for Cipro recovery from water. Although Cipro was not seen to interfere with the heterocyst/vegetative cell ratios, the antibiotic promoted changes with carbon and nitrogen metabolism in plants. Decreased photosynthesis and nitrogenase activity, and altered plant's amino acid profile, with decreases in cell N concentrations, were observed. The removal of N from the growth medium accentuated the deleterious effects of Cipro, resulting in lower photosynthesis, N-fixation, and assimilation rates, and increased hydrogen peroxide accumulation. Our results shown that Cipro may constrain the use of Azolla as a biofertilizer species due to its interference with nitrogen fixation processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Application of AzollaFiliculoides Biomass in Acid Black 1 Dye Adsorption from Aqueous Solution

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Mohammad Ali Zazouli

2014-09-01

Full Text Available Background and purpose: The textile dyes are considered as important pollutants due to the toxicity on human and environment. Therefore, the dye removal from industrial effluents is necessary. This study evaluates the ability of Azolla for the adsorption of acid black 1 (AB1 dye from aqueous solution. Materials and Methods: This was an experimental-laboratory study. The Azolla biomass was sun dried, crushed and sieved to particle sizes in the range of 1-2 mm. Then, it treated with 0.1 M HCl for 5 h, followed by washing with distilled water, and it used as an adsorbent. The effect of study parameter was investigated, and the residues AB1 concentration was measured by DR2800 spectrophotometer at in λmax = 622 nm. Results: The results indicated that the efficiency of AB1 adsorption decreased with increased initial dye concentration. It increased with increased contact time and adsorbent. The highest adsorption efficiency was occurred at pH = 2. The equilibrium data were the best fitted on Langmuir isotherm and pseudo-second-order kinetic model. Conclusion: The Azolla could present high ability in dye removal. Therefore, it can be used as inexpensive and effective adsorbent in textile effluent treatment.

Pemberian Kombinasi Pupuk Hijau Azolla Pinnata Dengan Pupuk Guano Terhadap Pertumbuhan Dan Produksi Tanaman Pakchoy (Brassica Chinensis L.)

OpenAIRE

OS, Ozi Nurhasanah; Yetti, Husna; Ariani, Erlida

2015-01-01

This research aimed to look the influence of the combination of green fertilizer Azolla pinnata with guano toward the growth and production of pakchoy and to obtain the best treatment from Azolla pinnata with guano toward pakchoy. This research was conducted at the experimental farm of Farming Faculty of Riau University. This research was accomplished during 3 months that was from June to August 2014. It was carried out experimentally with Group Random Design (GRD), the treatment given which ...

Dynamics of N-NH4 +, N-NO3 -, and total soil nitrogen in paddy field with azolla and biochar

Science.gov (United States)

Dewi, W. S.; Wahyuningsih, G. I.; Syamsiyah, J.; Mujiyo

2018-03-01

Nitrogen (N) is one of macronutrients which is dynamic in the soil and becomes constraint factor for rice crops. The addition of nitrogen fertilizers and its absorption in paddy field causes the dynamics of nitrogen, thus declines of N absorption efficiency. The aim of this research is to know influence Azolla, biochar and different varieties application on N-NH4 +, N-NO3 -, and total soil N in paddy field. This research was conducted in a screen house located in Jumantono Laboratory, Faculty of Agriculture, Universitas Sebelas Maret (UNS) with altitude 170 m asl from April to June 2016. Treatment factors that were examined consisted of azolla (0 and 10 tons/ha), biochar (0 and 2 tons/ha), and rice varieties (Cisadane, Memberamo, Ciherang, IR64). The results of this research showed that there was no interaction between azolla, biochar and varieties. Nevertheless, azolla treatment with dose of 10 tons/ha increased soil NH4 + content (41 days after planting, DAP) by 13.4% but tend to decrease at 70 and 90 DAP. Biochar treatment with dose of 2 ton/ha increases NO3 - soil content (70 DAP) by 1.7% but decreases total N soil by 5.8% (41 DAP) and 4.7% (90 DAP). Different rice varieties generated different soil NH4 + content (41 DAP) and rice root volume. Cisadane variety can increase soil NH4 + content (41 DAP) by 52.08% and root volume by 51.80% (90 DAP) compared with Ciherang variety. Organic rice field management with azolla and biochar affects the availability of N in the soil and increase N absorption efficiency through its role in increasing rice root volume.

Orbitally forced Azolla blooms and Middle Eocene Arctic hydrology: Clues from palynology

NARCIS (Netherlands)

Barke, J.; Abels, H.A.; Sangiorgi, F.; Greenwood, D.R.; Sweet, A.R.; Donders, T.; Reichart, G.-J.; Lotter, A.F.; Brinkhuis, H.

2011-01-01

The high abundances and cyclic distribution of remains of the freshwater fern Azolla in early-Middle Eocene sediments from the Arctic Ocean have previously been related to episodic surface-water freshening, which was speculated to be orbitally modulated. Our integrated palynological and

Orbitally forced Azolla blooms And Middle Eocene Arctic hydrology: Clues from palynology

NARCIS (Netherlands)

Barke, J.; Abels, H.A.; Sangiorgi, F.; Greenwood, D.R.; Sweet, A.R.; Donders, T.; Reichart, G.-J.; Lotter, A.F.; Brinkhuis, H.

2011-01-01

The high abundances and cyclic distribution of remains of the freshwater fern Azolla in early-Middle Eocene sediments from the Arctic Ocean have previously been related to episodic surface-water freshening, which was speculated to be orbitally modulated. Our integrated palynological and

Alimentation des lapins ( Oryctolagus cuniculus L.) à base de Azolla ...

African Journals Online (AJOL)

Les systèmes intégrés de production constituent l'une des voies essentielles pour une agriculture durable. Cette étude a pour but d'évaluer l'effet d'une alimentation à base de Azolla filiculoïdes, Elaeis guineensis, Ipomoea aquatica et Panicum maximum sur les performances zootechniques des lapins et le potentiel nutritif ...

Limited Multiplication of Symbiotic Cyanobacteria of Azolla spp. on Artificial Media

Science.gov (United States)

Tang, L. F.; Watanabe, I.; Liu, C. C.

1990-01-01

We examined various media and conditions to isolate symbiotic cyanobacteria from the leaf cavities of Azolla spp. Cyanobacteria survived and multiplied to a limited extent on a medium with fructose, Casamino Acids, yeast extract, and NaNO3 under 1% O2. These cyanobacteria were antigenically identical to the endosymbionts. Images PMID:16348366

Evaluating the combined effects of pretilachlor and UV-B on two Azolla species.

Science.gov (United States)

Prasad, Sheo Mohan; Kumar, Sushil; Parihar, Parul; Singh, Anita; Singh, Rachana

2016-03-01

The present study assessed the comparative responses of two agronomic species of Azolla (A.microphylla and A. pinnata) exposed to man-made and natural stressors by evaluating biomass accumulation, pigments (chlorophyll a and b and carotenoid contents), photosynthetic activity and nitrogen metabolism. The study was carried out in field where two species of Azolla were cultured and treated with various concentrations (5, 10 and 20 μg ml(-1)) of herbicide; pretilachlor [2-chloro-2,6-diethyl-N-(2-propoxyethyl) acetanilide] and enhanced levels (UV-B1: ambient +2.2 kJ m(-2) day(-1) and UV-B2: ambient +4.4 kJ m(-2) day(-1)) of UV-B, alone as well as in combination. Biomass accumulation, photosynthetic pigments; chlorophyll a, b and carotenoids, photosynthetic oxygen yield and photosynthetic electron transport activities i.e. photosystem II (PS II) and photosystem I (PS I) in both the species declined with the increasing doses of pretilachlor and UV-B radiation, which further declined when applied in combination. The lower doses (5 and 10 μg ml(-1)) of pretilachlor and UV-B (UV-B1 and UV-B2) alone, damaged mainly the oxidation side of PS II, whereas higher dose (20 μg ml(-1)) of pretilachlor alone and in combination with UV-B1 and UV-B2 caused damage to PS II reaction centre and beyond this towards the reduction side. A significant enhancement in respiration was also noticed in fronds of both the Azolla species following pretilachlor and UV-B treatment, hence indicating strong damaging effect. The nitrate assimilating enzymes - nitrate reductase and nitrite reductase and ammonium assimilating enzymes - glutamine synthetase and glutamate synthase were also severely affected when treated either with pretilachlor and/or UV-B while glutamate dehydrogenase exhibited a stimulatory response. The study suggests that both the species of Azolla showed considerable damage under pretilachlor and UV-B treatments alone, however, in combination the effect was more intense. Further, in

Azolla pinnata growth performance in different water sources.

Science.gov (United States)

Nordiah, B; Harah, Z Muta; Sidik, B Japar; Hazma, W N Wan

2012-07-01

Azolla pinnata R.Br. growth performance experiments in different water sources were conducted from May until July 2011 at Aquaculture Research Station, Puchong, Malaysia. Four types of water sources (waste water, drain water, paddy field water and distilled water) each with different nutrient contents were used to grow and evaluate the growth performance of A. pinnata. Four water sources with different nutrient contents; waste, drain, paddy and distilled water as control were used to evaluate the growth performance of A. pinnata. Generally, irrespective of the types of water sources there were increased in plant biomass from the initial biomass (e.g., after the first week; lowest 25.2% in distilled water to highest 133.3% in drain water) and the corresponding daily growth rate (3.61% in distilled water to 19.04% in drain water). The increased in biomass although fluctuated with time was consistently higher in drain water compared to increased in biomass for other water sources. Of the four water sources, drain water with relatively higher nitrate concentration (0.035 +/- 0.003 mg L(-l)) and nitrite (0.044 +/- 0.005 mg L(-1)) and with the available phosphate (0.032 +/- 0.006 mg L(-1)) initially provided the most favourable conditions for Azolla growth and propagation. Based on BVSTEP analysis (PRIMER v5), the results indicated that a combination of more than one nutrient or multiple nutrient contents explained the observed increased in biomass of A. pinnata grown in the different water sources.

The Contribution of Azolla and Urea in Lowland Rice Growth Production for Three Consecutive Seasons

International Nuclear Information System (INIS)

E-L-Sisworo; H-Rasjid; Haryanto; Idawati

2008-01-01

Three field experiments have been carried out in three consecutive seasons namely wet season (120 days), dry season (120 days), wet season (120 days) at Pusakanegara. The purpose of this experiment is to test whether urea combined with Azolla could increase lowland rice production and soil quality. The experimental plots have a size of 20 m 2 and in each experimental plot an isotope plot was placed with a size of 1 m 2 . The isotope plots were used to apply labeled 15 N urea. Treatments conducted were lowland varieties: Atomita I (V1) and IR-64 (V2); several levels of urea and Azolla : Pu1 urea-tablets + an Azolla cover (Azc), Pu2 = urea-tablets + Azolla incorporated (Azi ), Pu3 = urea-prill + Azc , Pu4 = urea-prill + Azi; seasons : Ss 1 = wet season, Ss2 = dry season, Ss3 = wet season. The experimental design used was a factorial experiment in a Randomized Block Design, where each treatment was replicated four times. Parameters used were, dry weight of straw (St), grain (G), plant (P1 = St + G) in kg/ha; N-total percentage (% N-to) of St and G, percentage N-derived from urea + Az (% N-Pu) of St and G; percentage N-derived from soil (% N-S) of St and G; uptake of N-Pu and N-S in St, G and P1. Some results of these experiment were, N-Pu play a less important role in growth of lowland crop expressed in several parameters compared to N-soil. The form of N-urea in tablets are superior to that the form of urea in prills. For the last product of lowland rice which is grain obviously V1 (Atomita-1) is better than V2 (IR-64) expressed in t/ha. The progress of seasons showed clearly that there is an N accumulation which might be the increase of soil organic matter (SOM) and that means there is an increase in soil quality in the view point of N. (author)

The Contribution of Azolla and Urea in Lowland Rice Growth Production for Three Consecutive Seasons

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EL. Sisworo

2008-01-01

Full Text Available Three field experiments have been carried out in three consecutive seasons namely wet season (120 days, dry season (120 days, wet season (120 days at Pusakanegara. The purpose of this experiment is to test whether urea combined with Azolla could increase lowland rice production and soil quality. The experimental plots have a size of 20 m2 and in each experimental plot an isotope plot was placed with a size of 1 m2. The isotope plots were used to apply labeled 15N urea. Treatments conducted were lowland varieties: Atomita I (V1 and IR-64 (V2; several levels of urea and Azolla : Pu1 = urea-tablets + an Azolla cover (Azc, Pu2 = urea-tablets + Azolla incorporated (Azi , Pu3 = urea-prill + Azc , Pu4 = urea-prill + Azi; seasons : Ss 1 = wet season, Ss2 = dry season, Ss3 = wet season. The experimental design used was a factorial experiment in a Randomized Block Design, where each treatment was replicated four times. Parameters used were, dry weight of straw (St, grain (G, plant (P1 = St + G in kg/ha; N-total percentage (% N-to of St and G, percentage N-derived from urea + Az (% N-Pu of St and G; percentage N-derived from soil (% N-S of St and G; uptake of N-Pu and N-S in St, G and P1. Some results of these experiment were, N-Pu play a less important role in growth of lowland crop expressed in several parameters compared to N-soil. The form of N-urea in tablets are superior to that the form of urea in prills. For the last product of lowland rice which is grain obviously V1 (Atomita-1 is better than V2 (IR-64 expressed in t/ha. The progress of seasons showed clearly that there is an N accumulation which might be the increase of soil organic matter (SOM and that means there is an increase in soil quality in the view point of N

Sensitivity of aquatic organisms to ethanol and its potential use as bioindicators

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Adilson Ferreira Silva

2016-12-01

Full Text Available The aim of this research was to evaluate the feasibility for the use of the organisms Lemna minor, Azolla caroliniana, Hyphessobrycon eques, Pomacea canaliculata and Daphnia magna as exposure bioindicators for ethanol (lethal and effective concentration 50% - LC50(I/EC50(I. Thus, the following concentrations were used 5.0; 10.0; 20.0; 30.0; 40.0 and 50.0 mg L-1 ethanol on L. minor; 25.0; 50.0; 75.0; 100.0; 150.0 and 200.0 mg L-1 on A. caroliniana; 0.3; 0.5; 1.0; 2.0 and 3.0 mg L-1 on H. eques; 0.05; 0.10; 0.20; 0.40 and 0.80 mg L-1 on P. canaliculata; and 40.0; 60.0; 80.0; 100.0; 120.0 and 140.0 mg L-1 on D. magna. An untreated control was also kept for all organisms, with three repetitions. The increase in the ethanol concentration elevated the electrical conductivity and decreased the water dissolved oxygen and pH. The ethanol LC50 for L. minor and A. caroliniana were 12.78 and 73.11 mg L-1, respectively, and was classified as slightly toxic; 1.22 mg L-1 for H. eques (moderately toxic; 0.39 mg L-1 for P. canaliculata (highly toxic and 98.85 mg L-1 for D. magna (slightly toxic. Thus, H. eques and P. canaliculata have showed good potential for the use as ethanol exposure bioindicators on water bodies.

Effect of feeding different levels of Azolla pinnata on blood biochemicals, hematology and immunocompetence traits of Chabro chicken.

Science.gov (United States)

Mishra, Deepesh Bharat; Roy, Debashis; Kumar, Vinod; Bhattacharyya, Amitav; Kumar, Muneendra; Kushwaha, Raju; Vaswani, Shalini

2016-02-01

The present study was conducted to see the effect of feeding different levels of Azolla meal on blood biochemicals, hematology and immunocompetence traits of Chabro chicken. The study was conducted on 160 Chabro chicks, which were randomly divided into four treatment groups each with four replicates of 10 birds. The first treatment (T1) served as a control in which basal diets was offered without Azolla supplementation while in T2, T3, and T4 groups, basal diet was replaced with Azolla meal at 5%, 7.5%, and 10% levels, respectively. A feeding trial was conducted upto 8 weeks. At the last week of trial, blood samples were collected randomly from one bird of each replicate and plasma was separated to estimate certain biochemical parameters, some blood metabolites, minerals and enzymes like alanine aminotransferase and aspartate aminotransferase (AST). Hematological parameters such as hemoglobin, packed cell volume, total leukocytes count and differential leukocytes count were estimated in fresh blood just after collection. The humoral immune response was measured against sheep red blood cells,and cell-mediated immune response was measured against phyto hemagglutinin lectin from Phaseolus vulgaris (PHA-P). The study showed that hematological profile of the Chabro bird was not affected by any treatment except heterophil and lymphocyte which was found higher in T2 and T3 groups and eosinophil was found higher in a T3 group than control. Blood glucose, creatinine, cholesterol, total protein, albumin, uric acid, and triglycerides were found similar in all the groups and within the normal values for broiler chicken. Liver enzymes and macro mineral content in blood were found similar in all the treatment groups and within normal physiological range. Although AST was found higher in 10% replacement group than control, the value was within normal range for broiler chicken. Although antibody titer was found similar in all the experimental groups in the present study, cell

Effect of feeding different levels of Azolla pinnata on blood biochemicals, hematology and immunocompetence traits of Chabro chicken

Directory of Open Access Journals (Sweden)

Deepesh Bharat Mishra

2016-02-01

Full Text Available Aim: The present study was conducted to see the effect of feeding different levels of Azolla meal on blood biochemicals, hematology and immunocompetence traits of Chabro chicken. Materials and Methods: The study was conducted on 160 Chabro chicks, which were randomly divided into four treatment groups each with four replicates of 10 birds. The first treatment (T1 served as a control in which basal diets was offered without Azolla supplementation while in T2, T3, and T4 groups, basal diet was replaced with Azolla meal at 5%, 7.5%, and 10% levels, respectively. A feeding trial was conducted upto 8 weeks. At the last week of trial, blood samples were collected randomly from one bird of each replicate and plasma was separated to estimate certain biochemical parameters, some blood metabolites, minerals and enzymes like alanine aminotransferase and aspartate aminotransferase (AST. Hematological parameters such as hemoglobin, packed cell volume, total leukocytes count and differential leukocytes count were estimated in fresh blood just after collection. The humoral immune response was measured against sheep red blood cells,and cell-mediated immune response was measured against phyto hemagglutinin lectin from Phaseolus vulgaris (PHA-P. Results: The study showed that hematological profile of the Chabro bird was not affected by any treatment except heterophil and lymphocyte which was found higher in T2 and T3 groups and eosinophil was found higher in a T3 group than control. Blood glucose, creatinine, cholesterol, total protein, albumin, uric acid, and triglycerides were found similar in all the groups and within the normal values for broiler chicken. Liver enzymes and macro mineral content in blood were found similar in all the treatment groups and within normal physiological range. Although AST was found higher in 10% replacement group than control, the value was within normal range for broiler chicken. Although antibody titer was found similar in all

Modulation of physiological responses with TiO2 nano-particle in Azolla pinnata R.Br. under 2,4-D toxicity.

Science.gov (United States)

De, Arnab Kumar; Ghosh, Arijit; Debnath, Subhas Chandra; Sarkar, Bipul; Saha, Indraneel; Adak, Malay Kumar

2018-06-05

The present work is emphasised with the herbicidal tolerance of Azolla pinnata R.Br. and its modulation with TiO 2 nano-particle. Both carbohydrate and nitrogen metabolism were effected with 2,4-D as herbicide and in few cases TiO 2 -NP had recovered few detrimental effects. From the nutrient status in Azolla it recorded the recovery of nitrogen as well as potassium by TiO 2 -NP but not in case of phosphorus. However, a conversion of nitrate to ammonium was more induced by TiO 2 -NP under herbicidal toxicity. Similar results were obtained for inter-conversion of amino acid-nitrate pool, but no changes with glutamine synthase activity with TiO 2 -NP. Initially, the effects of 2,4-D was monitored with changes of chlorophyll content but had not been recovered with nanoparticle. Photosynthetic reserves expressed as both total and reducing sugar were insensitive to TiO 2 -NP interference but activity of soluble and wall bound invertase was in reverse trend as compared to control. The 2,4-D mediated changes of redox and its oxidative stress was ameliorated in plants with over expressed ADH activity. As a whole the Azolla bio system with TiO 2 supplementation may be useful in sustenance against 2,4-D toxicity through recovery of nitrogen metabolism. Thus, Azolla-TiO 2 -NP bio system would be realised to monitor the herbicidal toxicity in soil and its possible bioremediation.

Azolla along a phosphorus gradient: biphasic growth response linked to diazotroph traits and phosphorus-induced iron chlorosis.

Science.gov (United States)

Temmink, Ralph J M; Harpenslager, Sarah F; Smolders, Alfons J P; van Dijk, Gijs; Peters, Roy C J H; Lamers, Leon P M; van Kempen, Monique M L

2018-03-13

Azolla spp., a water fern often used for phytoremediation, is a strong phosphorus (P) accumulator due to its high growth rate and N 2 fixing symbionts (diazotrophs). It is known that plant growth is stimulated by P, but the nature of the interactive response of both symbionts along a P gradient, and related changes in growth-limiting factors, are unclear. We determined growth, and N and P sequestration rates of Azolla filiculoides in N-free water at different P concentrations. The growth response appeared to be biphasic and highest at levels ≥10 P µmol l -1 . Diazotrophic N sequestration increased upon P addition, and rates were three times higher at high P than at low P. At 10 µmol P l -1 , N sequestration rates reached its maximum and A. filiculoides growth became saturated. Due to luxury consumption, P sequestration rates increased until 50 µmol P l -1 . At higher P concentrations (≥50 µmol l -1 ), however, chlorosis occurred that seems to be caused by iron- (Fe-), and not by N-deficiency. We demonstrate that traits of the complete symbiosis in relation to P and Fe availability determine plant performance, stressing the role of nutrient stoichiometry. The results are discussed regarding Azolla's potential use in a bio-based economy.

Aquatic arsenic: phytoremediation using floating macrophytes.

Science.gov (United States)

Rahman, M Azizur; Hasegawa, H

2011-04-01

Phytoremediation, a plant based green technology, has received increasing attention after the discovery of hyperaccumulating plants which are able to accumulate, translocate, and concentrate high amount of certain toxic elements in their above-ground/harvestable parts. Phytoremediation includes several processes namely, phytoextraction, phytodegradation, rhizofiltration, phytostabilization and phytovolatilization. Both terrestrial and aquatic plants have been tested to remediate contaminated soils and waters, respectively. A number of aquatic plant species have been investigated for the remediation of toxic contaminants such as As, Zn, Cd, Cu, Pb, Cr, Hg, etc. Arsenic, one of the deadly toxic elements, is widely distributed in the aquatic systems as a result of mineral dissolution from volcanic or sedimentary rocks as well as from the dilution of geothermal waters. In addition, the agricultural and industrial effluent discharges are also considered for arsenic contamination in natural waters. Some aquatic plants have been reported to accumulate high level of arsenic from contaminated water. Water hyacinth (Eichhornia crassipes), duckweeds (Lemna gibba, Lemna minor, Spirodela polyrhiza), water spinach (Ipomoea aquatica), water ferns (Azolla caroliniana, Azolla filiculoides, and Azolla pinnata), water cabbage (Pistia stratiotes), hydrilla (Hydrilla verticillata) and watercress (Lepidium sativum) have been studied to investigate their arsenic uptake ability and mechanisms, and to evaluate their potential in phytoremediation technology. It has been suggested that the aquatic macrophytes would be potential for arsenic phytoremediation, and this paper reviews up to date knowledge on arsenic phytoremediation by common aquatic macrophytes. Copyright © 2011 Elsevier Ltd. All rights reserved.

Growing Azolla to produce sustainable protein feed: the effect of differing species and CO2 concentrations on biomass productivity and chemical composition.

Science.gov (United States)

Brouwer, Paul; Schluepmann, Henriette; Nierop, Klaas Gj; Elderson, Janneke; Bijl, Peter K; van der Meer, Ingrid; de Visser, Willem; Reichart, Gert-Jan; Smeekens, Sjef; van der Werf, Adrie

2018-03-24

Since available arable land is limited and nitrogen fertilizers pollute the environment, cropping systems ought to be developed that do not rely on them. Here we investigate the rapidly growing, N 2 -fixing Azolla/Nostoc symbiosis for its potential productivity and chemical composition to determine its potential as protein feed. In a small production system, cultures of Azolla pinnata and Azolla filiculoides were continuously harvested for over 100 days, yielding an average productivity of 90.0-97.2 kg dry weight (DW) ha -1  d -1 . Under ambient CO 2 levels, N 2 fixation by the fern's cyanobacterial symbionts accounted for all nitrogen in the biomass. Proteins made up 176-208 g kg -1 DW (4.9 × total nitrogen), depending on species and CO 2 treatment, and contained more essential amino acids than protein from soybean. Elevated atmospheric CO 2 concentrations (800 ppm) significantly boosted biomass production by 36-47%, without decreasing protein content. Choice of species and CO 2 concentrations further affected the biomass content of lipids (79-100 g kg -1 DW) and (poly)phenols (21-69 g kg -1 DW). By continuous harvesting, high protein yields can be obtained from Azolla cultures, without the need for nitrogen fertilization. High levels of (poly)phenols likely contribute to limitations in the inclusion rate of Azolla in animal diets and need further investigation. © 2018 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2018 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Production of biogas from Azolla pinnata R. Br. and Lemna minor L. : effect of heavy metal contamination

Energy Technology Data Exchange (ETDEWEB)

Jain, S K; Gujral, G S; Jha, N K; Vasudevan, P [Indian Inst. of Tech., New Delhi (India)

1992-01-01

The absorption of iron, copper, cadmium, nickel, lead, zinc, manganese and cobalt by Azolla pinnata R.Br and Lemna minor L., and subsequent utilization of this biomass for production of biogas (methane), have been investigated. Iron or manganese did not have any toxic effect on the anaerobic fermentation of Azolla and Lemna, while copper, cobalt, lead and zinc showed toxicity. At low concentrations cadmium and nickel showed a favourable effect on the rate of biogas production and its methane content, but with increase in concentrations,rate of biogas production and methane content decreased. However, although there was this decrease in biogas production and methane content, the methane content of biogas was still higher than that which was obtained from non-contaminated biomass. (author).

Bimodal effect of hydrogen peroxide and oxidative events in nitrite-induced rapid root abscission by the water fern Azolla pinnata.

Science.gov (United States)

Cohen, Michael F; Gurung, Sushma; Birarda, Giovanni; Holman, Hoi-Ying N; Yamasaki, Hideo

2015-01-01

In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H2O2 significantly diminishing the responsiveness to 2 mM NaNO2, and 10 mM H2O2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H2O2, dramatically stimulated root abscission of A. pinnata in response to nitrite, especially for plants previously cultivated in medium containing 5 mM KNO3 compared to plants cultivated under N2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO) from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. We hypothesize that metabolic products of nitrite and NO react with H2O2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission.

Bimodal effect of hydrogen peroxide and oxidative events in nitrite-induced rapid root abscission by the water fern Azolla pinnata

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Michael F Cohen

2015-07-01

Full Text Available In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H2O2 significantly diminishing the responsiveness to 2 mM NaNO2, and 10 mM H2O2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H2O2, dramatically stimulated root abscission of A. pinnata in response to nitrite, especially for plants previously cultivated in medium containing 5 mM KNO3 compared to plants cultivated under N2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared (SR-FTIR spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. We hypothesize that metabolic products of nitrite and NO react with H2O2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission.

Cultivation of Azolla microphylla biomass on secondary-treated Delhi municipal effluents

Energy Technology Data Exchange (ETDEWEB)

Arora, A.; Saxena, S. [Indian Agricultural Research Institute, New Delhi (India). Centre for Conservation of Blue Green Algae

2005-07-01

Study was conducted on recycling municipal wastewaters for cultivation of Azolla microphylla biomass, which is used for inoculation into paddy fields as N biofertiliser and has other applications as green manure, animal feed and biofilter. Secondary-treated municipal wastewaters were collected from Wazirabad sewage treatment plant in New Delhi during all four seasons and tested for reactive P and heavy metal content. The reactive P levels in effluents ranged between 1-2 ppm and levels of heavy metals like Cd, Pb, Ni, Zn, Fe and Mn were well below permissible limits. A. microphylla was grown in sewage effluents and its dilutions prepared with tapwater. It showed good growth potential on sewage effluents. Doubling times during September and December months compared well with those on Espinase and Watanabe (E and W) medium and tapwater. Dried Azolla biomass produced on sewage waters did not show presence of toxic heavy metals Cd, Cr and Pb. However, levels of P in dried biomass cultivated on sewage effluents were lower as compared to those from E and W medium and tapwater. The biomass produced can be used for inoculating paddy fields or for other applications and polished wastewaters can be recycled for irrigation purposes. (author)

Sugar supported H/sub 2/ production and C/sub 2/H/sub 2/ reduction by the cyanobiont Anabaena azollae

Energy Technology Data Exchange (ETDEWEB)

Rozen, A.; Tel-Or, E.

1986-01-01

Sugar supported activities of H/sub 2/ production and C/sub 2/H/sub 2/ reduction were characterized in axenic cell cultures of the cyanobiont Anabaena azollae isolated from the water fern Azolla filiculoides. Fructose was found to be the favoured substrate, enhancing activities in both the light and the dark even at relatively low concentrations of 0.5-1.0 mM. Higher concentrations of sucrose, (10-20mM) also supported H/sub 2/ production and C/sub 2/H/sub 2/ reduction, while glucose was less effective. Levels of H/sub 2/ production were always lower than those of C/sub 2/H/sub 2/ reduction. 13 references.

Oxygen uptake from aquatic macrophyte decomposition from Piraju Reservoir (Piraju, SP, Brazil

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I. Bianchini Jr.

Full Text Available The kinetics of oxygen consumption related to mineralisation of 18 taxa of aquatic macrophytes (Cyperus sp, Azolla caroliniana, Echinodorus macrophyllus, Eichhornia azurea, Eichhornia crassipes, Eleocharis sp1, Eleocharis sp2, Hetereanthera multiflora, Hydrocotyle raniculoides, Ludwigia sp, Myriophyllum aquaticum, Nymphaea elegans, Oxycaryum cubense, Ricciocarpus natans, Rynchospora corymbosa, Salvinia auriculata, Typha domingensis and Utricularia foliosa from the reservoir of Piraju Hydroelectric Power Plant (São Paulo state, Brazil were described. For each species, two incubations were prepared with ca. 300.0 mg of plant (DW and 1.0 L of reservoir water sample. The incubations were maintained in the dark and at 20 ºC. Periodically the dissolved oxygen (DO concentrations were measured; the accumulated DO values were fitted to 1st order kinetic model and the results showed that: i high oxygen consumption was observed for Ludwigia sp (533 mg g-1 DW, while the lowest was registered for Eleocharis sp1 (205 mg g-1 DW mineralisation; ii the higher deoxygenation rate constants were verified in the mineralisation of A. caroliniana (0.052 day-1, H. raniculoides (0.050 day-1 and U. foliosa (0.049 day-1. The oxygen consumption rate constants of Ludwigia sp and Eleocharis sp2 mineralisation (0.027 day-1 were the lowest. The half-time of oxygen consumption varied from 9 to 26 days. In the short term, the detritus of E. macrophyllus, H. raniculoides, Ludwigia sp, N. elegans and U. foliosa were the critical resources to the reservoir oxygen demand; while in the long term, A. caroliniana, H. multiflora and T. domingensis were the resources that can potentially contribute to the benthic oxygen demand of this reservoir.

Growth and solar energy conversion of Azolla sp., cultivated under four solar irradiance flux density; Crescimento e conversao da energia solar de Azolla sp. cultivada em quatro densidades do fluxo radiante

Energy Technology Data Exchange (ETDEWEB)

Carvalho, E.F. de [Acre Univ., Rio Branco, AC (Brazil); Lopes, N.F. [Vicosa Univ., MG (Brazil). Dept. de Biologia Vegetal

1994-02-01

Growth and solar energy conversion were studied in three Azolla species grown under four levels (30, 50, 70 and 100%) of solar radiation incidence under outdoor conditions. Under full sunlight, the specie A. microphylla showed higher crop growth rate, relative growth rate, net assimilation rate and efficiency of solar energy conversion than the other ones. (author). 8 figs., 23 refs.

Reinterpretation of Azolla primaeva (Azollaceae, Eocene, Canada) using electron microscopy and X-ray tomographic microscopy

NARCIS (Netherlands)

Collinson, Margaret E.; van Konijnenburg-van Cittert, Johanna H.A.; Marone, Federica; Brain, Anthony P.R.

Azolla primaeva (Penhallow) Arnold fertile whole plants from the lower Eocene of Driftwood Creek, Canada have been examined using LM, SEM, TEM and SRXTM methods on hand specimens and sieved residues. The new data have resulted in an emended diagnosis. The megaspore is partly covered by filosum and

Crowdfunding the Azolla fern genome project: a grassroots approach.

Science.gov (United States)

Li, Fay-Wei; Pryer, Kathleen M

2014-01-01

Much of science progresses within the tight boundaries of what is often seen as a "black box". Though familiar to funding agencies, researchers and the academic journals they publish in, it is an entity that outsiders rarely get to peek into. Crowdfunding is a novel means that allows the public to participate in, as well as to support and witness advancements in science. Here we describe our recent crowdfunding efforts to sequence the Azolla genome, a little fern with massive green potential. Crowdfunding is a worthy platform not only for obtaining seed money for exploratory research, but also for engaging directly with the general public as a rewarding form of outreach.

Distribution of Azolla filiculoides Lam. (Azollaceae in Poland

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Ewa Szczęśniak

2011-01-01

Full Text Available Azolla filiculoides has been an ephemeral plant in Poland since the end of the 20th century. In the last 15 years this species appeared in 5 locations in south-west Poland. Habitat and plants of two populations became destroyed, three other still exist. A. filiculoides occurs in eutrophic or even polluted water where it forms dense mats, up to 10 cm thick. It stays sterile and propagates only in a vegetative manner. Frost resistance of Lower Silesia populations is higher than reported so far; fern may winter and rebuild the population after frost reaching 22oC. Size of the populations is changeable during the vegetation season. A. filiculoides occurs in water habitats and plant communities in which it substitutes Lemna minor.

Azolla-Anabaena's behaviour in urban wastewater and artificial media--influence of combined nitrogen.

Science.gov (United States)

Costa, M L; Santos, M C R; Carrapiço, F; Pereira, A L

2009-08-01

The results of using the nitrogen fixing symbiotic system Azolla-Anabaena to improve the quality of treated urban wastewater, particularly on what concerns phosphorus removal efficiencies (40-65%), obtained in continuous assays performed during the past few years and presented earlier, were very promising. Nevertheless, the presence of combined nitrogen in some wastewaters can compromise the treatment efficiency. The main goal of this work was to compare plants behaviour in wastewater and in mineral media with and without added nitrogen. Azolla filiculoides's specific growth rates in wastewater and in mineral media without added nitrogen or with low nitrate concentration were very similar (0.122 d(-1)-0.126 d(-1)), but decreased in the presence of ammonium (0.100 d(-1)). The orthophosphate removal rate coefficients were similar in all the growth media (0.210 d(-1)-0.232 d(-1)), but ammonium removal rate coefficient in wastewater was higher (0.117 d(-1)) than in mineral medium using that source of nitrogen (0.077 d(-1)). The ammonium present in wastewater, despite its high concentration (34 mg NL(-1)), didn't seem to inhibit growth and nitrogen fixation, however, in mineral media, ammonium (40 mg NL(-1)) was found to induce, respectively, 18% and 46% of inhibition.

Phytoremediation of domestic wastewaters in free water surface constructed wetlands using Azolla pinnata.

Science.gov (United States)

Akinbile, Christopher O; Ogunrinde, Temitope A; Che Bt Man, Hasfalina; Aziz, Hamidi Abdul

2016-01-01

Two constructed wetlands, one with Azolla pinnata plant (CW1) and the other without (CW2) for treating domestic wastewaters were developed. Fifteen water parameters which include: Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Total Phosphorus (TP), Total Nitrogen (TN), Ammoniacal Nitrogen (NH3N), Turbidity, pH, Electrical Conductivity (EC), Iron (Fe), Magnesium (Mg), Manganese (Mn), and heavy metals such as Lead (Pb) and Zinc (Zn) were analyzed using standard laboratory procedures. The experiments were conducted in two (dry and wet) seasons simultaneously. Results showed considerable reductions in all parameters and metals including Zn in CW1 compared with CW2 in the two seasons considered while Pb and Mn were not detected throughout the study. Zn concentration levels reduced significantly in both seasons just as removal efficiencies of 70.03% and 64.51% were recorded for CW1 while 35.17% and 33.45% were recorded for CW2 in both seasons. There were no significant differences in the removal efficiencies of Fe in both seasons as 99.55%, 59.09%, 88.89%, and 53.56% were recorded in CW1 and CW2 respectively. Azolla pinnata has proved effective in domestic wastewater phytoremediation studies.

Microcosm investigation of growth and phytoremediation potential of Azolla japonica along nitrogen gradients.

Science.gov (United States)

Park, Hun; Song, Uhram

2017-10-03

Although Azolla species are among the most promising plants for use in phytoremediation, more studies on their growth and nitrogen (N) uptake along the N gradients of growing media are required. In this study, N concentration-dependent growth in growing media and phosphorus (P) and N accumulation by Azolla japonica were studied by estimating direct N uptake from media by molybdenum-iron proteins. The doubling time of A. japonica was less than a week, regardless of the N concentration (0, 5, and 25 mg N/L) present in the growth media, indicating that this plant is suitable for remediation. Plants showed a high uptake of P, probably via plant-bacteria symbiosis, indicating their potential for effective P remediation. A. japonica also showed more than 4% N content regardless of the treatment and accumulated more than 40 mg of N per microcosm in 3 weeks. iron and molybdenum levels in plants were strongly associated with N fixation, and N uptake from media was estimated to be more than 25 mg per microcosm in 3 weeks, indicating that A. japonica has N remediation potential. As A. japonica is a rapidly growing plant, capable of efficient P and N remediation, it has great potential for use in phytoremediation of nutrient-enriched waters such as agricultural or urban wastewater and eutrophicated aquatic ecosystems.

Point and interval estimation of pollinator importance: a study using pollination data of Silene caroliniana.

Science.gov (United States)

Reynolds, Richard J; Fenster, Charles B

2008-05-01

Pollinator importance, the product of visitation rate and pollinator effectiveness, is a descriptive parameter of the ecology and evolution of plant-pollinator interactions. Naturally, sources of its variation should be investigated, but the SE of pollinator importance has never been properly reported. Here, a Monte Carlo simulation study and a result from mathematical statistics on the variance of the product of two random variables are used to estimate the mean and confidence limits of pollinator importance for three visitor species of the wildflower, Silene caroliniana. Both methods provided similar estimates of mean pollinator importance and its interval if the sample size of the visitation and effectiveness datasets were comparatively large. These approaches allowed us to determine that bumblebee importance was significantly greater than clearwing hawkmoth, which was significantly greater than beefly. The methods could be used to statistically quantify temporal and spatial variation in pollinator importance of particular visitor species. The approaches may be extended for estimating the variance of more than two random variables. However, unless the distribution function of the resulting statistic is known, the simulation approach is preferable for calculating the parameter's confidence limits.

Cellular responses in the cyanobacterial symbiont during its vertical transfer between plant generations in the Azolla microphylla symbiosis.

Science.gov (United States)

Zheng, Weiwen; Bergman, Birgitta; Chen, Bin; Zheng, Siping; Guan, Xiong; Xiang, Guan; Rasmussen, Ulla

2009-01-01

The nitrogen-fixing symbiosis between cyanobacteria and the water fern Azolla microphylla is, in contrast to other cyanobacteria-plant symbioses, the only one of a perpetual nature. The cyanobacterium is vertically transmitted between the plant generations, via vegetative fragmentation of the host or sexually within megasporocarps. In the latter process, subsets of the cyanobacterial population living endophytically in the Azolla leaves function as inocula for the new plant generations. Using electron microscopy and immunogold-labeling, the fate of the cyanobacterium during colonization and development of the megasporocarp was revealed. On entering the indusium chamber of the megasporocarps as small-celled motile cyanobacterial filaments (hormogonia), these differentiated into large thick-walled akinetes (spores) in a synchronized manner. This process was accompanied by cytoplasmic reorganizations and the release of numerous membrane vesicles, most of which contained DNA, and the formation of a highly structured biofilm. Taken together the data revealed complex adaptations in the cyanobacterium during its transition between plant generations.

Characterization and expression of a metallothionein gene in the aquatic fern Azolla filiculoides under heavy metal stress.

Science.gov (United States)

Schor-Fumbarov, Tamar; Goldsbrough, Peter B; Adam, Zach; Tel-Or, Elisha

2005-12-01

A cDNA encoding a type 2 metallothionein (MT) was isolated from Azolla filiculoides, termed AzMT2, accession no. AF482470. The AzMT2 transcript was expressed in sterile A. filiculoides that were free of the cyanobiont Anabaena azollae after erythromycin treatment, proving that AzMT2 is encoded by the fern genome. AzMT2 RNA expression was enhanced by the addition of Cd(+2), Cu(+2), Zn(+2) and Ni(+2) to the growth medium. The transcript level of AzMT2 correlated with the metal content in the plants. Temporal analysis of AzMT2 expression demonstrated that Cd(2+) and Ni(2+) induction of AzMT2 RNA expression occurred within 48 h. AzMT2-enhanced expression responded more intensely to the toxic Cd and Ni ions in A. filiculoides suggesting that AzMT2 may participate in detoxification mechanism. The more moderate response of AzMT2 to Zn and Cu ions, which are essential micronutrients, suggest a role for AzMT2 in metal homeostasis.

Reconstruction of the Arctic Ocean environment during the Eocene Azolla interval using geochemical proxies and climate modeling. Geologica Ultraiectina (331)

NARCIS (Netherlands)

Speelman, E.N.

2010-01-01

With the realization that the Arctic Ocean was covered with enormous quantities of the aquatic floating fern Azolla 49 Myrs ago, new questions regarding the Eocene conditions facilitating these blooms arose. This dissertation describes the reconstruction of paleo-environmental conditions

Azolla planting reduces methane emission and nitrogen fertilizer application in double rice cropping system in southern China

DEFF Research Database (Denmark)

Xu, Heshui; Zhu, Bo; Liu, Jingna

2017-01-01

Rice paddies are a major source of methane. How to reduce the methane emission in the paddy field without decreasing the yield has become a major concern of scientists, environmental groups, and agricultural policymakers worldwide. Azolla, used as a dual crop in rice cultivation, has multiple agr...

Performance of dead Azolla filiculoides biomass in Biosorption of Au from wastewater.

Science.gov (United States)

Umali, L J; Duncan, J R; Burgess, J E

2006-01-01

Dried milled biomass of Azolla filiculoides removed up to 98.2% of gold from wastewater from a gold plating factory containing 5 mg gold/l in solution in batch biosorption. The gold uptake capacity of the biomass was 98 mg/g. Whole dried biomass used in a continuous flow column removed up to 100% of gold from diluted wastewater. A similar column was linked to a sulphide precipitation process to provide a two-step system which was able to remove 98% of gold from undiluted wastewater containing 41 mg Au/l. The lifetime of the column was five days.

Bio indices for 2,4-D sensitivity between two plant species: Azolla pinnata R.Br. and Vernonia cinerea L. with their cellular responses.

Science.gov (United States)

De, Arnab Kumar; Dey, Narottam; Adak, Malay Kumar

2016-07-01

In the present experiment a pteridophytic species Azolla and an angiospermic species Vernonia were evaluated on the basis of cellular reactivity for herbicidal action through ongoing concentrations. Initially, both the species recorded a significant activity of IAA-oxidase as mark of IAA metabolism with herbicidal sensitivity. Still, Vernonia species were more affected on 2,4-D mediated auxin catabolism. The loss of auxin concentrations on the tissues by 2,4-D reaction was also reflected on growth parameters including relative growth rate and chlorophyll biosynthesis. In a dose dependent manner Vernonia plants were more affected with loss of chlorophyll content and decline in relative growth rate. On the other hand, both those parameters were adjusted significantly with 2,4-D accumulation in Azolla . The stability of cellular metabolism was documented by significant down regulation of protein and lipid peroxidation with concomitant moderation to superoxide and hydrogen peroxide accumulation. The later two were more vulnerable to damage in the Vernonia plant with profuse accumulation of protein and lipid peroxidation products. Similarly, tissue specific reaction to superoxide and hydrogen peroxide accumulation were distinctly demarcated in two species significantly. As a whole, the cellular responses and metabolite distribution to 2,4-D sensitization are the features to describe bio-indices for aquatic fern species Azolla with comparison to angiospermic species Vernonia .

Azolla-anabaena-bacteria system as a natural microcosm

Science.gov (United States)

Carrapico, Francisco J.

2002-02-01

Azolla is an aquatic fern that contains a permanent endosymbiotic prokaryotic community (cyanobacteria and bacteria) inside of the cavity in the leaf dorsal lobe of the pteridophyte. This is a unique situation and can be seen as a microcosm inside of an organism and also can be considered a good example of a living model for biological and environmental studies. These symbionts are specific of this symbiosis and lives immobilized in a mucilaginous fibrillar network, which fills part of the cavity. The symbionts works as immobilized organisms in a natural system that can be used as a model for biotechnological research and in biologically based life support systems. The nature and the complexity of this system is simultaneously a reference and a challenge for the research in the communication between the two levels of nature organization (microcosm and mesocosm), and can also be used as a reference for the design of new environmental engineered symbiotic systems that include man as a prelude to life in space.

Water ferns Azolla spp. (Azollaceae as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758 (Lepidoptera, Crambidae, Acentropinae

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Atousa Farahpour-Haghani

2017-01-01

Full Text Available Water ferns (Azolla spp., Azollaceae are reported for the first time as host plants for the larvae of the small China-mark moth Cataclysta lemnata (Linnaeus (Lepidoptera: Crambidae: Acentropinae in rice fields and waterways of northern Iran. Cataclysta lemnata is a semi-aquatic species that has been recorded to feed on Lemnaceae and a few other aquatic plants. However, it has not been reported before on Azolla spp. Larvae use water fern as food source and shelter and, at high population density in the laboratory, they completely wiped water fern from the water surface. Feeding was confirmed after rearing more than eight continual generations of C. lemnata on water fern in the laboratory. Adults obtained this way are darker and have darker fuscous markings in both sexes compared with specimens previously reported and the pattern remains unchanged after several generations.

Effects of the naturally-occurring contaminant microcystins on the Azolla filiculoides-Anabaena azollae symbiosis.

Science.gov (United States)

Pereira, A L; Monteiro, B; Azevedo, J; Campos, A; Osório, H; Vasconcelos, V

2015-08-01

Harmful algal blooms (HABs) contaminate aquatic ecosystems and are responsible for animal poisoning worldwide. We conducted a toxicity test with the aquatic fern and the biofertilizer, Azolla filiculoides. The sporophytes were exposed to three concentrations (0.01, 0.1 and 1μgmL(-1)) of a microcystin (MC) cyanobacterial crude extract and purified MC-LR. The growth of A. filiculoides decreased only at 1μgmL(-1) crude extract concentration while with MC-LR it decreased at all the tested concentrations, indicating that the presence of other compounds in the crude extract altered toxicity and stimulated the fern growth at lower concentrations (0.01 and 0.1μgmL(-1)). Both phycoerythrocyanin and allophycocyanin levels decreased in all the concentrations of crude extract and MC-LR. The phycocyanin had a marked increase at 0.1μgmL(-1) crude extract concentration and a marked decrease at 1μgmL(-1) MC-LR concentration. These changes in the phycobiliprotein content indicate a shift in the antenna pigments of the cyanobionts of A. filiculoides. The changes in two oxidative stress enzymes, glutathione reductase for the crude extract assay and glutathione peroxidase for MC-LR assay, points towards the induction of stress defense responses. The low bioconcentration factor in both crude extract and MC-LR treatments can suggest the low uptake of microcystins, and indicates that the aquatic fern can be used as a biofertilizer and as animal feed but is not suitable for MC phytoremediation. Copyright © 2015 Elsevier Inc. All rights reserved.

Hepatoprotective and antioxidant effects of Azolla microphylla based gold nanoparticles against acetaminophen induced toxicity in a fresh water common carp fish (Cyprinus carpio L.

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Selvaraj Kunjiappan

2015-04-01

Conclusion: Azolla microphylla phytochemically synthesized GNaP protects liver against oxidative damage and tissue damaging enzyme activities and could be used as an effective protector against acetaminophen-induced hepatic damage in fresh water common carp fish.

Salinity-induced inhibition of growth in the aquatic pteridophyte Azolla microphylla primarily involves inhibition of photosynthetic components and signaling molecules as revealed by proteome analysis.

Science.gov (United States)

Thagela, Preeti; Yadav, Ravindra Kumar; Mishra, Vagish; Dahuja, Anil; Ahmad, Altaf; Singh, Pawan Kumar; Tiwari, Budhi Sagar; Abraham, Gerard

2017-01-01

Salinity stress causes adverse physiological and biochemical changes in the growth and productivity of a plant. Azolla, a symbiotic pteridophyte and potent candidate for biofertilizer due to its nitrogen fixation ability, shows reduced growth and nitrogen fixation during saline stress. To better understand regulatory components involved in salinity-induced physiological changes, in the present study, Azolla microphylla plants were exposed to NaCl (6.74 and 8.61 ds/m) and growth, photochemical reactions of photosynthesis, ion accumulation, and changes in cellular proteome were studied. Maximum dry weight was accumulated in control and untreated plant while a substantial decrease in dry weight was observed in the plants exposed to salinity. Exposure of the organism to different concentrations of salt in hydroponic conditions resulted in differential level of Na + and K + ion accumulation. Comparative analysis of salinity-induced proteome changes in A. microphylla revealed 58 salt responsive proteins which were differentially expressed during the salt exposure. Moreover, 42 % spots among differentially expressed proteins were involved in different signaling events. The identified proteins are involved in photosynthesis, energy metabolism, amino acid biosynthesis, protein synthesis, and defense. Downregulation of these key metabolic proteins appears to inhibit the growth of A. microphylla in response to salinity. Altogether, the study revealed that in Azolla, increased salinity primarily affected signaling and photosynthesis that in turn leads to reduced biomass.

Photoproduction of hydrogen by a non-sulphur bacterium isolated from root zones of water fern Azolla pinnata

Energy Technology Data Exchange (ETDEWEB)

Singh, S.P.; Srivastava, S.C.; Pandey, K.D. (Banaras Hindu Univ., Varanasi (IN). Centre of Advanced Study in Botany)

1990-01-01

A photosynthetic bacterium Rhodopseudomonas sp. BHU strain 1 was isolated from the root zone of water fern Azolla pinnata. The bacterium was found to produce hydrogen with potato starch under phototrophic conditions. The immobilized bacterial cells showed sustained hydrogen production with a more than 4-fold difference over free cell suspensions. The data have been discussed in the light of possible utilization of relatively cheaper raw materials by non-sulphur bacteria to evolve hydrogen. (author).

Isotopic studies on nitrogen fixation and nitrogen cycling in blue-green algae and azolla. Final report for the period 1985-1989

Energy Technology Data Exchange (ETDEWEB)

Kauser, A M; Sikander, A [Nuclear Inst. for Agriculture and Biology, Faisalabad (Pakistan)

1990-12-31

Under the IAEA coordination project, a series of field and pot experiments have been conducted to demonstrate the various aspects of Azolla technology as a contribution of nitrogen to the nutrition of agricultural crops, especially rice. This final report summarizes the previous experiments and gives details on the last experiments. 1 fig., 7 tabs.

Isotopic studies on nitrogen fixation and nitrogen cycling in blue-green algae and azolla. Final report for the period 1985-1989

International Nuclear Information System (INIS)

Kauser, A.M.; Sikander, A.

1989-01-01

Under the IAEA coordination project, a series of field and pot experiments have been conducted to demonstrate the various aspects of Azolla technology as a contribution of nitrogen to the nutrition of agricultural crops, especially rice. This final report summarizes the previous experiments and gives details on the last experiments. 1 fig., 7 tabs

Potential of the aquatic fern Azolla filiculoides in biodegradation of an azo dye: modeling of experimental results by artificial neural networks.

Science.gov (United States)

Khataee, A R; Movafeghi, A; Vafaei, F; Lisar, S Y Salehi; Zarei, M

2013-01-01

The potential of an aquatic fern, Azolla filiculoides, in phytoremediation of a mono azo dye solution, C.I. Acid Blue 92 (AB92), was studied. The effects of operational parameters such as reaction time, initial dye concentration, fern fresh weight, pH, temperature and reusability of the fern on biodegradation efficiency were investigated. The intermediate compounds produced by biodegradation process were analyzed using GC-MS analysis. An artificial neural network (ANN) model was developed to predict the biodegradation efficiency. The findings indicated that ANN provides reasonable predictive performance (R2 = 0.961). The effects of AB92 solutions (10 and 20 mg L(-1)) on growth, chlorophylls and carotenoids content, activity of antioxidant enzymes such as superoxide dismutase, peroxidase and catalase and formation of malondialdehyde were analyzed. AB92 generally showed inhibitory effects on the growth. Moreover, photosynthetic pigments in the fronds significantly decreased in the treatments. An increase was detected for lipid peroxidation and antioxidant enzymes activity, suggesting that AB92 caused reactive oxygen species production in Azolla fronds, which were scavenged by induced activities of antioxidant enzymes.

Urea application promotes amino acid metabolism and membrane lipid peroxidation in Azolla.

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Chen, Jiana; Huang, Min; Cao, Fangbo; Pardha-Saradhi, P; Zou, Yingbin

2017-01-01

A pot experiment was conducted to evaluate the effect of urea on nitrogen metabolism and membrane lipid peroxidation in Azolla pinnata. Compared to controls, the application of urea to A. pinnata resulted in a 44% decrease in nitrogenase activity, no significant change in glutamine synthetase activity, 660% higher glutamic-pyruvic transaminase, 39% increase in free amino acid levels, 22% increase in malondialdehyde levels, 21% increase in Na+/K+- levels, 16% increase in Ca2+/Mg2+-ATPase levels, and 11% decrease in superoxide dismutase activity. In terms of H2O2 detoxifying enzymes, peroxidase activity did not change and catalase activity increased by 64% in urea-treated A. pinnata. These findings suggest that urea application promotes amino acid metabolism and membrane lipid peroxidation in A. pinnata.

A study on the Phytoremediation Potential of Azolla pinnata under laboratory conditions

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Upekha Mandakini Lenaduwa Lokuge

2016-11-01

Full Text Available Heavy metal contamination in aquatic environments has become one of the major environmental problems all over the world. Phytoremediation is a plant based technology that utilizes special plants known as hyperaccumulators to purify heavy metal contaminated sites. Hyperaccumulators are capable of absorbing heavy metals in greater concentrations.  Azolla pinnata is an aquatic macrophyte that has been earmarked for its hyperaccumulation ability. This green technology is often more favoured over conventional methods due to its low cost, low environmental impacts and wider public acceptance.This study was conducted under laboratory conditions to assess the ability of A. pinnata for the removal of Cr, Ni, Cd and Pb through rhizofiltration, which is one of the phytoremediation strategies under laboratory conditions. Under three main experiments, the fern’s phytoremediation ability was investigated. In the first experiment, A. pinnata was exposed to prepared solutions of Cr, Ni and Pb of 2ppm, 4ppm, 6ppm, 8ppm and 10ppm and of Cd solutions of 0.5ppm, 1.0ppm, 1.5ppm, 2.0ppm, 2.5ppm and 3.0ppm respectively. Experiments were carried out separately for Cr, Ni, Cd and Pb concentrations for 7 days. The concentrations of heavy metals used in the experiments largely agreed with the environmentally measured values, although in certain experiments, the initial concentrations exceeded the environmental pollution levels.The presence of Cr, Ni, Cd and Pb caused a maximum inhibition of A.pinnata growth by 47%, 54%, 52% and 45% respectively while the highest removal percentages of Cr- 98%, Ni- 57%, Cd- 88% and Pb- 86% were recorded in 2ppm, 2ppm, 0.5ppm and 8ppm treatments respectively. The highest Bio Concentration Factor (BCF for Cr was 1376.67 when treated with 6ppm, 684.95 at 4ppm for Ni, 1120.06 at 0.5ppm for Cd and 1332.53 at 8ppm for Pb respectively. At the end of the experiments toxic symptoms were observed in plats exposed to Cd and Ni. The findings of

Cytokinin-induced promotion of root meristem size in the fern Azolla supports a shoot-like origin of euphyllophyte roots.

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de Vries, Jan; Fischer, Angela Melanie; Roettger, Mayo; Rommel, Sophie; Schluepmann, Henriette; Bräutigam, Andrea; Carlsbecker, Annelie; Gould, Sven Bernhard

2016-01-01

The phytohormones cytokinin and auxin orchestrate the root meristem development in angiosperms by determining embryonic bipolarity. Ferns, having the most basal euphyllophyte root, form neither bipolar embryos nor permanent embryonic primary roots but rather an adventitious root system. This raises the questions of how auxin and cytokinin govern fern root system architecture and whether this can tell us something about the origin of that root. Using Azolla filiculoides, we characterized the influence of IAA and zeatin on adventitious fern root meristems and vasculature by Nomarski microscopy. Simultaneously, RNAseq analyses, yielding 36,091 contigs, were used to uncover how the phytohormones affect root tip gene expression. We show that auxin restricts Azolla root meristem development, while cytokinin promotes it; it is the opposite effect of what is observed in Arabidopsis. Global gene expression profiling uncovered 145 genes significantly regulated by cytokinin or auxin, including cell wall modulators, cell division regulators and lateral root formation coordinators. Our data illuminate both evolution and development of fern roots. Promotion of meristem size through cytokinin supports the idea that root meristems of euphyllophytes evolved from shoot meristems. The foundation of these roots was laid in a postembryonically branching shoot system. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Urea application promotes amino acid metabolism and membrane lipid peroxidation in Azolla.

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Jiana Chen

Full Text Available A pot experiment was conducted to evaluate the effect of urea on nitrogen metabolism and membrane lipid peroxidation in Azolla pinnata. Compared to controls, the application of urea to A. pinnata resulted in a 44% decrease in nitrogenase activity, no significant change in glutamine synthetase activity, 660% higher glutamic-pyruvic transaminase, 39% increase in free amino acid levels, 22% increase in malondialdehyde levels, 21% increase in Na+/K+- levels, 16% increase in Ca2+/Mg2+-ATPase levels, and 11% decrease in superoxide dismutase activity. In terms of H2O2 detoxifying enzymes, peroxidase activity did not change and catalase activity increased by 64% in urea-treated A. pinnata. These findings suggest that urea application promotes amino acid metabolism and membrane lipid peroxidation in A. pinnata.

Interactive effects of herbicide and enhanced UV-B on growth, oxidative damage and the ascorbate-glutathione cycle in two Azolla species.

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Prasad, Sheo Mohan; Kumar, Sushil; Parihar, Parul; Singh, Rachana

2016-11-01

A field experiment was conducted to investigate the impact of alone and combined exposures of herbicide pretilachlor (5, 10 and 20μgml(-1)) and enhanced UV-B radiation (UV-B1; ambient +2.2kJm(-2) day(-1) and UV-B2; ambient +4.4kJm(-2) day(-1)) on growth, oxidative stress and the ascorbate-glutathione (AsA-GSH) cycle in two agronomically important Azolla spp. viz., Azolla microphylla and Azolla pinnata. Decreased relative growth rate (RGR) in both the species under tested stress could be linked to enhanced oxidative stress, thus higher H2O2 accumulation was observed, that in turn might have caused severe damage to lipids and proteins, thereby decreasing membrane stability. The effects were exacerbated when spp. were exposed to combined treatments of enhanced UV-B and pretilachlor. Detoxification of H2O2 is regulated by enzymes/metabolites of AsA-GSH cycle such as ascorbate peroxidase (APX) and glutathione reductase (GR) activity that were found to be stimulated. While, dehydroascorabte reductase (DHAR) activity, and the amount of metabolites: ascorbate (AsA), glutathione (GSH) and ratios of reduced/oxidized AsA (AsA/DHA) and GSH (GSH/GSSG), showed significant reduction with increasing doses of both the stressors, either applied alone or in combination. Glutathione-S-transferase (GST), an enzyme involved in scavenging of xenobiotics, was found to be stimulated under the tested stress. This study suggests that decline in DHAR activity and in AsA/DHA ratio might have led to enhanced H2O2 accumulation, thus decreased RGR was noticed under tested stress in both the species and the effect was more pronounced in A. pinnata. Owing to better performance of AsA-GSH cycle in A. microphylla, this study substantiates the view that A. microphylla is more tolerant than A. pinnata. Copyright © 2016 Elsevier Inc. All rights reserved.

Dietary effects of Azolla pinnata combined with exogenous digestive enzyme (Digestin™) on growth and nutrients utilization of freshwater prawn, Macrobrachium rosenbergii (de Man 1879)

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Goda, Ashraf; Saad, Amal; Hanafy, Mohamed; Sharawy, Zaki; El-Haroun, Ehab

2017-07-01

The present study was conducted to evaluate the effect of either individual or combined wheat bran (WB) replacement with Azolla pinnata supplemented with Digestin™ in the diet of freshwater prawn,Macrobrachium rosenbergii Postlarvae (PL) on growth performance, nutrient utilization, chemical body composition and survival (%). Experimental diets were a wheat bran-soybean based diet with no Azolla and Digestin TM (control, T1), and diets containing 17% Azolla supplemented with Digestin TM 0% (T2), 1% (T3), 2% (T4) and 3% (T5). Each experimental diet was allocated into three tanks (6m3/tank) fed for 12 wks. Each tank was subdivided into three equal pens by nets (2m3) and stoked with 84 PL/m2. The experimental diets were readily consumed by prawns PLs where both high growth and good feed efficiency were achieved for all diets. The results showed that the diets containing A. pinnata supplemented with Digestin™ at the level up to 3% have the higher growth and better nutrient utilization than the control diet. No differences were observed for moisture and protein content among the experimental diets. However, the highest protein content was observed on prawns fed on diets T1 and T5 respectively, while the lowest value was recorded for T 4 diet. The results also show that prawn PLs fed the diets contain A. pinnata and supplemented with Digestin TM recorded the highest values of body lipid content compared to the control diet. Feed efficiency and economic conversion rate (ECR) values show that economic performance and the cost-effectiveness of the A. pinnata supplemented with up to 3% Digestin TM recorded the highest net return, and therefore it is recommended for prawn, M. rosenbergii PL's. These results are clearly indicating that A. pinnata have a good potential for use in prawn diets at reasonable levels than other conventional diets.

Antimicrobial activity and identification of potential antimicrobial compounds from aquatic pteridophyte, Azolla microphylla Kaulf.

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Abraham, G; Yadav, R K; Kaushik, G K

2015-04-01

Azolla microphylla Kaulf. is an aquatic nitrogen fixing pteridophyte commonly found in aquatic habitats including paddy fields. Methanolic extract of the fronds of A. microphylla was subjected to partial purification by solvent partitioning with diethyl ether and ethyl acetate followed by hydrolysis, and further partitioning with ethyl acetate. The two fractions, thus obtained were tested for antibacterial activity. It was observed that the ethyl acetate fraction inhibited the growth of the pathogenic bacterium Xanthomonas oryzae. The GC-MS analysis of the ethyl acetate fraction showed several prominent peaks with retention time ranging from 8.83 to 45.54 min. A comparison of these peaks with the GC-MS libraries revealed that it could be eicosenes and heptadecanes with potential of antimicrobial activity.

Effect of Azolla Based - Organic Fertilizer, Rock Phosphate and Rice Hull Ash on Rice Yield and Chemical Properties of Alfisols

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Sudadi

2014-07-01

Full Text Available The application of chemical fertilizer for long time may adverse soil environment. Organic agriculture, for example combination use of azolla based-organic fertilizer, phosphate rock and rice hull ash, was one of ways that able to recover it. Research was conducted in Sukosari, Jumantono, Karanganyar while soi chemical properties analysis was analysed in Soil Chemistry and Fertility Laboratory, Fac. of Agriculture, Sebelas Maret University April to November 2013. Research design used was RAKL with 5 treatments, each repeated 5 times. The treatments applied were P0 (control, P1 ( azola inoculum dosage 250 g/m2 + phosphate rock + rice hull ash equal to 150 kg/ha KCl, P2 (azola inoculum dosage 500 g/m2 + phosphate rock equal to 150kg/ha, SP-36 + rice hull ash equal to 100 kg/ha KCl, P3 (manure dosage of 5 ton/ha,P4 (Urea 250 kg/ha + SP-36 150 kg/ha + KCl 100 kg/ha. Data analysed statistically by F test (Fisher test with level of confident 95% followed by DMRT (Duncan Multiple Range Test if any significant differences. The result showed that the treatment combination of azolla, phosphate rock and rice hull ash increase soil organic matter content, cation exchange capacity, available-P and exchangeable-K as well as rice yield ( (at harvest-dry grain weight and milled-dry grain weight.

Toxicity of Diclofenac in the Fern Azolla filiculoides and the Lichen Xanthoria parietina.

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Vannini, Andrea; Paoli, Luca; Vichi, Marco; Bačkor, Martin; Bačkorová, Miriam; Loppi, Stefano

2018-03-01

This study investigated the occurrence of toxicity, expressed as damage to the photosynthetic apparatus, in the aquatic fern Azolla filiculoides and the lichen Xanthoria parietina following treatments with diclofenac at different concentrations (0.1, 1, 10 and 100 mg/L) and different exposure times (24, 48, 72 and 240 h). Measurements of photosynthetic efficiency, chlorophyll content and chlorophyll degradation indicated dose- and time-dependent toxicity, since significant differences with control samples as well as among treatments, emerged mainly for the highest concentration (100 mg/L) and the longest time (240 h). In addition, also the mycobiont of the lichen X. parietina showed similar toxic effects, expressed as ergosterol content. The absence of relevant alterations at the lowest concentration (0.1 mg/L) suggested a very limited susceptibility of these species to environmentally relevant levels of this pharmaceutical.

Revision of species of Minerisporites, Azolla and associated plant microfossils from deposits of the Upper Palaeocene and Palaeocene/Eocene transition in the Netherlands, Belgium and the USA.

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Batten, D J.; Collinson, M E.

2001-05-01

Species of the megaspore genus Minerisporites Potonié, megaspore apparatuses of species of the water fern Azolla Lamarck, and some associated organic-walled microfossils recovered from deposits of the Upper Palaeocene and Palaeocene/Eocene transition in the southern part of the Netherlands and neighbouring Belgium are redescribed on the basis of an examination of specimens under scanning and transmission electron microscopes. Originally studied about 40 years ago by S.J. Dijkstra, the re-examination has enabled emended diagnoses to be produced for six taxa: Minerisporites glossoferus (Dijkstra) Tschudy, M. mirabilis (Miner) Potonié, M. mirabilissimus (Dijkstra) Potonié, Azolla schopfii Dijkstra, A. teschiana Florschütz, and A. velus (Dijkstra) Jain and Hall. In addition, a revised description is provided for massulae of Salvinia Séguier that were originally thought to be megaspores and, hence, named by Dijkstra as Triletes? exiguus. The gross morphology and construction of the exospore of the species of Minerisporites are similar, but nevertheless sufficiently distinct for them to be maintained as separate taxa. Monolete microspores are preserved in hollows in the reticulate surface of some of the specimens of M. mirabilissimus. This is consistent with the presumed isoetalean affinity of Minerisporites. An apparent stratigraphic morphocline from M. glossoferus to M. mirabilis, suggested previously, is confirmed following our reassessment of their characteristics. The species of Azolla are all multi-floated, but they differ from each other in several ways, in particular with respect to the ultrastructure of the megaspore wall. They are also distinct from all other species that have been considered in sufficient detail for satisfactory comparisons to be made. The massulae of A. teschiana are described for the first time. The floats in A. velus are attached to the proximal part of the megaspore only by suprafilosal hairs. There are no maniculae. It is argued that

Skin Colour, Abdominal Fat, and Carcass Fat of Male Alabio Duck (Anas plathyrhincos Borneo Fed Azolla Based Ration

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R Samudera

2008-09-01

Full Text Available This was conducted to know the effect of Azzola usage in their dietary toward skin color abdomen fat and carcass fat of male Alabio duck. The subject of this research was male Alabio duck attain the age 3 weeks as number 80 tails, with average first body weight 390,82 ± 0,63 g.  The dietary contain 16% protein and 3000 kcal energy.  Observation parameters including abdomen fat percentage, carcass fat, and skin color. Complete Random Design (RAL consist of 4 treatments and 5 repeating was applied.  Each treatment unit consisted of 4 tails of male Alabio duck.  Set as treatment was levels of Azzola pinnata flour usage as much as 0 (A0; 7.5 (A2; 15 (A3; and 22.5% (A4.  The effect of treatment towards abdomen fat (A0, A1, A2, and A3 / 1.50; 1.41; 1.23; 0.92 %, carcass fat (A0, A1, A2, and A3 / 7.99; 7.53; 5.74; 5.25 %, and skin color (A0, A1, A2, and A3 / 2.66; 3.62; 3.94; 4.20.  this research showed result of that treatment influence was significantly difference (P < 0.05.   Conclusion of this research, that azolla usage within dietary is able to decrease abdomen fat degree and carcass fat, reform skin color, thus, produce yellow color or un-pale. (Animal Production 10(3: 164-167 (2008   Key Words: Alabio duck, azolla, skin color, abdomen fat, carcass fat

Dual application of duckweed and azolla plants for wastewater treatment and renewable fuels and petrochemicals production.

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Muradov, Nazim; Taha, Mohamed; Miranda, Ana F; Kadali, Krishna; Gujar, Amit; Rochfort, Simone; Stevenson, Trevor; Ball, Andrew S; Mouradov, Aidyn

2014-02-28

Shortages in fresh water supplies today affects more than 1 billion people worldwide. Phytoremediation strategies, based on the abilities of aquatic plants to recycle nutrients offer an attractive solution for the bioremediation of water pollution and represents one of the most globally researched issues. The subsequent application of the biomass from the remediation for the production of fuels and petrochemicals offers an ecologically friendly and cost-effective solution for water pollution problems and production of value-added products. In this paper, the feasibility of the dual application of duckweed and azolla aquatic plants for wastewater treatment and production of renewable fuels and petrochemicals is explored. The differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by these aquatic macrophytes were used as the basis for optimization of the composition of wastewater effluents. Analysis of pyrolysis products showed that azolla and algae produce a similar range of bio-oils that contain a large spectrum of petrochemicals including straight-chain C10-C21 alkanes, which can be directly used as diesel fuel supplement, or a glycerin-free component of biodiesel. Pyrolysis of duckweed produces a different range of bio-oil components that can potentially be used for the production of "green" gasoline and diesel fuel using existing techniques, such as catalytic hydrodeoxygenation. Differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by different aquatic macrophytes can be used for optimization of composition of wastewater effluents. The generated data suggest that the composition of the petrochemicals can be modified in a targeted fashion, not only by using different species, but also by changing the source plants' metabolic profile, by exposing them to different abiotic or biotic stresses. This study presents an attractive, ecologically friendly and cost-effective solution for efficient bio

Dual application of duckweed and azolla plants for wastewater treatment and renewable fuels and petrochemicals production

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2014-01-01

Background Shortages in fresh water supplies today affects more than 1 billion people worldwide. Phytoremediation strategies, based on the abilities of aquatic plants to recycle nutrients offer an attractive solution for the bioremediation of water pollution and represents one of the most globally researched issues. The subsequent application of the biomass from the remediation for the production of fuels and petrochemicals offers an ecologically friendly and cost-effective solution for water pollution problems and production of value-added products. Results In this paper, the feasibility of the dual application of duckweed and azolla aquatic plants for wastewater treatment and production of renewable fuels and petrochemicals is explored. The differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by these aquatic macrophytes were used as the basis for optimization of the composition of wastewater effluents. Analysis of pyrolysis products showed that azolla and algae produce a similar range of bio-oils that contain a large spectrum of petrochemicals including straight-chain C10-C21 alkanes, which can be directly used as diesel fuel supplement, or a glycerin-free component of biodiesel. Pyrolysis of duckweed produces a different range of bio-oil components that can potentially be used for the production of “green” gasoline and diesel fuel using existing techniques, such as catalytic hydrodeoxygenation. Conclusions Differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by different aquatic macrophytes can be used for optimization of composition of wastewater effluents. The generated data suggest that the composition of the petrochemicals can be modified in a targeted fashion, not only by using different species, but also by changing the source plants’ metabolic profile, by exposing them to different abiotic or biotic stresses. This study presents an attractive, ecologically friendly and cost

Sea surface salinity of the Eocene Arctic Azolla event using innovative isotope modeling

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Speelman, E. N.; Sewall, J. O.; Noone, D.; Huber, M.; Sinninghe Damste, J. S.; Reichart, G. J.

2009-04-01

With the realization that the Eocene Arctic Ocean was covered with enormous quantities of the free floating freshwater fern Azolla, new questions regarding Eocene conditions facilitating these blooms arose. Our present research focuses on constraining the actual salinity of, and water sources for, the Eocene Arctic basin through the application of stable water isotope tracers. Precipitation pathways potentially strongly affect the final isotopic composition of water entering the Arctic Basin. Therefore we use the Community Atmosphere Model (CAM3), developed by NCAR, combined with a recently developed integrated isotope tracer code to reconstruct the isotopic composition of global Eocene precipitation and run-off patterns. We further addressed the sensitivity of the modeled hydrological cycle to changes in boundary conditions, such as pCO2, sea surface temperatures (SSTs) and sea ice formation. In this way it is possible to assess the effect of uncertainties in proxy estimates of these parameters. Overall, results of all runs with Eocene boundary conditions, including Eocene topography, bathymetry, vegetation patterns, TEX86 derived SSTs and pCO2 estimates, show the presence of an intensified hydrological cycle with precipitation exceeding evaporation in the Arctic region. Enriched, precipitation weighted, isotopic values of around -120‰ are reported for the Arctic region. Combining new results obtained from compound specific isotope analyses (δD) on terrestrially derived n-alkanes extracted from Eocene sediments, and model outcomes make it possible to verify climate reconstructions for the middle Eocene Arctic. Furthermore, recently, characteristic long-chain mid-chain ω20 hydroxy wax constituents of Azolla were found in ACEX sediments. δD values of these C32 - C36 diols provide insight into the isotopic composition of the Eocene Arctic surface water. As the isotopic signature of the runoff entering the Arctic is modelled, and the final isotopic composition of

Comparative assessment of Azolla pinnata and Vallisneria spiralis in Hg removal from G.B. Pant Sagar of Singrauli Industrial region, India.

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Rai, Prabhat Kumar; Tripathi, B D

2009-01-01

The aim of the present work was to monitor the Hg pollution in water and sediments of G.B. Pant Sagar located in Singrauli Industrial Region, India and to suggest the efficient aquatic plants for its phytoremediation. The study assessed the comparative potential of a free floating water fern Azolla pinnata and submerged aquatic macrophyte Vallisneria spiralis to purify waters polluted by Hg. Six days laboratory experiments have been conducted to mark the percentage removal of Hg at initial concentration of 0.1, 0.5, 1.0 and 3.0 mg L(-1). The percentage removal of Hg was higher for A. pinnata (80-94%) than V. spiralis (70-84%). Likewise, the Hg accumulated in dry mass was much higher for A. pinnata and a high correlation (R(2) = 0.91 for A. pinnata and 0.99 for V. spiralis) was obtained between applied Hg doses and accumulated amounts in biomass. A concentration dependent decrease in chlorophyll a, protein, RNA, DNA and nutrients (NO(3-) and PO(4)(3-)) uptake was detected in A. pinnata and V. spiralis due to Hg toxicity. The decrease was more prominent in Azolla than Vallisneria. The results recommended the use of A. pinnata and V. spiralis to ameliorate the industrial effluents (thermal power, chlor-alkali and coal mine effluent) contaminated with Hg.

Removal of copper(II) ions from aqueous solutions by Azolla rongpong: batch and continuous study.

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Nedumaran, B; Velan, M

2008-01-01

Batch and packed bed continuous biosorption studies were conducted to investigate the kinetics and isotherms of Cu(II) ions on the biomass of blue green alga Azolla rongpong. It is observed that the biosorption capacity of algae depends on initial pH and dosage. The biosorption capacity increases with increasing concentration and follows Freundlich isotherm model well with k and n values 0.06223 and 0.949 respectively. The optimum pH of 3.5 with an algae dosage of 1 g/L was observed. The results indicate that with the advantage of high metal biosorption capacity and recovery of Cu(II) ions, A. rongpong can be used as an efficient and economic biosorbent for the removal and recovery of toxic heavy metals from aqueous wastes even at higher concentration.

Bioaccumulation of selected heavy metals by the water fern, Azolla filiculoides Lam. in a wetland ecosystem affected by sewage, mine and industrial pollution

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Wet, L.P.D. de; Schoonbee, H.J.; Pretorius, J.; Bezuidenhout, L.M. (Rand Afrikaans University, Johannesburg (South Africa). Depts. of Zoology and Botany, Research Unit for Aquatic and Terrestrial Ecosystems)

1990-10-01

The bio-accumulation of the heavy metals, Fe, Cu, Ni, Pb, Zn, Mn and Cr by the water fern, Azolla filiculoides Lam. in a wetland ecosystem polluted by effluents from sewage works, mines and industries was investigated. Results showed that the different metals can be accumulated by the water fern at concentration levels not necessarily related to their actual concentrations in the aquatic environment, as measured in this case, in the bottom sediments. 45 refs., 1 fig., 3 tabs.

Protective effect of Azolla microphylla on biochemical, histopathological and molecular changes induced by isoproterenol in rats.

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Bhaskaran, Sreenath Kunnathupara; Kannappan, Poornima

2017-05-01

Azolla microphylla is an important fast-growing aquatic plant trusted for its agronomic, nutritious and therapeutic uses. The present work is undertaken to investigate the protective effect of the ethanolic extract of Azolla microphylla (EAM) against the Isoproterenol (ISO) induced cardiotoxicity in rats. Rats were pre-treated with EAM (250 and 500mg/kg b.w.) for 28 days along with ISO (85mg/kg; s.c.) on the 29th and 30th days. ISO-induced rats displayed significant diminution in cardiac antioxidant enzymes activities, increased lipid peroxidation and alteration in cardiac marker enzymes. The same group also displayed an increase in levels of serum lipid profiles and pro-inflammatory cytokines (IL-6 and IL-8) accompanied with a significant reduction in the anti-inflammatory cytokine levels (IL-10). Moreover, the histopathological investigations in the heart tissue of ISO-induced group exhibited myocardial necrosis and inflammation, which correlated with the increased immunoreactivity for Bax/iNOS, whereas an absence of reactivity for Bcl-2 proteins. However, in EAM pre-treated rats, the activities of antioxidant enzymes, cardiac marker enzymes, membrane-bound ATPases together with the levels of lipid profile, non-enzymatic antioxidants, pro and anti-inflammatory cytokines were maintained at normalcy that was further supported by improving histopathological changes and myocardial architecture. The IHC results of EAM pre-treated rats indicate up-regulated and down-regulated expressions of Bcl-2 and Bax/iNOS proteins, respectively. Thus, the present study reveals that A. microphylla alleviates myocardial damage in ISO-induced cardiac injury and demonstrates cardioprotective potential which could be attributed to its potent antioxidant and free radical scavenging activity. A possible mechanism for the protective effect is the elevated expression of endogenous antioxidant defense enzymes, anti-inflammatory cytokines, degraded lipid peroxidation products and improved

Response of microbial communities to pesticide residues in soil restored with Azolla imbricata.

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Lu, Xiao-Ming; Lu, Peng-Zhen

2018-01-01

Under conditions of Azolla imbricata restoration, the high-throughput sequencing technology was employed to determine change trends of microbial community structures in the soil that had undergone long-term application of pesticides. The relationship between the content of pesticide residues in the soil and the microbial community structure was analyzed. The results indicated that the microbial diversity was strongly negatively correlated with the contents of pesticide residues in the soil. At a suitable dosage of 5 kg fresh A. imbricata per square meter of soil area, the soil microbial diversity increased by 12.0%, and the contents of pesticide residues decreased by 26.8-72.1%. Sphingobacterium, Sphingopyxis, Thermincola, Sphingobium, Acaryochloris, Megasphaera, Ralstonia, Pseudobutyrivibrio, Desulfitobacterium, Nostoc, Oscillochloris, and Aciditerrimonas may play major roles in the degradation of pesticide residues. Thauera, Levilinea, Geothrix, Thiobacillus, Thioalkalispira, Desulfobulbus, Polycyclovorans, Fluviicola, Deferrisoma, Erysipelothrix, Desulfovibrio, Cytophaga, Vogesella, Zoogloea, Azovibrio, Halomonas, Paludibacter, Crocinitomix, Haliscomenobacter, Hirschia, Silanimonas, Alkalibacter, Woodsholea, Peredibacter, Leptolinea, Chitinivorax, Candidatus_Lumbricincola, Anaerovorax, Propionivibrio, Parasegetibacter, Byssovorax, Runella, Leptospira, and Nitrosomonas may be indicators to evaluate the contents of pesticide residues.

Induction of salt tolerance in Azolla microphylla Kaulf through modulation of antioxidant enzymes and ion transport.

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Abraham, Gerard; Dhar, Dolly Wattal

2010-09-01

Azolla microphylla plants exposed directly to NaCl (13 dsm(-1)) did not survive the salinity treatment beyond a period of one day, whereas plants exposed directly to 4 and 9 dsm(-1) NaCl were able to grow and produce biomass. However, plants pre-exposed to NaCl (2 dsm(-1)) for 7 days on subsequent exposure to 13 dsm(-1) NaCl were able to grow and produce biomass although at a slow rate and are hereinafter designated as pre-exposed plants. The pre-exposed and directly exposed plants distinctly differed in their response to salt in terms of lipid peroxidation, proline accumulation, activity of antioxidant enzymes, such as SOD, APX, and CAT, and Na(+)/K(+) ratio. Efficient modulation of antioxidant enzymes coupled with regulation of ion transport play an important role in the induction of salt tolerance. Results show that it is possible to induce salt adaptation in A. microphylla by pre-exposing them to low concentrations of NaCl.

Temporal variation in the biomass and nutrient status of Azolla filiculoides Lam. (Salviniaceae in a small shallow dystrophic lake Variação temporal de biomassa e estado nutricional de Azolla filiculoides Lam (Salviniaceae em um pequeno lago raso distrófico

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Claudio Rossano Trindade Trindade

2011-12-01

Full Text Available AIM: This study determined the temporal variation of the biomass and the concentrations of carbon, nitrogen and phosphorus in Azolla filiculoides Lam. in a small (0.5 ha shallow dystrophic lake located in the city of Rio Grande (Rio Grande do Sul State, Brazil. METHOD: Sampling was conducted monthly between November 2000 and October 2001. The macrophytes were collected randomly in three replicates with a circular collector 0.3 m in diameter and subsequently washed with tap water and oven-dried at 60 ºC for determination of the dry weight and the nutrient status (i.e., carbon, nitrogen and phosphorus. Primary productivity was estimated by the variation in biomass among successive samples. RESULTS: A. filiculoides was present in the lake throughout the year and occupied between 50 and 80% of the surface area. The biomass values ranged from 34.2 g DW.m-2, recorded in May (autumn, to 170.9 g DW.m-2 in January (summer. The highest rate of primary productivity was 3.3 g DW.m-2.d-1, observed in June. The concentrations of carbon, nitrogen and phosphorus in the plant ranged between 403 and 551 g.kg-1, 13.4 and 25.7 g.kg-1 and 0.5 and 1.9 g.kg-1, respectively. The water N:P ratio ranged between 19:1 and 368:1. CONCLUSION: The coverage of the surface of the lake by A. filiculoides throughout the study period and the nutritional status of the plant demonstrate the importance of the cycling of nutrients by macrophytes in this aquatic environment. The higher N:P ratio in the water column, compared with other neighboring environments without macrophytes, shows that the enrichment of the lake may result from the biological N-fixation activity produced by A. filiculoides.OBJETIVO: Este estudo determinou a variação temporal da biomassa e as concentrações de carbono, nitrogênio e fósforo de Azolla filiculoides Lam., em um pequeno lago raso distrófico situado no município do Rio Grande (Rio Grande do Sul, Brasil. MÉTODO: As amostragens foram realizadas

A green chemistry approach for the synthesis and characterization of bioactive gold nanoparticles using Azolla microphylla methanol extract

Science.gov (United States)

Kunjiappan, Selvaraj; Chowdhury, Ranjana; Bhattacharjee, Chiranjib

2014-06-01

This article reports the environmentally benign synthesis of gold nanoparticles (GNPs) using methanol extract of Azolla microphylla as the stabilizing and reducing agent. The GNPs were characterized by UV-vis spectrophotometry and FTIR, and the morphological characteristics were analyzed by XRD, FESEM-EDX and HRTEM. The GNPs could be formed in very short time, even in less than 30 min. The nanoparticles measured by UV-spectrophotometer demonstrated a peak at 540 nm corresponding to surface plasmon resonance spectra, and the peaks showed by FTIR suggested the presence of organic biomolecules on the surface of the GNPs. XRD results confirmed the crystalline nature of the GNPs, and FESEM-EDX and HRTEM analyses had been performed in the size ranges of 17-40 nm and 1.25-17.5 nm respectively. The synthesized GNPs showed excellent antioxidant activity. This study shows the feasibility of using plant sources for the biosynthesis of GNPs.

Cadmium-induced changes in pigments, total phenolics, and phenylalanine ammonia-lyase activity in fronds of Azolla imbricata.

Science.gov (United States)

Dai, Ling-Peng; Xiong, Zhi-Ting; Huang, Yu; Li, Min-Jing

2006-10-01

This study was designed to examine the effects of cadmium on several color-related parameters (including chlorophyll, carotenoid, and anthocyanin), total phenolics, and phenylalanine ammonia-lyase (PAL) activity in an aquatic fern species Azolla imbricate (A. imbricata). Cd accumulation and effects in the fronds were closely related with Cd concentration in the growth medium. The fronds under 0.5 mg/L Cd treatment turned red on the 3rd day, and this color change also appeared under 0.05 and 0.1 mg/L Cd treatment on the 5th day. Correlated with the color change, the contents of chlorophyll and carotenoid in the fronds significantly decreased in the presence of high Cd concentrations, while the anthocyanin content increased during the experiment. Significant increase in total phenolics content and PAL activity were also detected during Cd treatment. The results suggested that the Cd-induced change in color of fronds might be due to the decrease in chlorophyll and carotenoid and the increase in anthocyanin. Anthocyanin, total phenolics and their biosynthesis-related PAL might play a role in detoxification of Cd in A. imbricata.

Effect of aquatic plants on 95Zr concentration in slightly polluted water

International Nuclear Information System (INIS)

Shi Jianjun; Yang Ziyin; Chen Hui

2004-01-01

Effect of three aquatic plants (Ceratophyllum demersum, Azolla caroliniana and Eichhornia crassipes) on 95 Zr concentration in slightly polluted water was studied by using isotope tracer techniques. The results showed that the aquatic plants had strong ability of 95 Zr concentration in water. The concentration factor (CF) were from 56.78 to 112.94, so three aquatic plants were suggested be bio-indicators for 95 Zr polluted water. The specific activity of 95 Zr in water decreased with time when the aquatic plants were put in slightly 95 Zr polluted water. The descent of specific activity of 95 Zr in water was very quick during the beginning period (0-3d). The time for the specific activity reduced to 50% was only 3 days, indicating that theres aquatic plants could be used to purge slightly 95 Zr polluted water. The effect of Eichhornia crassipes on purging 95 Zr in water was the best among the three aquatic plants. The specific activity of 95 Zr in bottom clay only decreased 5% after putting aquatic plants in water, indicating that desorption of 95 Zr from bottom clay was not easy. As the bottom clay had strong ability of adsorption and fixation to 95 Zr, the effect of aquatic plant on purging 95 Zr adsorbed by bottom clay was not visible

Dicty_cDB: Contig-U12529-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available 0.81 9 ( EJ308578 ) 1095390124987 Global-Ocean-Sampling_GS-27-01-01-1... 34 0.84 3 ( EF520892 ) Azolla... microphylla voucher T. Lumpkin s.n. (DUKE)... 48 0.96 1 ( EF520891 ) Azolla microphyll...a voucher Watanabe s.n. (DUKE) t... 48 0.96 1 ( EF520887 ) Azolla mexicana voucher Zimmerman s.n. (DUKE) tRN...... 48 0.96 1 ( EF520885 ) Azolla mexicana voucher D.W. Rains s.n. (DUKE) tR... 48 0.96 1 ( DQ066515 ) Azo...lla microphylla voucher Reid & Peters 80 tRNA-... 48 0.96 1 ( DQ066511 ) Azolla mic

Field based investigation on phytoremediation potentials of Lemna minor and Azolla filiculoides in tropical, semiarid regions: Case of Ethiopia.

Science.gov (United States)

Amare, Elfu; Kebede, Fassil; Berihu, Tesfay; Mulat, Worku

2017-10-16

This study investigated the concurrent accumulation of eight heavy metals by two floating aquatic macrophytes (Lemna minor and Azolla filiculoides) cultivated in ambient media and blended wastewaters in the semiarid regions of Ethiopia. Both species accumulated heavy metals in varying degrees with a significant concentration gradient within the immediate water media. Highest bioconcentration factor was determined for Mn and Fe in both plants. Results revealed that L. minor was high phytoaccumulator for Fe, Mn, Zn and Co but moderate for Cd, Cu, Ni and Cr. On the other hand, A. filiculoides was a high accumulator for Fe, Mn, Zn and Cu, but its potency was moderate for Co, Cr and Ni, but lower for Cd. Both species exhibited significant difference in accumulating Co, Zn and Mn (p < 0.05). In general, the bioconcentration factors for both plants were comparable within the same treatment. In this study, stronger associations between the heavy metal concentrations in the plant tissues and in the grown water media were observed for A. filiculoides.

Proteomic analysis of the cyanobacterium of the Azolla symbiosis: identity, adaptation, and NifH modification.

Science.gov (United States)

Ekman, Martin; Tollbäck, Petter; Bergman, Birgitta

2008-01-01

Cyanobacteria are able to form stable nitrogen-fixing symbioses with diverse eukaryotes. To extend our understanding of adaptations imposed by plant hosts, two-dimensional gel electrophoresis and mass spectrometry (MS) were used for comparative protein expression profiling of a cyanobacterium (cyanobiont) dwelling in leaf cavities of the water-fern Azolla filiculoides. Homology-based protein identification using peptide mass fingerprinting [matrix-assisted laser desorption ionization-time of flight (MALDI-TOF-MS)], tandem MS analyses, and sequence homology searches resulted in an identification success rate of 79% of proteins analysed in the unsequenced cyanobiont. Compared with a free-living strain, processes related to energy production, nitrogen and carbon metabolism, and stress-related functions were up-regulated in the cyanobiont while photosynthesis and metabolic turnover rates were down-regulated, stressing a slow heterotrophic mode of growth, as well as high heterocyst frequencies and nitrogen-fixing capacities. The first molecular data set on the nature of the NifH post-translational modification in cyanobacteria was also obtained: peptide mass spectra of the protein demonstrated the presence of a 300-400 Da protein modification localized to a specific 13 amino acid sequence, within the part of the protein that is ADP-ribosylated in other bacteria and close to the active site of nitrogenase. Furthermore, the distribution of the highest scoring database hits for the identified proteins points to the possibility of using proteomic data in taxonomy.

A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Wetland Functions of Forested Wetlands in the West Gulf Coastal Plain Region of Arkansas

Science.gov (United States)

2005-08-01

shrub species in reference standard sites, but may dominate in degraded systems Carya illinoensis Carya cordiformis Carpinus caroliniana Carya ovata...americana sedges Carex spp. ironwood Carpinus caroliniana water hickory Carya aquatica bitternut hickory Carya cordiformis pecan Carya illinoensis ...and water hickory ( Carya aquatica). Less flooded sites are often dominated by green ash, Nuttall oak (Q. nuttallii), or willow oak, and the driest

Restoration using Azolla imbricata increases nitrogen functional bacterial groups and genes in soil.

Science.gov (United States)

Lu, Xiao-Ming; Lu, Peng-Zhen; Yang, Ke

2017-05-01

Microbial groups are major factors that influence soil function. Currently, there is a lack of studies on microbial functional groups. Although soil microorganisms play an important role in the nitrogen cycle, systematic studies of the effects of environmental factors on microbial populations in relation to key metabolic processes in the nitrogen cycle are seldom reported. In this study, we conducted a systematic analysis of the changes in nitrogen functional groups in mandarin orange garden soil treated with Azolla imbricata. The structures of the major functional bacterial groups and the functional gene abundances involved in key processes of the soil nitrogen cycle were analyzed using high-throughput sequencing (HTS) and quantitative real-time PCR, respectively. The results indicated that returning A. imbricata had an important influence on the composition of soil nitrogen functional bacterial communities. Treatment with A. imbricata increased the diversity of the nitrogen functional bacteria. The abundances of nitrogen functional genes were significantly higher in the treated soil compared with the control soil. Both the diversity of the major nitrogen functional bacteria (nifH bacteria, nirK bacteria, and narG bacteria) and the abundances of nitrogen functional genes in the soil showed significant positive correlations with the soil pH, the organic carbon content, available nitrogen, available phosphorus, and NH 4 + -N and NO 3 - -N contents. Treatment with 12.5 kg fresh A. imbricata per mandarin orange tree was effective to improve the quality of the mandarin orange garden soil. This study analyzed the mechanism of the changes in functional bacterial groups and genes involved in key metabolic processes of the nitrogen cycle in soil treated by A. imbricata.

Separation of toxic rhodamine B from aqueous solution using an efficient low-cost material, Azolla pinnata, by adsorption method.

Science.gov (United States)

Kooh, Muhammad Raziq Rahimi; Lim, Linda B L; Lim, Lee Hoon; Dahri, Muhammad Khairud

2016-02-01

This study investigated the potential of untreated Azolla pinnata (AP) to remove toxic rhodamine B (RB) dye. The effects of adsorbent dosage, pH, ionic strength, contact time, and concentration were studied. Experiments involving the effects of pH and ionic strength indicated that hydrophobic-hydrophobic interactions might be the dominant force of attraction for the RB-AP adsorption system. The kinetics modelling of the kinetics experiment showed that pseudo-second-order best represented the adsorption process. The Weber-Morris intraparticle diffusion model showed that intraparticle diffusion is not the rate-limiting step, while the Boyd model suggested that film diffusion might be rate-limiting. The adsorption isotherm model, Langmuir, best represented the adsorption process, and the maximum adsorption capacity was predicted to be 72.2 and 199.7 mg g(-1) at 25 and 65 °C, respectively. Thermodynamics study indicates spontaneity, endothermic and physisorption-dominant adsorption process. The adsorbents were regenerated to satisfactory level with distilled water, HNO3 and NaOH. Pre-treatment of adsorbent with oxalic acid, citric acid, NaOH, HCl and phosphoric acid was investigated but the adsorption capacity was less than the untreated AP.

Soil Fertility Status on Organic Paddy Experiment

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Mujiyo

2015-07-01

Full Text Available The study aims to determine fertility status of the soil after organic paddy experiments using kinds and doses of organic fertilizers. Experiment was conducted at greenhouse laboratory in Faculty of Agriculture Sebelas Maret University Surakarta. Experimental design used completely randomized design with 9 kinds of treatment was replicated 3 times. Experiments were the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations that are based on fulfilling nutrient requirements of 120 kg N ha-1. Result shows that the use of cow manure, Azolla fertilizers and Azolla inoculum had no effect on changes of soil fertility status. Soil fertility status was not significantly correlated with cow manure (0,16ns, Azolla fertilizer (0,26ns and Azolla inoculum (0,16ns. Average of final soil fertility status included fertile category, which was similar as the initial soil fertility status. Average of final soil properties of treatment but nevertheless was relatively higher than in no treatment, indicating the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations had greater impact to soil properties. Cow manure despite increased available K2O and dry grain, but it did not significantly increase the soil fertility status from fertile to very fertile. This was presumably due to the relatively short experiment period, only one planting season had not given significant effect to soil properties. Implication of this study is the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations although did not increase the soil fertility status but could maintain soil fertility status as the initial conditions before planting.

Phytoremediation of petroleum hydrocarbons by using a freshwater fern species Azolla filiculoides Lam.

Science.gov (United States)

Kösesakal, Taylan; Ünal, Muammer; Kulen, Oktay; Memon, Abdülrezzak; Yüksel, Bayram

2016-01-01

In this study, the phytoremediation capacity of Azolla filiculoides Lam. for the water resources contaminated with petroleum hydrocarbons was investigated. The plants were grown in nitrogen-free Hoagland nutrient solution containing 0.005%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% crude oil under greenhouse conditions for 15 days. Although the growth rate of the plants were not negatively influenced by the presence of crude oil in the media for the concentration of 0.005% and 0.01% v/v, a gradual impeding effect of crude oil in the growth media has been observed at concentrations 0.05-0.1%. More than 0.1% crude oil in the growth medium ostensibly retarded the growth. For example, 0.2% oil in the media reduced growth approximately 50% relative to the control, and the presence of crude oil at concentrations 0.3% or more were lethal. The data about the percentage of plant growth, fresh weight increase and root growth clearly indicated that the tolerance level of A. filiculoides plants to crude oil ranges between 0.1% and 0.2%. In comparison to control samples, the biodegradation rate of total aliphatic and aromatic (phenathrene) hydrocarbons at 0.05-0.2% oil concentrations, was 94-73% and 81-77%, respectively. On the other hand, in case of further increases in oil concentration in media, i.e.; 0.3-0.5%, the biodegradation rate was still higher in the experimental samples, respectively 71-63% and 75-71%. The high biodegradation rates of petroleum hydrocarbons in the experimental samples suggested that A. filiculoides plants could be a promising candidate to be used for the phytoremediation of low crude oil contaminated precious freshwater resources.

Is there foul play in the leaf pocket? The metagenome of floating fern

NARCIS (Netherlands)

Dijkhuizen, L.W.; Brouwer, P.; Bolhuis, H.; Reichart, G.-J.; Koppers, N.; Huettel, B.; Bolger, A.M.; Li, F.-W.; Cheng, S.; Liu, X.; Wong, G.K.-S.; Pryer, K.; Weber, A.; Bräutigam, A.; Schluepmann, H.

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla

Botanical ecology and conservation of the laguna de la herrera (sabana de bogotá, colombia)

OpenAIRE

Wijninga, V. M.; Rangel, Orlando; Cleef, A. M.

2012-01-01

Se estudió la vegetación alrededor de la Laguna de La Herrera, una laguna andina a 2550 m. Se diferenciaron una comunidad de Phytolacca bogotensis (1): comunidades helofíticas dominadas por: Scirpus californicus y Typha angustifolia (2); Scirpus californicus (3); Polygonum punctatum (4); Rumex obtusifolius y Polygonum punctatum (5); Bidens laevis (6); Hydrocotyle ranunculoides (7); comunidades pleustofíticas con: Limnobium laevigatum; (8); Azolla filiculoides y Lemna cf. gibba (9) y Eichhorni...

Evaluation of Fresh Azolla pinnata as a Low-Cost Supplemental Feed for Thai Silver Barb Barbonymus gonionotus

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Mousumi Das

2018-03-01

Full Text Available Aquatic fern Azolla pinnata comprises significant high food value with a good proportion of protein, vitamins, and minerals. This study was carried out to examine the effect of fresh A. pinnata as a substitution of commercial fish feed (CFF for Thai silver barb Barbonymus gonionotus. Post fingerlings of B. gonionotus were reared in five treatments, labeled T1 to T5, by substituting 0%, 25%, 50%, 75%, and 100% protein of CFF with A. pinnata protein (dry matter basis respectively for 56 days. The specific growth rate, net production rate, protein efficiency ratio, proximate composition, and overall conditions of fish were not significantly varied between the fish reared completely with CFF and 25% substitution with A. pinnata. However, a significantly higher profit rate (431.49 USD ha−1 56 day−1 was calculated for fish reared in T2 than other treatments. In contrast, there was a significant reduction of growth and other parameters of the fish that were observed in the case where more than 25% CFF was substituted with A. pinnata. The poorest performance was observed in fish fed completely with A. pinnata, at T5. Based on the results, 25% of CFF of Thai silver barb could be substituted with fresh A. pinnata without significantly lowering their growth and product quality and could contribute significant to a higher profit margin.

Mitigating yield-scaled greenhouse gas emissions through combined application of soil amendments: A comparative study between temperate and subtropical rice paddy soils

International Nuclear Information System (INIS)

Ali, Muhammad Aslam; Kim, P.J.; Inubushi, K.

2015-01-01

Effects of different soil amendments were investigated on methane (CH 4 ) and nitrous oxide (N 2 O) emissions, global warming potential (GWP) and yield scaled GWPs in paddy soils of Republic of Korea, Japan and Bangladesh. The experimental treatments were NPK only, NPK + fly ash, NPK + silicate slag, NPK + phosphogypsum(PG), NPK + blast furnace slag (BFS), NPK + revolving furnace slag (RFS), NPK + silicate slag (50%) + RFS (50%), NPK + biochar, NPK + biochar + Azolla-cyanobacteria, NPK + silicate slag + Azolla-cyanobacteria, NPK + phosphogypsum (PG) + Azolla-cyanobacteria. The maximum decrease in cumulative seasonal CH 4 emissions was recorded 29.7% and 32.6% with Azolla-cyanobacteria plus phospho-gypsum amendments in paddy soils of Japan and Bangladesh respectively, followed by 22.4% and 26.8% reduction with silicate slag plus Azolla-cyanobacteria application. Biochar amendments in paddy soils of Japan and Bangladesh decreased seasonal cumulative N 2 O emissions by 31.8% and 20.0% respectively, followed by 26.3% and 25.0% reduction with biochar plus Azolla-cyanobacteria amendments. Although seasonal cumulative CH 4 emissions were significantly increased by 9.5–14.0% with biochar amendments, however, global warming potentials were decreased by 8.0–12.0% with cyanobacterial inoculation plus biochar amendments. The maximum decrease in GWP was calculated 22.0–30.0% with Azolla-cyanobacteria plus silicate slag amendments. The evolution of greenhouse gases per unit grain yield (yield scaled GWP) was highest in the NPK treatment, which was decreased by 43–50% from the silicate slag and phosphogypsum amendments along with Azolla-cyanobacteria inoculated rice planted soils. Conclusively, it is recommended to incorporate Azolla-cyanobacteria with inorganic and organic amendments for reducing GWP and yield scaled GWP from the rice planted paddy soils of temperate and subtropical countries. - Highlights: • Azolla-cyanobacteria with organic and inorganic amendments

Batch and column studies on biosorption of acid dyes on fresh water macro alga Azolla filiculoides.

Science.gov (United States)

Padmesh, T V N; Vijayaraghavan, K; Sekaran, G; Velan, M

2005-10-17

The biosorption of Acid red 88 (AR88), Acid green 3 (AG3) and Acid orange 7 (AO7) by deactivated fresh water macro alga Azolla filiculoides was investigated in batch mode. Langmuir and Freundlich adsorption models were used for the mathematical description of the batch biosorption equilibrium data and model constants were evaluated. The adsorption capacity was pH dependent with a maximum value of 109.0 mg/g at pH 7 for AR88, 133.5 mg/g at pH 3 for AG3 and 109.6 mg/g at pH 3 for AO7, respectively, was obtained. The pseudo first and second order kinetic models were also applied to the experimental kinetic data and high correlation coefficients favor pseudo second order model for the present systems. The ability of A. filiculoides to biosorb AG3 in packed column was also investigated. The column experiments were conducted to study the effect of important design parameters such as initial dye concentration (50-100 mg/L), bed height (15-25 cm) and flow rate (5-15 mL/min) to the well-adsorbed dye. At optimum bed height (25 cm), flow rate (5 mL/min) and initial dye concentration (100 mg/L), A. filiculoides exhibited 28.1mg/g for AG3. The Bed Depth Service Time model and the Thomas model were used to analyze the experimental data and the model parameters were evaluated.

Stress responses of duckweed (Lemna minor L.) and water velvet (Azolla filiculoides Lam.) to anionic surfactant sodium-dodecyl-sulphate (SDS).

Science.gov (United States)

Forni, C; Braglia, R; Harren, F J M; Cristescu, S M

2012-04-01

Surfactants are used for several purposes and recently they have attracted the attention for their ability to modify the behavior of other preexistent or co-disposed contaminants, although their use or discharge in wastewaters can represent a real or potential risk for the environment. Lemna minor L. and Azolla filiculoides Lam. are floating aquatic macrophytes, very effective in accumulating several pollutants including sodium dodecyl sulphate (SDS). In this work we evaluated the effects of SDS on these species by determining the stress ethylene production via laser-based trace gas detection, and the activities of enzymes involved in stress response, such as guaiacol peroxidase (G-POD), phenylalanine ammonia-lyase (PAL) and polyphenol-oxidase (PPO). Phenolics content was also determined. The macrophytes were treated with different concentrations of SDS for one week. SDS affected duckweed enzymatic activities and phenol content. While in the fern phenolics amount, PAL, G-POD and PPO activities were not affected by SDS except for 100 ppm SDS, the only concentration that was taken up and not completely degraded. Stress ethylene production was induced only in the fern treated with 50 and 100 ppm SDS. Copyright © 2011 Elsevier B.V. All rights reserved.

Mitigating yield-scaled greenhouse gas emissions through combined application of soil amendments: A comparative study between temperate and subtropical rice paddy soils

Energy Technology Data Exchange (ETDEWEB)

Ali, Muhammad Aslam, E-mail: litonaslam@yahoo.com [Dept. of Environmental Science, Bangladesh Agricultural University, Mymensingh 2202 (Bangladesh); Dept. of Agricultural Chemistry, Gyeongsang National University, Jinju (Korea, Republic of); Division of Environmental Horticulture, Chiba University, Matsudo, Chiba 271-8510 (Japan); Kim, P.J., E-mail: pjkim@nongae.gsnu.ac.kr [Dept. of Agricultural Chemistry, Gyeongsang National University, Jinju (Korea, Republic of); Inubushi, K. [Division of Environmental Horticulture, Chiba University, Matsudo, Chiba 271-8510 (Japan)

2015-10-01

Effects of different soil amendments were investigated on methane (CH{sub 4}) and nitrous oxide (N{sub 2}O) emissions, global warming potential (GWP) and yield scaled GWPs in paddy soils of Republic of Korea, Japan and Bangladesh. The experimental treatments were NPK only, NPK + fly ash, NPK + silicate slag, NPK + phosphogypsum(PG), NPK + blast furnace slag (BFS), NPK + revolving furnace slag (RFS), NPK + silicate slag (50%) + RFS (50%), NPK + biochar, NPK + biochar + Azolla-cyanobacteria, NPK + silicate slag + Azolla-cyanobacteria, NPK + phosphogypsum (PG) + Azolla-cyanobacteria. The maximum decrease in cumulative seasonal CH{sub 4} emissions was recorded 29.7% and 32.6% with Azolla-cyanobacteria plus phospho-gypsum amendments in paddy soils of Japan and Bangladesh respectively, followed by 22.4% and 26.8% reduction with silicate slag plus Azolla-cyanobacteria application. Biochar amendments in paddy soils of Japan and Bangladesh decreased seasonal cumulative N{sub 2}O emissions by 31.8% and 20.0% respectively, followed by 26.3% and 25.0% reduction with biochar plus Azolla-cyanobacteria amendments. Although seasonal cumulative CH{sub 4} emissions were significantly increased by 9.5–14.0% with biochar amendments, however, global warming potentials were decreased by 8.0–12.0% with cyanobacterial inoculation plus biochar amendments. The maximum decrease in GWP was calculated 22.0–30.0% with Azolla-cyanobacteria plus silicate slag amendments. The evolution of greenhouse gases per unit grain yield (yield scaled GWP) was highest in the NPK treatment, which was decreased by 43–50% from the silicate slag and phosphogypsum amendments along with Azolla-cyanobacteria inoculated rice planted soils. Conclusively, it is recommended to incorporate Azolla-cyanobacteria with inorganic and organic amendments for reducing GWP and yield scaled GWP from the rice planted paddy soils of temperate and subtropical countries. - Highlights: • Azolla-cyanobacteria with organic and

Competition Between Lemna minuta, Lemna minor, and Azolla filiculoides. Growing Fast or Being Steadfast?

Directory of Open Access Journals (Sweden)

Simona Paolacci

2018-06-01

Full Text Available A substantial number of Lemnaceae are invasive outside their natural distribution area. Lemna minuta is considered invasive in several European countries, where it can occur in the same habitat as invasive Azolla filiculoides and native Lemna minor. In this study the presence, abundance and growth rates of all three species were monitored across 24 natural ponds and in a series of mesocosms in order to explore the importance of species invasiveness and habitat invisibility. Field monitoring showed that the distribution of the three species of macrophytes is heterogeneous in space and time. However, the data show no association of nutrient or light levels with plant distribution. Indeed, using reciprocal transplanting experiments it was demonstrated that all species are able to grow in all ponds, even ponds where the species do not naturally occur. It is concluded that distribution of L. minor, L. minuta, and A. filiculoides is not limited by the prevailing physicochemical characteristics of the ponds during the summer period. Remarkably, in these experiments A. filiculoides displayed the highest RGR, and exerted a negative influence on growth rates and surface cover of L. minor and L. minuta. Despite such apparent invasiveness, A. filiculoides was relatively rare in the study area. Rather, the species most abundant was L. minor which has the lowest RGR under field conditions in summer. Therefore, this study shows that the invasiveness of the species during the summer months is not necessarily reflected in the actual distribution pattern in natural ponds. In fact, alien L. minuta and A. filiculoides are under-represented in the monitored area. It is concluded that the interaction of several factors, including growth under winter-conditions and/or dispersal after disturbances, is the major determinant of the abundance and heterogeneous distribution of L. minor, L. minuta, and A. filiculoides in the study area.

SOIL N, P AND K CONCENTRATIONS AND RICE YIELD INCREASED DUE TO THE APPLICATION OF Azolla pinnata

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A. Arivin Rivaie*

2014-01-01

Full Text Available Many studies showed that application of Azolla pinnata as biofertilizer improved soil fertility some agricultural crops, including rice, whereas farmers in Lampung consider that A. pinnata suppresses growth of rice seedlings, so they throw it field by raising irrigation water surface. Information on effects A. pinnata application on changes in nutrient availability and rice yield obtained from paddy fields of regions still rare. A study was carried out to investigate effects of different rates of A. pinnata on changes in N, P, K concentrations in paddy soils, N uptake, and rice yield. A well-irrigated paddy field was incorporated with A. pinnata, and then rice seedlings of Ciherang variety had been grown from June up to December 2009. Results: application of A. pinnata at dose of five t per ha increased concentration of N, P and K as well as rice yield. A. pinnata had a relatively high N content, ie 2.43 percent. Application of A. pinnata of 7.5 t per ha increased significantly available soil P, indicated that A. pinnata requires a fairly high P to grow optimally. Application of A. pinnata of 7.5 t per ha gave highest dry grain yield, suggests that application A. pinnata did not suppress rice yield, even use of A. pinnata as organic matter source will help to conserve fossil fuels and foreign exchange as well as will allow more paddy fields that can be fertilized by N.

Mitigating yield-scaled greenhouse gas emissions through combined application of soil amendments: A comparative study between temperate and subtropical rice paddy soils.

Science.gov (United States)

Ali, Muhammad Aslam; Kim, P J; Inubushi, K

2015-10-01

Effects of different soil amendments were investigated on methane (CH4) and nitrous oxide (N2O) emissions, global warming potential (GWP) and yield scaled GWPs in paddy soils of Republic of Korea, Japan and Bangladesh. The experimental treatments were NPK only, NPK+fly ash, NPK+silicate slag, NPK+phosphogypsum(PG), NPK+blast furnace slag (BFS), NPK+revolving furnace slag (RFS), NPK+silicate slag (50%)+RFS (50%), NPK+biochar, NPK+biochar+Azolla-cyanobacteria, NPK+silicate slag+Azolla-cyanobacteria, NPK+phosphogypsum (PG)+Azolla-cyanobacteria. The maximum decrease in cumulative seasonal CH4 emissions was recorded 29.7% and 32.6% with Azolla-cyanobacteria plus phospho-gypsum amendments in paddy soils of Japan and Bangladesh respectively, followed by 22.4% and 26.8% reduction with silicate slag plus Azolla-cyanobacteria application. Biochar amendments in paddy soils of Japan and Bangladesh decreased seasonal cumulative N2O emissions by 31.8% and 20.0% respectively, followed by 26.3% and 25.0% reduction with biochar plus Azolla-cyanobacteria amendments. Although seasonal cumulative CH4 emissions were significantly increased by 9.5-14.0% with biochar amendments, however, global warming potentials were decreased by 8.0-12.0% with cyanobacterial inoculation plus biochar amendments. The maximum decrease in GWP was calculated 22.0-30.0% with Azolla-cyanobacteria plus silicate slag amendments. The evolution of greenhouse gases per unit grain yield (yield scaled GWP) was highest in the NPK treatment, which was decreased by 43-50% from the silicate slag and phosphogypsum amendments along with Azolla-cyanobacteria inoculated rice planted soils. Conclusively, it is recommended to incorporate Azolla-cyanobacteria with inorganic and organic amendments for reducing GWP and yield scaled GWP from the rice planted paddy soils of temperate and subtropical countries. Copyright © 2015 Elsevier B.V. All rights reserved.

Biochemical and growth performance of the aquatic macrophyte Azolla filiculoides to sub-chronic exposure to cylindrospermopsin.

Science.gov (United States)

Santos, Catarina; Azevedo, Joana; Campos, Alexandre; Vasconcelos, Vitor; Pereira, Ana L

2015-11-01

Physiological and biochemical effects of cylindrospermopsin (CYN), a cyanobacterial toxin that inhibits protein synthesis and released during a harmful cyanobacterial bloom, has been overlooked in plants. Therefore, at the present research, the toxic effects (physiological and biochemical) of a crude extract containing CYN were assessed in the aquatic fern Azolla filiculoides exposed to three concentrations (0.05, 0.5 and 5 μg CYN mL(-1)). At 5 μg CYN mL(-1), fern growth rate has showed a drastic decrease (0.001 g g(-1) day(-1)) corresponding to a 99.8% inhibition, but at the concentrations of 0.05 and 0.5 μg CYN mL(-1) the growth rate was similar to the control plants. Growth rate also indicated a IC50 of 2.9 μg CYN mL(-1). Those data point to the presence of other compounds in the crude extract may stimulate the fern growth and/or the fern is tolerant to CYN. Chlorophyll (a and b), carotenoids and protein content as well as the activities of glutathione reductase (GR) and glutathione-S-transferase (GST) has increased at 5 μg CYN mL(-1) which may indicate that photosynthesis and protein synthesis are not affected by CYN and the probable activation of defense and detoxifying mechanisms to overcome the effects induced by the presence of CYN. Low uptake of cylindrospermopsin (1.314 μg CYN g(-1) FW) and low bioconcentration factor (0.401) point towards to a safe use of A. filiculoides as biofertilizer and as food source, but also indicate that the fern is not suitable for CYN phytoremediation.

Portable exhausters POR-004 SKID B, POR-005 SKID C, POR-006 SKID D storage plan

International Nuclear Information System (INIS)

Nelson, O.D.; Keller, G.M.

1997-01-01

This document provides a storage plan for portable exhausters POR-004 SKID B, POR-005 SKID C, AND POR-006 SKID D. The exhausters will be stored until they are needed by the TWRS (Tank Waste Remediation Systems) Saltwell Pumping Program. The storage plan provides criteria for portable exhauster storage, periodic inspections during storage, and retrieval from storage

Preliminary comparison of the uptake of chromium-51 and zinc-65 by three species of aquatic plants from Louisiana

International Nuclear Information System (INIS)

Sklar, F.H.

1980-01-01

Accumulation of radionuclides was much greater for duckweed (Spirodela punctata) than for larger aquatic plants of slower growth (Bacopa caroliniana and Elodea canadensis). Higher specific activity (dpm/gm) was recorded in leaves than in stems. Chromium-51 accumulation factors ranged from a low of 66 for stems of E. canadensis to a high of 436 for S. punctata fronds. Zinc-65 accumulation factors were much higher: 142 for stems of B. caroliniana and 18,118 for fronds of S. punctata. Significant reductions in zinc-65 activity in the water surrounding growing S. punctata was detected within 10 minutes

AcEST: DK944536 [AcEST

Lifescience Database Archive (English)

Full Text Available tion tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides...lignments: (bits) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...Amaranthus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculo

AcEST: DK951670 [AcEST

Lifescience Database Archive (English)

Full Text Available |Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides Align length ...ts) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla ... 47 ...entus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides GN=AzMT2

AcEST: DK946149 [AcEST

Lifescience Database Archive (English)

Full Text Available r|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides Align...nts: (bits) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...thus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides G

AcEST: DK957493 [AcEST

Lifescience Database Archive (English)

Full Text Available M2 Definition tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla fil...ificant alignments: (bits) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...onein OS=Amaranthus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

Pollinator specialization and pollination syndromes of three related North American Silene.

Science.gov (United States)

Reynolds, Richard J; Westbrook, M Jody; Rohde, Alexandra S; Cridland, Julie M; Fenster, Charles B; Dudash, Michele R

2009-08-01

Community and biogeographic surveys often conclude that plant-pollinator interactions are highly generalized. Thus, a central implication of the pollination syndrome concept, that floral trait evolution occurs primarily via specialized interactions of plants with their pollinators, has been questioned. However, broad surveys may not distinguish whether flower visitors are actual pollen vectors and hence lack power to assess the relationship between syndrome traits and the pollinators responsible for their evolution. Here we address whether the floral traits of three closely related hermaphroditic Silene spp. native to eastern North America (S. caroliniana, S. virginica, and S. stellata) correspond to predicted specialized pollination based on floral differences among the three species and the congruence of these floral features with recognized pollination syndromes. A nocturnal/diurnal pollinator exclusion experiment demonstrated that all three Silene spp. have diurnal pollinators, and only S. stellata has nocturnal pollinators. Multiyear studies of visitation rates demonstrated that large bees, hummingbirds, and nocturnal moths were the most frequent pollinators of S. caroliniana, S. virginica, and S. stellata, respectively. Estimates of pollen grains deposited and removed per visit generally corroborated the visitation rate results for all three species. However, the relatively infrequent diurnal hawkmoth pollinators of S. caroliniana were equally effective and more efficient than the most frequent large bee visitors. Pollinator importance (visitation X deposition) of each of the animal visitors to each species was estimated and demonstrated that in most years large bees and nocturnal moths were the most important pollinators of S. caroliniana and S. stellata, respectively. By quantifying comprehensive aspects of the pollination process we determined that S. virginica and S. stellata were specialized on hummingbirds and nocturnal moths, respectively, and S

AcEST: DK951482 [AcEST

Lifescience Database Archive (English)

Full Text Available S3M2 Definition tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla f...gnificant alignments: (bits) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...hionein OS=Amaranthus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

Changes in symbiotic and associative interrelations in a higher plant-bacterial system during space flight

Science.gov (United States)

Kordyum, V. A.; Man'ko, V. G.; Popova, A. F.; Shcherbak, O. H.; Mashinsky, A. L.; Nguen-Hgue-Thyok

The miniature cenosis consisting of the water fern Azolla with its associated symbiotic nitrogen-fixing cyanobacterium Anabaena and the concomitant bacteria was investigated. Ecological closure was shown to produce sharp quantitative and qualitative changes in the number and type of concomitant bacteria. Changes in the distribution of bacterial types grown on beef-extract broth after space flight were recorded. Anabaena azollae underwent the most significant changes under spaceflight conditions. Its cell number per Azolla biomass unit increased substantially. Thus closure of cenosis resulted in a weakening of control over microbial development by Azolla. This tendency was augmented by spaceflight factors. Reduction in control exerted by macro-organisms over development of associated micro-organisms must be taken into account in constructing closed ecological systems in the state of weightlessness.

Celulitis por citomegalovirus

Directory of Open Access Journals (Sweden)

A. Ruiz Lascano

2002-12-01

Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.

AcEST: DK953912 [AcEST

Lifescience Database Archive (English)

Full Text Available t_id Q8S3M2 Definition tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...cing significant alignments: (bits) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...etallothionein OS=Amaranthus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

AcEST: DK955431 [AcEST

Lifescience Database Archive (English)

Full Text Available t_id Q8S3M2 Definition tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...cing significant alignments: (bits) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...etallothionein OS=Amaranthus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

Phytoextraction potential of water fern (Azolla pinnata) in the removal of a hazardous dye, methyl violet 2B: Artificial neural network modelling.

Science.gov (United States)

Kooh, Muhammad Raziq Rahimi; Lim, Linda B L; Lim, Lee-Hoon; Malik, Owais Ahmed

2018-04-16

This study investigated the potential of Azolla pinnata (AP) in the removal of toxic methyl violet 2B (MV) dye wastewater using the phytoextraction approach with the inclusion of an Artificial Neural Network (ANN) modelling. Parameters examined included the effects of dye concentration, pH and plant dosage. The highest removal efficiency was 93% which was achieved at a plant dosage of 0.8 g (dye volume = 200 mL, initial pH = 6.0, initial dye concentration = 10 mg L -1 ). A significant decrease in relative frond number (RFN), a growth rate estimator, observed at a dye concentration of 20 mg L -1 MV indicated some toxicity, which coincided with the plant pigments studies where the chlorophyll a content was lower than the control. There were little differences in the plant pigment contents between the control and those in the presence of dye (5 to 15 mg L -1 ) indicating the tolerance of AP to MV at lower concentrations. A three-layer ANN model was optimized (6 neurons in the hidden layer) and successfully predicted the phytoextraction of MV (R = 0.9989, RMSE = 0.0098). In conclusion, AP proved to be a suitable plant that could be used for the phytoextraction of MV while the ANN modelling has shown to be a reliable method for the modelling of phytoextraction of MV using AP.

AcEST: DK961355 [AcEST

Lifescience Database Archive (English)

Full Text Available rEMBL tr_hit_id Q8S3M2 Definition tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoid...ences producing significant alignments: (bits) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...G67_AMACR Metallothionein OS=Amaranthus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

Metabolic adaptation, a specialized leaf organ structure and vascular responses to diurnal N

NARCIS (Netherlands)

Brouwer, Paul; Bräutigam, Andrea; Buijs, Valerie A.; Tazelaar, Anne O.E.; Werf, van der Adrie; Schlüter, Urte; Reichart, Gert Jan; Bolger, Anthony; Usadel, Björn; Weber, Andreas P.M.; Schluepmann, Henriette

2017-01-01

Sustainable agriculture demands reduced input of man-made nitrogen (N) fertilizer, yet N2 fixation limits the productivity of crops with heterotrophic diazotrophic bacterial symbionts. We investigated floating ferns from the genus Azolla that host phototrophic diazotrophic Nostoc azollae in leaf

Portable exhauster POR-007/Skid E and POR-008/Skid F storage plan

International Nuclear Information System (INIS)

Nelson, O.D.

1998-01-01

This document provides storage requirements for 1,000 CFM portable exhausters POR-O07/Skid E and POR-008/Skid F. These requirements are presented in three parts: preparation for storage, storage maintenance and testing, and retrieval from storage. The exhauster component identification numbers listed in this document contain the prefix POR-007 or POR-008 depending on which exhauster is being used

The omnipresent water fern

NARCIS (Netherlands)

Nierop, K.G.J.; Speelman, E.N.; de Leeuw, J.W.; Reichart, G.J.

2011-01-01

Several studies have reported the presence of large amounts of lignin in ubiquitously occurring species of the freshwater fern Azolla. Molecular analysis using flash pyrolysis and thermally assisted hydrolysis and methylation shows, however, that neither the leaves nor the roots of Azolla contain

DESAJUSTE EDUCATIVO POR REGIONES EN COLOMBIA: ¿COMPETENCIA POR SALARIOS O POR PUESTOS DE TRABAJO?

Directory of Open Access Journals (Sweden)

Maribel Castillo Caicedo

2007-06-01

Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación, entendida como un desajuste por exceso, entre el nivel educativo alcanzado por el individuo y el exigido por el puesto de trabajo en el cual se desempeña; esto se debe a que existe una demanda laboral estrecha de puestos de trabajo para personas calificadas en Colombia. Se analizan las contribuciones empíricas existentes y el debate sobre las mismas; se examinan las teorías que permiten explicar la existencia de un desajuste educativo y se realiza una revisión de la literatura internacional y nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis para desarrollar un esquema que permita determinar el comportamiento del individuo en el fenómeno de la sobreeducación.

AcEST: DK946119 [AcEST

Lifescience Database Archive (English)

Full Text Available TrEMBL tr_hit_id Q8S3M2 Definition tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...llothionein-like protein 2 OS=Azolla ... 47 6e-04 tr|Q1W3C8|Q1W3C8_CAMSI Metallothionin 2 OS=Camellia sinens...4G67_AMACR Metallothionein OS=Amaranthus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

In vitro antioxidant and hepatoprotective potential of Azolla microphylla phytochemically synthesized gold nanoparticles on acetaminophen - induced hepatocyte damage in Cyprinus carpio L.

Science.gov (United States)

Kunjiappan, Selvaraj; Bhattacharjee, Chiranjib; Chowdhury, Ranjana

2015-06-01

The present study aims to evaluate the hepatoprotective and antioxidant effects of gold nanoparticles (GNaP) biosynthesized through the mediation of Azolla microphylla and A. microphylla extract on acetaminophen-induced hepatocyte damage in common carp fish (Cyprinus carpio L.). The gold nanoparticles (100, 150, 200 μg/ml) and A. microphylla extract powder (100, 200, 400 μg/ml) were added to the primary hepatocytes in different conditions: treatment I (before 12 mM acetaminophen), treatment II (after 12 mM acetaminophen), and treatment III (both before and after 12 mM acetaminophen), and incubated. Among these, control group treated with 12 mM acetaminophen produced significantly elevated levels (50-80%) of lactate dehydrogenase (LDH), catalase (CAT), glutamate oxalate transaminase (GOT), glutamate pyruvate transaminase (GPT), and malondialdehyde (MDA), and significantly decreased the levels (60-75%) of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Treatment with methanol extract of A. microphylla phytochemically biosynthesized gold nanoparticles (100, 150, 200 μg/ml) and A. microphylla methanol extract powder (100, 200, 400 μg/ml) significantly improved the viability of cells in a culture medium. It also significantly reduced the levels of LDH, CAT, GOT, GPT, and MDA, and significantly increased the levels of SOD and GSH-Px. In conclusion, gold nanoparticles biosynthesized through A. microphylla demonstrated effective hepatoprotective and antioxidant effects than methanol extract of A. microphylla.

AcEST: DK943775 [AcEST

Lifescience Database Archive (English)

Full Text Available M2_AZOFI Metallothionein-like protein 2 OS=Azolla ... 54 3e-06 tr|O81528|O81528_MESCR Metallothionein OS=Mes...etallothionein-like protein 2 OS=Azolla filiculoides GN=AzMT2 PE=4 SV=1 Length = 77 Score = 54.3 bits (129),

Desajuste educativo por regiones en Colombia: ¿competencia por salarios o por puestos de trabajo?

Directory of Open Access Journals (Sweden)

Castillo Caicedo Maribel

2007-08-01

Full Text Available Este trabajo aporta una perspectiva del fenómeno de la sobreeducación,
entendida como un desajuste por exceso, entre el nivel educativo alcanzado
por el individuo y el exigido por el puesto de trabajo en el cual se
desempeña; esto se debe a que existe una demanda laboral estrecha de
puestos de trabajo para personas calificadas en Colombia. Se analizan las
contribuciones empíricas existentes y el debate sobre las mismas; se
examinan las teorías que permiten explicar la existencia de un desajuste
educativo y se realiza una revisión de la literatura internacional y
nacional sobre el tema. Adicionalmente, se plantean una serie de hipótesis
para desarrollar un esquema que permita determinar el comportamiento
del individuo en el fenómeno de la sobreeducación.

The simulation model of growth and cell divisions for the root apex with an apical cell in application to Azolla pinnata.

Science.gov (United States)

Piekarska-Stachowiak, Anna; Nakielski, Jerzy

2013-12-01

In contrast to seed plants, the roots of most ferns have a single apical cell which is the ultimate source of all cells in the root. The apical cell has a tetrahedral shape and divides asymmetrically. The root cap derives from the distal division face, while merophytes derived from three proximal division faces contribute to the root proper. The merophytes are produced sequentially forming three sectors along a helix around the root axis. During development, they divide and differentiate in a predictable pattern. Such growth causes cell pattern of the root apex to be remarkably regular and self-perpetuating. The nature of this regularity remains unknown. This paper shows the 2D simulation model for growth of the root apex with the apical cell in application to Azolla pinnata. The field of growth rates of the organ, prescribed by the model, is of a tensor type (symplastic growth) and cells divide taking principal growth directions into account. The simulations show how the cell pattern in a longitudinal section of the apex develops in time. The virtual root apex grows realistically and its cell pattern is similar to that observed in anatomical sections. The simulations indicate that the cell pattern regularity results from cell divisions which are oriented with respect to principal growth directions. Such divisions are essential for maintenance of peri-anticlinal arrangement of cell walls and coordinated growth of merophytes during the development. The highly specific division program that takes place in merophytes prior to differentiation seems to be regulated at the cellular level.

Structural Insights into the PorK and PorN Components of the Porphyromonas gingivalis Type IX Secretion System.

Directory of Open Access Journals (Sweden)

Dhana G Gorasia

2016-08-01

Full Text Available The type IX secretion system (T9SS has been recently discovered and is specific to Bacteroidetes species. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilizes the T9SS to transport many proteins including the gingipain virulence factors across the outer membrane and attach them to the cell surface via a sortase-like mechanism. At least 11 proteins have been identified as components of the T9SS including PorK, PorL, PorM, PorN and PorP, however the precise roles of most of these proteins have not been elucidated and the structural organization of these components is unknown. In this study, we purified PorK and PorN complexes from P. gingivalis and using electron microscopy we have shown that PorN and the PorK lipoprotein interact to form a 50 nm diameter ring-shaped structure containing approximately 32-36 subunits of each protein. The formation of these rings was dependent on both PorK and PorN, but was independent of PorL, PorM and PorP. PorL and PorM were found to form a separate stable complex. PorK and PorN were protected from proteinase K cleavage when present in undisrupted cells, but were rapidly degraded when the cells were lysed, which together with bioinformatic analyses suggests that these proteins are exposed in the periplasm and anchored to the outer membrane via the PorK lipid. Chemical cross-linking and mass spectrometry analyses confirmed the interaction between PorK and PorN and further revealed that they interact with the PG0189 outer membrane protein. Furthermore, we established that PorN was required for the stable expression of PorK, PorL and PorM. Collectively, these results suggest that the ring-shaped PorK/N complex may form part of the secretion channel of the T9SS. This is the first report showing the structural organization of any T9SS component.

Structural Insights into the PorK and PorN Components of the Porphyromonas gingivalis Type IX Secretion System.

Science.gov (United States)

Gorasia, Dhana G; Veith, Paul D; Hanssen, Eric G; Glew, Michelle D; Sato, Keiko; Yukitake, Hideharu; Nakayama, Koji; Reynolds, Eric C

2016-08-01

The type IX secretion system (T9SS) has been recently discovered and is specific to Bacteroidetes species. Porphyromonas gingivalis, a keystone pathogen for periodontitis, utilizes the T9SS to transport many proteins including the gingipain virulence factors across the outer membrane and attach them to the cell surface via a sortase-like mechanism. At least 11 proteins have been identified as components of the T9SS including PorK, PorL, PorM, PorN and PorP, however the precise roles of most of these proteins have not been elucidated and the structural organization of these components is unknown. In this study, we purified PorK and PorN complexes from P. gingivalis and using electron microscopy we have shown that PorN and the PorK lipoprotein interact to form a 50 nm diameter ring-shaped structure containing approximately 32-36 subunits of each protein. The formation of these rings was dependent on both PorK and PorN, but was independent of PorL, PorM and PorP. PorL and PorM were found to form a separate stable complex. PorK and PorN were protected from proteinase K cleavage when present in undisrupted cells, but were rapidly degraded when the cells were lysed, which together with bioinformatic analyses suggests that these proteins are exposed in the periplasm and anchored to the outer membrane via the PorK lipid. Chemical cross-linking and mass spectrometry analyses confirmed the interaction between PorK and PorN and further revealed that they interact with the PG0189 outer membrane protein. Furthermore, we established that PorN was required for the stable expression of PorK, PorL and PorM. Collectively, these results suggest that the ring-shaped PorK/N complex may form part of the secretion channel of the T9SS. This is the first report showing the structural organization of any T9SS component.

Effets de l'alimentation des poissons avec Azolla sur la production d'un écosystème agro-piscicole en zones marécageuses au Rwanda

Directory of Open Access Journals (Sweden)

Kanangire, CK.

2002-01-01

Full Text Available Effects of Azolla-based Meal on the Production of an Agro-piscicultural Ecosystem in Rwanda Marshlands. Cette étude analyse les différences de caractères au niveau de la descendance des croisements interspécifiques entre Sesamum indicum L. et Ceratotheca sesamoides Endl. Les résultats obtenus montrent que l'héritabilité de la présence d'une forte pilosité sur les tiges et sur les pétioles est contrôlée par deux gènes assortis et indépendants. Les deux gènes dominants S et P confèrent aux plantes une importante pilosité sur les tiges et sur les pétioles tandis qu'un allèle dominant S-pp et ss-P confère aux plantes une pilosité respectivement abondante sur les tiges st sur les pétioles. Seuls les génotypes homozygotes sspp avec deux gènes récessifs produisent des plantes avec peu de poils sur les tiges et sur les pétioles. Les implications de ces résultats dans l'évolution de ces espèces sont discutées.

The PorX response regulator of the Porphyromonas gingivalis PorXY two-component system does not directly regulate the Type IX secretion genes but binds the PorL subunit.

Directory of Open Access Journals (Sweden)

Maxence S Vincent

2016-08-01

Full Text Available The Type IX secretion system (T9SS is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion of surface attachment of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY and PorX encode typical two-component system (TCS sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of the porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we showed that PorX does not bind and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS.

The PorX Response Regulator of the Porphyromonas gingivalis PorXY Two-Component System Does Not Directly Regulate the Type IX Secretion Genes but Binds the PorL Subunit

Science.gov (United States)

Vincent, Maxence S.; Durand, Eric; Cascales, Eric

2016-01-01

The Type IX secretion system (T9SS) is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion or cell surface exposition of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY, and PorX encode typical two-component system (TCS) sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN, and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we demonstrate that PorX does not bind T9SS gene promoters and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS. PMID:27630829

AcEST: DK945877 [AcEST

Lifescience Database Archive (English)

Full Text Available ionein-like type 1 protein OS=Ip... 57 5e-07 tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides GN=AzMT2 PE=4 SV=1

AcEST: DK960984 [AcEST

Lifescience Database Archive (English)

Full Text Available Metallothionein-like protein 2 OS=Azolla ... 57 6e-07 tr|O81529|O81529_MESCR Metallothionein OS=Mesembryant...S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides GN=AzMT2 PE=4 SV=1 Length = 77 Score

Encefalopatía por priones

Directory of Open Access Journals (Sweden)

Carlos Colegial

1999-01-01

Full Text Available Las encefalopatías espongiformes por priones son enfermedades neurodegenerativas que pueden ser esporádicas o transmisibles, ya sea por mecanismos infecciosos o hereditarios. Su investigación ha planteado enormes retos y en el recorrido histórico en busca de su causa dos médicos han recibido el premio Nobel de Medicina: Carleton Gajdusek, por sus trabajos en Nueva Guinea donde describió la transmisión infecciosa por ritos canibalísticos, que llevó a estudios de transmisión experimental en chimpancés y a su teoría de los "virus lentos" (por el largo período de incubación de la enfermedad.

Effect of Two Kinds of Green Manure and Urea on Production and N Uptake by Lowland Rice

International Nuclear Information System (INIS)

Haryanto; Idawati; Havid Rasjid; Elsje L Sisworo

2004-01-01

One field experiment has been conducted to study effect of two kinds of green manure and urea on production and N uptake in lowland rice. This experiment were used 11 treatments : (U) applying urea fertilizer at dose 200 kg urea/ha or recommended dose, (1/2 U) urea at 100 kg/ha, (1/2 U + Az) urea at 100 kg/ha + Azolla inoculation, (1/2 U + S) urea at 100 kg/ha + Sesbania incorporated at 50 DAT (days after transplanting), (Az + S) Azolla inoculation + Sesbania incorporated at 50 DAT, (Az + Sph) Azolla inoculation + Sesbania crop imported into the soil as green manure applied at preparation time of the land, (1/2 U + Az + S) treatment of (Az + S) combined with 100 kg urea/ha application, (1/2 U + Az + Sph) treatment of (Az + Sph) combined with 100 kg urea/ha application, (A) inoculation of Azolla, (S) Sesbania incorporated at 50 DAT, and Control (without urea, Azolla, and Sesbania). Lowland rice variety Cilosari was used in this experiment. This experiment was designed by Randomized Complete Block Design with 4 replicates for each treatment. To study the N-derived from fertilizer and green manure the 15 N isotope technique was used with the non direct method. Labelled 15 N ammonium sulphate with 10.12% 15 N was applied at 1 m x 1 m isotope plots for each plot in this experiment. The result showed that treatment combination of 100 kg urea/ha + Azolla inoculation + Sesbania crop incorporated into the soil as green manure applied at preparation time of the land gave N availability of soil higher than that resulted by 200 kg Urea/ha application. These treatments were not significantly different for total N uptake and N-derived from fertilizer in the rice grain. (author)

AcEST: DK943861 [AcEST

Lifescience Database Archive (English)

Full Text Available AZOFI Metallothionein-like protein 2 OS=Azolla ... 57 6e-07 tr|O81529|O81529_MESCR Metallothionein OS=Mesemb...tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides GN=AzMT2 PE=4 SV=1 Length = 77

Effects of Permanently Raised Water Tables on Forest Overstory Vegetation in the Vicinity of the Tennessee-Tombigbee Waterway.

Science.gov (United States)

1982-08-01

Mississippi Valley* Common Name Scientific Name Very Tolerant** Water hickory Carya aquatica Pecan C. illinoensis Buttonbush Cephalanthus occidentalis...Table I (Concluded) Common Name Scientific Name Intolerant* Ironwood Carpinus caroliniana Bitternut hickory Carya cordiformis Shellbark

Natural Areas Inventory 1981 (GREAT III)

Science.gov (United States)

1982-01-01

lanuginosa 3 Campsis radicans Carpinus caroliniana Carya cordifonnis Carya illinoensis Carya laciniosa Carya ovalis 2. Carya ovata Carya ...texana Carya toraentosa Ceanothus americanus Celastrus scandens 2, Celtis laevigata ^Celtis occidentalis Celtis tenuifolia 3 Cephalanthus

Casipoemas por Navidad : (1969-2010)

OpenAIRE

Sena Medina, Guillermo

2011-01-01

PRESENTACIÓN AL AIRE DE LA POESÍA RELIGIOSA Y NAVIDEÑA DE GUILLERMO SENA MEDINA Constituye un gran honor hacer la presentación de Guillermo Sena Medina por un doble motivo; por la larga y sincera amistad que nos une desde hace muchos años al socaire de nuestra común afición por la Historia, como cronistas oficiales de nuestros municipios; y, sobre todo y particularmente, por su rica y profunda personalidad como hombre de letras, nacida de su aún más rica y profunda personalidad humana. A...

Evolution of NADPH-cytochrome P450 oxidoreductases (POR) in Apiales - POR 1 is missing

DEFF Research Database (Denmark)

Andersen, Trine Bundgaard; Hansen, Niels Bjørn; Laursen, Tomas

2016-01-01

The NADPH-dependent cytochrome P450 oxidoreductase (POR) is the obligate electron donor to eukaryotic microsomal cytochromes P450 enzymes. The number of PORs within plant species is limited to one to four isoforms, with the most common being two PORs per plant. These enzymes provide electrons to ...... (available from the SRA at NCBI). All three genes were shown to be functional upon reconstitution into nanodiscs, confirming that none of the isoforms are pseudogenes....

AcEST: DK960896 [AcEST

Lifescience Database Archive (English)

Full Text Available ke protein OS=Ipomoea b... 57 4e-07 tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla ... 57 6...SNC C DPC C Sbjct: 45 KATEGGHACKCGSNCPC-DPCNC 66 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

Osteomalacia inducida por tumor: hemangiopericitoma rinosinusal

Directory of Open Access Journals (Sweden)

Enriqueta M. Serafini

2013-02-01

Full Text Available La osteomalacia inducida por tumor es una rara enfermedad del metabolismo óseo caracterizada por el aumento en la excreción de fosfato a nivel renal seguido de hipofosfatemia. Es causada por agentes fosfatúricos producidos por determinados tumores. La resección total del tumor resulta en la completa reversión de las anormalidades bioquímicas, la desaparición de las manifestaciones clínicas y los hallazgos en los estudios por imágenes. Presentamos el caso de un varón de 61 años con cuadro clínico y laboratorio compatibles con osteomalacia oncogénica inducida por tumor mesenquimático de localización rinosinusal. En nuestro caso el diagnóstico histológico correspondió a una neoplasia de tipo vascular: hemangiopericitoma.

AcEST: DK958586 [AcEST

Lifescience Database Archive (English)

Full Text Available OS=Ipomoea b... 57 3e-07 tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla ... 57 6e-07 tr|O8...PC C Sbjct: 45 KATEGGHACKCGSNCPC-DPCNC 66 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla f

AcEST: DK962367 [AcEST

Lifescience Database Archive (English)

Full Text Available 8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla ... 57 2e-06 tr|O81529|O81529_MESCR Metallothion...DPCNC 66 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla filiculoides GN=AzMT2 PE=4 SV=1 Le

Porøse materialer

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place

2000-01-01

Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM).......Dette undervisningsnotat er en samling af noter, der refererer til den indledende del af kurset Materialmekanik og Porøse materailer på Insitut for Bærende Konstruktiner og Materialer (BKM)....

Controlled free radical attack in the apoplast: a hypothesis for roles of O, N and S species in regulatory and polysaccharide cleavage events during rapid abscission by Azolla.

Science.gov (United States)

Cohen, Michael F; Gurung, Sushma; Fukuto, Jon M; Yamasaki, Hideo

2014-03-01

Shedding of organs by abscission is a key terminal step in plant development and stress responses. Cell wall (CW) loosening at the abscission zone can occur through a combination chain breakage of apoplastic polysaccharides and tension release of cellulose microfibrils. Two distinctly regulated abscission cleavage events are amenable to study in small water ferns of the genus Azolla; one is a rapid abscission induced by environmental stimuli such as heat or chemicals, and the other is an ethylene-induced process occurring more slowly through the action of hydrolytic enzymes. Although free radicals are suggested to be involved in the induction of rapid root abscission, its mechanism is not fully understood. The apoplast contains peroxidases, metal-binding proteins and phenolic compounds that potentially generate free radicals from H2O2 to cleave polysaccharides in the CW and middle lamella. Effects of various thiol-reactive agents implicate the action of apoplastic peroxidases having accessible cysteine thiols in rapid abscission. The Ca(2+) dependency of rapid abscission may reflect the stabilization Ca(2+) confers to peroxidase structure and binding to pectin. To spur further investigation, we present a hypothetical model for small signaling molecules H2O2 and NO and their derivatives in regulating, via modification of putative protein thiols, free radical attack of apoplastic polysaccharides. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

AcEST: DK962530 [AcEST

Lifescience Database Archive (English)

Full Text Available 34 3.2 tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla ... 34 3.2 tr|B5U0R0|B5U0R0_ANABR Met...7 +DHD Sbjct: 192 TGHDHD 197 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

Verdad por definición

OpenAIRE

Garrido Garrido, Julián

1997-01-01

Not available.La verdad por definición es un tipo peculiar de verdad científica, distinguible de las verdades lógicas, matemáticas y empíricas. La definición, por su parte, designa diversos procedimientos de asignación de significado, cuyas diferencias exigen una adjetivación cuidadosa: definiciones ostensivas y operacionales, definiciones de diccionario y definiciones teóricas. Pero sólo las del último tipo son verdaderas por definición. En el presente artículo se precisa el concepto formal ...

Electrocardiografo por computadora

OpenAIRE

Tinoco Hernandez, Rosanna; Paredes Bejarano, Margarita; Romero Chaglia, Norman; Yapur Auad, Miguel Eduardo

2009-01-01

El presente trabajo trata sobrees el diseño y la implementación de un graficador de señales cardiacas por computadora, para lo cual diseñamos un circuito electrónico capaz de recibir la senal analógica proveniente de la actividad electrica del corazón , amplificarla, y luego convertirla en una señal digital para ser procesada por software y finalmente ser graficada, siendo posible así observar la señal cardiaca en el monitor de un computador como un tren de pulsos. Cabe destacar que par...

Celulitis por citomegalovirus Cytomegalovirus cellulitis

Directory of Open Access Journals (Sweden)

A. Ruiz Lascano

2002-12-01

Full Text Available Las lesiones cutáneas por citomegalovirus (CMV son infrecuentes y a menudo una manifestación tardía de una enfermedad sistémica, que generalmente anuncia un curso fatal. Comunicamos un caso de celulitis por CMV: una mujer de 70 años con trasplante renal efectuado 1 mes antes de la consulta, terapia inmunosupresora con ciclosporina A y metilprednisona. La paciente ingresó por fiebre, dolor e impotencia funcional en pierna derecha. Comprobamos la existencia de una placa de 8 por 4 cm eritematoedematosa. La tratamos con antibióticos sin mejoría, por lo que realizamos un estudio histopatológico de piel que mostró cambios citopáticos compatibles con infección por CMV. Los cultivos bacteriológicos y micológicos fueron negativos. La inmunohistoquímica específica para CMV y el estudio de reacción en cadena de la polimerasa (PCR de la biopsia de piel fueron positivas, al igual que la antigenemia. El tratamiento con ganciclovir produjo la mejoría del cuadro clínico. En la literatura revisada no hemos encontrado la celulitis como manifestación de enfermedad cutánea por CMV.Cutaneous lesions in CMV infection are rare, often a late manifestation of systemic infection, and usually herald a fatal course. A 70 year-old woman received a kidney transplantation one month before consulting and immunosuppressive therapy that included cyclosporine A and methylprednisone. She complained of fever, local pain in her right leg, and an erythematous and swelling plaque. She was treated with intravenous antibiotics without improvement. A skin biopsy was performed and the tissue obtained was sent for bacterial and fungal cultures as well as for histological examination. Cultures were negative. The biopsy showed CMV cytopathic changes. Immunoperoxidase staining was positive for CMV and polymerase chain reaction (PCR testing revealed CMV DNA. She was treated with ganciclovir with resolution of the lesion. CMV cellulitis is a rare cutaneous manifestation

Stylet bundle morphology and trophically related enzymes of the hemlock woolly adelgid (Hemiptera: Adelgidae)

Science.gov (United States)

Kelly L.F. Oten; Allen C. Cohen; Fred P. Hain

2014-01-01

The hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), is a pest of eastern and Carolina hemlocks (Tsuga canadensis (L.) Carriere and Tsuga caroliniana Engelmann, respectively) in the eastern United States and has already caused catastrophic changes to eastern forests. As one of the significant...

The application dosage of Azolla pinnata in fresh and powder form as organic fertilizer on soil chemical properties, growth and yield of rice plant

Science.gov (United States)

Setiawati, Mieke Rochimi; Damayani, Maya; Herdiyantoro, Diyan; Suryatmana, Pujawati; Anggraini, Derisfha; Khumairah, Fiqriah Hanum

2018-02-01

The yield of rice plants is strongly influenced by N fertilizer. Nitrogen in rice plants has roles in vegetative growth, tiller formation and increasing yield through rice protein formation. Nitrogen supplied from organic fertilizers is better than inorganic fertilizers that may have environmental problem effects. Organic fertilizers from Azolla pinnata water fern contain higher N than other organic fertilizers. Symbiosis between A. pinnata and the N-fixing cyanobacteria results in high content of nitrogen, 3 to 5%. A. pinnata can be added to the rice field as organic fertilizer in form of fresh biomass or composted. Composted form can be ground into powder which passes through 100 mesh sieve. Preparation of compost powder of A. pinnata is done to reduce the constraints of voluminous application of organic fertilizers and to improve the efficiency of its use. The objective of this research was to compare the effect of the use of fresh A. pinnata and compost powder of A. pinnata on some soil and plant chemical properties and rice yield. The treatments applied were fresh A. pinnata at the dose of 0, 10 and 20 ton ha-1 and A. pinnata compost powder at 12.5 and 25 kg ha-1. The results showed that incorporation of fresh A. pinnata at 20 tons ha-1 and its compost powder at 25 kg ha-1 increased the available P of soil, plant P content and tiller number, but did not affect the content of organic-C, total soil N, plant N content and rice yield. This study suggested the benefits of A. pinnata compost powder technology in organic fertilization of soil to increase the nutrient content of soil and rice plants.

Botanical ecology and conservation of the Laguna de la Herrera (Sabana de Bogotá, Colombia Botanical ecology and conservation of the Laguna de la Herrera (Sabana de Bogotá, Colombia

Directory of Open Access Journals (Sweden)

Wijninga V. M.

1989-09-01

Full Text Available The acuatic, helophytic and pleustophytic vegetation of the Laguna de La Herrera, on the southwestern border of the high plain of Bogotá at 2550 m was studied following the Zurich- Montpellier approach. The communities recognized were: terrestrial community of Phytolacca bogotensis; helophytic communities of scirpus californicus and Typha angustifolia ; scirpus californicus ; Polygonum punctatum ; Rumex obtusifolius with Polygonum punctatum; Bidens laevis ; Hydrocotyle ranunculoides. Pleustophytic communities of Limnobium laevigatum; Azolla filiculoides with Lemna cf. gibba and Eichornia crassipes. The structure, floristic composition and ecological aspects were also considered. Several recommendations about conservation of the Laguna are given. Se estudió la vegetación alrededor de la Laguna de La Herrera, una laguna andina a 2550 m. Se diferenciaron una comunidad de Phytolacca bogotensis (1: comunidades helofíticas dominadas por: Scirpus californicus y Typha angustifolia (2; Scirpus californicus (3; Polygonum punctatum (4; Rumex obtusifolius y Polygonum punctatum (5; Bidens laevis (6; Hydrocotyle ranunculoides (7; comunidades pleustofíticas con: Limnobium laevigatum; (8; Azolla filiculoides y Lemna cf. gibba (9 y Eichhornia crassipes (10. Se registraron la estructura, composición florística, los rasgos ecológicos y la distribución de las comunidades y se comparó con la conductividad eléctrica y la calidad del agua. Finalmente, se hacen recomendaciones para la conservación de la laguna y la vegetación acuática.

Tendencia de la mortalidad por cáncer en Chile según diferencias por nivel educacional, 2000-2010

Directory of Open Access Journals (Sweden)

Cristian A. Herrera Riquelme

2015-01-01

Full Text Available Objetivo. Caracterizar la tendencia de la mortalidad por cáncer en Chile según diferencias por nivel educacional en el período 2000-2010 en la población mayor de 20 años. Métodos. Cálculo de las tasas de mortalidad específica por cáncer ajustadas por edad para diferentes niveles educacionales (NE, para el período 2000-2010. Las tasas obtenidas se analizaron con un modelo de regresión de Poisson, calculando el índice de desigualdad relativa (IDR y el índice de desigualdad de la pendiente (IDP para cada año. Resultados. Se registraron 232 541 muertes por cáncer en el período 2000-2010. Los tipos de cáncer más frecuentes fueron de mama, estómago y vesícula biliar en mujeres; y estómago, próstata y pulmón en hombres. Las tasas de mortalidad por cáncer estandarizadas por edad fueron mayores en los NE más bajos, excepto para el de mama en mujer y el de pulmón en hombres. Las mayores diferencias se encontraron en el de vesícula biliar en mujeres y el de estómago en hombres, con mayores tasas de mortalidad específica de hasta 49 y 63 veces respectivamente, para NE bajo respecto al NE alto. Entre 2000 y 2010, las diferencias en mortalidad por NE se redujeron para todos los cánceres combinados en ambos géneros, mama en mujeres, y pulmón y estómago en hombres. Conclusiones. Durante el período estudiado, la mortalidad por cáncer en Chile estuvo fuertemente asociada al NE de la población. Esta información debe ser considerada al definir estrategias nacionales para reducir la mortalidad específica por cáncer en los grupos más desprotegidos.

Muerte materna por malaria grave por Plasmodium vivax

Directory of Open Access Journals (Sweden)

Nancy Arróspide

Full Text Available Se presenta el caso de una mujer de 19 años con 29 semanas de gestación, procedente de Llumpe (Ancash con antecedentes de viajes a las localidades de Chanchamayo (Junín y Rinconada (Ancash. Ingresó al Hospital de Chacas (Ancash por presentar mal estado general, deshidratación, dificultad respiratoria, ictericia, sensación de alza térmica y dolor abdominal, tuvo reporte de: hemoparásitos 60% en frotis sanguíneo. Fue transferida al Hospital Ramos Guardia (Huaraz donde presentó mayor dificultad respiratoria, coluria, hematuria, disminución del débito urinario y reporte de Plasmodium (+, luego fue transferida al Hospital Cayetano Heredia (Lima donde ingresó a la Unidad de Cuidados Intensivos (UCI, con evolución a falla multiorgánica, óbito fetal y muerte materna. Se confirmó infección por Plasmodium vivax. Destacamos la importancia de mejorar nuestras capacidades de diagnóstico y manejo para brindar un tratamiento adecuado y oportuno.

Desenvolvimento de um kit de irrigação por microtubos com moto-bomba propulsionada por energia solar

OpenAIRE

Luiz Ricardo Sobenko

2016-01-01

O bombeamento de água por meio da energia solar vem se mostrando uma alternativa para localidades onde outras fontes de energia não estão disponíveis ou são limitadas. Torna-se interessante aliar essa alternativa a um sistema de irrigação que opera com vazão e pressão relativamente baixas, como a irrigação localizada por microtubos, possibilitando assim a obtenção de alta eficiência. No presente trabalho teve-se por objetivo dimensionar e avaliar um kit de irrigação por microtubos, alimentado...

Tendencia de la mortalidad por cáncer en Chile según diferencias por nivel educacional, 2000-2010

OpenAIRE

Cristian A. Herrera Riquelme; Lucy Kuhn-Barrientos; Roberto Rosso Astorga; Jorge Jiménez de la Jara

2015-01-01

Objetivo. Caracterizar la tendencia de la mortalidad por cáncer en Chile según diferencias por nivel educacional en el período 2000-2010 en la población mayor de 20 años. Métodos. Cálculo de las tasas de mortalidad específica por cáncer ajustadas por edad para diferentes niveles educacionales (NE), para el período 2000-2010. Las tasas obtenidas se analizaron con un modelo de regresión de Poisson, calculando el índice de desigualdad relativa (IDR) y el índice de desigualdad de la pendiente (ID...

Polución por material particulado fino (PM 2,5) incrementa las hospitalizaciones por insuficiencia cardiaca

OpenAIRE

Castro, Pablo; Vera, Jeanette; Cifuentes, Luis; Wellenius, Gregory; Verdejo, Hugo; Sepúlveda, Luis; Vukasovic, José Luis; Llevaneras, Silvana

2010-01-01

Antecedentes: Estudios recientes han reportado una asociación entre la contaminación ambiental por material particulado (PM) y el riesgo de hospitalizaciones de pacientes con insuficiencia cardiaca (IC). La región metropolitana de nuestro país constituye un área geográfica en la cual la contaminación es especialmente relevante, asociándose a incrementos periódicos en la morbimortalidad por causa respiratoria. Sin embargo el efecto de la polución por PM en la morbilidad de pacientes con IC no ...

AcEST: DK952680 [AcEST

Lifescience Database Archive (English)

Full Text Available otein OS=Ipomoea b... 57 3e-07 tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...onein-like protein 2 OS=Azolla filiculoides GN=AzMT2 PE=4 SV=1 Length = 77 Score = 56.6 bits (135), Expect =...C C DPC C Sbjct: 45 KATEGGHACKCGSNCPC-DPCNC 66 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothi

Maintenance of eastern hemlock forests: Factors associated with hemlock vulnerability to hemlock woolly adelgid

Science.gov (United States)

Mary Ann Fajvan; Petra Bohall Wood

2010-01-01

Eastern hemlock (Tsuga canadensis [L.]) is the most shade-tolerant and long-lived tree species in eastern North America. The hemlock woolly adelgid (Adelges tsugae) (HWA), is a nonnative invasive insect that feeds on eastern hemlock and Carolina hemlock (Tsuga caroliniana Engelm.). HWA currently is established in...

Application of macrophytes as biosorbents for radioactive liquid waste treatment; Aplicacao de macrofitas como biossorventes no tratamento de rejeitos radioativos liquidos

Energy Technology Data Exchange (ETDEWEB)

Vieira, Ludmila Cabreira

2016-07-01

Radioactive waste as any other type of waste should be treated and disposed adequately. It is necessary to consider its physical, chemical and radiological characteristics for choosing the appropriate action for the treatment and final disposal. Many treatment techniques currently used are economically costly, often invalidating its use and favoring the study of other treatment techniques. One of these techniques is biosorption, which demonstrates high potential when applied to radioactive waste. This technology uses materials of biological origin for removing metals. Among potential biosorbents found, macrophyte aquatics are useful because they may remove uranium present in the liquid radioactive waste at low cost. This study aims to evaluate the biosorption capacity of macrophyte aquatics Pistia stratiotes, Limnobium laevigatum, Lemna sp and Azolla sp in the treatment of liquid radioactive waste. This study was divided into two stages, the first one is characterization and preparation of biosorption and the other is tests, carried out with uranium solutions and real samples. The biomass was tested in its raw form and biosorption assays were performed in polypropylene vials containing 10 ml of solution of uranium or 10ml of radioactive waste and 0.20g of biomass. The behavior of biomass was evaluated by sorption kinetics and isotherm models. The highest sorption capacities found was 162.1 mg / g for the macrophyte Lemna sp and 161.8 mg / g for the Azolla sp. The equilibrium times obtained were 1 hour for Lemna sp, and 30 minutes for Azolla sp. With the real waste, the macrophyte Azolla sp presented a sorption capacity of 2.6 mg / g. These results suggest that Azolla sp has a larger capacity of biosorption, therefore it is more suitable for more detailed studies of treatment of liquid radioactive waste. (author)

Application of macrophytes as biosorbents for radioactive liquid waste treatment

International Nuclear Information System (INIS)

Vieira, Ludmila Cabreira

2016-01-01

Radioactive waste as any other type of waste should be treated and disposed adequately. It is necessary to consider its physical, chemical and radiological characteristics for choosing the appropriate action for the treatment and final disposal. Many treatment techniques currently used are economically costly, often invalidating its use and favoring the study of other treatment techniques. One of these techniques is biosorption, which demonstrates high potential when applied to radioactive waste. This technology uses materials of biological origin for removing metals. Among potential biosorbents found, macrophyte aquatics are useful because they may remove uranium present in the liquid radioactive waste at low cost. This study aims to evaluate the biosorption capacity of macrophyte aquatics Pistia stratiotes, Limnobium laevigatum, Lemna sp and Azolla sp in the treatment of liquid radioactive waste. This study was divided into two stages, the first one is characterization and preparation of biosorption and the other is tests, carried out with uranium solutions and real samples. The biomass was tested in its raw form and biosorption assays were performed in polypropylene vials containing 10 ml of solution of uranium or 10ml of radioactive waste and 0.20g of biomass. The behavior of biomass was evaluated by sorption kinetics and isotherm models. The highest sorption capacities found was 162.1 mg / g for the macrophyte Lemna sp and 161.8 mg / g for the Azolla sp. The equilibrium times obtained were 1 hour for Lemna sp, and 30 minutes for Azolla sp. With the real waste, the macrophyte Azolla sp presented a sorption capacity of 2.6 mg / g. These results suggest that Azolla sp has a larger capacity of biosorption, therefore it is more suitable for more detailed studies of treatment of liquid radioactive waste. (author)

Síndrome de Munchausen por mandato

OpenAIRE

Esteban, Miguel A.; Pérez, Miriam R.; Bracco, Anahí

2006-01-01

El Síndrome de Munchausen por mandato, "un trastorno ficticio, por el cual la enfermedad del niño es inducida, promovida o provocada por la persona más próxima a él, generalmente su madre", es todavía mal conocido y su génesis imperfectamente comprendida. Esta comunicación está destinada a esclarecer al pediatra esta patología, con elevada morbilidad y secuelas, como así también de altísima mo...

DESGASTE POR ABRASIÓN DEL ACERO API 5L X65 REVESTIDO CON NIOBIO POR ASPERSIÓN TÉRMICA A PLASMA Y CON INCONEL 625 POR SOLDADURA

Directory of Open Access Journals (Sweden)

JOSE MATOS

2012-01-01

Full Text Available El objetivo de este trabajo fue evaluar y caracterizar el comportamiento mecánico en desgaste del acero API 5L X65, revestido con niobio en comparación al desempeño del revestimiento de la aleación de inconel 625 empleados en la industria de petróleo y gas. El revestimiento de niobio fue obtenido por el proceso de aspersión térmica a plasma de arco no transferido y el revestimiento inconel 625 por soldadura con electrodo revestido. La resistencia al desgaste por abrasión fue evaluada según la norma Petrobras N-2568, en un tribómetro CTER, la rugosidad y el volumen de material desgastado se determinó a través de perfilometría y la dureza de los revestimientos por microscopia Vickers. Los revestimientos obtenidos fueron caracterizados respecto a su morfología por microscopia electrónica de barrido (MEB y microscopía óptica (MO. La mayor dureza del revestimiento con niobio obtenido puede haber contribuido a reducir la tasa de desgaste en comparación con el revestimiento de inconel 625.

CARACTERÍSTICAS DA VIOLÊNCIA SEXUAL SOFRIDA POR CRIANÇAS ASSISTIDAS POR UM PROGRAMA DE APOIO

OpenAIRE

KELLY LINHARES VASCONCELOS; ADRIANA GOMES NOGUEIRA FERREIRA; ELIANY NAZARÉ OLIVEIRA; DANIELLE D\\u2019ÁVILA SIQUEIRA; PATRÍCIA NEYVA DA COSTA PINHEIRO

2010-01-01

En Brasil, las estadísticas de la violencia sexual contra niños están lejos de reflejar la verdadera realidad actual debido a la baja notificación de los casos. La finalidad de este estudio fue caracterizar el abuso sexual sufrido por niños asistidos por el Programa Sentinela y el perfil del agresor, en Sobral-Ceará, en el periodo que va del 2002 al 2006. La muestra no probabilística intencional fue compuesta por 50 víctimas de abuso sexual y de las mismas, el 66% es del sexo femenino, con pr...

Abdome agudo por obstrução por ileobiliar

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Márcia Cristina de Alencastro

Full Text Available OBJETIVO: descrever a experiência na abordagem dos doentes com abdome agudo por obstrução por IB, desde o diagnóstico até o tratamento definitivo. MÉTODOS: estudo retrospectivo incluindo todos os casos de IB tratados em um período de 23 anos. De acordo com a abordagem cirúrgica realizada, os pacientes foram divididos em dois grupos (1 enterolitotomia com colecistectomia no segundo momento; e (2 enterolitotomia, colecistectomia e abordagem da fístula. RESULTADOS: Doze pacientes foram incluídos, sendo 11 mulheres (91,6%, com média de idade de 72,2 anos. Todos os pacientes apresentavam doenças associadas, principalmente hipertensão arterial sistêmica (75%. Dois pacientes não apresentavam sintomas significativos de obstrução intestinal. O diagnóstico de IB foi realizado em seis pacientes (50% antes da laparotomia. O grupo 1 foi constituído de oito pacientes e o grupo 2 de quatro, e a morbidade foi, respectivamente, 33,3% e 8,3%. A mortalidade foi 16,6% (um paciente de cada grupo. CONCLUSÃO: O manejo do IB deve ser individualizado. O tratamento da obstrução mediante remoção do cálculo biliar por enterotomia proximal é a escolha inicial para o tratamento do IB. A colecistectomia e a correção da fístula bilioentérica podem ser realizadas juntamente com a remoção do cálculo, no entanto, em pacientes com comorbidades significativas, esses procedimentos devem ser realizados posteriormente.

Uso das diretrizes para tratamento da úlcera por pressão por enfermeiros de um hospital geral

Directory of Open Access Journals (Sweden)

Elaine Maria Leite Rangel

2009-03-01

Full Text Available Este estudo objetivou identificar a freqüência do uso das diretrizes para o tratamento da úlcera por pressão(UP por enfermeiros de um hospital geral no interior do estado de São Paulo. É transversal de caráterdescritivo com análise quantitativa de dados. Amostra de 25 enfermeiros. Para a coleta de dados utilizou-se uminstrumento, construído a partir das diretrizes para o tratamento da UP. As questões foram relacionadas aostipos de intervenções usadas pelos enfermeiros para o tratamento da UP em estágio I, II, com necrose e comtecido de granulação. Para UP em estágio I, 24 (96% enfermeiros sempre realizavam a mudança de decúbito.Nas úlceras em estágio II a utilização de óleos vegetais na ferida era realizada sempre por 10 (40%enfermeiros e o curativo de hidrocolóide nunca era utilizado por 12 (57,1% enfermeiros. Em UP com necrose alimpeza com povidine era realizada por 4 (17,4% enfermeiros às vezes. Para o desbridamento, 16 (64% àsvezes utilizavam papaína e 15 (71,4% às vezes utilizavam colagenase. Em úlceras com tecido de granulaçãosempre era utilizado o soro fisiológico por 25 (100% enfermeiros. Houve variação nas práticas para otratamento da UP e falta de adesão às diretrizes.

Mortalidad por causas externas en Medellín, 1999-2006

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Doris Cardona Arango

2008-01-01

Full Text Available Caracterizar el comportamiento de la mortalidad por causas externas en la ciudad de Medellín, Colombia, entre 1999-2006, según sexo, edad y causa básica de muerte fue el objetivo de este estudio descriptivo longitudinal, con fuente de información secundaria de 22 128 registros de defunción por causas externas. El análisis realizado es univariado y bivariado por sexo, grupos de edad y causa de muerte. Las causas externas registradas en el periodo fueron: 72.9 por ciento por homicidio; 15.3 por ciento, accidente de transporte; 7.3 por ciento, traumatismos; 4.2 por ciento, por suicidio, y por otras causas, 0.4 por ciento. La mayor tasa de mortalidad se presentó en el grupo de edad de 20 a 24 años (27.6 por cien mil habitantes, hecho que merece especial consideración por las implicaciones sociales, familiares y laborales que representa el fallecimiento de una persona en su etapa productiva.

Apendicitis por Paracoccidioides brasiliensis

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Ana Beatriz MUÑOZ URRIBARRI

2006-01-01

Full Text Available La paracoccidioidomicosis es la micosis más prevalente en Sudamérica. La forma aguda afecta el sistema fagocítico mononuclear de niños y personas inmunocomprometidas. El compromiso gastrointestinal es frecuente y su patogenia implica diseminación hematógena y linfática. La linfadenomegalia abdominal causa obstrucción intestinal y abdomen agudo. En este artículo damos a conocer el caso de un niño con compromiso gastrointestinal por apendicitis. Este es el primer caso reportado de apendicitis por esta patología. (Rev Med Hered 2006;17:58-60.

Tatuaje por amalgama. Reporte de un caso

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Luis Fang Mercado

2012-01-01

Full Text Available El tatuaje por amalgama se origina por el depósito en el tejido conectivo subepitelial de fragmentos de amalgama resultado de procedimientos iatrogénicos por parte del operador. La profundidad a la que se encuentren albergados los residuos de este material influye en la presentación clínica de las lesiones. Radiográficamente se pueden identificar los fragmentos mientras tengan diámetros razonables; histológicamente se pueden observar las partículas de amalgama como gránulos oscuros, sólidos e irregulares dispuesto entre los haces de colágeno y vasos sanguíneos. Este artículo refiere el caso clínico de un paciente que presentó pigmentación por amalgama en mucosa vestibular, originada por una porción de amalgama usada como material obturador en una apicectomía del 11 realizada con anterioridad. Teniendo en cuenta las consideraciones clínicas y radiográficas se optó por realizar una segunda apicectomía con obturación retrógrada con MTA del 11. Durante el procedimiento quirúrgico se cureteó y adelgazó la cara interna del colgajo mucoperióstico para tratar de disminuir el grado de pigmentación.

AcEST: DK953214 [AcEST

Lifescience Database Archive (English)

Full Text Available hit_id Q8S3M2 Definition tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla...ducing significant alignments: (bits) Value tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azoll... Metallothionein OS=Amaranthus cruentus PE... 41 0.026 >tr|Q8S3M2|Q8S3M2_AZOFI Metallothionein-like protein 2 OS=Azolla

Protein (Cyanobacteria): 175822 [PGDBj - Ortholog DB

Lifescience Database Archive (English)

Full Text Available agen triple helix repeat-containing protein 'Nostoc azollae' 0708 MRLIEDGEDGEDGEDGEDGEDGEDGEDGEDGEDGEDGEDGEDGGEIFLMPYALCPMPYALCPMPYALCPMPYALCPMPYALCPMPYAQNQDFSHPNRESSVKLFSSVAPKP ...

La pintura vista por un pintor joven

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Fuentes Pozo, Pedro

2000-01-01

Full Text Available Not available

El pintor se define a lo largo del tiempo como un artista en mutación influenciado por la sociedad de su momento y por su propio mundo interior Esto ha contribuido a la creación de distintos estilos pictóricos y a una evolución que conlleva la despreocupación por el aspecto formal en aras de una introspección al mundo interior En el cambio constante se refleja la búsqueda del artista que valida la intemporalidad del arte. Así, el verdadero artista sobrevive al aplauso o rechazo de la crítica, convirtiéndose en un verdadero hombre renancentista preocupado por el hallazgo del conocimiento universal.

Experiência inicial com terapia por pressão negativa por instilação em feridas complexas

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Dimas André Milcheski

Full Text Available RESUMO Objetivo: relatar a experiência inicial com a terapia por pressão negativa por instilação em feridas complexas infectadas ou contaminadas. Métodos: a terapia por pressão negativa por instilação utilizada foi o V.A.C. Ulta com instilação Veraflo (Kinetic Concepts, Inc. O modo de operação foi contínuo com pressão sub-atmosférica ajustada em 125 mmHg por duas horas e instilação entre as pausas. O tempo de instilação foi de 20 minutos (tempo de contato do agente tópico com a ferida e a substância instilada foi solução salina padrão a 0,9%. Após obtenção de preparo adequado da ferida, ela foi coberta com enxerto ou retalho. Resultados: foram operados dez pacientes com feridas complexas contaminadas ou infectadas. O número médio de trocas da TPNi foi 1,4, o número médio total de cirurgias foi de 2,4, o intervalo até a cobertura da ferida foi de 6,3 dias e o intervalo até a alta foi de 11,4 dias. Conclusão: a comparação da terapia por pressão negativa por instilação com dois estudos prévios (controle histórico evidenciou um tempo de internação menor, favorecendo a TPNi. Este estudo teve um caráter inicial, fazendo-se necessário conduzir um trabalho randomizado e controlado para confirmar a eficácia desta terapia e verificar a sua custo-efetividade.

Neuropatia experimental por DDT: análise de nervo por microdissecção de fibras

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Edison Matos Nóvak

1984-09-01

Full Text Available Estudou-se o nervo gênito-femural do rato albino submetido a intoxicação crônica por DDT, administrado por 180 dias na dose de 5 mg/kg de peso via oral. Os resultados mostraram proporção anormal de fibras tipo C, sendo sugerido ocorrer degeneração tipo axonal determinada pelo DDT.

Ptose palpebral causada por Paquidermoperiostose

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Patricia Regina de Pinho Tavares

2014-08-01

Full Text Available A paquidermoperiostose é uma síndrome caracterizada por acometimento cutâneo e ósseo, e em alguns casos ocorre comprometimento palpebral leve. É uma síndrome rara, idiopática ou hereditária, com provável herança autossômica dominante de penetrância variável. Descreve-se o caso de um paciente com ptose grave por paquidermoperiostose elucidando sua fisiopatologia e conduta cirúrgica aplicada.

Suppression of cytochrome P450 reductase (POR) expression in hepatoma cells replicates the hepatic lipidosis observed in hepatic POR-null mice.

Science.gov (United States)

Porter, Todd D; Banerjee, Subhashis; Stolarczyk, Elzbieta I; Zou, Ling

2011-06-01

Cytochrome P450 reductase (POR) is a microsomal electron transport protein essential to cytochrome P450-mediated drug metabolism and sterol and bile acid synthesis. The conditional deletion of hepatic POR gene expression in mice results in a marked decrease in plasma cholesterol levels counterbalanced by the accumulation of triglycerides in lipid droplets in hepatocytes. To evaluate the role of cholesterol and bile acid synthesis in this hepatic lipidosis, as well as the possible role of lipid transport from peripheral tissues, we developed a stable, small interfering RNA (siRNA)-mediated cell culture model for the suppression of POR. POR mRNA and protein expression were decreased by greater than 50% in McArdle-RH7777 rat hepatoma cells 10 days after transfection with a POR-siRNA expression plasmid, and POR expression was nearly completely extinguished by day 20. Immunofluorescent analysis revealed a marked accumulation of lipid droplets in cells by day 15, accompanied by a nearly 2-fold increase in cellular triglyceride content, replicating the lipidosis seen in hepatic POR-null mouse liver. In contrast, suppression of CYP51A1 (lanosterol demethylase) did not result in lipid accumulation, indicating that loss of cholesterol synthesis is not the basis for this lipidosis. Indeed, addition of cholesterol to the medium appeared to augment the lipidosis in POR-suppressed cells, whereas removal of lipids from the medium reversed the lipidosis. Oxysterols did not accumulate in POR-suppressed cells, discounting a role for liver X receptor in stimulating triglyceride synthesis, but addition of chenodeoxycholate significantly repressed lipid accumulation, suggesting that the absence of bile acids and loss of farnesoid X receptor stimulation lead to excessive triglyceride synthesis.

Consanguinidad por isonimia en Salta

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Albeza, María V.

2007-01-01

Full Text Available Se estimó el coeficiente de parentesco por isonimia para localidades de la Puna, Valle Calchaquí y Valle de Lerma, a fin de evaluar diferentes factores evolutivos que podrían estar afectando la composición genética de la población. A partir de los apellidos de las parejas consignadas en fuentes primarias de información, se estimó la isonimia conyugal o marital, el coeficiente total Ft y sus componentes Fr (inbreeding azaroso y Fn (inbreeding no azaroso. De las localidades estudiadas, en la Puna se ha detectado sólo una pareja isónima en una de ellas, en el Valle Calchaquí, tres y ninguna en el Valle de Lerma. Tanto en el Valle Calchaquí como en el de Lerma, se han estimado valores negativos de Ft, y en la Puna se registran los valores más elevados. En las localidades estudiadas no se cumple el supuesto de transmisión patrilineal de apellidos por lo que los valores de Fr y por ende de Ft podrían estar subestimados. Es por ello que sería necesario contar con información desde otras vertientes metodológicas para corroborar, complementar y manejar cuidadosamente el análisis de los datos y las conclusiones que se obtienen.

Nefrectomía simple por puerto único (LESS) asistida por robot (da Vinci)

OpenAIRE

CASTILLO C,OCTAVIO A; VIDAL M,IVAR; SEPÚLVEDA T,FRANCISCO

2011-01-01

Introducción: La cirugía mínimamente invasiva en urología avanza rápidamente y la cirugía laparo-endoscópica a través de puerto único (LESS) no es la excepción. Esta técnica por vía laparoscópica presenta mucha dificultad y requiere de un cirujano laparoscópico experimentado debido a la falta de triangulación y el cruce de los instrumentos. Los beneficios del sistema quirúrgico da Vinci® han sido introducidos recientemente en LESS. Presentamos dos casos de nefrectomía LESS asistida por robot....

Análisis de costos por ausentismo laboral atribuibles a licencias médicas por enfermedad. Hospital Nacional Arzobispo Loayza 2015

OpenAIRE

Jave Escalante, Gladys Lizeth

2015-01-01

Determina el costo generado por el ausentismo laboral atribuible a licencias médicas por enfermedad en el Hospital Nacional Arzobispo Loayza 2015. METODOLOGÍA: Estudio no experimental. La muestra estuvo conformada por 118 médicos asistenciales y personal de enfermería. Para el análisis de los costos se utilizó el costo de tiempo perdido del paciente, ingresos dejados de percibir por el hospital y descuento económico al trabajador. Además se realizó un análisis económico y de sensibilidad. ...

Indice por Materias

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Montoya H Luz Marina

1982-09-01

Full Text Available Un índice es una lista de palabras o frases indicadores asociados que permite la ubicación de material al interior de un libro o una publicación, en este caso será por el nombre de la materia.

Anticaries Activity of Azolla pinnata and Azolla rubra | Prashith ...

African Journals Online (AJOL)

http://dx.doi.org/10.4314/star.v3i3.21 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News. OTHER RESOURCES... for Researchers · for Journals · for Authors · for Policy Makers ...

Protein (Cyanobacteria): 298492611 [PGDBj - Ortholog DB

Lifescience Database Archive (English)

Full Text Available 551115:2260 ... 50S ribosomal protein L20 'Nostoc azollae' 0708 MTRVKRGNVARKRRNKILKLAKGFRGSHSTLFRTAHQQVMKALRSAYRDRKKKKRDFRRLWITRINAASRQNGLSYSQLIGNLKKANVELNRKMLAQLAVLDPASFAKVAELANSVKA

CYANOBACTERIA FOR MITIGATING METHANE EMISSION FROM SUBMERGED PADDY FIELDS

Energy Technology Data Exchange (ETDEWEB)

Upasana Mishra; Shalini Anand [Department of Environmental Studies, Inderprastha Engineering College, Sahibabad, Ghaziabad (India)

2008-09-30

Atmospheric methane, a potent greenhouse gas with high absorption potential for infrared radiation, is responsible for one forth of the total anticipated warming. It is forming a major part of green house gases, next after carbon dioxide. Its concentration has been increasing alarmingly on an average at the rate of one percent per year. Atmospheric methane, originating mainly from biogenic sources such as paddy fields, natural wetlands and landfills, accounts for 15-20% of the world's total anthropogenic methane emission. With intensification of rice cultivation in coming future, methane emissions from paddy fields are anticipated to increase. India's share in world's rice production is next after to China and likewise total methane emission from paddy fields also. Methane oxidation through planktophytes, particularly microalgae which are autotrophic and abundant in rice rhizospheres, hold promise in controlling methane emission from submerged paddy fields. The present study is focused on the role of nitrogen fixing, heterocystous cyanobacteria and Azolla (a water fern harboring a cyanobacterium Anabaena azollae) as biological sink for headspace concentration of methane in flooded soils. In this laboratory study, soil samples containing five potent nitrogen fixer cyanobacterial strains from paddy fields, were examined for their methane reducing potential. Soil sample without cyanobacterial strain was tested and taken as control. Anabaena sp. was found most effective in inhibiting methane concentration by 5-6 folds over the control. Moist soil cores treated with chemical nitrogen, urea, in combination with cyanobacteria mixture, Azolla microphylla or cyanobacteria mixture plus Azolla microphylla exhibited significance reduction in the headspace concentration of methane than the soil cores treated with urea alone. Contrary to other reports, this study also demonstrates that methane oxidation in soil core samples from paddy fields was stimulated by

Mortalidad intrahospitalaria por accidente cerebrovascular

OpenAIRE

Federico Rodríguez Lucci; Virginia Pujol Lereis; Sebastián Ameriso; Guillermo Povedano; María F. Díaz; Alejandro Hlavnicka; Néstor A. Wainsztein; Sebastián F. Ameriso

2013-01-01

La mortalidad global por accidente cerebrovascular (ACV) ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Str...

Prioritizing conservation seed banking locations for imperiled hemlock species using multi-attribute frontier mapping

Science.gov (United States)

John M. Hastings; Kevin M. Potter; Frank H. Koch; Mark Megalos; Robert M. Jetton

2017-01-01

Hemlock woolly adelgid (Adelges tsugae Annand) (HWA) is an invasive forest insect sweeping across the native range of eastern (Tsuga canadensis [L.] Carr.) and Carolina (Tsuga caroliniana Engelm.) hemlocks, threatening to severely reduce eastern hemlock extent and to push Carolina hemlock to extirpation. HWA poses a significant threat to these eastern US natives, now...

CARACTERÍSTICAS DA VIOLÊNCIA SEXUAL SOFRIDA POR CRIANÇAS ASSISTIDAS POR UM PROGRAMA DE APOIO

Directory of Open Access Journals (Sweden)

KELLY LINHARES VASCONCELOS

2010-01-01

Full Text Available En Brasil, las estadísticas de la violencia sexual contra niños están lejos de reflejar la verdadera realidad actual debido a la baja notificación de los casos. La finalidad de este estudio fue caracterizar el abuso sexual sufrido por niños asistidos por el Programa Sentinela y el perfil del agresor, en Sobral-Ceará, en el periodo que va del 2002 al 2006. La muestra no probabilística intencional fue compuesta por 50 víctimas de abuso sexual y de las mismas, el 66% es del sexo femenino, con predominio de rango de edad entre 8-12 años incompletos, (58%; en el 36% de los casos los padres están separados, siendo la madre la principal responsable por la familia (62%. La mayoría de los agresores es del sexo masculino (78%. En el ambiente fuera de la familia los agresores son conocidos o amigos de la familia (14%; dentro del seno familiar el padrastro es identificado como siendo el agresor más frecuente (18%. Los datos destacan características similares a las de otros estudios, definiendo una cierta igualdad en este tipo de violencia.

Absorption and degradation of 14C-2, 4-D by some free-floating aquatic weeds

International Nuclear Information System (INIS)

Singh, S.P.

1980-01-01

Plants of Salvinia, Lemna, Azolla and Limnobium, which are free-floating aquatic weeds, were grown separately in glass dishes containing initially 400 ml of nutrient solution and 2 μCi of 14 C-2,4-D under controlled conditions of temperature, light and relative humidity. The total uptake of 2,4-D by these plant species increased with the increasing duration of exposure to herbicide. 2,4-D uptake, calculated on per unit dry weight of weed, was maximum in case of Limnobium, followed by Salvinia, Lemna and Azolla. After 20 days of treatment, the highest radioactivity (24%) was obtained in the organic fraction of the extracts of Limnobium and Azolla; followed by Salvinia (8%) and Lemna (6%). In a separate experiment, root uptake and subsequent translocation of 14 C-2,4-D was also studied. At all the stages of sampling, more than half to 3/4th of the absorbed 14 C-2,4-D was found in the roots, and the remaining was present in the shoot. (author)

Vivencias psicosociales reveladas por niños que reciben tratamiento con quimioterapia por cáncer

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BLANCA CECILIA VANEGAS DE AHOGADO

2009-12-01

Full Text Available Se realizó un estudio cualitativo con el propósito de descubrir las vivencias psicosociales de niños y niñas de 9 a 12 años que recibían tratamiento con quimioterapia por cáncer. La recolección de la información se hizo mediante encuentros lúdicos con el apoyo de algunas preguntas básicas que facilitaron las revelaciones narrativas. Tres aspectos se destacan en los hallazgos del estudio: vivencias desfavorables, vivencias relacionadas con la autoestima y vivencias favorables; las dos primeras, de diversa manera, afectan en estos niños su vida personal, familiar, escolar y, en general, todo su entorno. Es de resaltar que, como consecuencia de la caída del cabello, con frecuencia han sido objeto de burla y de rechazo por sus compañeros de estudio, lo que produce el más notorio efecto sobre su autoimagen; por otra parte, el ausentismo escolar conlleva dificultades académicas y sentimientos de tristeza en estos niños, situación que empeora cuando, por motivos de tratamiento, su lugar de residencia está alejado de la ciudad, viéndose sometidos a largos periodos de separación, no solo de su familia sino de sus pares. Se concluye que la mayor parte de las revelaciones son impactantes por su gran contenido de sufrimiento y dolor para estos niños, lo que demuestra la urgencia de retomar los hallazgos del estudio para orientar el cuidado de enfermería de manera más integral y apoyar para que se haga lo propio en el hogar y en las instituciones educativas.

Using climate and genetic diversity data to prioritize conservation seed banking for imperiled hemlock species

Science.gov (United States)

J.M. Hastings; K.M. Potter; F.H. Koch; M.A. Megalos; R.M. Jetton

2017-01-01

Hemlock woolly adelgid (HWA, Adelges tsugae) is an invasive forest insect that has caused mortality of eastern (Tsuga canadensis) and Carolina hemlock (T. caroliniana) at an alarming rate. Now infesting 19 states and over 400 counties of the eastern United States, HWA poses a significant threat to native host species. The current biological and chemical methods for...

Validating the Operational Draft Regional Guidebook for the Functional Assessment of High-Gradient Ephemeral and Intermittent Headwater Streams in Western West Virginia and Eastern Kentucky

Science.gov (United States)

2014-04-01

blackgum, wild black cherry (Prunus serotina), sweet cherry (Prunus avium), slippery elm (Ulmus rubra), sourwood (Oxydendrum arboreum), red maple, and...virginiana), American hornbeam (Carpinus caroliniana), and slippery elm . Buffalo nut (Pyrularia pubera), wild hydrangea (Hydrangea arborescens...Pinus strobus), wild black cherry, boxelder (Acer negundo), sycamore, black locust (Robinia pseudo-acacia), slippery elm , and white ash. The shrub

Pedro Teixeira y su viaje por Mesopotamia

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Fuente del Pilar, José Javier

2005-04-01

Full Text Available Pedro Teixeira es un integrante notable de la ilustre nómina de los viajeros portugueses que, a finales del s, XVI y principios del XVII, ensancharon para Occidente las fronteras del mundo. Su conocimiento en España se debe a la publicación en 1994 de su obra «Relaciones del Origen, Descendencia y Sucesión de los Reyes de Persia, y de Harmuz, y de un viaje hecho por el autor dende la India hasta Italia por tierra», en edición realizada por el profesor Eduardo Barajas Sala, lamentablemente fallecido en 1997. En este artículo se ofrece una reseña biográfica de Pedro Teixeira, y un análisis del viaje narrado por el autor en la última parte de sus «Relaciones »: el que desde Ormuz le conducirá, a través de Mesopotamia, hasta la costa del Mediterráneo.…

Violência e mortes por causas externas

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Graciete Oliveira Vieira

2003-02-01

Full Text Available Através de um estudo ecológico caracterizou-se a violência e as mortes por causas externas em Salvador e Bahia utilizando-se dados da Fundação Nacional de Saúde-Ministério da Saúde, dos registros de mortalidade e das estimativas populacionais do IBGE. O risco de morrer por homicídio no Brasil é 3 vezes o do Estados Unidos, chegando a ser 40 vezes superior ao do Japão. Homicídio foi a primeira causa de anos potenciais de vidas perdidos (13,4% no Brasil (1997, seguido por acidentes de trânsito (10,6%. Causas externas foi a segunda causa de morte em Salvador e Bahia (1996. A violência tem raízes sócio-culturais e político-ideológicas e pode ser prevenida por ações intersetoriais e multidisciplinares.

Associação entre violência por parceiro íntimo contra a mulher e infecção por HIV

Directory of Open Access Journals (Sweden)

Claudia Barros

2011-04-01

Full Text Available OBJETIVO: Analisar a associação entre a violência por parceiro íntimo contra mulheres e a infecção ou suspeita de infecção pelo vírus da imunodeficiência humana (HIV. MÉTODOS: Estudo transversal com base em dados de questionários aplicados face-a-face e de prontuários médicos de 2.780 mulheres de 15 a 49 anos, atendidas em unidades do sistema único de saúde da Grande São Paulo, SP, em 2001-2002. As mulheres foram categorizadas em: usuárias em tratamento por serem "soropositivas para o HIV", com "suspeita de HIV" e aquelas que procuraram os serviços por outros motivos. A violência por parceiro íntimo contra mulheres na vida foi categorizada por gravidade e recorrência dos episódios de violência. A associação com o desfecho foi testada pelo modelo de Poisson com variância robusta e ajustada por variáveis sociodemográficas, sexuais e reprodutivas. RESULTADOS: A prevalência de violência foi de 59,8%. Sofrer violência reiterada e grave apresentou maior associação de infecção confirmada pelo HIV (RP = 1,91. A violência independente da gravidade e da recorrência dos episódios apresentou maior associação para a suspeita de infecção por HIV (RP = 1,29. CONCLUSÕES: A violência por parceiro íntimo contra mulheres tem papel relevante nas situações de suspeita e confirmação da infecção pelo HIV, sendo essencial incluir sua detecção, controle e prevenção como parte da atenção integral à saúde das mulheres.

Predominant porB1A and porB1B genotypes and correlation of gene mutations with drug resistance in Neisseria gonorrhoeae isolates in Eastern China

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Tang Renxian

2010-11-01

Full Text Available Abstract Background Variations of porB1A and porB1B genes and their serotypes exist in Neisseria gonorrhoeae isolates from different geographical areas, and some site mutations in the porB1B gene correlate with drug resistance. Methods The β-lactamase production of N. gonorrhoeae isolates was determined by paper acidometric test and nitrocefin discs. The porB1A and porB1B genes of 315 non-penicillinase-producting N. gonorrhoeae (non-PPNG strains were amplified by PCR for sequencing to determine serotypes and site mutations. A duplex PCR was designed to simultaneously detect both porB1A and porB1B genes. Penicillin and tetracycline resistance was assessed by an in vitro drug sensitivity test. Results Of the N. gonorrhoeae isolates, 31.1% tested positive for porB1A and 68.9% for porB1B genes. All the 98 porB1A+ isolates belonging to IA6 serotype with either no mutation at the 120 and 121 sites (88.8% or a D120G (11.2% mutation and were no resistance to both penicillin and tetracycline. Among the 217 porB1B+ isolates, 26.7%, 22.6% and 11.5% belonged to IB3, IB3/6 and IB4 serotypes, respectively. Particularly, two novel chimeric serotypes, IB3/6-IB2 and IB2-IB4-IB2, were found in 77 and 8 porB1B+ isolates. Two hundred and twelve (97.7% of the porB1B+ isolates were presented G120 and/or A121 mutations with 163 (76.9% at both sites. Interestingly, within the 77 porB1B+ isolates belonging to IB3/6-IB2 serotype, 15 were discovered to possess novel deletions at both A121 and N122 sites. All the replacement mutations at these sites in PorB1B were correlated with resistance and the deletion mutation showed the highest resistance. Conclusion N. gonorrhoeae isolates circulating in Eastern China include a sole PorB1A serotype (IA6 and five PorB1B serotypes. Multiple mutations in porB1B genes, including novel A121 and N122 deletions, are correlated with high levels of penicillin and tetracycline resistance.

Conservación por calor

OpenAIRE

Cobos García, Angel; Díaz Rubio, Olga

2011-01-01

Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos por calor. Este método permite destruír ...

Las cosas por su nombre

OpenAIRE

Storani, Emilia

2017-01-01

El artículo propone indagar sobre los modos y diferentes formatos que se utilizan tanto en la escritura como en la lectura, para articular con las luchas por la identidad de género. La Ley de Identidad de Género ha sido un puntapié clave para pensarnos a nosotros mismos culturalmente y para pensar a los demás. Pero, ¿cómo mencionamos, escribimos y leemos las diferentes identidades? La escritura, también es un mundo transformador para quienes bregan por una sociedad más libre y sin prejuicios....

Diverticulitis yeyunal perforada por enterolito.

OpenAIRE

Marenco De la Cuadra, Beatriz; Gomez-Rosado, Juan-Carlos; Capitan-Morales, Luis-Cristobal; Valdés Hernández, Javier; Reyes-lopera, N.J. De los

2012-01-01

La diverticulosis yeyunal es una enfermedad adquirida rara. Casi el 60-70% keeps asymptomátic or Con síntomas crónicos inespecíficos, aunque puede presentarse como un abdomen agudo. La perforación debida a enterolitos es una causa extremadamente rara do complicación, y puede producirse por la impactación de ésta contra la pared intestinal. Presentamos caso de un varón de 82 años que acude a urgencias por un dolor súbito abdominal, difuso, con irritación peritoneal, leucocitosis con neutro...

Por y para en los manuales de ELE

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Sidoti, Rossana

2008-12-01

Full Text Available La oposición por / para es una de las cuestiones gramaticales que comportan mayor dificultad a la hora de acercarse al estudio del español como L2 sobre todo cuando remiten a conceptos lingüísticos difíciles de entender por no tener ésta referente alguno en el mundo extralingüístico. Si, por un lado, nos resulta fácil entender lo que tiene un referente en el mundo concreto; por otro, no podemos advertir el referente extralingüístico de preposiciones como por / para, si este no existe. Si las preposiciones son elementos abstractos, difíciles de aferrar de por sí, podemos sólo examinar los elementos que éstas ponen en relación y en qué contextos esta relación se determina. Para poder utilizar con precisión las dos preposiciones, es importante no reducirlas a una sola preposición como ocurre en otros idiomas, y sobre todo no relacionarlas sólo a los conceptos de causa y finalidad. Este trabajo se propone individualizar los manuales de español como lengua extranjera más utilizados en las universidades italianas para luego comparar las distintas fuentes de información sobre por / para y exponer comentarios, reflexiones y sugerencias sobre el tema con el fin de precisar en qué medida se puede mejorar lo que los manuales reducen o generalizan, puesto que para los estudiantes de ELE estos representan una herramienta valiosa a la que acudir.

Pronóstico de la diarrea por rotavirus

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Mota-Hernández Felipe

2001-01-01

Full Text Available Objetivo. Comparar la gravedad de la diarrea por rotavirus (RV y por no rotavirus. Material y métodos. Estudio transversal en 520 lactantes con diarrea aguda, efectuado entre octubre de 1994 y marzo de 1995 en siete centros del primer nivel de atención en cinco estados de México. El diagnóstico de RV se realizó con ensayo inmunoenzimático o por electroforesis. El análisis se hizo a través de medidas de tendencia central. Los resultados se presentan como promedio y desviación estándar o mediana o variación. Resultados. Se aisló RV en 264 lactantes (50.7% con predominio en varones de 6 meses a un año. Las manifestaciones clínicas fueron significativamente diferentes entre el grupo rotavirus positivo y el grupo rotavirus negativo en mediana de evacuaciones por 24 horas, frecuencia de vómitos, temperatura > 38° C, deshidratación y calificación de gravedad, respectivamente. Conclusiones. Estos resultados mostraron peor pronóstico por mayor gravedad de la diarrea por RV en lactantes, con relación a otra etiología. El texto completo en inglés de este artículo está disponible en: http://www.insp.mx/salud/index.html

Miasis cutanea por cordylobia anthropophaga

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Alkorta Gurrutxaga Miriam

2001-01-01

Full Text Available El incremento progresivo en el número de personas que viajan a países tropicales ha hecho que las enfermedades importadas adquieran una relevancia cada vez mayor. Las miasis (o infestaciones por larvas de moscas cutáneas se encuentran entre este tipo de enfermedades siendo especialmente frecuentes en países tropicales. A propósito de la observación de un caso de miasis cutánea masiva por Cordylobia antropophaga, que ocurrió en una mujer de 34 años de edad al volver de un viaje a Senegal, se ha efectuado una revisión de los casos de miasis cutáneas forunculoides importadas publicados en España, así como de la biología, patología, tratamiento y prevención de la miasis humana por Cordylobia anthropophaga. El caso referido, se caracterizó por la infestación con un número inusualmente elevado de larvas, no sospechándose su etiología hasta la fase final de la enfermedad. La emergencia continuada de larvas (se recogieron 91 generó en la paciente un estado de ansiedad importante. Finalmente, la eliminación de las larvas provocó una rápida mejoría de la paciente. Aunque los casos de miasis cutánea no tienen la gravedad de otras enfermedades importadas, su conocimiento es necesario desde el punto de vista preventivo, diagnóstico y terapeútico. Es importante proceder a la identificación morfológica de las larvas diferenciándolas de otro tipo de miasis con implicaciones terapéuticas diferentes.

Associação entre violência por parceiro íntimo contra a mulher e infecção por HIV Asociación entre violencia contra la mujer por pareja íntima e infección por VIH Association between intimate partner violence against women and HIV infection

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Claudia Barros

2011-04-01

Full Text Available OBJETIVO: Analisar a associação entre a violência por parceiro íntimo contra mulheres e a infecção ou suspeita de infecção pelo vírus da imunodeficiência humana (HIV. MÉTODOS: Estudo transversal com base em dados de questionários aplicados face-a-face e de prontuários médicos de 2.780 mulheres de 15 a 49 anos, atendidas em unidades do sistema único de saúde da Grande São Paulo, SP, em 2001-2002. As mulheres foram categorizadas em: usuárias em tratamento por serem "soropositivas para o HIV", com "suspeita de HIV" e aquelas que procuraram os serviços por outros motivos. A violência por parceiro íntimo contra mulheres na vida foi categorizada por gravidade e recorrência dos episódios de violência. A associação com o desfecho foi testada pelo modelo de Poisson com variância robusta e ajustada por variáveis sociodemográficas, sexuais e reprodutivas. RESULTADOS: A prevalência de violência foi de 59,8%. Sofrer violência reiterada e grave apresentou maior associação de infecção confirmada pelo HIV (RP = 1,91. A violência independente da gravidade e da recorrência dos episódios apresentou maior associação para a suspeita de infecção por HIV (RP = 1,29. CONCLUSÕES: A violência por parceiro íntimo contra mulheres tem papel relevante nas situações de suspeita e confirmação da infecção pelo HIV, sendo essencial incluir sua detecção, controle e prevenção como parte da atenção integral à saúde das mulheres.OBJETIVO: Analizar la asociación entre la violencia contra mujeres por pareja íntima y la infección o sospecha de infección por el virus de inmunodeficiencia humana (VIH. MÉTODOS: Estudio transversal con base en datos de cuestionarios aplicados cara-a cara y de prontuarios médicos de 2.780 mujeres de 15 a 49 años, atendidas en unidades del sistema único de salud de la Gran Sao Paulo, Sureste de Brasil, en 2001-2002. Las mujeres fueron categorizadas en: usuarias en tratamiento por ser

Itinerarios Didácticos por la isla de Lanzarote

OpenAIRE

Becerra-Ramírez, Rafael; González Cárdenas, Elena; Gosálvez, Rafael U.; Escobar Lahoz, Estela; Dóniz-Páez, Javier

2013-01-01

Con la confección de esta guía de itinerarios didácticos por la isla de Lanzarote pretendemos contribuir a un mayor conocimiento de las características geográficas de este espacio dominado por las formas volcánicas que caracterizan un paisaje modificado por la mano del hombre que convive con los volcanes y los usa, tradicionalmente como soporte de sus cultivos, y modernamente como base de la industria turística. Los itinerarios didácticos por la isla de Lanzarote son la adaptación de los t...

Signos Vitales de los CDC-Muertes por intoxicación por alcohol (Alcohol Poisoning Deaths)

Centers for Disease Control (CDC) Podcasts

2015-01-06

Este podcast se basa en la edición de enero del 2015 del informe Signos Vitales de los CDC. En los Estados Unidos, mueren en promedio seis personas cada día debido a la intoxicación por alcohol. Infórmese sobre lo que puede hacer para prevenir los atracones de alcohol y las intoxicaciones por alcohol.  Created: 1/6/2015 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 1/6/2015.

Topoplastia de Cvintal assistida por laser de femtossegundo

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Alexandre Takayoshi Ishizaki

2013-06-01

Full Text Available Apresentamos um relato de astigmatismo tardio progressivo pós-transplante de córnea para ceratocone, associado à afinamento periférico na junção doador-receptor, o que presumidamente pode ser considerado como recorrência da ectasia. O caso foi tratado por meio de Topoplastia de Cvintal assistida por laser de femtossegundo para a confecção da incisão com geometria "top hat", seguido de sutura com ajuste per-operatório guiado por ceratoscopia.

Micetoma por Nocardia brasiliensis: reporte de caso

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Miriam Guevara R

2003-07-01

Full Text Available Se presenta el caso de un paciente peruano, agricultor, con una infección cutánea de origen traumático causada por Nocardia brasiliensis, que evolucionó hacia la amputación del miembro inferior afectado. El diagnóstico se realizó por examen directo y cultivo del espécimen.

Mortalidad por envenenamiento en niños

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Híjar Martha

1998-01-01

Full Text Available Objetivo. Conocer el panorama de las muertes por envenenamiento en niños de 0-14 años ocurridas en la República mexicana, entre 1979 y 1994. Material y métodos. Se utilizaron fuentes secundarias. Las variables analizadas fueron: edad, sexo, año, causa externa de traumatismos y envenenamientos, de la IX Clasificación Internacional de Enfermedades: E850-E858, E860-E869 y E905. Mediante un modelo de regresión Poisson se analizaron tendencias por causa específica y se obtuvieron riesgos relativos según edad, sexo y entidad federativa. Resultados. Hubo un total de 11 272 defunciones en menores de 15 años; las principales causas fueron el envenenamiento y las reacciones tóxicas causadas por plantas y animales venenosos (E905, el envenenamiento accidental por gas de uso doméstico y por monóxido de carbono (E868 y el envenenamiento accidental por otras drogas (E858. El grupo de edad que presentó los mayores riesgos, para las causas mencionadas, fue el de menores de un año con un riesgo relativo (RR de 29.6, IC95% 29.2-33.4; RR 3.47, IC95% 2.86-4.22, y RR 31.86, IC95% 24.8-40.9. El riesgo fue similar en ambos sexos, salvo para la causa E905. El estado de Aguascalientes se situó sistemáticamente entre los de mayor riesgo para todas las causas analizadas, mientras que Nuevo León siempre se ubicó entre los de riesgo más bajo. Conclusiones. El envenenamiento constituye una importante causa de muerte en los niños; el riesgo se incrementa al disminuir la edad. Considerando que esas muertes son potencialmente evitables y que la mayor parte de los envenenamientos ocurren en el hogar, para prevenirlos, se recomienda a los familiares vigilar y mantener fuera de peligro al niño. Por otra parte, la multicausalidad del fenómeno requiere que su prevención se realice desde una perspectiva multidisciplinaria que genere una cultura y un ambiente de seguridad en la sociedad.

Selección de Recursos Humanos por Competencias

OpenAIRE

Sánchez Domingo, Cristina

2013-01-01

Los objetivos de este trabajo son, por un lado conocer en qué consisten los procesos de valoración y selección de personas desde el enfoque de las competencias laborales. Para ello, ha sido preciso profundizar en el estudio del concepto de “competencia laboral”, y comprender qué es la Gestión de Recursos Humanos por Competencias, en cuyo seno se encuentra la propia Selección de Recursos Humanos. Por otra parte, un segundo objetivo del trabajo es conocer el grado de implantación de la Selecció...

Hemlock woolly adelgid in the southern Appalachians: Control strategies, ecological impacts, and potential management responses

Science.gov (United States)

James M. Vose; David N. Wear; Albert E. Mayfield; C. Dana Nelson

2013-01-01

Hemlock woolly adelgid (Adelges tsugae Annad; or HWA) is a non-native invasive pest that attacks and kills eastern hemlock (Tsuga canadensis (L.) Carrière) and Carolina hemlock (Tsuga caroliniana Engelm.). Hemlock is a ‘‘foundation species’’ due to its strong influence on ecosystem structure and function,...

Engineering and Environmental Study of DDT Contamination of Huntsville Spring Branch, Indian Creek, and Ajacent Lands and Waters, Wheeler Reservoir, Alabama. Revision

Science.gov (United States)

1984-05-04

27. Endangered, Threatened and Special Concern Plants Possibly Occurring on Wheeler National Wildlife Refuge ALABAMA FEDERAL SPECIES FAMILY STATUS1...SSC NL Oxalis grandis Oxalidaceae SSC NL Actaea pachypoda Ranunculaceae SSC NL Anemone caroliniana Ranunculaceae SSC NL Veronica anoacalis - agutc...River Valley base camps and seasonally dispersing into small groups of nuclear families to exploit the uplands. Later, during the Woodland period, the

Tallado de hélices por el método de copiado por proyección

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José Vicente Fierro Vasco

1983-01-01

Full Text Available Este dispositivo fue diseñado como parte de la investigación sobre Aerogeneradores que se está llevando a cabo en el Departamento de Ingeniería Mecánica, cuyo investigador principal es el Ing. Julio Mario Rodríguez Devis. Como parte inicial de la investigación se adecuó un túnel situado en el Laboratorio de Hidráulica para hacer las pruebas de modelos. En la construcción de dichos modelos se requiere una buena precisión en la hechura de las aspas del molino, en especial por el tamaño reducido de liste. Se debe garantizar que el perfil aerodinámico se conserve a lo largo del aspa, por lo que se requiere de un dispositivo capaz de tallar los álabes con la precisión y rapidez necesarias. Los resultados del trabajo fueron presentados al concurso del premio Worthington de la Ingeniería Colombiana 1982 (Categoría estudiantes, por los estudiantes que trabajaron en el proyecto, siendo acreedores al primer puesto.

CARACTERIZAÇÃO ESPECTRAL DA CANA-DE-AÇÚCAR INFECTADA POR NEMATOIDES E MIGDOLUS FRYANUS POR ESPECTRORRADIOMETRIA DE CAMPO

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George Deroco Martins

Full Text Available O cultivo da cana-de-açúcar no Brasil, embora assistido por técnicas modernas de plantio, é alvo constante de parasitas do sistema radicular. Por registrar seletivamente o fluxo espectral da radiação eletromagnética refletida pela vegetação, o sensoriamento remoto tornou-se uma poderosa ferramenta na detecção das plantas infectadas por patógenos do solo. Com o objetivo de caracterizar espectralmente a cana-de-açúcar sadia e infectada por nematoides e pela larva do besouro Migdolus fryanus, foram tomadas medidas radiométricas in situ e geradas curvas hiperespectrais de plantas sadias e infectadas. Técnicas específicas de análise espectral, como a determinação da posição da borda do vermelho limítrofe (Red Edge Position Determination - REPD e diferentes índices espectrais foram avaliados para discriminar as três ocorrências. As curvas de reflectância mostraram diferenças em magnitude principalmente nos comprimentos de onda do vermelho e infravermelho próximo e, assim como a determinação do REP e os índices de clorofila b, NDVI, MCARI e TCARI, permitiram distinguir apenas entre plantas sadias e infectadas. As razões espectrais sensíveis aos pigmentos clorofila a e carotenoides, porém, discriminaram as três ocorrências, inclusive plantas infectadas por nematoides e Migdolus fryanus. A melhor discriminação foi obtida com o índice de carotenoides, um pigmento fortemente relacionado com estresse da planta

Osteoporosis secundaria y Osteoporosis inducida por glucocorticoides (OIG

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Elías Forero Illera

2006-01-01

Full Text Available La osteoporosis es un problema de salud pública importante a nivel mundial, y su prevalencia está aumentando. La osteoporosis secundaria se puede producir por varias patologías y el uso de ciertos medicamentos. Los glucocorticoides son un grupo de fármacos usados extensamente en la práctica médica debido a su indiscutible utilidad. La osteoporosis inducida por glucocorticoides es un problema de salud pública. Aunque la patogénesis de la pérdida producida por los glucocorticoides en el hueso no se conoce totalmente, investigaciones recientes han proporcionado nuevas conocimientos en los mecanismos de estos fármacos a nivel celular y molecular. Diversas guías han sido propuestas por diversos grupos para el tratamiento de la OIG; desafortunadamente, las guías del tratamiento no se utilizan adecuadamente en los pacientes.

Principais gestos esportivos executados por jogadores de handebol

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Luiz Carlos Hespanhol Junior

2012-09-01

Full Text Available Este estudo teve como objetivo quantificar os principais gestos esportivos executados por jogadores profissionais de handebol. Para a mensuração quantitativa dos principais movimentos executados por cada jogador de handebol avaliado foram realizadas gravações de vídeo em todos os jogos. Foram realizados em média 1288,0 (DP = 190,7 gestos esportivos por jogo. Os armadores centrais realizaram em média 375,0 (DP = 83,7 gestos esportivos, e a posição de pivô 63,3 (DP = 21,2 gestos por jogo. As recepções e os passes foram os gestos mais executados, e a posição que mais realizou gestos esportivos na equipe de handebol avaliada foi o armador central, seguido do armador esquerdo e direito. O pivô foi a posição que menos realizou gestos esportivos.

Higiene mental: conferencia dictada por la Radiodifusora Nacional

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Francisco Gómez Pinzón

1941-01-01

tiene extraordinaria trascendencia para el país por sus vastas repercusiones sobre el futuro de nuestro pueblo, y que, sin embargo ha sido negligentemente olvidado por las autoridades y deliberadamente ignorado por los sectores cultos e ilustrados de nuestra sociedad. Me refería entonces a la curva ascendente que, no sólo entre nosotros sino en todos los países civilizados, han seguido en su propagación las enfermedades nerviosas y mentales, y que hace contraste con la disminución progresiva de las demás afecciones y en especial de las infecto-contagiosas, que están a punto de ser dominadas por la técnica cada día más perfecta de la medicina preventiva. Hoy quiero ocuparme de algunos aspectos de este mismo tema que apenas alcanzaron a ser esbozados en mi conferencia anterior.

Impacts of integrated nutrient management on methane emission, global warming potential and carbon storage capacity in rice grown in a northeast India soil.

Science.gov (United States)

Bharali, Ashmita; Baruah, Kushal Kumar; Baruah, Sunitee Gohain; Bhattacharyya, Pradip

2018-02-01

Rice soil is a source of emission of two major greenhouse gases (methane (CH 4 ) and nitrous oxide (N 2 O)) and a sink of carbon dioxide (CO 2 ). The effect of inorganic fertilizers in combination with various organics (cow dung, green manure (Sesbania aculeata) Azolla compost, rice husk) on CH 4 emission, global warming potential, and soil carbon storage along with crop productivity were studied at university farm under field conditions. The experiment was conducted in a randomized block design for 2 years in a monsoon rice (cv. Ranjit) ecosystem (June-November, 2014 and 2015). Combined application of inorganic (NPK) with Sesbania aculeata resulted in high global warming potential (GWP) of 887.4 kg CO 2 ha -1 and low GWP of 540.6 kg CO 2 ha -1 was recorded from inorganic fertilizer applied field. Irrespective of the type of organic amendments, flag leaf photosynthesis of the rice crop increased over NPK application (control). There was an increase in CH 4 emission from the organic amended fields compared to NPK alone. The combined application of NPK and Azolla compost was effective in the buildup of soil carbon (16.93 g kg -1 ) and capacity of soil carbon storage (28.1 Mg C ha -1 ) with high carbon efficiency ratio (16.9). Azolla compost application along with NPK recorded 15.66% higher CH 4 emission with 27.43% yield increment over control. Azolla compost application significantly enhanced carbon storage of soil and improved the yielding ability of grain (6.55 Mg ha -1 ) over other treatments.

La mortalidad por enfermedades del corazón y por reumatismo en la ciudad de bogotá

OpenAIRE

Bejarano, Jorge

2012-01-01

La alta cifra de mortalidad por enfermedades cardio-vasculares está indicando la urgencia de una campana para contener sus avances. De todas las adquisiciones sanitarias, ninguna ha tenido el alcance y los resultados admirables de los centros o dispensarios destinados al tratamiento de una enfermedad y a la educación del enfermo. Nadie podrá pues, dudar que los dispensarios o consultorios de enfermedades cardio-vasculares, sea una de las armas más eficaces en la lucha contra la mortalidad por...

Levantamiento del proceso de registros contables por causación de las cuentas por cobrar a clientes

OpenAIRE

Mayele-Rodríguez, Luz

2013-01-01

De igual forma el Proyecto de Mejora de Procesos a elaborar, desarrollar e implementar en el Área Administrativa y Financiera del Centro de Pinturas Automotriz “LMS”, es realizar el levantamiento del Proceso de Registros Contables por Causación de las cuentas por cobrar a clientes. Lo anterior se puede desarrollar a partir de un poder de negociación con proveedores que incluye entre otros los siguientes factores : El plazo alcanzado en la negociación de compras de insumos, materias primas, co...

Alarma activada por control remoto selectivo.

OpenAIRE

Eguíluz Morán, Luis Ignacio; Lara Santillán, Pedro María; Mañana Canteli, Mario

1995-01-01

La finalidad de esta invención consiste en disponer de una alarma que bien evite el robo de objetos ligeros y portátiles por el procedimiento que se conoce como "del tirón" --es decir, arrebatar algo y salir corriendo--, bien permita identificar un equipaje entre otros. La originalidad del dispositivo reside en la activación/desactivación del dispositivo de sonido por control remoto, así como la posibilidad de seleccionar el sonido de salida dependiendo de su finalidad. Se reivindica como de ...

San Sebastian, vista por Paret y Alcázar

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María Castilla Albisu

2013-07-01

Full Text Available Luis Paret y Alcázar pintó una serie de vistas panorámicas de puertos del litoral Cantábrico, por encargo del rey Carlos III. El objetivo de este trabajo es ahondar en la vida de este pintor para así comprender mejor su obra. A pesar de los estudios realizados por algunos historiadores quedan todavía incógnitas por descubrir relativas a la vida y al trabajo de este artista. Al acercarse a la figura de Paret y Alcázar hay que preguntarse por qué habiendo sido uno de los pintores más prometedores de su tiempo, su figura ha caído en un triste olvido.

Trisegmentectomia hepática direita por videolaparoscopia

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Marcel Autran C. Machado

Full Text Available INTRODUÇÃO: Em 2007 os autores descreveram a primeira hepatectomia direita por videolaparoscopia realizada no Brasil. Hepatectomia direita ampliada, também conhecida como trisegmentectomia direita, é procedimento altamente complexo e implica em grande retirada do volume hepático. Os autores descrevem a primeira trisegmentectomia direita por videolaparoscopia realizada no Brasil. TÉCNICA: O paciente é colocado em posição supina em decúbito lateral esquerdo. O cirurgião se coloca entre as pernas da paciente. Utilizamos cinco trocartes, três de 12 mm e dois de 5 mm. Devido à embolização prévia da veia porta direita, o hilo hepático não é dissecado. O pedículo portal direito é seccionado com grampeador laparoscópico de carga vascular por meio de acesso intra-hepático, segundo técnica previamente descrita pelos autores. A seguir procede-se a mobilização do fígado direito seguido de dissecção da veia cava retro-hepática e secção da veia hepática direita. Estes passos são realizados sem manobra de Pringle. O fígado é seccionado com combinação de bisturi harmônico e grampeador endoscópico. O pedículo do segmento 4 é seccionado dentro do fígado. O espécime é retirado por meio de incisão supra-púbica e a área cruenta é revista para verificar hemostasia. O procedimento é encerrado e dreno de sistema fechado é posicionado junto à área cruenta. CONCLUSÃO: Trisegmentectomia hepática direita por videolaparoscopia é procedimento factível e seguro e deve ser considerado para pacientes selecionados. Este procedimento deve ser realizado em centros especializados e por cirurgiões com experiência tanto em cirurgia hepática como cirurgia laparoscópica avançada.

Análisis Competitivo por parte de los talleres de servicio automotriz, mediante el uso del valor percibido por el cliente

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Jaime Baby Moreno

2015-06-01

Full Text Available Este artículo trata del uso del Valor Percibido por el Cliente (VPC como herramienta para el análisis competitivo por parte de talleres de reparación y mantenimiento automotriz. Se muestra cómo se determinan tanto la importancia relativa de los atributos que los compradores tienen en cuenta para evaluar el desempeño de un taller automotriz, como la evaluación de desempeño, realizada por los compradores de los "Talleres de los concesionarios" y de aquellos que son propiedad de individuos. Posteriormente, se ilustra la manera como unos y otros visualizan su posición competitiva. También muestra la brecha entre los valores ideales esperados y los percibidos por el mercado, la cual se constituye en una especie de "mapa" de oportunidades para las firmas actualmente presentes en el mercado y para nuevos participantes.

Malnutrición por defecto de un recién nacido por psicosis puerperal materna: presentación de un caso

OpenAIRE

Gavilla González, Bárbara; Díaz Cabrera, Leticia

2011-01-01

En el siguiente trabajo se realizó el seguimiento de un niño desde la etapa de recién nacido hasta el año de edad por malnutrición por defecto, de causa materna por psicosis puerperal. En este caso, la madre rechazaba a su hijo, negándose a alimentarlo, privando al bebé de algo tan importante en esta etapa de la vida como la lactancia materna exclusiva, requiriendo de alimentación complementaria en edad temprana para lograr un aumento de peso adecuado y un desarrollo psicomotor que se igualar...

Malnutrición por defecto de un recién nacido por psicosis puerperal materna: presentación de un caso

OpenAIRE

Gavilla González, Bárbara; Díaz Cabrera, Leticia

2012-01-01

En el siguiente trabajo se realizó el seguimiento de un niño desde la etapa de recién nacido hasta el año de edad, por malnutrición por defecto, de causa materna por psicosis puerperal. En este caso, la madre rechazaba a su hijo, negándose a alimentarlo, privando al bebé de algo tan importante en esta etapa de la vida como la lactancia materna exclusiva, requiriendo de alimentación complementaria en edad temprana para lograr un aumento de peso adecuado y un desarrollo psicomotor que se iguala...

Transmisión de Anaplasma marginale por garrapatas

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Kelly A. Brayton

2012-01-01

Full Text Available Anaplasma marginale, patógeno de distribución mundial, es transmitido por garrapatas Ixódidas. Comprender su complejo desarrollo dentro de la garrapata vector, permitirá la predicción de brotes y ofrecerá oportunidades para controlar su transmisión. En este trabajo se revisa su ciclo básico de desarrollo junto con los estudios recientes acerca de las diferencias de transmisión entre cepas, que delinean aspectos de la interacción patógeno - vector. Bacterias, virus o protozoarios transmitidos por artrópodos causan enfermedades severas, tanto en humanos como en animales. Las enfermedades infecciosas transmitidas por garrapatas, entre las que incluimos a la Anaplasmosis (A. marginale, babesiosis (Babesia bigemina, B. bovis, B. divergens y Theileriosis (Theileria annulata, T. parva, se encuentran entre las más importantes en el ámbito mundial, con pérdidas cercanas a los siete mil millones de dólares anualmente; y, a pesar de su impacto, permanecen escasamente bajo control, basado primordialmente en la aplicación de acaricidas, para interrumpir su transmisión. La aparición de garrapatas resistentes a múltiples sustancias acaricidas, representa una amenaza en este tipo de control y, como resultado, hay un resurgimiento de la investigación para el desarrollo de nuevas estrategias para su control. Nuevas opciones para prevenir la transmisión de patógenos de animales por garrapatas, será el resultado de entender las interacciones garrapata patógeno; proceso que culmina con el desarrollo de la infección y transmisión exitosa. En todos los casos de patógenos transmitidos por garrapatas, el desarrollo de la infección se realiza coordinamente a los momentos de adhesión y alimentación del vector sobre el animal. Esto sucede por la interdependencia en la señalización entre el patógeno y el vector al alimentarse y, por ello, será susceptible de intervención.

Del significado responsabilidad de los socios en las compañías mercantiles por acciones y por cuotas.

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Jorge Payome Suárez

2003-01-01

Full Text Available El comentario presentado, además de constituir una guía útil para los socios de compañías mercantiles por acciones y por cuotas, en un aspecto de indudable importancia para ellos, cual es el de su eventual responsabilidad, se erige como una herramienta provechosa para estudiantes y profesionales interesados en el tema. La experiencia académica y docente del autor del ensayo aseguran un análisis autorizado de la materia.

Consumo Voluntario de Forraje por Rumiantes en Pastoreo Consumo Voluntario de Forraje por Rumiantes en Pastoreo

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José Mejía Haro

2012-02-01

Full Text Available The variation in voluntary forage intake is undoubtedly the major dietary factor determining level and efficiency of ruminant production. This variation is bigger and least predictable for grazing ruminants. Range ruminant productivity and efficiency is relatively low due, partly, to intake limitations; productivity could probably be increased most by increasing intake. Distension of the reticulo-rumen wall is the primary intake regulation mechanism of low-quality roughages in range ruminants, digestibility and rate of ingest passage also affect voluntary intake. Body size and metabolic bodysize as well affect intake of grazing animals. Kind and amount of supplementation, forage availability, and grazing intensity have been related to voluntary forage intake. La variación en el consumo voluntario de forraje es indudablemente el principal factor dietario que determina el nivel y eficiencia de producción en un rumiante. Esta variación es mayor y muy difícil de predecir bajo condiciones de pastoreo. La productividad y eficiencia de rumiantes en pastoreo es relativamente baja debido, en parte, a las limitaciones en el consumo; la productividad probablemente se podrá incrementar si se incrementa el consumo. La distensión de la pared del rumenretículo es el principal mecanismo de regulación del consumo de forrajes de baja calidad en rumiantes en pastoreo, aunque la digestibilidad y la tasa de pasaje también afectan el consumo voluntario. Igualmente, el consumo se ve afectado por el tamaño corporal y peso metabólico del animal, por la cantidad y tipo de suplemento ofrecido, por la disponibilidad de forraje y por la intensidad del pastoreo.

Evaluación del riesgo ambiental por metales pesados, generados por la actividad minera artesanal en los ríos Quiroz y Chira – Piura por el método de especiación secuencial

OpenAIRE

Loaiza Choque, Leonardo Edwin

2016-01-01

Determina el riesgo ambiental que representan los metales pesados dispuestos en los sedimentos de los ríos Quiroz y Chira ubicados en el departamento de Piura generados por la minería artesanal. Determina las formas químicas en las que se dispersan los metales pesados ambos ríos. Demuestra que el estudio por extracción secuencial puede ser usado como componente de herramienta de gestión ambiental. Realiza el análisis de extracción secuencial por el método BCR el mismo que permite determinar l...

Retinitis por citomegalovirus en un paciente con VIH

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Alena de los Ángeles Vejerano Duany

Full Text Available La retinitis por citomegalovirus es la infección ocular más frecuente en pacientes con un recuento de linfocitos CD4 inferior a 200 por µL. El aspecto oftalmoscópico de las lesiones se caracteriza, en la mayoría de los casos, por infiltrados retinianos resultados de la necrosis retiniana producida por citomegalovirus y el edema en asociación con hemorragias. Estas lesiones se disponen, por lo general, siguiendo las arcadas vasculares temporales con invasión hacia la mácula. Se presentó una paciente de 24 años de edad, femenina, blanca, ama de casa, con antecedentes patológicos personales oculares sin datos de interés, y antecedentes patológicos personales generales de ser diagnosticadas con VIH. Hace cuatro años que comenzó con tratamiento antirretroviral, y tuvo cambios de tratamiento en dos ocasiones. El último fue impuesto en mayo del año 2011, con el cual presentó mala adherencia terapéutica, y comenzó desde entonces a presentar disminución de su peso corporal de forma marcada en breve período de tiempo. Refiere que desde hace unos meses comenzó a presentar una disminución progresiva de la agudeza visual en el ojo derecho, acompañado de visión borrosa. Adquiere gran importancia este caso, ya que ante la supervivencia de los pacientes con sida, va a ser cada vez más frecuente la aparición de las afecciones oculares relacionadas con esta enfermedad. Dentro de ellas se encuentran las infecciones oportunistas mayores como la retinitis por citomegalovirus.

Diferenciales salariales por género y región en Colombia: Una aproximación con regresión por cuantiles

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Luis Armando Galvis

2010-12-01

Full Text Available La existencia de brechas salariales por género es un fenómeno que, al igual que en muchos otros países, está presente en el mercado laboral colombiano.Esas brechas no son homogéneas en todo el territorio, lo que justifica un análisis detallado de lo que ocurre en cada una de las regiones del país. Los resultados muestran diferenciales de salarios positivos en favor de los hombres en la mayoría de las ciudades principales. Sin embargo, no todo este fenómeno puede ser atribuido a la existencia de discriminación, por cuanto existen variados factores que explican parte de la brecha salarial. Para identificarlos se emplea la descomposición de Blinder-Oaxaca (BO en el contexto de regresión por cuantiles. Los resultadosde la aplicación de esta metodología sugieren que las brechas salariales no están explicadas por los atributos observables de los individuos. Dichas disparidades son en su mayoría explicadas por el efecto de las diferencias en la remuneración de atributos tales como la educación, además de elementos no observados. Por ciudades,el estudio muestra patrones que revelan una mayor brecha salarial en las regiones periféricas en comparación con Bogotá, Cali, Medellín, Manizales y Pereira.Dado que el efecto remuneración comprende, entre otros, la posible existencia de discriminación por género, es importante que se le otorgue la debida atención a este resultado para efectos de formular políticas en este sentido.

Mortalidad por meningitis por Pasteurella canis. Oportunidades de aprendizaje

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Ana Rosa Ropero Vera

2016-01-01

Full Text Available La meningitis bacteriana es una enfermedad importante de distribución mundial, causa mayor y sustancial de mortalidad y morbilidad en países en desarrollo. La Organización Mundial de la Salud (OMS sostiene que la meningitis es una de las diez afecciones principales del ser humano y debe ser considerada como una emergencia infectológica; por eso es fundamental reconocer que esta enfermedad es causa de muerte en niños de todo el mundo, sin distinción de raza, nivel económico o sociocultural. Se realizó una investigación de caso en menor de 53 días de nacido, que cumplía con los criterios clínicos y de laboratorio compatible con meningitis bacteriana, con el propósito de analizar y fortalecer la toma de decisiones en salud pública por parte de la secretaría local de salud del municipio de Valledupar (Colombia. Entre los hallazgos se encontró antecedentes infecciosos en el menor, coloración de Gram y cultivo de LCR, en el que se identificó cocobacilos Gram negativos, que fueron aislados como agente causal Pasteurella canis. Este estudio pretende sensibilizar a los prestadores de salud para que cuenten con personal altamente capacitado para brindar tratamientos adecuados y prevenir complicaciones en la meningitis bacteriana en niños, y así disminuir la posibilidad de secuelas o muerte, tanto en pacientes con compromiso inmunológico o sin este.

Por un humor ético

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Victor Paramo Valero

2016-04-01

Full Text Available Ética del humor es una obra original, abundantemente documentada, de contenido científico y filosófico, que aborda un problema de gran importancia en los actuales estudios de éticas aplicadas. La ética del humor es una nueva ética aplicada que pretende comprender el fenómeno del humor a la luz de sus implicaciones éticas. Como señala el autor, Juan Carlos Siurana, reputado experto en el ámbito de la filosofía práctica, el interés por el humor es un interés por la ética. En la obra no presenta una nueva teoría filosófica del humor –las cuales se han venido sucediendo, al menos, desde los Diálogos de Platón–, sino una nueva teoría ética, que toma al humor como objeto principal de análisis. Por tanto, la finalidad es realizar una aportación dentro del ámbito de la ética. Para ello se nutre de distintos estudios psicológicos, biológicos, fisiológicos y neurológicos sobre el humor, así como de clásicas obras de filosofía que han abordado esta cuestión.

Escolhas Associadas ao Automóvel por Homens e por Mulheres: confluência ou divergência? Choices associated with automobiles for Men and Women: convergence or divergence? Opciones relacionadas con el Automóvil por Hombres y por Mujeres: ¿convergencia o divergencia?

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LICHT, René Henrique Götz

2009-03-01

Full Text Available RESUMOO aumento do poder de compra das mulheres tem levado empresas a adotarem estratégias de diferenciação de produtos e a produzirem produtos específicos para o público feminino. A indústria automobilística não está imune a este fenômeno, uma vez que as mulheres representam aproximadamente metade das vendas de automóvel no país. Considerando as diferenças de consumo e de comportamento entre mulheres e homens é colocada a seguinte questão: há diferenças entre escolhas associadas ao automóvel por homens e mulheres? Foram apresentados aos participantes itens presentes no dia-a-dia das pessoas, e que são por elas valorizados; e foi solicitado aos participantes que escolhessem e associassem estes itens ao automóvel. A análise dos resultados revelou haver mais semelhanças do que diferenças entre escolhas associadas ao automóvel por homens e escolhas associadas ao automóvel por mulheres. A semelhança entre as escolhas sugere que as representações, os significados e valores atribuídos ao automóvel por homens e por mulheres são similares e, desta forma, a estratégia de diferenciação de produtos não se aplica à indústria automobilística.ABSTRACTThe increase of the women purchase power has led some companies to adopt strategies of products differentiation as well as to produce specific products to the female public. The auto industry is not immune to this phenomenon, once the women represent, approximately, half of the automobile sales in the country. Considering the consumption and the behavior differences between women and men, it has set the following question: are there differences between the choices associated to the automobile by men and the choices associated to the automobile by women? It has been presented to the participants items found in the people’s day-by-day, which are valorized by them, and the participants have been asked to choose and associate these items to the automobile. The results analysis

Acuerdo por la discreción

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Yeny Serrano

2006-01-01

Full Text Available En este artículo se propone un análisis del texto del Acuerdo por la discreción firmado en 1999 por 32 directores de medios de comunicación para “elevar el nivel de calidad y responsabilidad en el cubrimiento y difusión de hechos violentos”. Se analizan los factores que impiden que este Acuerdo produzca cambios efectivos en la práctica profesional informativa y se presenta un modelo (Lemieux, 2000 que tiene en cuenta las variables que influyen en la producción del discurso informativo mediático.

Clonación humana: las preguntas «por qué no» y «por qué sí»

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Velayos Castelo, Carmen

2002-12-01

Full Text Available Why not cloning us is a relevant question for contemporary ethics. The question why not, when it refers to a technology (or to some of its applications, is the question for its moral limits. In other words, it is the question for the universal dangers that a technology entails or could entail in some of its applications. The sphere of the moral evaluation of a technology has to do with the public elimination of the possible harms that are inherent or supervenient to its utilisation. If we focus on the relevant normative questions of the justice sphere, it couldn´t be relevant to answer the question why, that is, why a person or a group of them would wish the technology was applied The question why is related to vital options and ways of create ourselves that needn´t be binding on someone nor are characteristic of the moral point of view. However, the suspicion of this article is the following: the specific character of contemporary technological innovation (of which cloning is a paradigmatic case stimulates and makes relevant the debate about the good (given the collective or global implications of the answers.

Por qué no clonarnos es una pregunta relevante para la ética actual. El por qué no de una técnica -o de determinadas aplicaciones de la misma- es la pregunta por los límites morales. O, de otro modo, es la pregunta por los daños objetivos que ésta supone, o supondría en una determinada aplicación. El marco de evaluación moral de una técnica tiene que ver, pues, con la desestimación pública y universal de posibles daños inherentes o sobrevenibles a su uso. Circunscritas las cuestiones normativas relevantes al ámbito de la justicia, no parecería relevante clarificar cuál sea el por qué -o el por qué sí- un individuo o un conjunto de ellos buscarían la aplicación o puesta en marcha de una técnica. Ésta es la pregunta por opciones vitales y

Lower Mississippi River Environmental Program. Report 11. Forest Vegetation of the Leveed Floodplain of the Lower Mississippi River

Science.gov (United States)

1988-02-01

styraciflua, Fraxinus pennsylvanica, Carya illinoensis and Quercus CC .-. sp. may occur but are rare and were not sampled in this study. 88. The subtype... illinoensis (Wang.) K. Koch Carya laciniosa (Michaux f.) Loudon Juglans nigra L. BETULACEAE Carpinus caroliniana Walter Ostrya virginiana (Miller) K. Koch...between Baton Rouge and Memphis include Quercus nuttallii and Ulmus crassifolia. Acer saccharinum, Carya cordiformis, Carya laciniosa, and Juglans nigra

How Does Temperature Impact Leaf Size and Shape in Four Woody Dicot Species? Testing the Assumptions of Leaf Physiognomy-Climate Models

Science.gov (United States)

McKee, M.; Royer, D. L.

2017-12-01

The physiognomy (size and shape) of fossilized leaves has been used to reconstruct the mean annual temperature of ancient environments. Colder temperatures often select for larger and more abundant leaf teeth—serrated edges on leaf margins—as well as a greater degree of leaf dissection. However, to be able to accurately predict paleotemperature from the morphology of fossilized leaves, leaves must be able to react quickly and in a predictable manner to changes in temperature. We examined the extent to which temperature affects leaf morphology in four tree species: Carpinus caroliniana, Acer negundo, Ilex opaca, and Ostrya virginiana. Saplings of these species were grown in two growth cabinets under contrasting temperatures (17 and 25 °C). Compared to the cool treatment, in the warm treatment Carpinus caroliniana leaves had significantly fewer leaf teeth and a lower ratio of total number of leaf teeth to internal perimeter; and Acer negundo leaves had a significantly lower feret diameter ratio (a measure of leaf dissection). In addition, a two-way ANOVA tested the influence of temperature and species on leaf physiognomy. This analysis revealed that all plants, regardless of species, tended to develop more highly dissected leaves with more leaf teeth in the cool treatment. Because the cabinets maintained equivalent moisture, humidity, and CO2 concentration between the two treatments, these results demonstrate that these species could rapidly adapt to changes in temperature. However, not all of the species reacted identically to temperature changes. For example, Acer negundo, Carpinus caroliniana, and Ostrya virginiana all had a higher number of total teeth in the cool treatment compared to the warm treatment, but the opposite was true for Ilex opaca. Our work questions a fundamental assumption common to all models predicting paleotemperature from the physiognomy of fossilized leaves: a given climate will inevitably select for the same leaf physiognomy

Orlando Castellanos. La pasión por la radio

OpenAIRE

Castellanos Molina, Orlando, 1930-1998

2004-01-01

Documento sonoro en el que se recogen entrevistas realizadas a Orlando Castellanos por Miguel Ángel de la Guardia, Miladys Ochoa, Fernando Rodríguez Sánchez (Ciego de Ávila), Ángel Ferrera, Boshmonar, Jaime Almiral, Radio Umbral de Santiago de Chile, Franco Carbón, Luis Toledo Sande y Estrella Díaz. Esta grabación pertenece a la colección Palabra Viva, desarrollada por el Centro Cultural Pablo de la Torriente Brau, a partir de las entrevistas realizadas por el periodista Orlando Castellanos. ...

MIASIS CUTÁNEA POR CORDYLOBIA ANTHROPOPHAGA

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Miriam Alkorta Gurrutxaga

2001-01-01

Full Text Available El incremento progresivo en el número de personas que viajan a países tropicales ha hecho que las enfermedades importadas adquieran una relevancia cada vez mayor. Las miasis (o infestaciones por larvas de moscas cutáneas se encuentran entre este tipo de enfermedades siendo especialmente frecuentes en países tropicales. A propósito de la observación de un caso de miasis cutánea masiva por Cordylobia antropophaga, que ocurrió en una mujer de 34 años de edad al volver de un viaje a Senegal, se ha efectuado una revisión de los casos de miasis cutáneas forunculoides importadas publicados en España, así como de la biología, patología, tratamiento y prevención de la miasis humana por Cordylobia anthropophaga. El caso referido, se caracterizó por la infestación con un número inusualmente elevado de larvas, no sospechándose su etiología hasta la fase final de la enfermedad. La emergencia continuada de larvas (se recogieron 91 generó en la paciente un estado de ansiedad importante. Finalmente, la eliminación de las larvas provocó una rápida mejoría de la paciente. Aunque los casos de miasis cutánea no tienen la gravedad de otras enfermedades importadas, su conocimiento es necesario desde el punto de vista preventivo, diagnóstico y terapeútico. Es importante proceder a la identificación morfológica de las larvas diferenciándolas de otro tipo de miasis con implicaciones terapéuticas diferentes.

Mortalidade por leucemias relacionada à industrialização

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Leal Carmen Helena Seoane

2002-01-01

Full Text Available OBJETIVO: Analisar a distribuição espacial da mortalidade por leucemia na população, buscando identificar agregados e estabelecer sua relação com os níveis de industrialização. MÉTODOS: O estudo foi realizado nas 43 regiões de governo do Estado de São Paulo, no qüinqüênio 1991-1995. Foi construído um "índice de industrialização relativo à leucemia" (IIRL baseado no número de indústrias e empregos industriais por 100.000 habitantes, valor adicionado fiscal, variedade de ramos industriais e indústrias com potenciais exposições de risco para a leucemia. O IIRL foi distribuído em cinco categorias. Verificaram-se os coeficientes padronizados de mortalidade por leucemia em cada uma das regiões, também distribuídos em cinco categorias e comparados ao mapa IIRL. RESULTADOS: As regiões mais industrializadas em ordem decrescente foram Campinas, Piracicaba, Jundiaí, Sorocaba e São Paulo. Não foi encontrada associação entre mortalidade, por nenhum tipo de leucemia, e industrialização. A região de Jales foi a que apresentou o mais alto coeficiente padronizado de mortalidade por leucemia. CONCLUSÕES: A distribuição da mortalidade por leucemia ocorreu de forma homogênea no Estado de São Paulo, não apresentando correlação com o nível de industrialização. Entretanto, aspectos relacionados ao método epidemiológico adotado -- estudo ecológico -- e ao uso do parâmetro "mortalidade por leucemia", doença cujo prognóstico tem mudado muito nas últimas décadas, limitaram a interpretação dos resultados.

Perspectivas mecanisticas de reações organicas catalisadas por paladio : Heck, oxa-Heck e acoplamento de Buchwald-Hartwig por ESI-MS/MS

OpenAIRE

Boniek Gontijo Vaz

2009-01-01

Resumo: A espectrometria de Massas por eletronspray (ESI-MS) tornou-se um método prático para o estudo de mecanismos reacionais em solução. Neste trabalho importantes reações catalisadas por paládio: reação de Heck-Mizoroki, oxa-Heck e o acoplamento de Buchwald-Hartwig foram monitoradas por ESI-MS visando interceptar espécies que comprovam as atuais propostas mecanísticas ou que abram caminho para novas propostas para estas reações. O monitoramento das reações foi realizado no modo off-line, ...

DE ACUMULACIÓN POR DESPOSESIÓN

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Sebastián Gómez Lende

2015-01-01

Full Text Available Omnipresente, la acumulación por desposesión es uno de los elementos centrales del orden global contemporáneo. Observados desde una perspectiva crítica, los usos extractivos del territorio constituyen una de las principales expresiones de ese proceso. A la luz de ese sistema de ideas, este artículo procura demostrar que el modelo sojero actualmente vigente en la Argentina es una de las formas más completas, exhaustivas, actuales y sofisticadas, de acumulación por desposesión en el país. En ese sentido, el artículo analiza el boom de la soja transgénica y sus vínculos con las formas tanto seculares (endeudamiento financiero, concentración de la propiedad rural, usurpación de la tierra y actuales de desposesión (degradación de la naturaleza, despojo del derecho a la salud, pillaje de recursos genéticos efectuadas por los grandes agricultores, el capital financiero, las agroindustrias y las corporaciones biotecnológicas, en detrimento de los pequeños productores, los campesinos, los pueblos aborígenes y la población en general.

La compra por impulso de productos de alimentación

DEFF Research Database (Denmark)

Luna-Arocas, Roberto; Bech-Larsen, Tino

2004-01-01

El consumo de productos de alimentación muestra una serie de matices diferenciales en su análisis si lo comparamos con otros productos de compra por impulso. En este sentido, se relaciona la compra por impulso de productos de alimentación con una baja importancia de la imagen fisica, y con las de...... descrepancias personales entre lo que un individuo es y quiere ser. Como resultado en una mestra de estudisantes, la compra por impulso de productes de alimentación se relaciona con imagen fisica pero no con las discrepanacias personales.......El consumo de productos de alimentación muestra una serie de matices diferenciales en su análisis si lo comparamos con otros productos de compra por impulso. En este sentido, se relaciona la compra por impulso de productos de alimentación con una baja importancia de la imagen fisica, y con las...

Itinerarios didácticos por la isla de Tenerife

OpenAIRE

Becerra Ramírez, María Carmen; Javier Dóniz-Páez; González Cárdenas, Elena; Gosálvez, Rafael U.; Becerra-Ramírez, Rafael; Escobar Lahoz, Estela

2013-01-01

Con la elaboración de esta guía de Itinerarios Didácticos por la isla de Tenerife pretendemos contribuir a un mayor conocimiento de las características geográficas de un espacio dominado por las formas y formaciones volcánicas que caracterizan un paisaje fuertemente modificado por la actividad humana. El hombre convive y usa lo que los volcanes le ofrecen, tradicionalmente como soporte de sus cultivos o de su actividad ganadera,y modernamente como base de la industria turística. Los itiner...

¿Por qué estudiar en la Universidad EAN?

OpenAIRE

2013-01-01

Razones para estudiar en la Universidad EAN: 1. Por ser la Universidad No.1 en Latinoamérica y No. 28 en el mundo, según el ranking mundial de Escuelas de Negocios que lidera el Consejo Superior de Investigaciones Científicas – Laboratorio de Cibermetría de España. 2. Por la flexibilidad en los planes de estudio que permite adelantar unidades y cursar la carrera en un tiempo menor. 3. Por la formación académica en dos ciclos semestrales, favoreciendo el aprendizaje y la concentrac...

"Efecto del ingreso obtenido por el socio industrial por concepto de alimentos en la sociedad en nombre colectivo"

OpenAIRE

Adame Alba, Nayzeth

2011-01-01

Hoy en día la excesiva carga tributaria en nuestro país, nos obliga a buscar alternativas factibles y seguras, en el cumplimiento de las obligaciones fiscales, por ello, debemos aprovechar la existencia de figuras jurídicas útiles para la optimización de recursos financieros dentro del marco de ley, es el caso de la sociedad en nombre colectivo, que nos permite la existencia de socios industriales que a su vez, el ingreso que perciben por concepto de alimentos se encuentra exento de impuestos...

PENGARUH PEMBERIAN TUMBUHAN AIR PADA AIR LIMBAH RUMAH TANGGA TERHADAP PERTUMBUHAN IKAN GURAMI (Osphronemus gouramy SEBAGAI INFORMASI BAGI MASYARAKAT TENTANG PENCEMARAN LINGKUNGAN DAN DAUR ULANG LIMBAH

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Hafzon Exaputra

2016-05-01

Full Text Available Utilization fern (Azolla pinnata and water hyacinth (Eichhornia crassipes in addition to preserving the environment also produces elements that are needed for the growth of living things. Household wastewater by plants Azolla pinnata and hyacinth will return sustainability, and can be used as a maintenance gourami (Osphronemus gouramy.        The purpose of this research are: (1 to determine the effect of aquatic plants in domestic wastewater to the quality of the water quality standard household waste and growth of carp (Osphronemus gouramy. (2 to find out which one is better growth of carp (Osphronemus gouramy in household waste water between the new and old by fern (Azolla pinnata and by plants hyacinth (Eichhornia crassipes. (3 as a source of information for the public about environmental pollution and recycling of waste water by using plants in domestic wastewater.        This type of research experiments. Samples of each treatment 20 fish carp with 4 treatments. Treatment I (wastewater new households by ferns, treatment of II (wastewater new households by plants hyacinth, Treatment III (domestic wastewater long by ferns, treatment IV (household wastewater long by water hyacinth plants. The measured parameters ie width, length and weight of carp within a certain period. Data were analyzed using Analysis of Variance (ANOVA two lanes and qualitative analysis.        The results obtained by analysis of existing water plants on the effect of domestic wastewater on growth of carp (Osphronemus gouramy, as well as the provision of fern (Azolla pinnata provides the most good influence on the growth of carp. Kata Kunci: Tumbuhan air, air limbah rumah tangga, pertumbuhan ikan gurami.

ANTIOXIDANTES: MICRONUTRIENTES EN LUCHA POR LA SALUD

OpenAIRE

Zamora S, Juan Diego

2007-01-01

Los antioxidantes son sustancias químicas que se caracterizan por impedir o retrasar la oxidación de diversas sustancias principalmente de los ácidos grasos cuyas reacciones se producen tanto en los alimentos como en el organismo humano, en el cual puede provocar alteraciones fisiológicas importantes desencadenantes de diversas enfermedades. Otra de las funciones de los antioxidantes es facilitar el uso fisiológico del oxígeno por parte de las mitocondrias celulares, ayudando a reducir los ef...

Esporotricosis diagnosticada por el laboratorio

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Nelly Ordóñez

1989-06-01

Full Text Available De 1976 a 1989 se han diagnosticado 40 casos de esporotricosis en el laboratorio de Micología del Instituto Nacional de Salud. La enfermedad se presentó en pacientes entre 4 y 52 años y tuvo predilección por el sexo masculino: 35 de 40 (87,5%; las formas clínicas más frecuentes fueron la cutánea fija, 18 de 40 (45%, y la linfocutánea, 17 de 40 (42,5%, con localización mayor en miembros superiores, 18 de 40 (45%. El diagnóstico se estableció por el aislamiento del Sporothrix schenckii en 35 de 38 pacientes (92%; los otros dos pacientes se diagnosticaron empleando otras técnicas: inmunofluorescencia directa, intradermorreacción y aglutinación en tubo.

Análise Sazonal das Regiões do Rio Grande do Sul Atingidas por Eventos Severos Gerados por SCM no Período de 2004 a 2008

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Gustavo Rasera

2012-07-01

Full Text Available ntos Severos (ES, como por exemplo, vendaval, granizo e enchente, têm sido estudados com frequência devido à gravidade dos danos que estes causam à sociedade. Um dos sistemas meteorológicos que é bastante comum no Rio Grande do Sul (RS, e que frequentemente está associado aos ES são os Sistemas Convectivos de Mesoescala (SCM. Como a economia do RS é voltada majoritariamente para a agricultura, que é bastante suscetível às mudanças do tempo, é frequente no Estado a ocorrência de prejuízos econômicos causados por ES. Diante disso, o objetivo deste trabalho foi analisar a distribuição sazonal das regiões atingidas por ES gerados por SCM que afetaram o RS (ESSCMRS no período de 2004 a 2008. Foram utilizados, para o período de estudo, dados de ocorrências de ES e municípios atingidos por ES (MAES obtidos no banco de dados da Coordenadoria Estadual de Defesa Civil do RS; trajetórias dos SCM que afetaram o RS (SCMRS geradas a partir de informações fornecidas pela ferramenta ForTrACC (Forecasting and Tracking of Active Cloud Clusters e imagens brutas do satélite GOES 10 e 12 do canal 4. Os resultados obtidos mostraram que: i ~45% dos ES observados foram gerados por SCMRS; ii ~58% dos MAES foram atingidos por SCMRS; iii a porção norte do RS foi a mais atingida por ESSCMRS; iv vendaval e granizo foram os tipos de ESSCMRS que atingiram o maior número de municípios e v JAS (jul-ago-set foi o trimestre que apresentou o maior número de municípios atingidos por ESSCMRS (MAES-SCMRS.

El aprendizaje visto por los estudiantes venezolanos

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Berta Elena Barrios

2015-01-01

Full Text Available En el siguiente trabajo se presentan los resultados de un estudio sobre las con-cepciones del aprendizaje de un grupo de estudiantes venezolanos de educa-ción primaria y media. Se trató de replicar el instrumento y procedimiento deanálisis utilizado por los investigadores Berry y Sahlberg (1996, con el objetivode caracterizar cómo conciben el aprendizaje estudiantes venezolanos entre 11y 15 años de edad y compararlo con sus pares ingleses y finlandeses. El análi-sis de resultados se basó en los criterios propuestos por dichos autores, deno-minados Pasos para un Buen Aprendizaje. Los hallazgos indican que los estu-diantes venezolanos conciben el aprendizaje como memorizar conocimientos,básicamente escolares, enseñados por los docentes. Las concepciones deambas poblaciones se ubican en una visión pasiva del aprendizaje. Se discutela vinculación de las concepciones del aprendizaje con las prácticas de la escuela.

Epidemiologia das infecções hematogênicas por Candida spp

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Colombo Arnaldo Lopes

2003-01-01

Full Text Available O gênero Candida spp é responsável por cerca de 80% das infecções fúngicas no ambiente hospitalar e constitui causa relevante de infecções de corrente sanguínea. Nos Estados Unidos da América, Candida spp é a quarta causa mais comum de infecções de corrente sanguínea, respondendo por cerca de 8% dos casos das infecções documentadas neste sítio. Espécies não-albicans respondem hoje por ao menos 50% das infecções invasivas por Candida spp, apresentando peculiaridades de história natural e sensibilidade a antifúngicos. A mortalidade geral de fungemias por Candida spp é da ordem de 40 a 60%, tornado esta complicação infecciosa um grande desafio para os clínicos que trabalham em hospitais terciários em diferentes países.

Neumonitis por hipersensibilidad en la ciudad de México

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Carrillo-Rodríguez José G.

2000-01-01

Full Text Available OBJETIVO: Determinar la asociación entre la zona urbana de origen del paciente en la ciudad de México y la prevalencia de neumonitis por hipersensibilidad inducida por antígeno aviario. MATERIAL Y MÉTODOS: Se trata de un estudio de casos y controles realizado en el Instituto Nacional de Enfermedades Respiratorias, en la ciudad de México, en el año de 1999. Se estudiaron 109 casos con neumonitis por hipersensibilidad y 184 controles: de éstos, 39, con fibrosis pulmonar idiopática; 63, con tuberculosis pulmonar, y 82, con asma. La ciudad de México y las zonas conurbadas se dividieron en cinco zonas geográficas: centro, noreste, sureste, noroeste y el suroeste. Se calcularon las prevalencias de las diferentes enfermedades por zona urbana de los pacientes que participaron en el estudio; como medida de asociación, se estimó la razón de momios, con un intervalo de confianza al 95%. Asimismo, se realizó regresión logística múltiple ajustando por edad, sexo y estrato socioeconómico. RESULTADOS: Ochenta casos de neumonitis por hipersensibilidad se concentraron en el sur del noreste de las zonas conurbadas y la parte norte del sureste de la ciudad de México, 48 y 32, respectivamente (RM= 3.86, IC 95% 2.17-6.96. Treinta y seis controles de asma se localizaron en el suroeste de la ciudad de México, zona donde se ubica el Intituto Nacional de Enfermedades Respiratorias (p<0.05 y cuatro en la zona conurbada. Los controles de tuberculosis pulmonar y fibrosis pulmonar idiopática estuvieron dispersos en la ciudad de México y en las zonas conurbadas. CONCLUSIONES: La zona sur del noreste y el norte de la sureste están asociadas a la neumonitis por hipersensibilidad. Las causas de esta asociación no parece ser geográfica, pero existe el antecedente de que esa zona fue basurero de la ciudad, por lo que partículas orgánicas en el ambiente pudieran coadyuvar a la aparición de esta enfermedad.

PANORAMA LATINOAMERICANO DEL PAGO POR SERVICIOS AMBIENTALES

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González T. Ángela

2008-07-01

Full Text Available Este documento busca proveer al lector de algunos elementos para el análisis y reflexión en torno al pago por servicios ambientales. Para ello, en primera instancia, aborda algunos conceptos básicos relacionados con economía ambiental, seguido de temas como la valoración económica de servicios ambientales y la implementación de mecanismos de pago por algunos de ellos. Lo anterior esta enriquecido con experiencias o estudios de caso a nivel latinoamericano y colombiano.

Efeito protetor da melatonina sobre intoxicações por herbicidas

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Lécio L. de Almeida

2016-03-01

Full Text Available Resumo: O uso inadequado de herbicidas pode resultar em intoxicações agudas e, às vezes, crônicas por exposição em longo prazo a baixos níveis desses agentes tóxicos, podendo o herbicida atuar também como agentes teratogênicos, mutagênicos, cancerígenos e desreguladores endócrinos, com o aparecimento de doenças neurodegenerativas e distúrbios reprodutivos. Estudos têm revelado que a melatonina tem propriedades antioxidantes, anti-inflamatórias e imunomoduladoras e atua na reprodução. Essa indolamina está entre os agentes que têm se mostrado benéfico em intoxicações por herbicidas, porém não há relatos do uso de melatonina contra intoxicações por Glifosato-Roundup®, muito menos em associação com o Paraquat. Dessa forma, o maior interesse no tratamento das intoxicações por herbicidas, tem-se concentrado em medidas que impeçam ou minimizem as lesões celulares provocadas nos diversos sistemas biológicos. Assim, a melatonina, como antioxidante conhecido, pode ser mais uma alternativa contra as intoxicações por herbicidas associados e/ou individuais.

Eficacia del Albendazol en dosis única sobre las infecciones por helmintos transmitidos por el suelo en escolares de una comunidad de Iquitos, Perú

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Theresa W Gyorkos

Full Text Available Objetivos. Determinar la eficacia en dosis única del albendazol sobre las infecciones por helmintos transmitidos por el suelo (HTS en escolares de una comunidad de la ciudad de Iquitos en Perú. Materiales y métodos. Dentro del contexto de un ensayo controlado aleatorizado realizado en una comunidad periurbana de escasos recursos, situada en Iquitos, en la Amazonía de Perú, se obtuvieron muestras de heces de escolares del quinto grado de primaria en 18 escuelas y se analizó la prevalencia y la intensidad de HTS. Un total de 1193 escolares fueron desparasitados con albendazol en dosis única (400 mg. De los 909 escolares que fueron encontrados positivos con al menos una infección por HTS, una muestra aleatoria de 385 fue seguida dos semanas más tarde, cuando se recolectó y analizó una segunda muestra de heces. Resultados. La eficacia del albendazol fue satisfactoria para las infecciones por Ascaris lumbricoides con una tasa de reducción de huevos (TRH de 99,8%; IC 95: 99,3-100 y por anquilostomideos con una TRH de 93,6%, IC 95%: 88,2-96,6 y por Trichuris trichiura con una TRH de 72,7%, IC 95: 58,5-79,1. Conclusiones. Estos resultados son indicativos de niveles satisfactorios de eficacia y son congruentes con datos publicados sobre la eficacia del albendazol y directivas de la Organización Mundial de la Salud. Futuras investigaciones deben centrarse en mejorar la eficacia de las estrategias de tratamiento para la infección por Trichuris trichiura.

ENSAYOS DE CREEP POR TORSIÓN Y TRACCIÓN

OpenAIRE

Daniela Alessio; Sandra Robles; Lilian Moro; René Molina

2017-01-01

En este estudio se efectúa el análisis de dos metodologías de ensayo para evaluar el comportamiento de un material al creep o fluencia por activación térmica o termofluencia. Se realizaron en laboratorio dos tipos de ensayos, por torsión y por tracción, bajo combinaciones de temperatura y tensión comparables, de un acero austenítico, de uso habitual en los equipos de la industria petroquímica de la región. Con los registros adquiridos, se graficaron las diferentes curvas deformación-tiempo de...

Helechos y licofitos de la Reserva Natural Educativa Colonia Benítez (Chaco, Argentina

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Bruno Dematteis

2015-01-01

Full Text Available La Reserva Natural Educativa Colonia Benítez cuenta con una superficie aproximada de ocho ha, está ubicada en el departamento Primero de Mayo, en la provincia del Chaco, Argentina. Desde el punto de vista fitogeográfico, esta área protegida se localiza dentro del Distrito Chaqueño Oriental de la Provincia Chaqueña. Como objetivos de este trabajo se planteó realizar un inventario de helechos y licofitos y una clave para el reconocimiento de los taxa que crecen en esta reserva. A tal fin, se examinaron las colecciones depositadas en CTES, y se realizaron nuevas recolecciones de especímenes. Se registraron 12 géneros con un total de 17 especies, siendo Doryopteris el género mejor representado con tres especies: D. concolor, D. lorentzii y D. pentagona. El género Adiantopsis presentó dos especies (A. chlorophylla y A. tweediana, al igual que Anemia con (A. simplicior y A. tomentosa var. anthriscifolia y Pteris (Pteris denticulata var. tristicula y Pteris vittata. Los demás géneros presentaron sólo una especie: Adiantum lorentzii, Anogramma chaerophylla, Azolla cristata, Hemionitis tomentosa, Microgramma vaccinifolia, Pityrogramma calomelanos var. calomelanos, Pleopeltis minima y Selaginella sellowii. El hábito terrícola fue el mejor representado con 12 especies, de las cuales una de ellas es rupícola y otras tres se pueden comportar como epífitos facultativos, en tanto que los estrictamente epífitos fueron representados por sólo dos especies. Azolla cristata fue la única especie acuática presente. Se presentan observaciones ecológicas y un análisis biogeográfico de las especies registradas

Premian record transmision de datos a 5,44 gigabits por segundo

CERN Multimedia

2003-01-01

"El Laboratorio Europeo para la Fisica de Particulas (CERN) y el Instituto de Tecnologia de California (EEUU) seran galardonados con un premio por haber conseguido batir el record de velocidad de transmision por Internet a 5,44 gigabits por segundo, informaron hoy, miercoles, fuentes de ambos organismos" (1/2 page).

Multiple mechanisms of phase variation of PorA in Neisseria meningitidis

NARCIS (Netherlands)

van der Ende, A.; Hopman, C. T.; Dankert, J.

2000-01-01

Previously, we reported that PorA expression in Neisseria meningitidis is modulated by variation in the length of the homopolymeric tract of guanidine residues between the -35 and -10 regions of the promoter or by deletion of porA. To reveal additional mechanisms of variation in PorA expression, the

Uranium removal from water by five aquatic plants

International Nuclear Information System (INIS)

Hu Nan; Ding Dexin; Li Guangyue; Wang Yongdong; Li Le; Zheng Jifang

2012-01-01

Hydroponic solution culture experiments were conducted on the growth of Eichhornia crassipes, Lemna minor L, Azolla imbircata, Potamogeton crispus, and Alligator alternanthera Herb in water with 0.15, 1.50 and 15.00 mg . L -1 concentrations of uranium, and on the uranium removal from the water by the aquatic plants. For the 21 days of hydroponic solution culture experiments, Azolla imbircata exhibited the strongest resistance to uranium and its growth inhibition rates induced by the water with 0.15, 1.50 and 15.00 mg · L -1 concentrations of uranium were 4.56%, 2.48%, 6.79%, respectively, and the uranium removal rates from the water by the plant amounted to 94%, 97% and 92%, respectively. Further experiments revealed that the most uranium removal could be achieved when 7.5 g Azolla imbircata was grown in 1 L of water, and the time required for the plant to reduce the uranium concentration in water with 1.25, 2.50, 5.00 and 10.00 mg · L -l concentrations of uranium below that stipulated in the national emission standards of China were 17, 19, 23 and 25 days, respectively. The results have laid foundation for further studies of phytoremediation of uranium contaminated water. (authors)

Celulitis por Microascus trigonosporus(anamorfo Scopulariopsis trigonospora

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DELIA CANLE CORTIÑAS

2013-06-01

Full Text Available Resumen: Microascus trigonosporus ( anamorfo Scopulariopsis trigonospora es un hongo filamentoso ubicuo que se encuentra en el suelo , plumas de aves, material vegetal e insectos. Aunque Scopulariopsis spp se consideran comúnmente hongos contaminantes , pueden causar ocasionalmente infecciones en humanos, en especial onicomicosis . Excepcionalmente se han descrito infecciones de piel, abscesos cerebrales, endocarditis ,sinusitis e infecciones diseminadas por Scopulariopsis spp , casi siempre en pacientes inmunodeprimidos . En los últimos años se han publicado un mayor número de casos de infecciones oportunistas por Scopulariopsis spp y otros hialohifomicetos multiresistentes. Todavía no está establecido cuál es el mejor régimen de tratamiento para las infecciones por Scopulariopsis spp. Presentamos un caso excepcional de celulitis por Microascus trigonosporus en un paciente con tratamiento prolongado con corticoides. Abstract: Microascus trigonosporus ( Anamorph Scopulariopsis trigonospora is a cosmopolitan filamentous fungus that inhabits soil, feathers ,plant material and insects. While Scopulariopsis is commonly considered as a contaminat fungus it may cause occasionally infections in humans ,especially onychomycosis .Skin lesions, brain abscess , endocarditis, sinusitis and disseminated infections due to Scopulariopsis species have been rarely reported , usually in immunocompromised patients . Over the last few years opportunistic infections by Scopulariopsis species and others multi-resistant hyalohyphomycetes have been increasingly reported . No clear treatment regimen for Scopulariopsis species infections has been established yet. We present a exceptional case of cellulitis due to Microascus trigonosporus in a patient with prolonged steroid therapy.

System design description for portable 1,000 CFM exhauster Skids POR-007/Skid E and POR-008/Skid F

International Nuclear Information System (INIS)

Nelson, O.D.

1998-01-01

The primary purpose of the two 1,000 CFM Exhauster Skids, POR-007-SKID E and POR-008-SKID F, is to provide backup to the waste tank primary ventilation systems for tanks 241-C-106 and 241-AY-102, and the AY-102 annulus in the event of a failure during the sluicing of tank 241-C-106 and subsequent transfer of sluiced waste to 241-AY-102. This redundancy is required since both of the tank ventilation systems have been declared as Safety Class systems

Variabilidad estacional de hospitalizaciones por varicela en el INSN, Lima-Perú

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Edwin Miranda-Choque

2013-04-01

Full Text Available Objetivo: Determinar las variabilidad estacional de hospitalizaciones por varicela. Diseño: Serie de casos. Institución: Instituto Nacional de Salud del Niño (INSN del Perú. Participantes: Niños hospitalizados por varicela. Intervenciones: Se estudió las hospitalizaciones por varicela de niños atendidos en el INSN del Perú desde el año 2001 hasta el 2011, país sin implementación de la vacunación contra la varicela; se identificó a los pacientes de la oficina de estadística. Principales medidas de resultados: Variabilidad estacional de hospitalizaciones de los niños atendidos por varicela. Resultados: Se estudió a 1 566 niños hospitalizados por varicela, siendo la mediana de edad de 2 años 6 meses, 46,4% (727/1 466 de sexo femenino, mediana de estancia hospitalaria seis días (RIQ:9,4. El grupo etario más afectado fue de 0 a 2 años, correspondiendo al 55% (864/1 566. En la curva de frecuencias de hospitalizaciones por varicela por meses evidenciamos la distribución estacional, con una tendencia al incremento cada vez mayor por año. Las hospitalizaciones por varicelas con al menos alguna complicación correspondieron a 68,5%(1 073/1 566. El porcentaje de fallecidos fue 0,83% (13/1 493. Conclusiones: Las hospitalizaciones por varicela en el INSN es una causa importante de morbilidad, con una tendencia estacional, siendo más frecuente en los meses de noviembre a febrero, con el incremento cada vez mayor por año y supone una importante carga económica.

Mortalidad por paludismo en Colombia, 1979-2008

OpenAIRE

Pablo Chaparro; Julio Padilla

2012-01-01

Introducción. En Colombia, el paludismo representa un grave problema de salud pública. Se estima que, aproximadamente, 60 % de la población se encuentra en riesgo de enfermar o de morir por esta causa. Objetivo. Describir la tendencia de la mortalidad por paludismo en Colombia desde 1979 hasta 2008. Materiales y métodos. Se llevó a cabo un estudio descriptivo para determinar la tendencia de las tasas de mortalidad. Las fuentes de información fueron las bases de datos de las defunciones...

Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing the Functions of Headwater Slope Wetlands on the South Carolina Coastal Plain

Science.gov (United States)

2011-09-01

i.e., swamp bay) ( Persea borbonia) in the overstory or midstory ERDC/EL TR-11-11 20 (Monk 1966, Nelson 1986, Wharton et al. 1977, USACE 1988). In...biflora swamp tupelo Persea borbonia redbay Pinus glabra spruce pine Pinus taeda loblolly pine Quercus laurifolia laurel oak Quercus michauxii swamp... American elm Group 22 Carpinus caroliniana American hornbeam 0.66 Celtis laevigata sugarberry Cornus foemina stiff dogwood Diospyros virginiana

El estrés por temperatura provoca necrosis en tabaco negro; cuantificación por análisis de imágenes

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Eduardo Ortega

2008-07-01

de imágenes ImageJ. Este programa es capaz de adquirir, mostrar, editar, resaltar y analizar imágenes. Se demostró que las hojas sometidas a 4 ºC, independientemente del tiempo de exposición, presentaron una mayor área necrosada (35% en comparación con el resto de los tratamientos. Las áreas con acumulación de H2O2 in situ fueron mayores en los tratamientos de estrés por temperaturas altas (45 y 60 oC. La detección y cuantificación de la necrosis producida por temperaturas extremas, combinando el método del azul de tripano con el análisis de imágenes, es una herramienta útil para valorar los daños producidos por estrés de temperaturas y pudiera ser utilizado para valorar los daños celulares provocados por otros tipos de estrés.Palabras clave: variedad-Habana-2000; especies reactivas de oxígeno; H2O2;; Habana-2000-variety; reactive oxygen species.

ESTUDIO DEL IMPACTO TÉCNICO DE MEZCLAS DE CONCRETO HIDRÁULICO POR LA SUSTITUCIÓN PARCIAL DE CEMENTO POR ZEOLITA

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I. Miranda Pasos

2014-06-01

Full Text Available La industria de la construcción cada vez más consciente de la necesidad de ejecutar obras con materiales que se obtengan y/o utilicen procesos industriales que minimicen la contaminación y, que contribuyan en el comportamiento de un producto como lo es el concreto hidráulico en la construcción, ha estado buscando alternativas de materiales que sustituyan total o parcialmente al cemento por otro cementante que contamine menos en su procesos de obtención y que conserve las propiedades o las mejore. Una alternativa para sustitución parcial del cemento es la zeolita, es un mineral que se obtiene por proceso de excavación y molienda de puzolana. La norma ASTM-618, define a las puzolanas como materiales silíceo o aluminio-silíceo que por sí solo poseen poco a ningún valor cementante, pero cuando se han dividido finamente y en presencia de agua e hidróxido de calcio (Cal reaccionan químicamente a temperatura ambiente para formar cementantes (Miranda, 2008. Recientemente se ha estudiado el efecto de adicionar mineral Cal-Zeolita para la elaboración del concreto, cuyos resultados son favorables al comportamiento mecánico y su durabilidad (Dopico J.J., et al. 2009. Para la elaboración de morteros para recubrimientos al incorporar arenas zeolíticas como sustituto de la arena tradicional (Tiburcio et al. 2008. El presente proyecto evaluó el comportamiento del concreto hidráulico en estado fresco y endurecido al sustituir de manera parcial cemento por zeolita. Se enfocó a la evaluación del comportamiento mecánico como al diseño de la mezcla de concreto hidráulico fabricado con cemento normal y con cemento-zeolita. Tomando en cuenta los resultados obtenidos, la zeolita incorporada en porcentajes entre el 5% y 10 % tiende a valores de resistencias muy cercanos al concreto normal, los modelos obtenidos así lo corroboran, por lo que se puede concluir la factibilidad de sustitución parcial de cemento por zeolita tomando en cuenta el

PERFIL DOS ATENDIMENTOS POR CAUSAS EXTERNAS EM HOSPITAL PÚBLICO

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Marlos Victor Fonsêca de Lima

2012-01-01

Full Text Available El objetivo fue identificar el perfil de los atendimientos por causas externas en la urgencia de un hospital público de referencia del Estado. Investigación descriptiva documental, con enfoque cuantitativo. En el análisis de datos, el período de enero a diciembre de 2009 se realizó 4.464 atendimientos por causas externas. La mayor frecuencia de las lesiones ocurrió en personas entre 21 y 40 años (37,70% y hombres (68,6%. Cuanto a las causas, las caídas (29% fue la mayor variable, seguido por accidente de motocicleta (17,98%, accidentes domiciliario (16,53%, agresión física (10,43% y accidente de motocicleta (8,84%. Se observó que 23,3% de los atendimientos realizados en la urgencia fueron de la población procedente de municipios aledaños. Hay, por lo tanto, la necesidad de mejorar la calidad de las informaciones acerca de las quejas motivadas por causas externas, principales causas de hospitalización y gastos en salud.

Justicia social y ambiental: mujeres por la soberanía alimentaria

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Angelica Velasco Sesma

2010-05-01

Full Text Available Dada la situación de crisis alimentaria, climática, energética y financiera a nivel internacional y el aumento del hambre en el mundo, numerosos movimientos sociales se han unido para luchar por la soberanía alimentaria y por la agricultura campesina. Las mujeres, como sujetos que desempeñan un rol fundamental en la actividad agraria, han manifestado, en la Declaración de las mujeres por la Soberanía Alimentaria, Nyéléni, Mali, 2007, que pretenden unir su lucha por la sostenibilidad con la reivindicación de sus derechos.

Escenarios de costos generados por el uso del costeo variable

OpenAIRE

Zea Lourido, Felipe

2013-01-01

Este trabajo demuestra cómo el costeo absorbente, considerado por expertos en la materia, uno de los métodos de costeo usado frecuentemente por las organizaciones, con el propósito de determinar el valor de los inventarios y del costo de productos vendidos que intervienen en el estado de resultados para usuarios externos (stakeholders), al compararlo con el costeo variable, preferido por algunos administradores para toma de decisiones internas y usado en la preparación del estado de resultado...

Elasticidad precio de la demanda por autopistas interurbanas en Chile

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Rodrigo Sanes

2013-01-01

transporte depende de la información que se disponga respecto a la elasticidad precio de la demanda por el uso de puentes, túneles y carreteras. El objetivo de este trabajo es estimar la elasticidad precio de la demanda por el uso de autopistas interurbanas en Chile utilizando el método de regresiones aparentemente no relacionadas (SUR y un panel de 48 datos mensuales obtenidos a partir de 21 plazas de peajes (48 x 21. Nuestros resultados muestran que, aún controlando por el precio de la gasolina y el nivel de actividad económica, la demanda por el uso de carreteras resulta ser muy inelástica al precio del peaje, con valores que oscilan entre -0,17 para automóviles y -0,05 para camiones.

Mortalidad por defectos del tubo neural en México, 1980-1997

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Ramírez-Espitia José A

2003-01-01

Full Text Available OBJETIVO: Describir la mortalidad en México por defectos del tubo neural, durante el periodo 1980-1997. MATERIAL Y MÉTODOS: Las tasas anuales de mortalidad estatales y nacionales, por defectos del tubo neural, se calcularon por 10 000 nacidos vivos. La tendencia temporal fue evaluada por el porcentaje de cambio anual obtenido mediante un modelo de regresión de Poisson. Se calculó la razón de mortalidad, tomando la media nacional como referencia. Las tasas y las razones se representaron gráficamente en mapas. RESULTADOS: Durante el periodo la tasa bruta de mortalidad por defectos del tubo neural fue de 5.8 por 10 000 nacidos vivos. La anencefalia fue el tipo de defecto más frecuente (37.7%, seguida de la espina bífida sin hidrocefalia (31.6%. La tendencia nacional de la mortalidad por defectos del tubo neural fue ascendente entre 1980 y 1990 (porcentaje de cambio anual 7.5 IC 95% 6.5, 8.6 y descendente entre 1990-1997 (porcentaje de cambio anual -2.3 IC 95% -3.6, -0.9. CONCLUSIONES: Las altas tasas de mortalidad por defectos del tubo neural fueron debidas principalmente a la elevada frecuencia de las anencefalias. El incremento observado parece no ser sólo atribuible a cuestiones puramente diagnósticas o de mejora en los registros. La influencia de factores asociados a estos defectos, como determinados polimorfismos genéticos, la deficiencia de ácido fólico, la obesidad materna, la exposición laboral a plaguicidas y la pobreza deberán evaluarse mediante estudios específicos.

Ependimoma celular parcialmente resecado complicado con meningoependimocoroiditis bacteriana por Pseudomonas aeruginosa e infección sistémica por citomegalovirus

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Francisco Javier Otero-Mendoza

2017-06-01

Full Text Available Niño de 1 año 10 meses de edad, originario de Irapuato, Guanajuato, sin antecedentes de importancia para el padecimiento actual. Inició dos meses previos a su ingreso con crisis convulsivas tónico-clónicas generalizadas de 15 segundos de duración durante el sueño. Se realizó electroencefalograma que reportó actividad epileptiforme, por lo que se dio tratamiento con ácido valproico. Una semana previa al ingreso se agregó ataxia troncal impidiendo la marcha, por lo que se realizó una tomografía axial computarizada de cráneo en la que se observó un tumor en fosa posterior con densidad heterogénea y áreas de necrosis central que obliteraba el cuarto ventrículo, ocasionando efecto de masa y desplazamiento ventral del tallo cerebral. Por tal motivo, fue referido a nuestra institución.

Higiene alimentaria para la prevención de trastornos digestivos infecciosos y por toxinas

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G. Manuel Moreno, Dr.

2010-09-01

Full Text Available El principal factor que interviene en el origen y prevención de las enfermedades trasmitidas por los alimentos es la higiene alimentaria. Dichas enfermedades son causadas por la ingestión de alimentos o agua contaminados con microorganismos patógenos ocasionando una infección o por la ingestión de alimentos contaminados con toxinas. Los principales agentes involucrados son Escherichia Coli, Campylobacter, Salmonella, Shigella, Listeria Monocytogenes, Norovirus, virus Hepatitis A, Astrovirus, Rotavirus, y Virus Coxsackie. Toxinas producidas por hongos o por microflora marina y los contaminantes orgánicos persistentes pueden también causar serios problemas de salud. La inocuidad alimentaría ha tomado relevancia debido a una mayor exigencia por consumidores cada día más informados y por las demandas del comercio exterior. Medidas que aseguren una adecuada higiene alimentaría nos permitirá prevenir enfermedades, principalmente digestivas, causadas por variados agentes en los alimentos. Esto se logra por la implementación de las medidas propuestas por la Comisión Internacional conocida como Codex Alimentarius.

Endoftalmitis poscirugía de catarata por Sphingomonas paucimobilis

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Omar Mauri Garrido

Full Text Available Se presenta la caracterización y manejo terapéutico de un caso de endoftalmitis bacteriana posoperatoria causada por el germen Sphingomonas paucimobilis. La endoftalmitis es la inflamación de los tejidos intraoculares, considerada como la más devastadora de las complicaciones posoperatorias; posee pronóstico visual muy reservado y un elevado riesgo de secuela. Las Sphingomonas paucimobilis son bacterias gramnegativas con forma de bacilo, quimioheterótrofa y estrictamente aerobias que causan enfermedades en los seres humanos, principalmente infecciones hospitalarias que típicamente son tratadas fácilmente con antibióticos. Por sus capacidades biodegradantes y biosintéticas, son pocos los reportes hallados de infección intraocular por este germen. El pronóstico visual es favorable con un diagnóstico precoz y la aplicación del tratamiento adecuado. En este artículo se presentan un caso de endoftalmitis poscirugía de catarata por Sphingomonas paucimobilis reportado en Cuba en el mes de septiembre de 2009.

Eritema multiforme mayor desencadenado por antimicrobianos

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Ronaldo de Carvalho Raimundo

2010-03-01

Full Text Available El eritema multiforme, aparece como una enfermedad sistémica con la participación de la piel y las membranas mucosas en relación con varios factores como las infecciones bacterianas o virales, y en particular la administración de drogas, analgésicos y antibióticos en general. Se presenta un paciente masculino de 29 años de edad con eritema multiforme mayor desencadenado por antimicrobianos con la aparición de lesiones vesiculares-bulloso-ulcerosas en las regiones de los labios, encías, la lengua y la mucosa genital en tratamiento de una infección del tracto urinario con norfloxacino 400 mg por una semana. Fue realizado un tratamiento de soporte con el uso de colutorios para la higienización bucal y pomada a base de corticoide para protección de las úlceras, antihistamínicos y orientación nutricional de dieta líquida hipercalórica e hiperproteica. Este síndrome está caracterizado como un proceso eruptivo buloso agudo que compromete la calidad de vida del paciente y no hay pruebas de laboratorio específicas por lo que su diagnóstico debe estar basado en la revisión minuciosa de la anamnesis y en los hallazgos clínicos.

Tendencias de la mortalidad por fiebre amarilla, Colombia, 1998-2009

Directory of Open Access Journals (Sweden)

Ángela María Segura

2013-08-01

Full Text Available Introducción. La fiebre amarilla es una enfermedad tropical desatendida, razón por la cual el conocer las tendencias de mortalidad por fiebre amarilla en Colombia, constituye una importante fuente de información para la toma de decisiones y las intervenciones en salud pública. Objetivo. Analizar las tendencias de mortalidad fiebre amarilla en Colombia (1998-2009 y las diferencias que presentan las fuentes de información de morbilidad y mortalidad en el país, que afectan indicadores como el de letalidad. Materiales y métodos. Es un estudio descriptivo de las muertes por fiebre amarilla, según el Departamento Administrativo Nacional de Estadística, y de la incidencia de la enfermedad, según el Instituto Nacional de Salud. Se usaron fuentes secundarias de información en el cálculo de proporciones de las características sociodemográficas de los fallecidos y las medidas epidemiológicas de letalidad, incidencia y mortalidad por fiebre amarilla, por departamento de residencia de los fallecidos. Resultados. Las muertes por fiebre amarilla se presentan principalmente en hombres, en edad de trabajar, residentes en zonas rurales dispersas, afiliados al régimen vinculado, residentes en las zonas oriental, suroriental, norte y central del país. Se observaron inconsistencias en los informes reportados que afectan el análisis comparativo. Conclusión. Los habitantes de los departamentos ubicados en los territorios nacionales y en Norte de Santander presentan mayor riesgo de enfermar y de morir por fiebre amarilla, pero esta información pudiera estar subestimada, según la fuente de información utilizada en su cálculo.   doi: http://dx.doi.org/10.7705/biomedica.v33i0.698

Industrial refrigeration by absorption/compression; Refrigeracion industrial por absorcion/compresion

Energy Technology Data Exchange (ETDEWEB)

Ayala Delgado, Ramon; Heard, Christopher Lionel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1996-12-31

The use of the absorption/compression refrigeration in the industrial area is analyzed. It is estimated than in Mexico 50% of the food is wasted for lack of refrigeration in the producing centers and by the inefficient distribution system, as well as for the hot climate. The functioning of the absorption refrigeration and the hybrid system absorption/compression which can operate with the two thermodynamic cycles in variable proportions, depending on the specific application, looking for operational advantages and energy efficiency is described. This type of technology could be applied in Mexico due to the lack of industrial refrigeration and to the need of substituting compressors in some companies which have up to 20 years of use [Espanol] Se analiza el uso de la refrigeracion por absorcion/compresion en el area industrial. En Mexico se estima que se desperdicia el 50% de los alimentos por falta de refrigeracion en los centros productores y por el deficiente sistema de distribucion, asi como por el clima calido. Se describe el funcionamiento de la refrigeracion por absorcion y la refrigeracion por absorcion/compresion o sistema hibrido, el cual puede funcionar con los dos tipos de ciclos termodinamicos, en proporciones variables, dependiendo de la aplicacion especifica, buscando ventajas de operacion y eficiencia energetica. Este tipo de tecnologia podria aplicarse en Mexico debido a la falta de refrigeracion industrial y a la necesidad de sustituir compresores en algunas empresas los cuales tienen hasta 20 anos de uso

Industrial refrigeration by absorption/compression; Refrigeracion industrial por absorcion/compresion

Energy Technology Data Exchange (ETDEWEB)

Ayala Delgado, Ramon; Heard, Christopher Lionel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

1997-12-31

The use of the absorption/compression refrigeration in the industrial area is analyzed. It is estimated than in Mexico 50% of the food is wasted for lack of refrigeration in the producing centers and by the inefficient distribution system, as well as for the hot climate. The functioning of the absorption refrigeration and the hybrid system absorption/compression which can operate with the two thermodynamic cycles in variable proportions, depending on the specific application, looking for operational advantages and energy efficiency is described. This type of technology could be applied in Mexico due to the lack of industrial refrigeration and to the need of substituting compressors in some companies which have up to 20 years of use [Espanol] Se analiza el uso de la refrigeracion por absorcion/compresion en el area industrial. En Mexico se estima que se desperdicia el 50% de los alimentos por falta de refrigeracion en los centros productores y por el deficiente sistema de distribucion, asi como por el clima calido. Se describe el funcionamiento de la refrigeracion por absorcion y la refrigeracion por absorcion/compresion o sistema hibrido, el cual puede funcionar con los dos tipos de ciclos termodinamicos, en proporciones variables, dependiendo de la aplicacion especifica, buscando ventajas de operacion y eficiencia energetica. Este tipo de tecnologia podria aplicarse en Mexico debido a la falta de refrigeracion industrial y a la necesidad de sustituir compresores en algunas empresas los cuales tienen hasta 20 anos de uso

¿Por qué hay canciones que perduran?

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Josune Albisu Barandiaran

2015-11-01

Full Text Available El principal objetivo de este artículo es analizar una canción, Txoria txori, para deducir cuales han sido las principales características que la han convertido en “Himno popular”, permitiéndola perdurar en el tiempo. Dentro de las principales características, dos han sido verdaderamente reseñables: por una parte, la plasticidad, y por otra, la sencillez y estructura clara de la canción.

Manifestaciones oftalmológicas por virus de Epstein-Barr

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Adrianne MayulySuñetÁlvarez

Full Text Available Se trata de un paciente masculino de 26 años que acude por disminución brusca de la visión del ojo derecho. Seingresó como una uveítis posterior dada por exudación extensa en área macular del ojo derecho, acompañada de edema del disco óptico, vasculitis aledaña a la lesión y hemorragias dispersas en llama en el polo posterior. La etiología era controversial y, el tratamiento más apropiado era debatible, por lo que se le realizaron estudios como retinografías seriadas, angiografías fluoresceínicas y reacción en cadena de polimerasa a una muestra del humor acuoso, que confirmó la etiología viral; lo que resultó en una agudeza visual final de 0,1. Posterior a 6 meses del cuadro inicial, el paciente presentó queratitis intraestromal en forma numular -que recurre ante episodios de stress-, para desaparecer luego de terapia tópica con antiinflamatorios no esteroideos y esteroideos.La baja incidencia de casos reportados con uveítis posterior por virus de Epstein Barr resulta de un pobre conocimiento de la presentación de la enfermedad, por tanto un retraso en la instauración del tratamiento. En estos casos la prueba de oro es la reacción de cadena de polimerasa.

LUCHA POR LA TIERRA EN EL NORTE DE URUGUAY

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Gabriel Oyhantçabal Benelli

2011-12-01

Full Text Available Este artículo analiza la trayectoria de la lucha por la tierra en Bella Unión, una región característica en Uruguay por la producción de caña de azúcar, a través de los movimientos de clase de sus principales protagonistas: los cortadores de caña sindicalizados en la Unión de Trabajadores Azucareros de Artigas (UTAA. El recorrido histórico hace énfasis en dos períodos históricos diferentes: 1961-1973 y 2005-presente. El primero va desde la fundación del sindicato hasta el golpe militar. Se da en un contexto de auge de la lucha de masas en Uruguay en el cual los trabajadores rurales se organizan en la UTAA levantando, entre otras, la bandera de la Reforma Agraria. El segundo período está marcado por la llegada al gobierno nacional del Frente Amplio, una coalición social-demócrata que reactiva la producción de caña de azúcar en Bella Unión. Este cambio supone una oportunidad para las luchas sociales que la UTAA aprovecha con ocupaciones de tierra favoreciendo un proceso de colonización para los trabajadores rurales. Sin embargo el acceso a la tierra genera nuevas contradicciones, y por tanto nuevos desafíos, por los cambios en la forma de subsunción del trabajo al capital.

Riesgos antrópicos generados por la actividad minera

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Ana Violeta Argüello Mejía

2013-10-01

Full Text Available Las actividades productivas generan riesgos antrópicos [1] a mediano y largo plazo. La zona de estudio se ubica en las Parroquias de Pomasqui, San Antonio y Calacalí, donde se han producido riesgos debido a las actividades humanas, en este caso, por la explotación de las canteras para abastecer el mercado de la construcción del Distrito Metropolitano de Quito. La investigación propone determinar los riesgos antrópicos generados por la actividad minera. Los pobladores de la zona identifican que la minería artesanal en sus inicios constituyó una fuente de trabajo, donde sus familias también se involucraban. Actualmente, se observa que en la mayoría de las canteras se utiliza maquinaria especializada y no participan los trabajadores de la zona. Los taludes de las canteras son de 80o y 90o grados, generando amenazas para los trabajadores y moradores de las viviendas aledañas. Uno de los mayores impactos es la contaminación del aire, sin embargo, el suelo y los cursos de agua están siendo afectados por los desperdicios que produce la actividad minera. La población, que está expuesta permanentemente al polvo ocasionado por las canteras y al transporte de material, acusa enfermedades de tipo respiratorio. Así mismo, el ruido ocasionado por el transporte constituye una molestia constante para los pobladores.

Celulitis por cuerpo extraño

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Miguel B. Carrasco Guzmán

2016-01-01

Full Text Available Las infecciones de la piel y el tejido celular subcutáneo surgen como un grupo importante de afecciones con una alta morbilidad en edades pediátricas, generalmente relacionada con traumatismo y cuerpos extraños. Se presenta el caso de una escolar femenina de 6 años de edad, con síntomas y signos clínicos que sugieren celulitis en el muslo derecho,  por su evolución tórpida se le realizó el estudio ultrasonográfico que confirmó el diagnóstico etiológico de una celulitis secundaria a un traumatismo, provocada por la introducción de un gran cuerpo extraño, que pasó inadvertido para a familia de la menor.

Oral administration of recombinant Neisseria meningitidis PorA genetically fused to H. pylori HpaA antigen increases antibody levels in mouse serum, suggesting that PorA behaves as a putative adjuvant.

Science.gov (United States)

Vasquez, Abel E; Manzo, Ricardo A; Soto, Daniel A; Barrientos, Magaly J; Maldonado, Aurora E; Mosqueira, Macarena; Avila, Anastasia; Touma, Jorge; Bruce, Elsa; Harris, Paul R; Venegas, Alejandro

2015-01-01

The Neisseria meningitidis outer membrane protein PorA from a Chilean strain was purified as a recombinant protein. PorA mixed with AbISCO induced bactericidal antibodies against N. meningitidis in mice. When PorA was fused to the Helicobacter pylori HpaA antigen gene, the specific response against H. pylori protein increased. Splenocytes from PorA-immunized mice were stimulated with PorA, and an increase in the secretion of IL-4 was observed compared with that of IFN-γ. Moreover, in an immunoglobulin sub-typing analysis, a substantially higher IgG1 level was found compared with IgG2a levels, suggesting a Th2-type immune response. This study revealed a peculiar behavior of the purified recombinant PorA protein per se in the absence of AbISCO as an adjuvant. Therefore, the resistance of PorA to proteolytic enzymes, such as those in the gastrointestinal tract, was analyzed, because this is an important feature for an oral protein adjuvant. Finally, we found that PorA fused to the H. pylori HpaA antigen, when expressed in Lactococcus lactis and administered orally, could enhance the antibody response against the HpaA antigen approximately 3 fold. These observations strongly suggest that PorA behaves as an effective oral adjuvant.

Choque cardiogênico por dissulfiram Shockcardiogénico por disulfiram Cardiogenic shock caused by disulfiram

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Ana Jerónimo

2009-03-01

Full Text Available A intoxicação medicamentosa por dissulfiram é uma situação rara, mas, que pode se apresentar com manifestações cardiovasculares graves e potencialmente fatais, como choque cardiogênico. É apresentado o caso de uma paciente com choque refratário, após intoxicação voluntária por dissulfiram. A avaliação clínica e bioquímica, junto à avaliação ecocardiográfica e à monitorização invasiva, confirmaram tratar-se de um choque cardiogênico associado a esse fármaco. São discutidos os mecanismos de ação conhecidos do dissulfiram e descritos os principais efeitos colaterais, especialmente os cardiovasculares, alertando para a importância da suspeição diagnóstica e da abordagem terapêutica imediata mais adequada nesse contexto.La intoxicación medicamentosa por disulfiram es una situación rara, aunque puede presentarse con manifestaciones cardiovasculares graves y potencialmente fatales, como el shock cardiogénico. Este relato presenta el caso de una paciente con shock refractario, tras intoxicación voluntaria por disulfiram. La evaluación clínica y bioquímica, junto a la evaluación ecocardiográfica y el monitoreo invasivo, confirmaron tratarse de un shock cardiogénico asociado a ese fármaco. A lo largo del presente relato se discuten los mecanismos de acción del disulfiram conocidos, así como se describen los principales efectos colaterales, específicamente los cardiovasculares. En este sentido, también se alerta para la importancia de la sospecha diagnóstica y del abordaje terapéutico inmediato más adecuado a este contexto.Drug intoxication with disulfiram is a rare condition that may lead to severe and potentially fatal cardiovascular manifestations such as cardiogenic shock. We report the case of a female patient with refractory shock after deliberate self-poisoning with disulfiram. Clinical, biochemical and echocardiographic assessment, as well as invasive monitoring confirmed cardiogenic shock

Elasticidad precio de la demanda por autopistas interurbanas en Chile

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Rodrigo Saens

2013-07-01

Full Text Available La efectividad de un esquema de tarificación vial para optimizar el uso de infraestructura de transporte depende de la información que se disponga respecto a la elasticidad precio de la demanda por el uso de puentes, túneles y carreteras. El objetivo de este trabajo es estimar la elasticidad precio de la demanda por el uso de autopistas interurbanas en Chile utilizando el método de regresiones aparentemente no relacionadas (SUR y un panel de 48 datos mensuales obtenidos a partir de 21 plazas de peajes (48 x 21. Nuestros resultados muestran que, aún controlando por el precio de la gasolina y el nivel de actividad económica, la demanda por el uso de carreteras resulta ser muy inelástica al precio del peaje, con valores que oscilan entre -0,17 para automóviles y -0,05 para camiones.

Fiebres hemorrágicas por Arenavirus en Latinoamérica

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Ella Soto

2010-01-01

Full Text Available Las fiebres hemorrágicas virales producidas por Arenavirus incluyen a los virus endémicos en África (Lassa y el virus de la coriomeningitis linfocítica (LCMV, de distribución mundial, y los Arenavirus del Nuevo Mundo o Complejo Tacaribe, que incluye a los virus endémicos en las Américas (Junín, Machupo, Guanarito, Sabiá, Pichinde, entre otros. Los huéspedes naturales son los roedores y la infección en humanos se produce por el contacto con la orina y excretas. Las manifestaciones clínicas inicialmente son indistinguibles de otras fiebres hemorrágicas producidas por bacterias, parásitos y otros virus, constituyéndose esto en un problema de salud pública, por lo que se requiere realizar el diagnóstico diferencial utilizando técnicas serológicas y moleculares.

Itinerario de la Patria: por tierras del golfo lejano

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Adel López Gómez

1965-06-01

Full Text Available Veinticinco años atrás solo primaba en estas infinitudes el imperio de la selva. Desde Dabeiba tórrido hasta Turbo sudoroso y lacustre se empleaba casi una semana a lomo de mula o a quimba de peatón, por una sombría trocha de miasmas y de lodo, abierta a machete por entre la áspera e interminable manigua. Por allí pasaron una y otra vez los pálidos hombres de nuestros enganches, cuando en 1939 iniciamos, a la orilla del Golfo de Urabá, la ingente tarea de construír una carretera hacia el interior para poner al alcance de las llantas antioqueñas la orilla salvaje del Atlántico maicero.

2015. 2. Por qué celebrar primarias

OpenAIRE

Sanz Díaz, Benito

2015-01-01

¿Por qué celebrar primarias? ¿Beneficia o perjudica a las organizaciones y partidos que las promueven?, ¿Mejora la participación?, ¿La elección de los dirigentes evita la oligarquización y la Ley de Hierro de los partidos políticos que enunció Robert Michels? Un sistema de selección de candidatos con origen en la política norteamericana, fue adaptado por el PSOE, y a continuación iría extendiéndose su práctica a los todos los partidos políticos. Ignacio Urquizu señalaba sobre l...

14 Nobel, preocupados por el CERN

CERN Multimedia

Rivera, A

2003-01-01

"E l presidente del Consejo del CERN (Laboratorio Europeo de Fisica de Particulas, junto a Ginebra), Maurice Bourquin, ha recibido una carta firmada por un grupo de cientificos muy especiales: 14 premios Nobel de Fisica" (1 page).

Mortalidad intrahospitalaria por accidente cerebrovascular

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Federico Rodríguez Lucci

2013-08-01

Full Text Available La mortalidad global por accidente cerebrovascular (ACV ha disminuido en las últimas tres décadas, probablemente debido a un mejor control de los factores de riesgo vascular. La mortalidad hospitalaria por ACV ha sido tradicionalmente estimada entre 6 y 14% en la mayoría de las series comunicadas. Sin embargo, los datos de ensayos clínicos recientes sugieren que esta cifra sería sustancialmente menor. Se revisaron datos de pacientes internados con diagnóstico de ACV del Banco de Datos de Stroke de FLENI y los registros institucionales de mortalidad entre los años 2000 y 2010. Los subtipos de ACV isquémicos se clasificaron según criterios TOAST y los ACV hemorrágicos en hematomas intrapanquimatosos, hemorragias subaracnoideas aneurismáticas, malformaciones arteriovenosas y otros hematomas intraparenquimatosos. Se analizaron 1514 pacientes, 1079 (71% con ACV isquémico (grandes vasos 39%, cardioembólicos 27%, lacunares 9%, etiología indeterminada 14%, otras etiologías 11% y 435 (29% con ACV hemorrágico (intraparenquimatosos 27%, hemorragia subaracnoidea 30%, malformaciones arteriovenosas 25% y otros hematomas espontáneos 18%. Se registraron 38 muertes intrahospitalarias (17 ACV isquémicos y 21 ACV hemorrágicos, representando una mortalidad global del 2.5% (1.7% en ACV isquémicos y 4.8% en ACV hemorrágicos. No se registraron muertes asociadas al uso de fibrinolíticos endovenosos. La mortalidad intrahospitalaria en pacientes con ACV isquémico y hemorrágico en nuestro centro fue baja. El manejo en un centro dedicado a las enfermedades neurológicas y el enfoque multidisciplinario por personal médico y no médico entrenado en el cuidado de la enfermedad cerebrovascular podrían explicar, al menos en parte, estos resultados.

¿Por qué el satélite Cóndor?

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Leonardo Ferrerira

2015-01-01

Full Text Available Estados Unidos y Rusia representan el 15 por ciento de la población mundial sin embargo utilizan el 50 por ciento de la órbita geoestacionaria, mientras todo el Tercer Mundo emplea menos del 10 por ciento. Los países del Pacto Andino se encuentran trabajando conjuntamente en el uso compartido de un solo sistemas satelital CONDOR. Pero los críticos norteamericanos consideran que es una manera ineficiente e irracional congestionar el espectro orbital. El artículo se centra en describir este proyecto y la lógica Andina, la soberanía

Hipoglucemia inducida por carcinoma adrenal

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Jimena Soutelo

2013-08-01

Full Text Available El carcinoma suprarrenal es una neoplasia maligna infrecuente y de mal pronóstico. La presentación clínica más común es originada por la producción hormonal excesiva, mientras que el desarrollo de hipoglucemia sintomática es excepcional. Presentamos el caso de una mujer de 37 años que ingresó al hospital por síntomas de hipoglucemias graves, hipertensión arterial, hipopotasemia y amenorrea secundaria. En el laboratorio se halló hipoglucemia con insulina inhibida y niveles de andrógenos en rango tumoral. La tomografía computarizada (TC de abdomen y pelvis mostró voluminosa formación heterogénea de aspecto sólido sin plano de clivaje con respecto al parénquima hepático e intenso realce con contraste. Luego de la extirpación de la masa retroperitoneal, evolucionó con valores de glucemia y potasemia normales, estabilizó la presión arterial y recuperó los ciclos menstruales.

Cefaleia por uso excessivo de medicamentos

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Ariane Maria Fonseca MIRANDA

2015-01-01

Full Text Available Uma variante da cefaleia crônica diária, a cefaleia por uso excessivo de medicamentos é uma manifestação clínica de frequência ≥ 15 dias por mês, durante 3 meses. Possui um diagnóstico deficiente e um tratamento dividido em etapas, sendo a desintoxicação, a etapa de fundamental importância. Este artigo apresenta uma revisão sobre o tema, contribuindo para o esclarecimento das principais manifestações clínicas, principais teorias envolvendo sua fisiopatologia e a terapêutica farmacológica empregada. A metodologia utilizada foi uma revisão de publicações europeias e americanas, no período de 2001 a 2013, nos idiomas português, inglês e espanhol. Todos os medicamentos utilizados no tratamento sintomático das cefaleias são capazes de cronificar uma cefaleia preexistente, desde que sejam utilizados excessivamente, de forma regular e continuada. A suspensão de tais agentes terapêuticos resultará em melhoria na maioria dos pacientes, porém pode ser necessária a introdução de uma terapia de suporte de transição e/ou terapia profilática. Os tratamentos nao farmacológicos, quando associados ao farmacológico, ampliam a possibilidade de resultados satisfatórios, evitando recaídas.

Primer reporte de un caso importado de Malaria por Plasmodium ovale curtisi en Paraguay, confirmado por diagnóstico molecular

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Florencia del Puerto

2015-04-01

Full Text Available En países donde el Plasmodium ovale no es común, los microscopistas tienden a identificarlo de manera errónea como Plasmodium vivax. En este trabajo reportamos la identificación de la especie P. ovale curtisi por el método de PCR múltiple semianidada (SnM-PCR y la secuenciación de la subunidad pequeña del gen del ARN 18S, en un paciente paraguayo de 44 años de edad que vino en el 2.013 de Guinea Ecuatorial, África Occidental, a quien se le diagnosticó una infección por P. vivax por microscopía convencional. El empleo de métodos moleculares para la identificación de casos importados de infección con especies del género Plasmodium es uno de los objetivos principales en el control y la prevención de la malaria en Paraguay, teniendo en cuenta que el país se encuentra en fase de pre-eliminación de la enfermedad.

Contractura axilar por quemadura tratada con Integra®

OpenAIRE

Roa G,Ricardo; Las Heras F,Rocío; Piñeros B,José L; Correa S,Gerardo; Norambuena B,Hernán; Marré N,Diego

2011-01-01

Las quemaduras axilares severas son un accidente infrecuente que evolucionan a la retracción generando deficiencias cosméticas y funcionales. Estas cicatrices son difíciles de tratar por las características anatómicas del área, donde la corrección de un vector de movimiento puede alterar otro. Objetivo: Mostrar nuestros resultados utilizando el sustituto cutáneo Integra® en el tratamiento de cicatrices retráctiles axilares por quemadura. Pacientes y Métodos: Se recolectaron antecedentes médic...

¿Por qué fracasan las campañas?

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Andrea Castelnuovo

2015-01-01

Full Text Available Analiza tres experiencias en las que puede evidenciarse por qué fracasan las campañas sociales: por la misma razón, fueron concebidas con mensajes destinados a una población que vive y percibe el mundo desde el nivel económico y socio-cultural distinto, el emisor no empata con los perfiles del receptor. Es fundamental empezar por definir qué se debe decir, a quién, y cómo, para luego encontrar los medios más adecuados para su difusión. La espectacularidad y etnocentrismo, las campañas sociales seguirán sirviendo exclusivamente para mejorar las finanzas de los medios de comunicación masivos y secundariamente, para brindar materia prima a humoristas y contestarios.

Estudo dos linfócitos circulantes por anticorpos monoclonais na miastenia grave

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Paulo E. Marchiori

1988-09-01

Full Text Available Os autores avaliam os linfócitos T (CD3, CD4, CD8, CD4/8 por anticorpos monoclonais e rosácea em 20 pacientes e linfócitos B por Fab' por imunofluorescência em 9 pacientes com miastenia grave. Observam elevação significante na população de linfócito B e redução nos linfócitos T totais CD3+ por rosáceas. Não foram observadas modificações nas subpopulações celulares com timectomia e corticosteróides.

México en la segunda Guerra Mundial visto por la Diplomacia venezolana

OpenAIRE

Silva L, Dómel

2013-01-01

Partiendo del análisis de una serie de documentos concernientes a las comunicaciones entre la llamada “Legación de Venezuela” en México y la Cancillería de Venezuela durante los años de la Segunda Guerra Mundial (1939-1945), se esbozará las estrategias en común para ambas naciones; como fue la política de seguridad de cada Estado, enmarcada dentro de la política de seguridad continental. México por su importancia geoestratégica; por el petróleo, por su cercanía con los Estados Unidos y por la...

Osteomalacia inducida por tumor: hemangiopericitoma rinosinusal Tumor-induced osteomalacia: rhinosinusal hemangiopericytoma

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Enriqueta M. Serafini

2013-02-01

Full Text Available La osteomalacia inducida por tumor es una rara enfermedad del metabolismo óseo caracterizada por el aumento en la excreción de fosfato a nivel renal seguido de hipofosfatemia. Es causada por agentes fosfatúricos producidos por determinados tumores. La resección total del tumor resulta en la completa reversión de las anormalidades bioquímicas, la desaparición de las manifestaciones clínicas y los hallazgos en los estudios por imágenes. Presentamos el caso de un varón de 61 años con cuadro clínico y laboratorio compatibles con osteomalacia oncogénica inducida por tumor mesenquimático de localización rinosinusal. En nuestro caso el diagnóstico histológico correspondió a una neoplasia de tipo vascular: hemangiopericitoma.Tumor-induced osteomalacia is a rare disease of bone metabolism. The characteristic of this disease is an increase in phosphate excretion followed by hypophosphatemia, due to phosphaturic agents produced by different types of tumors. Tumor resection results in complete resolution of clinical, biochemical and radiological abnormalities. We present the case of a 61 year old man with signs, symptoms and laboratory findings consistent with oncogenic osteomalacia due to a rhino-sinusal mesenchymal tumor. The histological diagnosis showed a vascular neoplasm: hemangiopericytoma.

Disfunção ventricular esquerda transitória por cardiomiopatia induzida por estresse Transient left ventricular dysfunction due to stress-induced cardiomyopathy

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Marcus Vinicius Simões

2007-10-01

Full Text Available Apresenta-se o caso de uma paciente de 71 anos que preencheu os critérios diagnósticos para cardiomiopatia induzida por estresse que foi desencadeada por intenso estresse emocional após atropelamento por bicicleta. O quadro clínico mimetizou o infarto agudo do miocárdio, manifestando-se com dor precordial, supradesnivelamento do segmento ST, seguido por ondas T profundas e prolongamento do intervalo QT, elevação discreta de enzimas cardíacas e cursando com disfunção sistólica apical do ventrículo esquerdo e hipercinesia das porções basais (conferindo o aspecto de "abaloamento apical", mas na ausência de obstrução coronariana subepicárdica. A função ventricular normalizou-se após a segunda semana de evolução.The case presented here is of a 71-yr-old female patient who met the diagnostic criteria for stress-induced cardiomyopathy, which was triggered by intense emotional stress after being hit by a bicycle. The clinical picture mimicked that of an acute myocardial infarction, manifesting as precordial pain, ST-segment depression followed by deep negative T waves and prolonging of the QT interval, slight increase in cardiac enzymes and coursing with transient apical ballooning of the left ventricle and hyperkinesis of the basal walls (conferring the aspect of "apical ballooning", although in the absence of subepicardial coronary obstruction. Ventricular function normalized after the second week of clinical evolution.

Mortalidad por suicidio en la provincia de Pinar del Río

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Ana Carmen Valdés Vento

2003-02-01

Full Text Available Se trata de una investigación descriptiva y retrospectiva sobre el comportamiento de la mortalidad por suicidio en la provincia Pinar del Río durante el año 2001, de acuerdo con una serie de variables seleccionadas. Se estudiaron todos los fallecidos por esa causa en el período señalado, que fueron un total de 110 para una tasa de 14,9 por 100 000 habitantes, por lo que es la séptima causa de muerte en la provincia. Llama la atención el amplio predominio del sexo masculino, de la incidencia en la tercera edad, y el hecho de no haber tenido este año el municipio Sandino fallecido alguno por esta causa, así como que el municipio de mayor número de fallecidos por este motivo fue Viñales con una tasa de 26,0 por 100 000 habitantes.A retrospective descriptive research work on the situation of mortality from suicide in Pinar del Río province during 2001 was carried out based on a group of selected variables. All the deaths form this cause, which amounted to 110 persons for a rate of 14.9 per 100 000 pop, were studied. Suicide was the seventh cause of death in the province. It should be underlined that males prevailed, the incidence of the elderly was high and that Sandino municipality had no death from suicide in this year whereas Viñales municipality showed the highest number of deceased, with a mortality rate of 26 per 100 000 pop.

Lucro por ação

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Gabriel Moreira Campos

2001-08-01

Full Text Available Este trabalho tem por objetivo demonstrar os principais conceitos acerca do Lucro por Ação (Earnings per Share, o qual se apresenta como um quociente de grande utilidade nas entidades. Serão demonstrados aspectos sobre o assunto presentes no Brasil, bem como as normas aplicáveis nos Estados Unidos, emanadas do Financial Accounting Standards Board (FASB, e as normas internacionais, emanadas do International Accounting Standards Committee (IASC. De forma a possibilitar uma visualização mais completa dos conceitos envolvidos, serão desenvolvidos exemplos de sua aplicação. O Lucro (Resultado por Ação pode ser calculado em sua forma básica e em sua forma diluída. Na forma básica, não são considerados os efeitos dos instrumentos potencialmente dilutivos, ao passo que, no cálculo do Lucro (Resultado por Ação Diluído, são. Como instrumentos financeiros potencialmente dilutivos temos as ações preferenciais conversíveis, as debêntures conversíveis e os bônus de subscrição, que podem ser convertidos em ações ordinárias, caracterizando, assim, o próprio potencial dilutivo desses instrumentos. Dessa forma, o trabalho em questão foi dividido em três partes principais, sendo que nas duas últimas constam os referidos exemplos de cálculo do Lucro por Ação em sua forma básica e em sua forma diluída: • aspectos observados no Brasil; • normas emanadas do FASB; • normas emanadas do IASC.The objective of this paper is to demonstrate the principal concepts about Earnings per Share, which is presented as a quotient of great usefulness for the companies. The subject is presented in three parts: in the first part, we will demonstrate relevant aspects that are present in Brazil. In the second part, the applicable standards in the United States will be discussed, which are issued by the Financial Accounting Standards Board (FASB. In the third part, the international standards are dealt with, which are issued by the

Síndrome oculoglandular de Parinaud causada por esporotricose

OpenAIRE

Ribeiro,Alexandre Sampaio de Abreu; Bisol,Tiago; Menezes,Marcela Sant'Ana

2010-01-01

A síndrome oculoglandular de Parinaud é uma doença ocular rara causada por diferentes agentes etiológicos, entre eles bactérias, vírus e fungos. É caracterizada por uma conjuntivite granulomatosa, acompanhada de linfadenopatia pré-auricular adjacente e pode trazer sequelas caso não seja prontamente tratada. Neste artigo é relatado o caso de uma jovem técnica de enfermagem e estudante de medicina veterinária apresentando a síndrome oculoglandular de Parinaud causada pelo fungo Sporothrix schen...

Por qué todas las cuentas son falsas

OpenAIRE

Aerde, Michel van

1994-01-01

Los principales criterios para evaluación y decisión, en la sociedad actual, son inspirados por cálculos económicos. Mucho nos preocupamos de cuentas pero muy poco nos preguntamos de lo que es el dinero. Muy poco reflexionamos filosóficamente, ontológicamente, sobre la naturaleza misma del dinero. ¿Qué es esto que pretende ser la base de nuestra sociedad? El dinero es mentiroso por naturaleza. Es una representación de mucha vida, que no puede ser representada. El dinero es peligroso, se convi...

Alteraciones hepáticas inducidas por la nutrición parenteral

OpenAIRE

J Salas Salvado; A Recaséns Garica

1993-01-01

Liver disorders induced by parenteral nutrition Alteraciones hepáticas inducidas por la nutrición parenteral Liver disorders induced by parenteral nutrition Alteraciones hepáticas inducidas por la nutrición parenteral

Úlceras por presión causadas por dispositivos clínicos

OpenAIRE

Iglesias Ruisánchez, Sandra

2017-01-01

Las úlceras por presión (UPP) son lesiones comunes en los pacientes hospitalizados, especialmente en las unidades de cuidados intensivos (UCI). Los enfermos críticos tienen un riesgo elevado de desarrollar UPP, debido principalmente a la limitación de la movilidad, disminuyendo su capacidad para cambiar activamente su posición en la cama o asiento. Además, el efecto de fármacos anestésicos y sedantes, puede causar una pérdida de la percepción sensorial cutánea. Los diferentes dispositivos clí...

Análise da prevenção e tratamento das úlceras por pressão propostos por enfermeiros Análisis de la prevención y del tratamiento de las úlceras por presión propuesto por enfermeros Analysis of prevention and treatment of the pressure ulcers proposed by nurses

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Adriana Bessa Fernandes Medeiros

2009-03-01

Full Text Available A úlcera por pressão ainda é considerada um problema grave, especialmente em pessoas idosas e nas situações de adoecimento crônico-degenerativo. O objetivo do estudo consistiu em identificar as produções bibliográficas sobre ações de prevenção e tratamento realizadas por enfermeiros publicadas no período de 1999 a 2004, descrevendo o conhecimento produzido na temática. Trata-se de levantamento bibliográfico descritivo de periódicos de enfermagem indexados na LILACS e MEDLINE, acerca da temática no período de 1999 a 2004. A coleta de dados ocorreu entre os meses de maio a junho de 2005. Procedeu-se o exame do material que compreendeu leitura exaustiva, o que proporcionou a identificação de três aspectos estudados: prevenção das úlceras por pressão, tratamento das úlceras por pressão e cuidados de enfermagem às úlceras por pressão. Concluiu-se ainda a necessidade de pesquisas envolvendo a atuação do enfermeiro na avaliação clínica do cliente e no desenvolvimento de programas de prevenção sistematizados.La úlcera por presión, es todavía considerado un problema grave, especialmente en personas ancianas y en las situaciones de enfermedades crónicas degenerativas. El objetivo del estudio consistió en identificar las producciones bibliográficas sobre las acciones de prevención y tratamiento realizadas por enfermeros y publicadas en el período de 1999 a 2004, describiendo el conocimiento producido sobre el tema. Se trata de levantamiento bibliográfico descriptivo de periódicos de enfermería indexados en el LILACS y MEDLINE, acerca de la temática, en el período de 1999 a 2004. La recolección de datos se realizó entre los meses de mayo a junio de 2005. Se procedió a examinar el material con una lectura exhaustiva, lo que proporcionó la identificación de tres aspectos estudiados: prevención de las úlceras por presión, tratamiento de las úlceras por presión y cuidados de enfermería de las

Intoxicação por monofluoroacetato em animais

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Vivian Assunção Nogueira

2011-10-01

Full Text Available O monofluoroacetato (MF ou ácido monofluoroacético é utilizado na Austrália e Nova Zelândia no controle populacional de mamíferos nativos ou exóticos. O uso desse composto é proibido no Brasil, devido ao risco de intoxicação de seres humanos e de animais, uma vez que a substância permanece estável por décadas. No Brasil casos recentes de intoxicação criminosa ou acidental têm sido registrados. MF foi identificado em diversas plantas tóxicas, cuja ingestão determina "morte súbita"; de bovinos na África do Sul, Austrália e no Brasil. O modo de ação dessa substância baseia-se na formação do fluorocitrato, seu metabólito ativo, que bloqueia competitivamente a aconitase e o ciclo de Krebs, o que reduz produção de ATP. As espécies animais têm sido classificadas nas quatro Categorias em função do efeito provocado por MF: (I no coração, (II no sistema nervoso central (III sobre o coração e sistema nervoso central ou (IV com sintomatologia atípica. Neste trabalho, apresenta-se uma revisão crítica atualizada sobre essa substância. O diagnóstico da intoxicação por MF é realizado pelo histórico de ingestão do tóxico, pelos achados clínicos e confirmado por exame toxicológico. Uma forma peculiar de degeneração hidrópico-vacuolar das células epiteliais dos túbulos uriníferos contorcidos distais tem sido considerada como característica dessa intoxicação em algumas espécies. O tratamento da intoxicação por MF é um desafio, pois ainda não se conhece um agente capaz de reverte-la de maneira eficaz; o desfecho geralmente é fatal

positivismo por su reduccionismo epistemológico

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Ignacio M. Ibarzábal

2007-01-01

Full Text Available A lo largo de la historia humana puede observarse la constante oscilación entre diversas teorías científicas. Esto puede demostrarse, por ejemplo, a partir de una reflexión sobre la evolución de las ideas filosóficas desde fines de la edad Media hasta la actualidad. este fenómeno no hace más que poner de relieve cierta inseguridad connatural al hombre, que genera la opción por soluciones simplistas, y “puras”, lo que culmina en muchos casos en una aproximación reduccionista a la realidad. El problema científico que plantea el reduccionismo epistemológico es que éste, al desentenderse de la realidad existencial del hombre, es incapaz de darle respuestas satisfactorias para resolver conflictos. Este inconveniente lo sufre el positivismo jurídico –así como también lo ha padecido el iusnaturalismo ingenuo–, por su imposibilidad de resolver conflictos jurídicos reales; y esto, a causa de su pretendida aproximación avalorativa que da lugar a dos especies de reduccionismos: el que desconoce tajantemente las valoraciones, y aquél que, reconociéndolas, escoge de manera arbitraria los valores objeto de su conocimiento.

Sea urchin granuloma Granulomas por ouriços-do-mar

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André Luiz Rossetto

2006-10-01

Full Text Available Injuries caused by venomous and poisonous aquatic animals may provoke important morbidity in humans. The phylum Echinoderma include more than 6000 species of starfish, sea urchins, sand dollars, and sea cucumbers some of which have been found responsible for injuries to humans. Initial injuries by sea urchins are associated with trauma and envenomation, but later effects can be observed. Sea urchin granuloma is a chronic granulomatous skin disease caused by frequent and successive penetration of sea urchin spines which have not been removed from wounds. The authors report a typical case of sea urchin granuloma in a fisherman and its therapeutic implications.Os acidentes por animais aquáticos traumatizantes e venenosos podem provocar morbidez importante em humanos. Equinodermos marinhos incluem mais de 6000 espécies de estrelas-do-mar, ouriços-do-mar, "bolachas-de-praia" e pepinos-do-mar. Vários equinodermos têm sido responsabilizados por acidentes em humanos. Granulomas por ouriço-do-mar são lesões de caráter granulomatoso, crônicas, causada por acidentes com espículas de ouriço-do-mar. Os autores relatam um caso típico de granulomas por ouriço-do-mar ocorrido em um pescador e enfatizam as implicações terapêuticas aplicadas.

Indultos concedidos por la Cámara de Castilla en tiempos de los Austrias

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José Luis de las HERAS SANTOS

2009-12-01

Full Text Available Maquiavelo aconsejaba a los príncipes que se reservaran para sí la disposición de las materias de gracia. Este principio nunca fue olvidado por los reyes castellanos que consideraron el derecho de perdonar como una regalía. A lo largo del Antiguo Régimen se concedieron perdones reales por motivos diversos: políticos, religiosos, acontecimientos cortesanos, triunfos militares de la monarquía, o merced especial que el soberano deseó hacer a algún subdito. Por el número de afectados pueden clasificarse en generales, si absuelven a un colectivo de reos, o particulares, cuando el agraciado es uno solo. Los generales se regulaban por cédula específica que el rey despachaba al efecto. Su cumplimiento era vigilado por comisiones formadas por miembros de la Cámara, y los aspirantes a sus beneficios no necesitaban presentar solicitud personal ante ningún consejo regio, sino que siendo el caso de los incluidos en la cédula, las justicias de la causa se encargaban de su ejecución. Por está razón este tipo de indultos no han dejado huella en los archivos centrales, salvo las cédulas de concesión. Por el contrario, los individuales eran despachados por la Cámara en nombre del rey después de estudiar los autos procesales y han dejado en los archivos de la corona miles de testimonios. Estos van a ser el objeto de nuestro estudio.

Aumento de consultas en atención primaria por infección respiratoria de vías altas y por fiebre coincidiendo con la gripe (H1N1 2009

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Pablo Aldaz

2011-01-01

Full Text Available Fundamento: En verano de 2009 se registró en Navarra una onda de gripe A (H1N1 2009. Evaluar su repercusión en consultas de atención primaria con diagnóstico diferente al de gripe. Métodos: Estudiamos las consultas en atención primaria del Servicio Navarro de Salud desde el 21 de junio y al 21 de septiembre de 2009 con diagnósticos de gripe (Clasificación Internacional de Atención Primaria, código R80, síndrome febril (código A03, infección respiratoria aguda de vías altas (código R74 y bronquitis aguda (código R78, y las comparamos con las registradas en el mismo periodo en los tres años previos. Resultados: En verano de 2009 se notificaron 3417 casos de síndrome gripal (5,5 por 1.000 habitantes. Entre las semanas 27 y 31 se produjo un brote de gripe, con más de la mitad (87/160 de los frotis de pacientes con síndrome gripal positivos para el virus (H1N1 2009 sin detectarse otros tipos de virus gripal. Coincidiendo con la onda de síndromes gripales observamos aumentos de consultas por síndrome febril e infección respiratoria de vías altas. En comparación con la media de los tres años anteriores, en el verano del 2009 se produjo un incremento del 44! en consultas por síndrome febril (de 3,6 a 5,3 por 1000: p<0,001, del 6! en consultas por infección de vías altas (de 13,2 a 14,1 por 1000; p<0,001 y del 8! en consultas por bronquitis aguda (de 6,3 a 6,9 por 1000; p=0,003. Estos diagnósticos supusieron 3,2 consultas adicionales por 1.000 habitantes atribuibles a la gripe, es decir, un 58! de consultas adicionales. Conclusiones: La gripe se acompaña de aumento en el número de consultas por síndrome febril y por infección respiratoria de vías altas.

Examenes pulmonares por el método de Abreu: sus resultados

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Alfonso Reyes

1950-02-01

definitiva en 1936. Posteriormente el doctor Hanker aplica la Abrengrafía al examen en serio de colectividades. Entre nosotros, fue el doctor Omar Benavides en 1940 quien presentó su trabajo de tesis sobre las primeras abreugrafías tomadas en un aparato ideado por él. En Bogotá, se inició la campaña por este sistema en enero de 1947 con la fundación del Centro Epidemiológico No 1, dirigido por el doctor Antonio Acosta Pinzón.

Micetoma pulmonar por Scedosporium sp, reporte de dos casos

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José G. Somocurcio

2009-07-01

Full Text Available Se reporta los dos primeros casos de micetoma pulmonar por Scedosporium sp, en el Perú, tratados quirúrgicamente en el Hospital Nacional Hipólito Unanue. Se practicó resección pulmonar debido a micetoma pulmonar de donde se tomó muestras que fueron enviadas a microbiología y anatomía patológica para cultivo y estudio histopatológico. Se identificó el moho Scedosporium sp en dos pacientes con secuelas cavitarias por tuberculosis, quienes presentaron tos y hemoptisis de dos meses y tres años de evolución, respectivamente. Radiológicamente las cavidades estaban ocupadas por una "bola fúngica". La histopatología indicó presencia de abundantes hifas, indistinguibles de las de Aspergillus sp, mientras que la inmunodifusión para Aspergillus fue negativa.

GRAVIDADE DE INTOXICAÇÕES POR SANEANTES CLANDESTINOS

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Jessica Adrielle Teixeira Santos

2011-01-01

Full Text Available El presente estudio tuvo como objetivo analizar las intoxicaciones por saneantes comercializados clandestinamente, reportadas en el Centro de Control de Intoxicaciones del Hospital Universitario Regional de Maringá. Es un estudio cuantitativo, con análisis retrospectivo de registros epidemiológicos de personas intoxicadas por estos agentes, en el período de enero de 2005 a diciembre de 2009. De los 118 casos reportados, la mayoría (74-62,7% se produjeron en varones, 105 (88,9% necesitaron de asistencia en unidades de atención de emergencia y hospitalización de alta complejidad, en 14 casos (11,8% requirieron de Cuidados Intensivos, y se reportaron cinco óbitos, todos por intoxicación intencional. Los resultados demuestran la gravedad y la letalidad de este tipo de intoxicación, sugieren la necesidad de medidas urgentes de fiscalización y control de la Vigilancia Sanitaria, así como de medidas para la educación de los consumidores, haciendo hincapié en el papel educativo de la Enfermería

Por uma estrada do M' Boi Mirim sustentável

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Carlos Henrique Santos de Oliveira

2015-10-01

Full Text Available Este artigo trata de avaliar importante via de transporte situada na zona sul da cidade de São Paulo, analisando quais fatores dificultam a circulação de bens e pessoas no espaço urbano, bem como a dificuldade de promover a mobilidade urbana de acordo com os princípios de sustentabilidade, por meio de uma pesquisa qualitativa, exploratória e bibliográfica, com base em um estudo de caso realizado na Estrada do M’ Boi Mirim. Os instrumentos de coleta de dados utilizados foram a observação pessoal, bem como pesquisas em artigos científicos, dissertações e teses relacionadas ao tema. Apesar de essa questão estar sendo amplamente discutida por diversos setores da sociedade, notam-se poucas soluções práticas, haja vista, o crescente uso de transportes individuais motorizados, muitos acidentes nas vias e por muitas vezes, pouca infraestrutura, bem como a falta integração das regiões por meio das vias existentes, principalmente em áreas distantes do centro das cidades.

Algunos aspectos relacionados con las enfermedades tropicales transmitidas por moluscos

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A. Mijail Pérez

1999-12-01

Full Text Available Muchas especies de moluscos son hospedantes de diversos parásitos que provocan infecciones muy serias e incluso mortales en seres humanos y ganado. La esquistosomiasis extendida por 74 países, infecta a unos 200 millones de personas y está en segundo lugar, después de la malaria, como causa de la mortalidad humana originada por parásitos. La infección es causada por un platelminto que se desarrolla en caracoles de agua dulce y que desde el agua puede penetrar en la piel de un ser humano y desarrollarse dentro de sus órganos, produciendo distintos grados de infección, hasta provocar la muerte. Distintas especies de esos caracoles están extendidas por Centro América. El cólera, otra enfermedad que también es mortal, se ha encontrado en moluscos bivalvos comestibles colectados en el Golfo de Nicoya, que bordea Nicaragua y Costa Rica Estas epidemias se pueden combatir con diversos métodos de control de los caracoles hospedantes de parásitos.

Fístula vesicovaginal por litíase: relato de caso

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Chambô Filho Antônio

2003-01-01

Full Text Available As fístulas de etiologia traumática são raras, sobretudo as intrínsecas por litíase vesical. O manejo dessas fístulas tem controvérsias no que diz respeito à técnica cirúrgica ideal. Uma variedade de tratamentos tem sido descrita, incluindo reparação cirúrgica por vias transvaginal e transabdominal. Os autores relatam o caso de uma paciente com queixa de perda urinária contínua com evolução de seis meses, sendo identificado ao exame especular orifício fistuloso no terço médio da parede anterior da vagina, por onde se exteriorizava urina. Nesta topografia, identificava-se, durante o toque bimanual, estrutura de consistência pétrea. A suspeita de litíase vesical foi confirmada pela radiografia de pelve. O tratamento cirúrgico se deu em dois tempos, com exérese do cálculo vesical e posterior correção da fístula por via vaginal.

Agente topológico de aprendizado por reforço

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Arthur Plínio de Souza Braga

2004-01-01

Os métodos de Aprendizagem por Reforço (AR) se mostram adequados para problemas de tomadas de decisões em diversos domínios por sua estrutura flexível e adaptável. Apesar de promissores, os métodos AR frequentemente tem seu campo de atuação prático restrito a problemas com espaço de estados de pequeno ou médio porte devido em muito à forma com que realizam a estimativa da função de avaliação. Nesta tese, uma nova abordagem de AR, denominada de Agente Topológico de Aprendizagem por Reforço (AT...

Detección de anticuerpos antiplasmodium por ELISA en donantes de sangre

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Patricia Olaya de Morales

1982-06-01

Full Text Available La malaria, una enfermedad transmitida por mosquitos del genero anopheles, puede ser inducida a través de transfusiones de sangre infectada con alguna de las especies de Plasmodium que afectan al hombre. Con el objeto de determinar el riesgo potencial de infección inducida por transfusiones, se analizaron durante 9 meses y mediante la técnica de E.L.I.S.A., las muestras de suero tomadas a los donantes de sangre del Hospital Militar Central de Bogotá. El 8.6 por mil de las 3114 muestras analizadas, resultaron positivas para anticuerpos antimaláricos y durante el tiempo del estudio fueron detectados 3 casos de malaria inducida por transfusiones.

Dano cavitacional em revestimentos depositados por aspersão termica a chama

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Paulo Villani Marques

1996-01-01

Resumo: Quantias elevadas são gastas anualmente na manutenção de turbinas hidráulicas usadas na geração de energia elétrica por causa do ataque cavitacional. Avaliou-se a aplicabilidade de revestimentos metálicos e cerâmicos depositados sobre aço carbono por aspersão térmica a chama na manutenção destes equipamentos em função de sua resistência à erosão por cavitação. Foram realizados ensaios de dureza, rugosidade, ensaio acelerado de cavitação induzida por vibração ultra-sônica, adesão (traç...

Nodulose por Metotrexato Methotrexate Induced Nodulosis

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Fernanda Guidolin

2005-08-01

Full Text Available A nodulose por metotrexato (MTX é um dos efeitos colaterais pouco conhecidos do uso desse medicamento em doses baixas. Embora classicamente descrita em casos de artrite reumatóide, tem aparecido, também, em outras doenças reumáticas. Descreve-se aqui um caso de nodulose por MTX em uma paciente com artrite reumatóide soropositiva, que utilizava esse medicamento há um ano, com bom controle do processo articular. Segue-se uma breve revisão sobre o assunto.Methotrexate-induced nodulosis is a rare side effect of this drug when it is used in low doses. Although classically described in rheumatoid arthritis patients, it may also appear in other rheumatic disorders. We describe a seropositive rheumatoid arthritis patient who developed methotrexate-induced nodulosis after using this drug for a year, with good control of articular symptoms. This case presentation is followed by a brief revision on the subject.

Reacciones adversas por antiinflamatorios no esteroideos

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Luisa Ivet Sánchez Ricardo

2011-03-01

Full Text Available Se realizó un estudio descriptivo y transversal en el Consultorio Médico de la Familia No. 28 perteneciente al Policlínico Universitario y Docente "Dr. Mario Muñoz Monroy" desde el 1ro. de junio al 31 de diciembre de 2008, con el objetivo de detectar las reacciones adversas más frecuentes provocadas por el consumo de antiinflamatorios no esteroideos. El universo estuvo constituido por 105 pacientes que asistieron a consulta en el tiempo de estudio y de estos se seleccionó una muestra de 60 pacientes, a quienes se les aplicó un cuestionario de preguntas donde se recogieron las variables de análisis. .Las mujeres resultaron las que más antiinflamatorios consumieron y en el rango de edades de 31-59 años. Las reacciones adversas que más se reportaron fueron la epigastralgia y la hipertensión arterial, así mismo se comprobó la automedicación en algunos pacientes.

Engorde de bagres (Rhamdia quelen) en sistema de cultivo intensivo por sexos separados

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Comolli, J; Roux, J.P; Sánchez, S; Hernández, D

2013-01-01

El bagre sudamericano (ramdiá o jundiá) se caracteriza por rápido crecimiento en los primeros meses de vida e importante diferencia de desarrollo entre ambos sexos. La madurez sexual del macho es precoz, por lo cual la hembra alcanza un peso vivo 30% mayor que el del macho. El presente trabajo tuvo por objetivo analizar el engorde de especimenes de Rhamdia quelen separados por sexos en un sistema intensivo. Se llevaron a cabo tres tratamientos: TA- hembra, TB- mixto y TC- macho. El engorde se...

Coeficiente de fricción por curvatura no intencional en concreto postensado

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Diego Ernesto Dueñas Puentes

2007-09-01

Full Text Available En el presente artículo se establece un coeficiente de fricción por curvatura no intencional (K para puentes de placa y vigas y puentes por voladizos sucesivos a partir de los registros de tensionamiento de algunos puentes postensados construidos en Colombia, el cual es inferior al empleado habitualmente en el diseño de puentes pos-tensados en el país y establecido por el Código Colombiano de Diseño Sísmico de Puentes (CCDSP publicado por el Instituto Nacional de Vías en 1995. Este estudio parte del hecho de que en algunas importantes obras se obtienen alargamientos de torones mayores a los estimados teóricamente, puentes de los cuales se dispone de registros de tensionamiento y de los que se deducen valores de coeficientes más cercanos a los indicados por las últimas ediciones de la Standard Specifications for Highway Bridges, publicada por American Association of State Highway and Transportation Officials “AASHTO”. En Colombia, el CCDSP, considera un coeficiente de fricción por curvatura no intencional (K para cables, con valores entre 0.0050 y 0.00066 m-1, dependiendo del material del que esté fabricado el ducto (acero galvanizado, sin galvanizar, metal brillante, valor superior al encontrado en este trabajo. En este artículo, en primer lugar, se realiza una breve descripción del efecto de fricción a lo largo de los cables, presentando los diferentes valores de coeficientes de fricción indicados en el CCDSP y en “AASHTO.”, en el diseño de puentes preesforzados. Se hace una corta descripción de cada uno de los puentes de los cuales se tienen registros de tensionamiento con el fin de identificar otras variables que intervienen en el proceso de ten-sionamiento como materiales, equipos y mano de obra, y posteriormente, a partir de la validación y tabulación de datos registrados en obra (registros en los cuales se controla la fuerza aplicada y el alargamiento de los torones, se efectuó la evaluación del coeficiente

Bloqueios nervosos guiados por ultra-som Bloqueos nerviosos guiados por ultrasonido Ultrasound-guided nerve blocks

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Pablo Escovedo Helayel

2007-02-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: As técnicas de bloqueios nervosos guiados por ultra-som são baseadas na visualização direta das estruturas nervosas, da agulha de bloqueio e das estruturas anatômicas adjacentes. Desta maneira, é possível depositar a solução de anestésico local precisamente em torno dos nervos e acompanhar a sua dispersão em tempo real, obtendo-se, assim, um bloqueio mais eficaz, de menor latência, menor dependência de referências anatômicas, menor volume de solução anestésica e maior segurança. CONTEÚDO: O artigo revisa os aspectos relativos aos mecanismos físicos para formação de imagens, a anatomia ultra-sonográfica do neuroeixo e dos plexos braquial e lombossacral, os equipamentos e materiais empregados nos bloqueios, os ajustes do aparelho de ultra-som para melhorar as imagens, os planos de visualização das agulhas de bloqueio e as técnicas e o treinamento em bloqueios guiados por ultra-som. CONCLUSÕES: Os passos para se obter sucesso em anestesia regional incluem a identificação exata da posição dos nervos, a localização precisa da agulha, sem lesões nas estruturas adjacentes e, finalmente, a injeção cuidadosa de anestésico local junto aos nervos. Embora a neuroestimulação forneça grande auxílio na identificação dos nervos, esta não consegue, isoladamente, preencher todas essas exigências. Por isso, acredita-se que os bloqueios guiados por ultra-som serão a técnica de eleição para anestesia regional num futuro não muito distante.JUSTIFICATIVA Y OBJETIVOS: Las técnicas de bloqueos nerviosos guiados por ultrasonido se basan en la visualización directa de las estructuras nerviosas, de la aguja de bloqueo y de las estructuras anatómicas adyacentes. De esa manera, se puede depositar la solución de anestésico local precisamente en torno de los nervios y acompañar su dispersión en tiempo real, obteniéndose así, un bloqueo más eficaz, de menor latencia, menor dependencia de

Sinterização ultrarrápida por micro-ondas de compósitos particulados PZT/FCO preparados por mistura em ultrassom

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C. P. Fernandez

Full Text Available Resumo Pós de Pb(Zr0,53Ti0,47O3 (PZT e Fe2CoO4 (FCO, foram sintetizados separadamente pelo método Pechini e misturados em ultrassom, nas proporções molares 80/20 e 50/50 (PZT/FCO. Os compósitos preparados foram prensados e submetidos à sinterização em forno convencional e sinterização ultrarrápida assistida por micro-ondas. A caracterização estrutural e microestrutural das amostras foram realizadas por difração de raios X e microscopia eletrônica de varredura, respectivamente. Medidas de constante dielétrica em função da temperatura, resistividade elétrica e coeficiente de acoplamento magnetoelétrico foram também realizadas. Os resultados evidenciaram que o método de mistura do PZT com a FCO por ultrassom foi rápido e eficiente, gerando, após sinterização, compósitos particulados com conectividade global (0-3 e distribuição uniforme de grãos da fase ferromagnética (FCO na matriz ferroelétrica (PZT. Da análise estrutural, verificou-se que a sinterização por micro-ondas propiciou um arranjo diferenciado no esquema de conectividade local na amostra (1-3 e (2-3, relacionada com a intensificação dos processos de difusão que ocorrem nesse tipo de sinterização principalmente em sistemas nanométricos. Pelos altos valores de resistividade obtidos, comprovou-se que a integridade das fases foi conservada nos dois métodos de sinterização, sendo mais eficiente na sinterização por micro-ondas, característica que garantiu o comportamento magnetoelétrico em todos os compósitos estudados neste trabalho. Os valores do campo Hmax foram dependentes da concentração da fase ferrita e da sinterização; para a composição 80/20 de 1,4 e 1,9 kOe, e para 50/50 de 3,5 e 3,0 kOe nas amostras sinterizadas por micro-ondas e convencionalmente, compatíveis com a literatura e que confirmaram a integridade das fases constituintes PZT e FCO.

Variaciones regionales de la mortalidad por homicidios en Jalisco, México

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Vega-López María Guadalupe

2003-01-01

Full Text Available El presente estudio busca describir las variaciones regionales de la mortalidad por homicidios en el estado de Jalisco, México, en 1989-1991, 1994-1996 y 1999-2000, analizando a su vez el comportamiento de la tasa de homicidios según género y estratos de bienestar socioeconómico. A partir de la información sobre mortalidad generada por el Instituto Nacional de Estadística, Geografía y Informática, se calcularon tasas ajustadas por edad y género e índices de sobremortalidad masculina. Además, se calcularon razones de tasa y su intervalo de confianza (95%. Los resultados reflejan que la tasa de homicidios presenta una tendencia decreciente en los años 90; que existe un patrón regional de la mortalidad por homicidios, observándose las tasas más altas en regiones periféricas del estado consideradas entre las más pobres; que los municipios ubicados en el estrato de bienestar más bajo presentan un exceso de mortalidad por homicidios estadísticamente significativo, y que hay una evidente sobremortalidad masculina por esta causa. Aspectos como los antes descritos implican tareas y desafíos para la salud pública y para los organismos encargados de preservar la ley y el orden, entre ellos la necesidad de implementar políticas intersectoriales diferenciadas, que tomen en consideración las particularidades que rodean al homicidio y al crimen violento en Jalisco.

Analisis cualitativo asistido por computadora Computer-assisted qualitative analysis

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César A. Cisneros Puebla

2003-01-01

Full Text Available Los objetivos de este ensayo son: por un lado, presentar una aproximación a la experiencia hispanoamericana en el Análisis Cualitativo Asistido por Computadora (ACAC al agrupar mediante un ejercicio de sistematización los trabajos realizados por diversos colegas provenientes de disciplinas afines. Aunque hubiese querido ser exhaustivo y minucioso, como cualquier intento de sistematización de experiencias, en este ejercicio son notables las ausencias y las omisiones. Introducir algunas reflexiones teóricas en torno al papel del ACAC en el desarrollo de la investigación cualitativa a partir de esa sistematización y con particular énfasis en la producción del dato es, por otro lado, objetivo central de esta primera aproximación.The aims of this article are: on the one hand, to present an approximation to the Hispano-American experience on Computer-Assisted Qualitative Data Analysis (CAQDAS, grouping as a systematization exercise the works carried out by several colleagues from related disciplines. Although attempting to be exhaustive and thorough - as in any attempt at systematizing experiences - this exercise presents clear lacks and omissions. On the other hand, to introduce some theoretical reflections about the role played by CAQDAS in the development of qualitative investigation after that systematization, with a specific focus on data generation.

Meningitis por Streptococcus suis

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Geffner Sclarsky, D. E.; Moreno Muñoz, R.; Campillo Alpera, Mª.S.; Pardo Serrano, F.J.; Gómez Gómez, A.; Martínez-Lozano, Mª.D.

2001-01-01

La infección humana por Streptococcus suis (S. suis) es una zoonosis, con un riesgo ocupacional conocido y que suele presentarse como meningitis purulenta, que tiene baja mortalidad y frecuentes secuelas de hipoacusia y ataxia. Se han publicado menos de 150 casos humanos desde el informe original de hace 30 años. Hay una reconocida distribución geográfica viviendo la mayoría de los afectados en el norte de Europa y el sudeste Asiático. En España se han comunicado dos pacientes con enfermedad ...

Apendicitis por Paracoccidioides brasiliensis.

OpenAIRE

MUÑOZ URRIBARRI, Ana Beatriz; CHAPARRO DAMMERT, Eduardo; FERRUFINO LLACH, Juan Carlos; VASQUEZ FLORES, Luciola

2012-01-01

La paracoccidioidomicosis es la micosis más prevalente en Sudamérica. La forma aguda afecta el sistema fagocítico mononuclear de niños y personas inmunocomprometidas. El compromiso gastrointestinal es frecuente y su patogenia implica diseminación hematógena y linfática. La linfadenomegalia abdominal causa obstrucción intestinal y abdomen agudo. En este artículo damos a conocer el caso de un niño con compromiso gastrointestinal por apendicitis. Este es el primer caso reportado de apendicitis p...

Evaluación docente y aprendizaje por competencia de los estudiantes

OpenAIRE

Segovia Suller, Cirilo

2016-01-01

Métodos Estadísticos para la Investigación es una asignatura que genera un grado de dificultad en la enseñanza del docente y el aprendizaje del alumno. En el aula se investigó si existe una relación entre la evaluación docente y el aprendizaje por competencias de los estudiantes. El objetivo era determinar la relación entre la evaluación docente y el aprendizaje por competencias de los estudiantes, para luego formular la hipótesis: la evaluación docente se relaciona con el aprendizaje por com...

Fiebre Tifoidea Diagnóstico por pruebas inmunoenzimáticas: Elisa

Directory of Open Access Journals (Sweden)

Miguel Guzmán

1981-06-01

Full Text Available Este trabajo describe el desarrollo y normalización de una técnica inmunoenzimática para el diagnóstico indirecto de la Fiebre Tifoidea. El método permite un análisis simple y objetivo de los resultados. La reacción enzimática es proporcional a la concentración de anticuerpos en el suero contra el antígeno somático-0, por tanto, el método es cuantitativo. Por lo demás, la técnica tiene un alto grado de especificidad para Salmonella typhi, ya que los sueros de pacientes con Salmonelosis causada por Salmonella enteritidis serotipos paratyphi A, B y typhimurium dieron resultados negativos, en forma similar a los presentados por el grupo control antes de la vacunación específica. Los resultados obtenidos con esta técnica permitieron definir el nivel de anticuerpos que puede presentar una población control supuestamente sana frente a los niveles inducidos por la enfermedad. Los resultados postvacunales en el grupo control mostraron títulos sorprendentemente bajos; un análisis de este fenómeno se presentó en forma amplia. Igualmente se proponen futuras investigaciones sobre este campo.